WorldWideScience

Sample records for alternative repository criticality-control

  1. Alternative repository criticality-control strategies for fissile uranium wastes

    International Nuclear Information System (INIS)

    Forsberg, C.W.

    1998-01-01

    Methods to prevent long term, disposal site nuclear criticality from fissile uranium isotopes in wastes were investigated. Long term refers to the time period after waste package (WP) failure and the subsequent loss of geometry and chemistry control within the WP. The preferred method of control was found to be the addition of sufficient depleted uranium to each WP so that the uranium enrichment is reduced to 235 U and 233 U in 238 U

  2. Criticality issues with highly enriched fuels in a repository environment

    International Nuclear Information System (INIS)

    Taylor, L.L.; Sanchez, L.C.; Rath, J.S.

    1998-03-01

    This paper presents preliminary analysis of a volcanic tuff repository containing a combination of low enrichment commercial spent nuclear fuels (SNF) and DOE-owned SNF packages. These SNFs were analyzed with respect to their criticality risks. Disposal of SNF packages containing significant fissile mass within a geologic repository must comply with current regulations relative to criticality safety during transportation and handling within operational facilities. However, once the repository is closed, the double contingency credits for criticality safety are subject to unremediable degradation, (e.g., water intrusion, continued presence of neutron absorbers in proximity to fissile material, and fissile material reconfiguration). The work presented in this paper focused on two attributes of criticality in a volcanic tuff repository for near-field and far-field scenarios: (1) scenario conditions necessary to have a criticality, and (2) consequences of a nuclear excursion that are components of risk. All criticality consequences are dependent upon eventual water intrusion into the repository and subsequent breach of the disposal package. Key criticality parameters necessary for a critical assembly are: (1) adequate thermal fissile mass, (2) adequate concentration of fissile material, (3) separation of neutron poison from fissile materials, and (4) sufficient neutron moderation (expressed in units of moderator to fissile atom ratios). Key results from this study indicated that the total energies released during a single excursion are minimal (comparable to those released in previous solution accidents), and the maximum frequency of occurrence is bounded by the saturation and temperature recycle times, thus resulting in small criticality risks

  3. SUBSURFACE REPOSITORY INTEGRATED CONTROL SYSTEM DESIGN

    International Nuclear Information System (INIS)

    C.J. Fernado

    1998-01-01

    that present preliminary concepts for integrating the diverse set of control systems to be used within the subsurface repository facility (Presented in Section 7.3). (5) Develop initial concepts for an overall subsurface data communication system that can be used to integrate critical and data-intensive control systems (Presented in Section 7.4). (6) Discuss technology trends and control system design issues (Presented in Section 7.5)

  4. SUBSURFACE REPOSITORY INTEGRATED CONTROL SYSTEM DESIGN

    Energy Technology Data Exchange (ETDEWEB)

    C.J. Fernado

    1998-09-17

    present preliminary concepts for integrating the diverse set of control systems to be used within the subsurface repository facility (Presented in Section 7.3). (5) Develop initial concepts for an overall subsurface data communication system that can be used to integrate critical and data-intensive control systems (Presented in Section 7.4). (6) Discuss technology trends and control system design issues (Presented in Section 7.5).

  5. Safety analysis for the Abadia de Goias repository: alternative evaluation of the ingestion dose rate critical distance; Analise de seguranca para o repositorio de Abadia de Goias: avaliacao alternativa da distancia critica de taxa de dose de ingestao

    Energy Technology Data Exchange (ETDEWEB)

    Martin Alves, A.S. de; Passos, E.M. dos [NUCLEN, Rio de Janeiro, RJ (Brazil)

    1995-12-31

    An alternative calculation of the ingestion dose rate critical distance due to a hypothetical release of Cs-137 from the structure of the Repository of Abadia de Goias is presented. The release pathway considers the repository - groundwater region - well - and food chain. The main adopted modification comparing to the previous work is the inclusion of the convective and molecular diffusion terms in the radionuclide transport equation in addition to the radioactive decay term. (author). 6 refs, 1 tab.

  6. SUBSURFACE REPOSITORY INTEGRATED CONTROL SYSTEM DESIGN

    International Nuclear Information System (INIS)

    Randle, D.C.

    2000-01-01

    The primary purpose of this document is to develop a preliminary high-level functional and physical control system architecture for the potential repository at Yucca Mountain. This document outlines an overall control system concept that encompasses and integrates the many diverse process and communication systems being developed for the subsurface repository design. This document presents integrated design concepts for monitoring and controlling the diverse set of subsurface operations. The Subsurface Repository Integrated Control System design will be composed of a series of diverse process systems and communication networks. The subsurface repository design contains many systems related to instrumentation and control (I andC) for both repository development and waste emplacement operations. These systems include waste emplacement, waste retrieval, ventilation, radiological and air monitoring, rail transportation, construction development, utility systems (electrical, lighting, water, compressed air, etc.), fire protection, backfill emplacement, and performance confirmation. Each of these systems involves some level of I andC and will typically be integrated over a data communications network throughout the subsurface facility. The subsurface I andC systems will also interface with multiple surface-based systems such as site operations, rail transportation, security and safeguards, and electrical/piped utilities. In addition to the I andC systems, the subsurface repository design also contains systems related to voice and video communications. The components for each of these systems will be distributed and linked over voice and video communication networks throughout the subsurface facility. The scope and primary objectives of this design analysis are to: (1) Identify preliminary system-level functions and interfaces (Section 6.2). (2) Examine the overall system complexity and determine how and on what levels the engineered process systems will be monitored

  7. Applicability of risk-informed criticality methodology to spent fuel repositories

    International Nuclear Information System (INIS)

    Mays, C.; Thomas, D.A.; Favet, D.

    2000-01-01

    An important objective of geologic disposal is keeping the fissionable material in a condition so that a self-sustaining nuclear chain reaction (criticality) is highly unlikely. This objective supports the overall performance objective of any repository, which is to protect the health and safety of the public by limiting radiological exposure. This paper describes a risk-informed, performance-based methodology, which combines deterministic and probabilistic approaches for evaluating the criticality potential of high-level waste and spent nuclear fuel after the repository is sealed and permanently closed (postclosure). (authors)

  8. Mobility and Criticality of Plutonium in a Repository

    International Nuclear Information System (INIS)

    Kienzler, Bernhard; Loida, Andreas; Maschek, Werner; Rineiski, Andrei

    2003-01-01

    In an underground repository for spent fuel, criticality is excluded initially by compliance with the disposal conditions. In the long term, critical accumulations of fissile material can be formed only by mobilization of uranium and plutonium from the waste forms and subsequent precipitation or sorption of these elements. This paper presents an overview of mechanisms relevant for mobilization and possible accumulation of U and Pu from disposed mixed-oxide fuel elements. Concentrations of fissile materials observed in laboratory corrosion experiments together with model approaches are applied to determine the degree of fissile material accumulation and the risk of a sustained nuclear chain reaction. A prerequisite of criticality in a repository is an accumulation of fissile materials. Since geometry, moderation, and neutron absorption properties cannot be forecast, the neutron multiplication factor k inf is used (instead of k eff ) as a measure of the incidence of criticality. The factor k inf is derived for several scenarios. Required critical masses and critical volumes are evaluated.The accumulation of Pu onto solids is considered, and it is shown how selective enrichment of Pu and U may affect the risk of criticality. It is also shown that the criterion for criticality would be met only in the unrealistic case of selective sorption of 239 Pu. Realistic sorption densities are too low to provide sufficient accumulation of fissile materials for criticality. This is particularly true if high Cl concentrations are present

  9. Postclosure risks of alternative SRP nuclear waste forms in geologic repositories

    International Nuclear Information System (INIS)

    Cheung, H.; Edwards, L.; Harvey, T.; Revelli, M.

    1982-05-01

    The postclosure risk of REFERENCE and ALTERNATIVE waste forms for the defense high-level waste at the Savannah River Plant (SRP) were compared by analyses with a computer code, MISER, written to study the effects of repository features in a probabilistic framework. MISER traces radionuclide flows through a network of stream tubes from the repository to risk-sensitive points. Uncertainties in waste form, package properties, and geotechnical data are accounted for with Monte Carlo techniques. Our results show: (1) for generic layered-salt and basalt repositories, the difference in performance between the two waste forms is insignificant; (2) where the doses are sensitive to uncertainties in leaching rates, the doses are orders of magnitude below background; (3) disruptive events contribute only slightly to the risk of a layered-salt repository; (4) simple design alterations have strong effects on near field doses; (5) great care should be exercised in selecting the location at which repository risks are to be measured, calculated, or regulated

  10. Consideration of criticality in a nuclear waste repository

    International Nuclear Information System (INIS)

    Rechard, R.P.; Sanchez, L.C.; Stockman, C.T.; Ramsey, J.L. Jr.; Martell, M.

    1995-01-01

    The preliminary criticality analysis that was done suggests that the possibility of achieving critical conditions cannot be easily ruled out without looking at the geochemical process of assembly or the dynamics of the operation of a critical assembly. The evaluation of a critical assembly requires an integrated, consistent approach that includes evaluating the following: (1) the alteration rates of the layers of the container and spent fuel, (2) the transport of fissile material or neutron absorbers, and (3) the assembly mechanisms that can achieve critical conditions. The above is a non-trivial analysis and preliminary work suggests that with the loading assumed, enough fissile mass will leach from the HEU multi-purpose canisters to support a criticality. In addition, the consequences of an unpressurized Oklo type criticality would be insignificant to the performance of an unsaturated, tuff repository

  11. Tunnel boring an alternative method in construction of spent fuel repositories

    International Nuclear Information System (INIS)

    Christersson, Jukka

    1984-05-01

    In projecting of the final disposal of nuclear waste in geological formations a great importance should be paid to the selection of the tunneling method. The environment of the chosen repository area should not be exposed to any but as minor disturbances as possible by the excavation method applied. This study approaches full face tunneling methods as an alternative to conventional drill-and-blast methods in the construction of spent fuel repository tunnels. According to experiences up till now it is obvious, that tunnelboring today is fully capable technically competing with conventional tunneling methods, even in the hardest granitic rocks. The most important advantages, it provides for the construction of repositories, are: The methods does not produce any damage in the surrounding rock. Possibility to use placement techniques, which do not require preparing of additive repository holes for the fuel elements. Saving in the use of expensive filling material. The fact, that tunnel boring in hard rock is an expensive alternative, is still valid. Constuction of straight lined tunnels in unfractured rocks by tunnel boring would cost about 30-40% more than by conventional methods. The lay out arrangement of bored tunnels still have a great influence on tunnel boring machine's economy. Due to this it would be round 40-70% more expensive method in the construction of spent fuel repositories. However intensive development w is being carried out to eliminate these limitations and to make machines more flexible. Future trends in tunnel boring look good at the moment. The number of sold units has been increasing and new applications have widen out during last ten years. Harder and more abrasive rocks can now be bored than ever before and the trend seems to continue. It also looks like the cost difference in the hardest rocks is firmly getting smaller and smaller all the time. (author)

  12. The alternative site selection procedure as covered in the report by the Repository Site Selection Procedures Working Group

    International Nuclear Information System (INIS)

    Brenner, M.

    2005-01-01

    The 2002 Act on the Regulated Termination of the Use of Nuclear Power for Industrial Electricity Generation declared Germany's opting out of the peaceful uses of nuclear power. The problem of the permanent management of radioactive residues is becoming more and more important also in the light of that political decision. At the present time, there are no repositories offering the waste management capacities required. Such facilities need to be created. At the present stage, eligible repository sites are the Konrad mine, a former iron ore mine near Salzgitter, and the Gorleben salt dome. While the fate of the Konrad mine as a repository for waste generating negligible amounts of heat continues to be uncertain, despite a plan approval decision of June 2002, the Gorleben repository is still in the planning phase, at present in a dormant state, so to speak. The federal government expressed doubt about the suitability of the Gorleben site. Against this backdrop, the Federal Ministry for the Environment, Nature Conservation, and Nuclear Safety in February 1999 established AkEnd, the Working Group on Repository Site Selection Procedures. The Group was charged with developing, based on sound scientific criteria, a transparent site selection procedure in order to facilitate the search for repository sites. The Working Group presented its final report in December 2002 after approximately four years of work. The Group's proposals about alternative site selection procedures are explained in detail and, above all, reviewed critically. (orig.)

  13. Alternative methods of salt disposal at the seven salt sites for a nuclear waste repository

    International Nuclear Information System (INIS)

    1987-02-01

    This study discusses the various alternative salt management techniques for the disposal of excess mined salt at seven potentially acceptable nuclear waste repository sites: Deaf Smith and Swisher Counties, Texas; Richton and Cypress Creek Domes, Mississippi; Vacherie Dome, Louisiana; and Davis and Lavender Canyons, Utah. Because the repository development involves the underground excavation of corridors and waste emplacement rooms, in either bedded or domed salt formations, excess salt will be mined and must be disposed of offsite. The salt disposal alternatives examined for all the sites include commercial use, ocean disposal, deep well injection, landfill disposal, and underground mine disposal. These alternatives (and other site-specific disposal methods) are reviewed, using estimated amounts of excavated, backfilled, and excess salt. Methods of transporting the excess salt are discussed, along with possible impacts of each disposal method and potential regulatory requirements. A preferred method of disposal is recommended for each potentially acceptable repository site. 14 refs., 5 tabs

  14. Alternative configurations for the waste-handling building at the Yucca Mountain Repository

    International Nuclear Information System (INIS)

    1990-08-01

    Two alternative configurations of the waste-handling building have been developed for the proposed nuclear waste repository in tuff at Yucca Mountain, Nevada. One configuration is based on criteria and assumptions used in Case 2 (no monitored retrievable storage facility, no consolidation), and the other configuration is based on criteria and assumptions used in Case 5 (consolidation at the monitored retrievable storage facility) of the Monitored Retrievable Storage System Study for the Repository. Desirable waste-handling design concepts have been selected and are included in these configurations. For each configuration, general arrangement drawings, plot plans, block flow diagrams, and timeline diagrams are prepared

  15. Calculation of the ingestion critical dose rate for the Goiania radioactive waste repository

    International Nuclear Information System (INIS)

    Passos, E.M. dos; Martin Alves, A.S. De

    1994-01-01

    The calculation results of the critical distance for the ingestion dose rate due to a hypothetical Cs-137 release from the Abadia de Goias repository are shown. The work is based on the pathway repository-aquifer-well food chain. The calculations were based upon analytical models for the migration of radioisotopes through the aquifer and for its transfer from well water to food. (author)

  16. Alternative measure for performance of HLW geologic repository

    International Nuclear Information System (INIS)

    Joonhang, Ahn; Chambre, P.L.

    2001-01-01

    A repository performance model that can show effects of canister multiplicity and repository configuration has been developed. Masses of a radionuclide in the repository and in the far field are proposed as performance measures. Canister multiplicity has significant effects on the release of long-lived radionuclides from the repository. As more canisters are included in the same water stream, the radionuclide concentration in the stream increases, but becomes independent of the number of canisters for sufficiently many canisters. Effects of reduction of radionuclide mass in the repository on the repository performance are clearly observed if the canister multiplicity is taken into account and the mass-based measures are applied. (author)

  17. Repository simulation model: Final report

    International Nuclear Information System (INIS)

    1988-03-01

    This report documents the application of computer simulation for the design analysis of the nuclear waste repository's waste handling and packaging operations. The Salt Repository Simulation Model was used to evaluate design alternatives during the conceptual design phase of the Salt Repository Project. Code development and verification was performed by the Office of Nuclear Waste Isolation (ONWL). The focus of this report is to relate the experience gained during the development and application of the Salt Repository Simulation Model to future repository design phases. Design of the repository's waste handling and packaging systems will require sophisticated analysis tools to evaluate complex operational and logistical design alternatives. Selection of these design alternatives in the Advanced Conceptual Design (ACD) and License Application Design (LAD) phases must be supported by analysis to demonstrate that the repository design will cost effectively meet DOE's mandated emplacement schedule and that uncertainties in the performance of the repository's systems have been objectively evaluated. Computer simulation of repository operations will provide future repository designers with data and insights that no other analytical form of analysis can provide. 6 refs., 10 figs

  18. Preliminary design of the repository. Stage 2

    International Nuclear Information System (INIS)

    Saanio, T.; Kirkkomaeki, T.; Keto, P.; Kukkola, T.; Raiko, H.

    2007-04-01

    Spent nuclear fuel from Finnish nuclear power plants will be disposed of in deep bedrock in Olkiluoto, Eurajoki. The repository is planned to be excavated at a depth of 400 - 500 metres. Access routes to the repository include a 1:10 inclined access tunnel, and vertical shafts. The fuel is encapsulated in the encapsulation plant above ground and transferred to the repository in the canister lift. Deposition tunnels, central tunnels and technical rooms are excavated at the disposal level. The canisters are deposited in deposition holes that are covered with bentonite blocks. The deposition holes are bored in the floors of the deposition tunnels. The central tunnel system consists of two parallel central tunnels that are inter-connected at certain distances. Two parallel central tunnels improve the fire safety of the rooms and also allow flexible backfilling and closing of the deposition tunnels in stages at the operational phase of the repository. An underground rock characterization facility, ONKALO, is excavated at the disposal level to support and confirm investigations carried out from above ground. ONKALO is designed so that it can later serve as part of the repository. ONKALO excavations were started in 2004. The repository will be excavated in the 2010s and operation will start in 2020. The fifth nuclear power unit makes the operational phase of the repository very long. Parts of the repository will be excavated and closed over the long operational period. The repository can be constructed at one or several levels. The one-storey alternative is the so-called reference alternative in this preliminary design report. The two-storey alternative is also taken into account in the ONKALO designs. The preliminary designs of the repository are presented as located in Olkiluoto. The location of the repository will be revised when more information on the bedrock has been gained. More detailed data of the circumstances will be obtained from above ground investigations

  19. Preliminary design of the repository, stage 2

    International Nuclear Information System (INIS)

    Saanio, T.; Kirkkomaeki, T.; Keto, P.; Kukkola, T.; Raiko, H.

    2007-01-01

    Spent nuclear fuel from Finnish nuclear power plants will be disposed of in deep bedrock in Olkiluoto, Eurajoki. The repository is planned to be excavated at a depth of 400 - 500 metres. Access routes to the repository include a 1:10 inclined access tunnel, and vertical shafts. The fuel is encapsulated in the encapsulation plant above ground and transferred to the repository in the canister lift. Deposition tunnels, central tunnels and technical rooms are excavated at the disposal level. The canisters are deposited in deposition holes that are covered with bentonite blocks. The deposition holes are bored in the floors of the deposition tunnels. The central tunnel system consists of two parallel central tunnels that are inter-connected at certain distances. Two parallel central tunnels improve the fire safety of the rooms and also allow flexible backfilling and closing of the deposition tunnels in stages at the operational phase of the repository. An underground rock characterization facility, ONKALO, is excavated at the disposal level to support and confirm investigations carried out from above ground. ONKALO is designed so that it can later serve as part of the repository. ONKALO excavations were started in 2004. The repository will be excavated in the 2010s and operation will start in 2020. The fifth nuclear power unit makes the operational phase of the repository very long. Parts of the repository will be excavated and closed over the long operational period. The repository can be constructed at one or several levels. The one-storey alternative is the so-called reference alternative in this preliminary design report. The two-storey alternative is also taken into account in the ONKALO designs. The preliminary designs of the repository are presented as located in Olkiluoto. The location of the repository will be revised when more information on the bedrock has been gained. More detailed data of the circumstances will be obtained from above ground investigations

  20. Canister transfer into repository in shaft alternative

    International Nuclear Information System (INIS)

    Raiko, H.; Kukkola, T.; Autio, J.

    2005-09-01

    In this report, a study of lift transportation of a massive canister for spent nuclear fuel is considered. The canister is transferred from ground level to repository, which lies in the depth of 400 to 500 m in the bedrock. The canister is a massive metal vessel, whose weight is 19 to 29 tons, and which is strongly irradiant (gamma and neutrons), and which contains 1.4 to 2.2 tons of very strongly radio-active material, the activity of the fuel should not be spread in the environment even during postulated accidents. The study observes that the lift alternative is possible to be built and through good design practices and good maintenance procedures its safety, reliability and usability can be kept on such high level that canister transport is estimated to be licensable. (orig.)

  1. Learning frameworks as an alternative to repositories

    DEFF Research Database (Denmark)

    Dalsgaard, Christian

    2005-01-01

    This paper presents the concept of ‘learning frameworks’. The purpose of the paper is to discuss and question collections of digital learning objects in large repositories and to argue for large learning frameworks which organise a number of thematically related digital learning materials. Whereas...... a learning object repository contains all kinds of materials, a learning framework consists of an organisation of materials related to a common theme. Further, a repository consists of single, self-contained objects, whereas a learning framework is an open-ended environment which presents a number...

  2. Project Alternative Systems Study - PASS. Analysis of performance and long-term safety of repository concepts

    International Nuclear Information System (INIS)

    Birgersson, L.; Skagius, K.; Wiborgh, M.; Widen, H.

    1992-09-01

    This study is part of the Project on Alternative Systems Study, PASS, with the overall aim to perform a technical/economical ranking of alternative repository concepts and canisters for the final storage of spent nuclear fuel. The comparison should in the first stage separately assess technology in construction and operation, long-term performance and safety, and costs. Three of the repository concepts are assumed to be located at a depth of approximately 500 m in the host rock, KBS-3, Very Long Holes (VLH) and Medium Long Holes (MLH). In the KBS-3 concept the canisters are deposited in vertical deposition holes in a system of parallel storage tunnels. In the VLH concept larger canisters are deposited in long horizontal tunnels. The MLH concept, is an evolution of the two other concepts, with KBS-3 type canisters deposited in horizontal tunnels. Smaller canisters are to be deposited in deep bore holes at a depth between 2000 to 4000 m in the Very Deep Holes (VDH) concept. In all concepts the canisters will be surrounded by a bentonite buffer. The aim of the present study is to analyze and compare the performance and long-term safety of the repository concepts. Only a qualitative comparison of the concepts is made as no calculations of radionuclide releases or dose to man have been performed. The ranking of the repository concepts was carried out by comparing the VDH, VLH and MLH concept with the KBS-3 concept. The performance and long-term safety of the repositories located at 500 m level will be based on a multiple barrier system and the predictions for the concepts will involve similar uncertainties. (54 refs.)

  3. Calculation of Upper Subcritical Limits for Nuclear Criticality in a Repository

    International Nuclear Information System (INIS)

    J.W. Pegram

    1998-01-01

    The purpose of this document is to present the methodology to be used for development of the Subcritical Limit (SL) for post closure conditions for the Yucca Mountain repository. The SL is a value based on a set of benchmark criticality multiplier, k eff results that are outputs of the MCNP calculation method. This SL accounts for calculational biases and associated uncertainties resulting from the use of MCNP as the method of assessing k eff . The context for an SL estimate include the range of applicability (based on the set of MCNP results) and the type of SL required for the application at hand. This document will include illustrative calculations for each of three approaches. The data sets used for the example calculations are identified in Section 5.1. These represent three waste categories, and SLs for each of these sets of experiments will be computed in this document. Future MCNP data sets will be analyzed using the methods discussed here. The treatment of the biases evaluated on sets of k eff results via MCNP is statistical in nature. This document does not address additional non-statistical contributions to the bias margin, acknowledging that regulatory requirements may impose additional administrative penalties. Potentially, there are other biases or margins that should be accounted for when assessing criticality (k eff ). Only aspects of the bias as determined using the stated assumptions and benchmark critical data sets will be included in the methods and sample calculations in this document. The set of benchmark experiments used in the validation of the computational system should be representative of the composition, configuration, and nuclear characteristics for the application at hand. In this work, a range of critical experiments will be the basis of establishing the SL for three categories of waste types that will be in the repository. The ultimate purpose of this document is to present methods that will effectively characterize the MCNP

  4. Evaluation of a potential nuclear fuel repository criticality: Lessons learned

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, J.R.; Evans, D.

    1995-10-01

    This paper presents lessons learned from a Probabilistic Risk Assessment (PRA) of the potential for a criticality in a repository containing spent nuclear fuel with high enriched uranium. The insights gained consisted of remarkably detailed conclusions about design issues, failure mechanisms, frequencies and source terms for events up to 10,000 years in the future. Also discussed are the approaches taken by the analysts in presenting this very technical report to a nontechnical and possibly antagonistic audience.

  5. Evaluation of a potential nuclear fuel repository criticality: Lessons learned

    International Nuclear Information System (INIS)

    Wilson, J.R.; Evans, D.

    1995-01-01

    This paper presents lessons learned from a Probabilistic Risk Assessment (PRA) of the potential for a criticality in a repository containing spent nuclear fuel with high enriched uranium. The insights gained consisted of remarkably detailed conclusions about design issues, failure mechanisms, frequencies and source terms for events up to 10,000 years in the future. Also discussed are the approaches taken by the analysts in presenting this very technical report to a nontechnical and possibly antagonistic audience

  6. The procedure of alternative site selection within the report of the study group on the radioactive waste final repository selection process (AKEnd)

    International Nuclear Information System (INIS)

    Brenner, M.

    2005-01-01

    The paper discusses the results of the report of the study group on the radioactive waste final repository selection process with respect to the alternative site selection procedure. Key points of the report are the long-term safety, the alternativity of sites and the concept of one repository. The critique on this report is focussed on the topics site selection and licensing procedures, civil participation, the factor time and the question of cost

  7. Requirements on waste forms for the planned Konrad repository based on criticality calculations

    International Nuclear Information System (INIS)

    Berg, H.P.

    1988-02-01

    In the framework of the safety analyses for the planned Konrad repository it has been investigated whether a criticality incident may be possible during the operational phase or in the post-operational phase. The analysis has shown that the criticality safety is ensured by limitation of a mass concentration of the fissile material in the waste form group and by determination of a maximum permissible mass of fissile material per waste package. The resulting requirements of the waste packages, including a mixture in the cross-section of an emplacement room, are explained. (orig.) [de

  8. The duration of the institutional controls on the low and intermediate level waste repositories

    International Nuclear Information System (INIS)

    Yang Jie; Li Yang; Liu Yafang; Lian Bing; Zhao Yangjun; Chen Hailong; Gu Zhijie

    2014-01-01

    Appropriate institutional controls are put in place prior to repository closure. Such controls can guarantee the long term safety of the repository. Today there is no clear standard on how to determine the institutional control period. This paper tries to give possible factors and activities of the institutional controls on the low and intermediate level waste repositories, and makes some suggestions on the institutional controls in our country. (authors)

  9. The MIMIC Code Repository: enabling reproducibility in critical care research.

    Science.gov (United States)

    Johnson, Alistair Ew; Stone, David J; Celi, Leo A; Pollard, Tom J

    2018-01-01

    Lack of reproducibility in medical studies is a barrier to the generation of a robust knowledge base to support clinical decision-making. In this paper we outline the Medical Information Mart for Intensive Care (MIMIC) Code Repository, a centralized code base for generating reproducible studies on an openly available critical care dataset. Code is provided to load the data into a relational structure, create extractions of the data, and reproduce entire analysis plans including research studies. Concepts extracted include severity of illness scores, comorbid status, administrative definitions of sepsis, physiologic criteria for sepsis, organ failure scores, treatment administration, and more. Executable documents are used for tutorials and reproduce published studies end-to-end, providing a template for future researchers to replicate. The repository's issue tracker enables community discussion about the data and concepts, allowing users to collaboratively improve the resource. The centralized repository provides a platform for users of the data to interact directly with the data generators, facilitating greater understanding of the data. It also provides a location for the community to collaborate on necessary concepts for research progress and share them with a larger audience. Consistent application of the same code for underlying concepts is a key step in ensuring that research studies on the MIMIC database are comparable and reproducible. By providing open source code alongside the freely accessible MIMIC-III database, we enable end-to-end reproducible analysis of electronic health records. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association.

  10. Stochastic and deterministic models to evaluate the critical distance of a near surface repository for the disposal of intermediate and low level radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Alves, A.S.M., E-mail: asergi@eletronuclear.gov.br [Eletrobrás Termonuclear – Eletronuclear S.A. , Rua da Candelária 65, 7° andar, GSN.T, 20091-906 Rio de Janeiro, RJ (Brazil); Melo, P.F. Frutuoso e, E-mail: frutuoso@nuclear.ufrj.br [Graduate Program of Nuclear Engineering, COPPE, Federal University of Rio de Janeiro, Av. Horácio Macedo 2030, Bloco G, sala 206, 21941-914 Rio de Janeiro, RJ (Brazil); Passos, E.M., E-mail: epassos@eletronuclear.gov.br [Eletrobrás Termonuclear – Eletronuclear S.A. , Rua da Candelária 65, 7° andar, GSN.T, 20091-906 Rio de Janeiro, RJ (Brazil); Fontes, G.S., E-mail: gsfontes@hotmail.com [Instituto Militar de Engenharia – IME, Praça General Tibúrcio 80, 22290-270 Rio de Janeiro, RJ (Brazil)

    2015-06-15

    Highlights: • The water infiltration scenario is evaluated for a near surface repository. • The main objective is the determination of the critical distance of the repository. • The column liquid height in the repository is governed by an Ito stochastic equation. • Practical results are obtained for the Abadia de Goiás repository in Brazil. - Abstract: The aim of this paper is to present the stochastic and deterministic models developed for the evaluation of the critical distance of a near surface repository for the disposal of intermediate (ILW) and low level (LLW) radioactive wastes. The critical distance of a repository is defined as the distance between the repository and a well in which the water activity concentration is able to cause a radiological dose to a member of the public equal to the dose limit set by the regulatory body. The mathematical models are developed based on the Richards equation for the liquid flow in the porous media and on the solute transport equation in this medium. The release of radioactive material from the repository to the environment is considered through its base and its flow is determined by Darcy's Law. The deterministic model is obtained from the stochastic approach by neglecting the influence of the Gaussian white noise on the rainfall and the equations are solved analytically with the help of conventional calculus (non-stochastic calculus). The equations of the stochastic model are solved analytically based on the Ito stochastic calculus and numerically by using the Euler–Maruyama method. The impact on the value of the critical distance of the Abadia de Goiás repository is analyzed, taken as a study case, when the deterministic methodology is replaced by the stochastic one, considered more appropriate for modeling rainfall as a stochastic process.

  11. Assessing the demographic and public service impacts of repository siting

    International Nuclear Information System (INIS)

    Murdock, S.H.; Hamm, R.R.

    1983-01-01

    Demographic and public service impacts are likely to be among the most evident of those changes resulting from nuclear waste repository development. Knowledge of the characteristics of such impacts and of the means to assess them is critical. The first section of this chapter examines those likely to be unique to repositories. The second section describes the alternatives for assessing such impacts and the particular difficulties likely to affect the assessments. Given the state of development of techniques for assessing impacts and the range of factors that must be considered, perhaps their best use is as a means of sensitizing decision makers to the potential implications of their decisions. 2 tables

  12. Gabbro as a host rock for a nuclear waste repository

    International Nuclear Information System (INIS)

    Ahlbom, K.; Leijon, B.; Smellie, J.; Liedholm, M.

    1992-09-01

    As an alternative to granitic rocks, gabbro and other basic rock types have been investigated with respect to their suitability to host a nuclear waste repository. The present report summarizes and examines existing geoscientific knowledge of relevance in assessing the potential merits of gabbro as a repository host rock. Implications in terms of site selection, repository construction and post-closure repository performance are also discussed. The objective of the study is to provide a basis for decisions as regards future consideration of the gabbro alternative. It is found that there are rather few gabbro bodies in Sweden, that are potentially of sufficient size to host a repository. Thus, gabbro offers little latitude as regards site selection. In comparison to siting a repository in granitic rocks, this is a major disadvantage, and it may in fact remove gabbro from further consideration. The potential advantages of gabbro refer to repository performance, and include low hydraulic conductivity and a chemical environment promoting efficient radionuclide retardation. However, results from field investigations show that groundwater flow in gabbro bodies is largely controlled by intersecting heterogeneities, in particular granitic dykes, that are significantly more conductive to water than the gabbro. In the far-field scale significant to repository performance, this may reduce or eliminate the potential effects of favourable hydraulic and chemical characteristics of the gabbro itself. In conclusion, there are apparent difficulties associated with siting a repository in gabbro, due to lack of sufficiently large gabbro bodies. On the basis of the present state of knowledge, no decisive differences can be demonstrated when comparing gabbro with granitic rocks, neither with respects to repository construction, nor as regards repository performance. (au)

  13. The alternative site selection procedure as covered in the report by the Repository Site Selection Procedures Working Group; Das Verfahren der alternativen Standortsuche im Bericht des Arbeitskreises Auswahlverfahren Endlagerstandorte

    Energy Technology Data Exchange (ETDEWEB)

    Brenner, M. [Jena Univ. (Germany). Juristische Fakultaet

    2005-01-01

    The 2002 Act on the Regulated Termination of the Use of Nuclear Power for Industrial Electricity Generation declared Germany's opting out of the peaceful uses of nuclear power. The problem of the permanent management of radioactive residues is becoming more and more important also in the light of that political decision. At the present time, there are no repositories offering the waste management capacities required. Such facilities need to be created. At the present stage, eligible repository sites are the Konrad mine, a former iron ore mine near Salzgitter, and the Gorleben salt dome. While the fate of the Konrad mine as a repository for waste generating negligible amounts of heat continues to be uncertain, despite a plan approval decision of June 2002, the Gorleben repository is still in the planning phase, at present in a dormant state, so to speak. The federal government expressed doubt about the suitability of the Gorleben site. Against this backdrop, the Federal Ministry for the Environment, Nature Conservation, and Nuclear Safety in February 1999 established AkEnd, the Working Group on Repository Site Selection Procedures. The Group was charged with developing, based on sound scientific criteria, a transparent site selection procedure in order to facilitate the search for repository sites. The Working Group presented its final report in December 2002 after approximately four years of work. The Group's proposals about alternative site selection procedures are explained in detail and, above all, reviewed critically. (orig.)

  14. Interactive tag cloud visualization of software version control repositories

    CSIR Research Space (South Africa)

    Greene, GJ

    2015-09-01

    Full Text Available Version control repositories contain a wealth of implicit information that can be used to answer many questions about a project’s development process. However, this information is not directly accessible in the version control archives and must...

  15. Learning from nuclear waste repository design: the ground-control plan

    International Nuclear Information System (INIS)

    Schmidt, B.

    1988-01-01

    At present, under a U.S. Department of Energy program, three repositories for commercial spent fuel-in salt, tuff and basalt-are in the phase of site characterization and conceptual design, and one pilot project for defense waste in salt is under development. Because of strict quality assurance requirements throughout design and construction, and the need to predict and ascertain in advance the satisfactory performance of the underground openings, underground openings in the unusual circumstances of the repository environment have been analysed. This will lead to an improved understanding of rock behavior and improved methods of underground analysis and design. A formalized ground control plan was developed, the principles of which may be applied to other types of projects. This paper summarizes the status of underground design and construction for nuclear waste repositories and presents some details of the ground control plan and its individual elements. (author)

  16. Repository design

    Energy Technology Data Exchange (ETDEWEB)

    John, C M

    1982-01-01

    Various technical issues of radioactive waste design are addressed in this paper. Two approaches to repository design considered herein are: (1) design to minimize the disturbance of the hot rock; and (2) designs that intentionally modify the hot rock to insure better containment of the wastes. The latter designs range from construction of a highly impermeable barrier around a spherical cavern to creating a matrix of tunnels and boreholes to form a cage within which the hydraulic pressure is nearly constant. Examples of these design alternatives are described in some detail. It is concluded that proposed designs for repositories illustrate that performance criteria considered acceptable for such facilities can be met by appropriate site selection and repository engineering. With these technically feasible design concepts, it is also felt that socioeconomic and institutional issues can be better resolved. (BLM)

  17. Rock support for nuclear waste repositories

    International Nuclear Information System (INIS)

    Abramson, L.W.; Schmidt, B.

    1984-01-01

    The design of rock support for underground nuclear waste repositories requires consideration of special construction and operation requirements, and of the adverse environmental conditions in which some of the support is placed. While repository layouts resemble mines, design, construction and operation are subject to quality assurance and public scrutiny similar to what is experienced for nuclear power plants. Exploration, design, construction and operation go through phases of review and licensing by government agencies as repositories evolve. This paper discusses (1) the various stages of repository development; (2) the environment that supports must be designed for; (3) the environmental effects on support materials; and (4) alternative types of repository rock support

  18. Centralized mouse repositories.

    Science.gov (United States)

    Donahue, Leah Rae; Hrabe de Angelis, Martin; Hagn, Michael; Franklin, Craig; Lloyd, K C Kent; Magnuson, Terry; McKerlie, Colin; Nakagata, Naomi; Obata, Yuichi; Read, Stuart; Wurst, Wolfgang; Hörlein, Andreas; Davisson, Muriel T

    2012-10-01

    Because the mouse is used so widely for biomedical research and the number of mouse models being generated is increasing rapidly, centralized repositories are essential if the valuable mouse strains and models that have been developed are to be securely preserved and fully exploited. Ensuring the ongoing availability of these mouse strains preserves the investment made in creating and characterizing them and creates a global resource of enormous value. The establishment of centralized mouse repositories around the world for distributing and archiving these resources has provided critical access to and preservation of these strains. This article describes the common and specialized activities provided by major mouse repositories around the world.

  19. Evaluation of alternative spent fuel waste package concepts for a repository in Basalt

    International Nuclear Information System (INIS)

    Hall, G.V.B.; Nair, B.R.

    1986-01-01

    The United States government has established a program for the disposal of spent nuclear fuel and high-level radioactive waste. The Nuclear Waste Policy Act (NWPA) of 1982 requires the first nuclear waste repository to begin receiving high-level radioactive waste in 1998. One of the potentially acceptable sites currently being evaluated is the Hanford Site in the Pasco Basin in the state of Washington where the host rock is basalt. Under the direction of the United States Department of Energy (DOE), Rockwell International's Rockwell Hanford Operations (RHO) has initiated the Basalt Waste Isolation Project (BWIP). The BWIP must design waste packages for emplacement in the repository. As part of the BWIP waste package development program, several alternative designs were considered for the disposal of spent nuclear fuel. This paper describes the concepts that were evaluated, the criteria that was developed for judging their relative merits, and the methodology that was employed. The results of the evaluation show that a Pipe-In-Tunnel design, which uses a long carbon steel pipe for the containment barrier for multiple packages of consolidated spent fuel, has the highest rating. Other designs which had high ratings are also discussed

  20. Enhanced Access Design Alternative I Study

    International Nuclear Information System (INIS)

    Eble, G.B.

    1999-01-01

    The purpose of this document is to evaluate Enhanced Design Alternative (EDA) 1, the low temperature repository design concept (CRWMS M and O 1999a). This technical document will provide supporting information for Site Recommendation (SR) and License Application (LA). Preparation of this evaluation will be in accordance with the technical document preparation plan (TDPP), (CRWMS M and O 1999b). EDA 1, one of five EDAs, was evolved from evaluation of a series of design features and alternatives developed during the first phase of the License Application Design Selection (LADS) process. Low, medium, and high temperature concepts were developed from the design features and alternatives prepared during Phase 1 of the LADS effort (CRWMS M and O 1999a). EDA 1 will first be evaluated against a single Screening Criterion, outlined in CRWMS M and O 1999a, which addresses post-closure performance of the repository. The performance of the repository is defined quantitatively as the peak radiological dose rate to an average individual of a critical group at a distance of 20 km from the repository site within 10,000 years. To satisfy this criterion the peak dose rate must not exceed the anticipated regulatory level of 25 mrem/yr within 10,000 years. If the EDA meets the screening criterion, the EDA will be further evaluated against the LADS Phase 2 Evaluation Criteria contained in CRWMS M and O 1999a

  1. Two factors important to the criticality potential of spent fuel in geologic repositories

    International Nuclear Information System (INIS)

    Gore, B.F.; Jenquin, U.P.

    1981-02-01

    Two factors important to the criticality potential of spent fuel in geologic repositories are: the residual fissile content of the fuel, and the extent to which geochemical processes might somehow separate and accumulate plutonium from other spent fuel materials. This paper presents the results of two calculational surveys defining conditions required for criticality. In the first, homogeneous spherical mixtures of spent fuel actinide oxides and water with water reflection are analyzed. Graphs of minimum critical mass vs duration of in-reactor exposure are presented. Parametric variations from a base case are explored, including the effects of initial enrichment, post exposure radioactive decay and addition of rock materials to the mixture. In the second study, homogeneous spherical mixtures devoid of water, containing plutonium and a neutronically optimized rock material, with a thick rock neutron reflector are analyzed. Graphs of Pu critical mass are presented as a function of concentration over the range from 2 to 100 g Pu/l. Parametric variations from a base case are explored, including effects of rock composition, 240 Pu content and uranium contamination of the plutonium

  2. Critical illness induces alternative activation of M2 macrophages in adipose tissue.

    Science.gov (United States)

    Langouche, Lies; Marques, Mirna B; Ingels, Catherine; Gunst, Jan; Derde, Sarah; Vander Perre, Sarah; D'Hoore, André; Van den Berghe, Greet

    2011-01-01

    We recently reported macrophage accumulation in adipose tissue of critically ill patients. Classically activated macrophage accumulation in adipose tissue is a known feature of obesity, where it is linked with increasing insulin resistance. However, the characteristics of adipose tissue macrophage accumulation in critical illness remain unknown. We studied macrophage markers with immunostaining and gene expression in visceral and subcutaneous adipose tissue from healthy control subjects (n = 20) and non-surviving prolonged critically ill patients (n = 61). For comparison, also subcutaneous in vivo adipose tissue biopsies were studied from 15 prolonged critically ill patients. Subcutaneous and visceral adipose tissue biopsies from non-surviving prolonged critically ill patients displayed a large increase in macrophage staining. This staining corresponded with elevated gene expression of "alternatively activated" M2 macrophage markers arginase-1, IL-10 and CD163 and low levels of the "classically activated" M1 macrophage markers tumor necrosis factor (TNF)-α and inducible nitric-oxide synthase (iNOS). Immunostaining for CD163 confirmed positive M2 macrophage staining in both visceral and subcutaneous adipose tissue biopsies from critically ill patients. Surprisingly, circulating levels and tissue gene expression of the alternative M2 activators IL-4 and IL-13 were low and not different from controls. In contrast, adipose tissue protein levels of peroxisome proliferator-activated receptor-γ (PPARγ), a nuclear receptor required for M2 differentiation and acting downstream of IL-4, was markedly elevated in illness. In subcutaneous abdominal adipose tissue biopsies from surviving critically ill patients, we could confirm positive macrophage staining with CD68 and CD163. We also could confirm elevated arginase-1 gene expression and elevated PPARγ protein levels. Unlike obesity, critical illness evokes adipose tissue accumulation of alternatively activated M2

  3. EEI/UWASTE oversight of the DOE Repository Program by the Repository Information Exchange Team

    International Nuclear Information System (INIS)

    Henkel, C.J.; Supko, E.M.; Schwartz, M.H.

    1993-01-01

    The Utility Nuclear Waste and Transportation Program of the Edison Electric Institute (EEI/UWASTE) has conducted reviews of the US DOE's repository program through its Repository Information Exchange Team (RIET or Team). Eight such reviews have been conducted since 1985 covering topics that include repository program management and control; repository schedule; repository budget; quality assurance; site characterization; repository licensing; environmental issues; and institutional and public information activities. The utility industry has used these repository program reviews as a forum for providing DOE's Office of Civilian Radioactive Waste Management (OCRWM) with comments on the direction of the repository program, advice for future actions regarding quality assurance activities and repository licensing, and suggestions for management and control of the Repository Program. The most significant recommendations made by the utility industry through the RIET are discussed along with any subsequent action by OCRWM in response to or subsequent to utility industry recommendations. The process used by the RIET to develop its recommendations to OCRWM regarding the repository program is also discussed

  4. Enhanced Design Alternative I: Low Temperature Design

    International Nuclear Information System (INIS)

    MacNeil, K.

    1999-01-01

    The purpose of this document is to evaluate Enhanced Design Alternative (EDA) 1, the low temperature repository design concept (CRWMS M and O 1999a). This technical document will provide supporting information for Site Recommendation (SR) and License Application (LA). Preparation of this evaluation will be in accordance with the technical document preparation plan (TDPP), (CRWMS M and O 1999b). EDA 1, one of five EDAs, was evolved from evaluation of a series of design features and alternatives developed during the first phase of the License Application Design Selection (LADS) process. Low, medium, and high temperature concepts were developed from the design features and alternatives prepared during Phase 1 of the LADS effort (CRWMS M and O 1999a). EDA 1 will first be evaluated against a single Screening Criterion, outlined in CRWMS M and O 1999a, which addresses post-closure performance of the repository. The performance of the repository is defined quantitatively as the peak radiological dose rate to an average individual of a critical group at a distance of 20 km from the repository site within 10,000 years. To satisfy this criterion the peak dose rate must not exceed the anticipated regulatory level of 25 mrem/yr within 10,000 years. If the EDA meets the screening criterion, the EDA will be further evaluated against the LADS Phase 2 Evaluation Criteria contained in CRWMS M and O 1999a

  5. Closure of the Spent Fuel Repository in Forsmark - Studies of alternative concepts for sealing of ramp, shafts and investigation boreholes

    Energy Technology Data Exchange (ETDEWEB)

    Gylling, Bjoern [SKB AB, Stockholm (Sweden); Luterkort, David [SGI, Stockholm (Sweden); Johansson, Roland [Miljoe- och Energikonsult AB, Ekeroe (Sweden)

    2012-12-15

    good sealing. Such a solution, which could be based on crushed rock with the right grain size distribution, might also be more robust to control and verify with respect to long-term durability. However, relaxing the design premises in this way would require additional sensitivity analyses. Further, the assessment in SR-Site indicates that the reference design is appropriate for the purpose. However, if the the design premises are relaxed, more robust designs might be worth investigating. This has been studied and the results are presented in this report. Research and development specifically focused on technology for repository closure has not yet been carried out. On the other hand, SKB and other organisations have for many years studied and conducted considerable research on backfilling and sealing of deposition tunnels, including full-scale tests. SKB has also developed and tested technology for sealing of investigation boreholes. Experience and results from these efforts comprise an important basis for this project. The work has focused on sealing of shafts, ramp and investigation boreholes. Alternatives for top sealing and sealing of the central area have not been studied, since their impact on the flow through the repository is judged to be marginal. Nor have alternative concepts for sealing of main and transport tunnels been developed, since it is believed that filling with blocks and pellets of swelling clay is the only alternative that ensures sufficiently low hydraulic conductivity.

  6. Coupling fuel cycles with repositories: how repository institutional choices may impact fuel cycle design

    International Nuclear Information System (INIS)

    Forsberg, C.; Miller, W.F.

    2013-01-01

    The historical repository siting strategy in the United States has been a top-down approach driven by federal government decision making but it has been a failure. This policy has led to dispatching fuel cycle facilities in different states. The U.S. government is now considering an alternative repository siting strategy based on voluntary agreements with state governments. If that occurs, state governments become key decision makers. They have different priorities. Those priorities may change the characteristics of the repository and the fuel cycle. State government priorities, when considering hosting a repository, are safety, financial incentives and jobs. It follows that states will demand that a repository be the center of the back end of the fuel cycle as a condition of hosting it. For example, states will push for collocation of transportation services, safeguards training, and navy/private SNF (Spent Nuclear Fuel) inspection at the repository site. Such activities would more than double local employment relative to what was planned for the Yucca Mountain-type repository. States may demand (1) the right to take future title of the SNF so if recycle became economic the reprocessing plant would be built at the repository site and (2) the right of a certain fraction of the repository capacity for foreign SNF. That would open the future option of leasing of fuel to foreign utilities with disposal of the SNF in the repository but with the state-government condition that the front-end fuel-cycle enrichment and fuel fabrication facilities be located in that state

  7. Critical scientific issues in the demonstration of WIPP compliance with EPA repository standards

    International Nuclear Information System (INIS)

    Weart, W.D.; Chu, M.S.Y.

    1997-01-01

    The Department of Energy submitted a Compliance Certification Application for the Waste Isolation Pilot Plant to the Environmental Protection Agency (EPA) in October, 1996. A critical part of this application was a Performance Assessment which predicts the cumulative radioactive release to the accessible environment over a time period of 10,000 years. Comparison of this predicted release to the EPA standard shows a comfortable margin of compliance. The scientific understanding that was critical to developing this assessment spans a broad range of geotechnical disciplines, and required a thorough understanding of the site's geology and hydrology. Evaluation of the geologic processes which are active in the site region establishes that there will be no natural breach of site integrity for millions of years, far longer than the 10,000 year regulatory period. Inadvertent human intrusion is, therefore, the only credible scenario to lead to potential radioactive release to the accessible environment. To substantiate this conclusion and to quantify these potential releases from human intrusion, it has been necessary to develop an understanding of the following processes: (1) salt creep and shaft seal efficacy; (2) gas generation from organic decomposition of waste materials and anoxic corrosion of metals in the waste and waste packages; (3) solubilities for actinides in brine; (4) fluid flow in Salado formation rocks, and (5) hydrologic transport of actinides in the overlying dolomite aquifers. Other issues which had to be evaluated to allow definition of breach scenarios were brine reservoir occurrences and their associated reservoir parameters, consequences of mining over the repository, and drilling for natural resources in the vicinity of the repository. Results of all these studies will be briefly summarized in this paper

  8. Migration of the Gaudi and LHCb software repositories from CVS to Subversion

    International Nuclear Information System (INIS)

    Clemencic, M; Degaudenzi, H

    2011-01-01

    A common code repository is of primary importance in a distributed development environment such as large HEP experiments. CVS (Concurrent Versions System) has been used in the past years at CERN for the hosting of shared software repositories, among which were the repositories for the Gaudi Framework and the LHCb software projects. Many developers around the world produced alternative systems to share code and revisions among several developers, mainly to overcome the limitations in CVS, and CERN has recently started a new service for code hosting based on the version control system Subversion. The differences between CVS and Subversion and the way the code was organized in Gaudi and LHCb CVS repositories required careful study and planning of the migration. Special care was used to define the organization of the new Subversion repository. To avoid as much as possible disruption in the development cycle, the migration has been gradual with the help of tools developed explicitly to hide the differences between the two systems. The principles guiding the migration steps, the organization of the Subversion repository and the tools developed will be presented, as well as the problems encountered both from the librarian and the user points of view.

  9. Migration of the Gaudi and LHCb software repositories from CVS to Subversion

    Science.gov (United States)

    Clemencic, M.; Degaudenzi, H.; LHCb Collaboration

    2011-12-01

    A common code repository is of primary importance in a distributed development environment such as large HEP experiments. CVS (Concurrent Versions System) has been used in the past years at CERN for the hosting of shared software repositories, among which were the repositories for the Gaudi Framework and the LHCb software projects. Many developers around the world produced alternative systems to share code and revisions among several developers, mainly to overcome the limitations in CVS, and CERN has recently started a new service for code hosting based on the version control system Subversion. The differences between CVS and Subversion and the way the code was organized in Gaudi and LHCb CVS repositories required careful study and planning of the migration. Special care was used to define the organization of the new Subversion repository. To avoid as much as possible disruption in the development cycle, the migration has been gradual with the help of tools developed explicitly to hide the differences between the two systems. The principles guiding the migration steps, the organization of the Subversion repository and the tools developed will be presented, as well as the problems encountered both from the librarian and the user points of view.

  10. Material control and accountability procedures for a waste isolation repository

    International Nuclear Information System (INIS)

    Jenkins, J.D.; Allen, E.J.; Blakeman, E.D.

    1978-05-01

    The material control and accountability needs of a waste isolation repository are examined. Three levels of control are discussed: (1) item identification and control, (2) tamper indication, and (3) quantitative material assay. A summary of waste characteristics is presented and, based on these, plus a consideration of the accessibility of the various types of waste, material control by item identification and accountability (where the individual waste container is the basic unit) is recommended. Tamper indicating procedures are also recommended for the intermediate and low level waste categories

  11. Repository emplacement costs for Al-clad high enriched uranium spent fuel

    International Nuclear Information System (INIS)

    McDonell, W.R.; Parks, P.B.

    1994-01-01

    A range of strategies for treatment and packaging of Al-clad high-enriched uranium (HEU) spent fuels to prevent or delay the onset of criticality in a geologic repository was evaluated in terms of the number of canisters produced and associated repository costs incurred. The results indicated that strategies in which neutron poisons were added to consolidated forms of the U-Al alloy fuel generally produced the lowest number of canisters and associated repository costs. Chemical processing whereby the HEU was removed from the waste form was also a low cost option. The repository costs generally increased for isotopic dilution strategies, because of the substantial depleted uranium added. Chemical dissolution strategies without HEU removal were also penalized because of the inert constituents in the final waste glass form. Avoiding repository criticality by limiting the fissile mass content of each canister incurred the highest repository costs

  12. Towards a Swedish repository for spent fuel

    International Nuclear Information System (INIS)

    Ahlstroem, P.-E.

    1997-01-01

    Nuclear power is producing electricity for the benefit of society but is also leaving radioactive residues behind. It is our responsibility to handle these residues in a safe and proper manner. The development of a system for handling spent fuel from nuclear power plants has proceeded in steps. The same is true for the actual construction of facilities and will continue to be the case for the final repository for spent fuel and other types of long-lived wastes. The primary objective in constructing the repository will be to isolate and contain the radioactive waste. In case the isolation fails for some reason the multibarrier system should retain and retard the radionuclides that might come into contact with the groundwater. A repository is now planned to be built in two steps where the first step will include deposition of about 400 canisters with spent fuel. This first step should be finished in about 20 years from now and be followed by an extensive evaluation of the results from not only this particular step but also from the development of alternative routes before deciding on how to proceed. A special facility to encapsulate the spent fuel is also required. Such an encapsulation plant is proposed to be constructed as an extension of the existing interim storage CLAB. Finding a site for the repository is a critical issue in the implementation of any repository. The siting process started a few years ago and made some progress but is by no means yet completed. It will go on at least into the early part of the next decade. When the present nuclear power plants begin to be due for retirement there should also be some facilities in place to take permanent care of the long-lived radioactive residues. Progress in siting will be a prerequisite for success in our responsibility to make progress towards a safe permanent solution of the waste issue. (orig.)

  13. Foreign materials in the repository - update of estimated quantities

    International Nuclear Information System (INIS)

    Hagros, A.

    2007-03-01

    In a repository for spent nuclear fuel, a variety of materials are used during the construction process and during the operation of the repository. In addition to materials necessary for the construction and operation, some materials may be transported into the repository through the ventilation air, as emissions from vehicles, as waste produced by the staff etc. Both of these two types of materials are considered here and their quantities - both the introduced quantities and the quantities that remain after closure - in the repository constructed at Olkiluoto in Eurajoki, Finland are estimated here based on new information. This work is intended to update the estimations that have been made previously, and it takes advantage of the experience collected during the construction of the underground rock characterisation facility ONKALO at Olkiluoto. During this construction process, the quantities of the different construction materials introduced into the underground openings have been monitored and they form a basis for estimating the quantities to be used in the future. The estimations made in this report are specific to a KBS-3V type repository and to the Olkiluoto site, although in some cases more generic information has been used, particularly when the relevant quantities have not been monitored in the ONKALO. The estimations are based on the new repository layout produced in 2006 and consider the latest plans for grouting and rock support. As these plans are generally not final yet, several different alternative plans are assumed when necessary. Also two different strategies for the backfilling of the tunnels are considered. The most significant differences with respect to the results of an earlier estimation are related to the materials used in grouting, shotcreting and in support bolts. In the cases where a mixture of bentonite and crushed rock is the used backfill alternative, gypsum and cement are the materials with the largest quantities remaining in the

  14. Process mining software repositories

    NARCIS (Netherlands)

    Poncin, W.; Serebrenik, A.; Brand, van den M.G.J.

    2011-01-01

    Software developers' activities are in general recorded in software repositories such as version control systems, bug trackers and mail archives. While abundant information is usually present in such repositories, successful information extraction is often challenged by the necessity to

  15. Control of materials harmful to water in the German Konrad repository - 16125

    International Nuclear Information System (INIS)

    Kugel, Karin; Brennecke, Peter; Steyer, Stephan; Gruendler, Detlef; Boetsch, Wilma; Haider, Claudia

    2009-01-01

    In order to avoid a pollution of the near surface ground water during the post closure phase of the Konrad repository the acceptable amount of material harmful to water in the radioactive waste is restricted. For this purpose the KONRAD plan approval order includes waste requirements referring to the German water law ('water law permission'). In a first part of this contribution the water law permission for the KONRAD repository is introduced. This permission contains a list of materials harmful to water with the respective limitations in mass and many instructions and proposals regarding the registering and balancing of these materials as well as quality assurance aspects. The second part deals with the implementation of the water law permission in the waste acceptance criteria. The waste producer has to describe his waste in a standardized way with respect to the material composition. The operator of the repository has to check this description and to register and balance the materials and substances harmful to water. This procedure is based on a standardized list of materials and a list of containers. In the third part quality control measures used for the proof of the compliance with the acceptance criteria (with respect to the water law permission) are described. In particular objective of the quality control, possible quality control options and acceptable margins are dealt with. (authors)

  16. A new neutron absorber material for criticality control

    International Nuclear Information System (INIS)

    Wells, Alan H.

    2007-01-01

    A new neutron absorber material based on a nickel metal matrix composite has been developed for applications such as the Transport, Aging, and Disposal (TAD) canister for the Yucca Mountain Project. This new material offers superior corrosion resistance to withstand the more demanding geochemical environments found in a 300,000 year to a million year repository. The lifetime of the TAD canister is currently limited to 10,000 years, reflecting the focus of current regulations embodied in 10 CFR 63. The use of DOE-owned nickel stocks from decommissioned enrichment facilities could reduce the cost compared to stainless steel/boron alloy. The metal matrix composite allows the inclusion of more than one neutron absorber compound, so that the exact composition may be adjusted as needed. The new neutron absorber material may also be used for supplementary criticality control of stored or transported PWR spent fuel by forming it into cylindrical pellets that can be inserted into a surrogate control rod. (authors)

  17. Estimated quantities of residual materials in a KBS-3H repository at Olkiluoto

    Energy Technology Data Exchange (ETDEWEB)

    Hagros, Annika (Sannio and Riekkola OY (Finland))

    2008-12-15

    The quantities of residual materials in a KBS-3H type repository have been estimated in this report. The repository is assumed to be constructed at Olkiluoto in Eurajoki, Western Finland. Both the total quantities of the materials introduced into the repository and the quantities of materials that remain in the repository after closure have been calculated. The calculations are largely based on a similar work regarding the material quantities in the Finnish KBS-3V repository and the main goal has been to identify the differences between the KBS-3H and KBS-3V repositories with respect to the type and quantities of residual materials. As the design of the KBS-3H repository is not final yet, the results are only preliminary. Several alternative designs were assumed in the calculations, resulting in different total quantities of materials. The design alternatives that had the greatest effect on the total material quantities were the two different tunnel backfill options, bentonite-crushed rock and Friedland clay. If Friedland clay is used instead of a bentonite-crushed rock mixture, the total quantity of pyrite remaining in the repository is 20 times larger and the quantities of organic materials and gypsum are also increased significantly. The other design alternatives did not have a substantial effect on the total material quantities. The remaining quantity of cement can be reduced by some 20% by selecting the silica grouting alternative in the sealing of the rock mass and low-pH cement in the shotcreting of the repository, instead of using the ordinary cement alternatives. If the total quantity of steel should be minimised, the use of the DAWE design alternative would be better than the Basic Design, although the total reduction would be less than 10%. The main difference between the different drift end plug alternatives is related to the total remaining quantity of silica, which is some 80% smaller if the rock plug is used instead of the LHHP (Low Heat High

  18. Estimated quantities of residual materials in a KBS-3H repository at Olkiluoto

    International Nuclear Information System (INIS)

    Hagros, Annika

    2008-12-01

    The quantities of residual materials in a KBS-3H type repository have been estimated in this report. The repository is assumed to be constructed at Olkiluoto in Eurajoki, Western Finland. Both the total quantities of the materials introduced into the repository and the quantities of materials that remain in the repository after closure have been calculated. The calculations are largely based on a similar work regarding the material quantities in the Finnish KBS-3V repository and the main goal has been to identify the differences between the KBS-3H and KBS-3V repositories with respect to the type and quantities of residual materials. As the design of the KBS-3H repository is not final yet, the results are only preliminary. Several alternative designs were assumed in the calculations, resulting in different total quantities of materials. The design alternatives that had the greatest effect on the total material quantities were the two different tunnel backfill options, bentonite-crushed rock and Friedland clay. If Friedland clay is used instead of a bentonite-crushed rock mixture, the total quantity of pyrite remaining in the repository is 20 times larger and the quantities of organic materials and gypsum are also increased significantly. The other design alternatives did not have a substantial effect on the total material quantities. The remaining quantity of cement can be reduced by some 20% by selecting the silica grouting alternative in the sealing of the rock mass and low-pH cement in the shotcreting of the repository, instead of using the ordinary cement alternatives. If the total quantity of steel should be minimised, the use of the DAWE design alternative would be better than the Basic Design, although the total reduction would be less than 10%. The main difference between the different drift end plug alternatives is related to the total remaining quantity of silica, which is some 80% smaller if the rock plug is used instead of the LHHP (Low Heat High

  19. Management strategy for site characterization at candidate HLW repository sites

    International Nuclear Information System (INIS)

    Bartlett, J.W.

    1988-01-01

    This paper describes a management strategy for HLW repository site characterization which is aimed at producing an optimal characterization trajectory for site suitability and licensing evaluations. The core feature of the strategy is a matrix of alternative performance targets and alternative information-level targets which can be used to allocate and justify program effort. Strategies for work concerning evaluation of expected and disrupted repository performance are distinguished, and the need for issue closure criteria is discussed

  20. The procedure of alternative site selection within the report of the study group on the radioactive waste final repository selection process (AKEnd); Das Verfahren der alternativen Standortsuche im Bericht des Arbeitskreises Auswahlverfahren Endlagerstandorte (AKEnd)

    Energy Technology Data Exchange (ETDEWEB)

    Brenner, M. [Jena Univ. (Germany)

    2005-07-01

    The paper discusses the results of the report of the study group on the radioactive waste final repository selection process with respect to the alternative site selection procedure. Key points of the report are the long-term safety, the alternativity of sites and the concept of one repository. The critique on this report is focussed on the topics site selection and licensing procedures, civil participation, the factor time and the question of cost.

  1. Disposal alternatives and recommendations for waste salt management for repository excavation in the Palo Duro Basin, Texas

    International Nuclear Information System (INIS)

    1987-01-01

    This report documents an evaluation of five alternatives for the disposal of waste salt that would be generated by the construction of a repository for radioactive waste in underground salt deposits at either of two sites in the Palo Duro Basin, Texas. The alternatives include commercial disposal, offsite deep-well injection, disposal in abandoned mines, ocean disposal, and land surface disposal on or off the site. For each alternative a reference case was rated - positive, neutral, or negative - in terms of environmental and dependability factors developed specifically for Texas sites. The factors constituting the environmental checklist relate to water quality impact, water- and land-use conflicts, ecological compatibility, conformity with air quality standards, and aesthetic impact. Factors on the dependability check-list relate to public acceptance, the adequacy of site characterization, permit and licensing requirements, technological requirements, and operational availability. A comparison of the ratings yielded the following viable alternatives, in order of preference: (1) land surface disposal, specifically disposal on tailings piles associated with abandoned potash mines; (2) disposal in abandoned mines, specifically potash mines; and (3) commercial disposal. Approaches to the further study of these three salt management techniques are recommended

  2. Thermal, operational, and economic aspects of repository design alternatives

    International Nuclear Information System (INIS)

    Closs, K.D.; Papp, R.; Bechthold, W.; Engelmann, H.J.; Hartje, B.

    1989-01-01

    This paper discusses how a broad spectrum of heat-generating nuclear waste types like reprocessing waste (HLW, ILW), spent LWR, and spent HTR fuel will be disposed of in a future German repository located in a salt dome. Different package and emplacement concepts for the various waste forms are feasible, ranging from pure borehole emplacement of canisters and drums to pure drift emplacement of heavily shielded casks as well as combinations of both concepts. Optimization of the whole back-end system (waste treatment, interim storage, and disposal) is performed taking into account thermal, operational, and economic aspects. From a radiological viewpoint, the drift emplacement concept is superior to all concepts in as much as the occupational dose is lowest and zero release from the casks is attainable during normal and anomalous repository operation. As far as economics are concerned, the cost of the heavily shielded casks necessary for drift emplacement contributes markedly to the overall cost of the whole back-end system. Drift emplacement can compete economically with the other concepts only if the casks are used both for interim storage and disposal

  3. Criticality control during conditioning of spent nuclear fuel in the Fuel Cycle Facility

    International Nuclear Information System (INIS)

    Lell, R.M.; Khalil, H.S.

    1994-01-01

    Spent nuclear fuel may be unacceptable for direct repository storage because of composition, enrichment, form, physical condition, or the presence of undesirable materials such as sodium. Fuel types which are not acceptable for direct storage must be processed or conditioned to produce physical forms which can safely be stored in a repository. One possible approach to conditioning is the pyroprocess implemented in the Fuel Cycle Facility (FCF) at Argonne National Laboratory-West. Conditioning of binary (U-Zr) and ternary (U-Pu-Zr) metallic fuels from the EBR-2 reactor is used to demonstrate the process. Criticality safety considerations limit batch sizes during the conditioning steps and provide one constraint on the final form of conditioned material. Criticality safety during conditioning is assured by the integration of criticality safety analysis, equipment design, process development, a measurement program, accountability procedures, and a computerized Mass Tracking System. Criticality issues related to storage and shipment of conditioned material have been examined

  4. Factors Affecting Faculty Acceptance and Use of Institutional Repositories in Thailand

    Science.gov (United States)

    Ammarukleart, Sujira

    2017-01-01

    Institutional repositories have been introduced as an innovative and alternative technology for scholarly communication and have received considerable attention from scholars across disciplines and around the globe. While some universities in Thailand have developed and implemented institutional repositories for nearly a decade, knowledge of the…

  5. Repository simulation tests

    International Nuclear Information System (INIS)

    Wicks, G.G.; Bibler, N.E.; Jantzen, C.M.; Plodinec, M.J.

    1984-01-01

    The repository simulation experiments described in this paper are designed to assess the performance of SRP waste glass under the most realistic repository conditions that can be obtained in the laboratory. These tests simulate the repository environment as closely as possible and introduce systematically the variability of the geology, groundwater chemistry, and waste package components during the leaching of the waste glass. The tests evaluate waste form performance under site-specific conditions, which differ for each of the geologic repositories under consideration. Data from these experiments will aid in the development of a realistic source term that can describe the release of radionuclides from SRP waste glass as a component of proposed waste packages. Hence, this information can be useful to optimize waste package design for SRP waste glass and to provide data for predicting long-term performance and subsequent conformance to regulations. The repository simulation tests also help to bridge the gap in interpreting results derived from tests performed under the control of the laboratory to the uncertainity and variability of field tests. In these experiments, site-specific repository components and conditions are emphasized and only the site specific materials contact the waste forms. An important feature of these tests is that both actual and simulated waste glasses are tested identically. 7 figures, 2 tables

  6. Analysis of computational vulnerabilities in digital repositories

    Directory of Open Access Journals (Sweden)

    Valdete Fernandes Belarmino

    2015-04-01

    Full Text Available Objective. Demonstrates the results of research that aimed to analyze the computational vulnerabilities of digital directories in public Universities. Argues the relevance of information in contemporary societies like an invaluable resource, emphasizing scientific information as an essential element to constitute scientific progress. Characterizes the emergence of Digital Repositories and highlights its use in academic environment to preserve, promote, disseminate and encourage the scientific production. Describes the main software for the construction of digital repositories. Method. The investigation identified and analyzed the vulnerabilities that are exposed the digital repositories using Penetration Testing running. Discriminating the levels of risk and the types of vulnerabilities. Results. From a sample of 30 repositories, we could examine 20, identified that: 5% of the repositories have critical vulnerabilities, 85% high, 25% medium and 100% lowers. Conclusions. Which demonstrates the necessity to adapt actions for these environments that promote informational security to minimizing the incidence of external and / or internal systems attacks.Abstract Grey Text – use bold for subheadings when needed.

  7. Economic analysis of waste management alternatives for reprocessing wastes

    International Nuclear Information System (INIS)

    McKee, R.W.; Clark, L.L.; Daling, P.M.; Nesbitt, J.F.; Swanson, J.L.

    1984-02-01

    This study describes the results of a cost analysis of a broad range of alternatives for management of reprocessing wastes that would require geologic repository disposal. The intent was to identify cost-effective alternatives and the costs of potential repository performance requirements. Four integrated treatment facility alternatives for transuranic (TRU) wastes are described and compared. These include no treatment, compaction, incineration, and hulls melting. The advantages of reducing high-level wastes (HLW) volume are also evaluated as are waste transportation alternatives and several performance-related alternatives for emplacing waste in a basalt repository. Results show (1) that system costs for disposal of reprocessing waste are likely to be higher than those for disposal of spent fuel; (2) that volume reduction is cost-effective for both remote-handled (RH) TRU wastes and HLW, and that rail transport for HLW is more cost-effective than truck transport; (3) that coemplacement of RH-TRU wastes with HLW does not have a large cost advantage in a basalt repository; and (4) that, relative to performance requirements, the cost impact for elimination of combustibles is about 5%, long-lived containers for RH-TRU wastes can increase repository costs 10% to 20%, and immediate backfill compared to delayed backfill (bentonite/basalt) around the HLW canisters would increase repository costs up to 10% or overall system costs up to about 5%. 13 references, 4 figures, 12 tables

  8. Suggestions on selection of clay site as a key alternative of underground repository for HLW geological disposal in China

    International Nuclear Information System (INIS)

    Zheng Hualing; Fu Bingjun; Fan Xianhua; Chen Shi; Sun Donghui

    2006-01-01

    Site selection for the underground repository is a vital problem with respect to the HLW geological disposal. Over the past decades, we have been focusing our attention on granite as a priority in China. However, there are some problems have to be discussed on this matter. In this paper, both experiences gained and lessons learned in the international community regarding the site selection are described. And then, after analyzing a lot of some key factors affecting the site selection, some comments and suggestions on selection of clay site as a key alternative before final decision making in China are presented. (authors)

  9. Rethinking regulations for disposal criticality

    International Nuclear Information System (INIS)

    Scott, M.; Doering, T.

    1997-01-01

    This paper provides the basis for the position that the current U.S. Nuclear Regulatory Commission (NRC) criticality regulation is in need of revision to address problems in implementing it for the postclosure period in a geologic high-level waste repository. The authors believe that the applicant for such a facility should be able to demonstrate that postulated postclosure criticality events will not cause unacceptable risk of deleterious effects on public health and safety. In addition, the applicant should be expected to take practical and feasible measures to reduce the probability of a criticality occurring, even if (as expected) the consequences of such a criticality for repository performance and public health and safety would be negligible. This approach, while recognizing the probabilistic nature of analyses of events and conditions in the distant future, is also arguably consistent with the defense in depth concept that has been successfully applied to nuclear reactor regulation. The authors believe regulations for postclosure criticality control should support this dual approach, rather than require a deterministic prohibition of criticality as does the current rule. The existing rule seems appropriate for the preclosure period, as long as it is clearly specified to apply only to that period

  10. Environmental control aspects for fabrication, reprocessing and waste disposal of alternative LWR and LMFBR fuels

    International Nuclear Information System (INIS)

    Nolan, A.M.; Lewallen, M.A.; McNair, G.W.

    1979-11-01

    Environmental control aspects of alternative fuel cycles have been analyzed by evaluating fabrication, reprocessing, and waste disposal operations. Various indices have been used to assess potential environmental control requirements. For the fabrication and reprocessing operations, 50-year dose commitments were used. Waste disposal was evaluated by comparing projected nuclide concentrations in ground water at various time periods with maximum permissible concentrations (MPCs). Three different fabrication plants were analyzed: a fuel fabrication plant (FFP) to produce low-activity uranium and uranium-thorium fuel rods; a plutonium fuel refabrication plant (PFRFP) to produce plutonium-uranium and plutonium-thorium fuel rods; and a uranium fuel refabrication plant (UFRFP) to produce fuel rods containing the high-activity isotopes 232 U and 233 U. Each plant's dose commitments are discussed separately. Source terms for the analysis of effluents from the fuel reprocessing plant (FRP) were calculated using the fuel burnup codes LEOPARD, CINDER and ORIGEN. Effluent quantities are estimated for each fuel type. Bedded salt was chosen for the waste repository analysis. The repository site is modeled on the Waste Isolation Pilot Program site in New Mexico. Wastes assumed to be stored in the repository include high-level vitrified waste from the FRP, packaged fuel residue from the FRP, and transuranic (TRU) contaminated wastes from the FFP, PFRFP, and UFRFP. The potential environmental significance was determined by estimating the ground-water concentrations of the various nuclides over a time span of a million years. The MPC for each nuclide was used along with the estimated ground-water concentration to generate a biohazard index for the comparison among fuel compositions

  11. PREPP criticality control

    International Nuclear Information System (INIS)

    Cargo, C.H.; Becker, G.K.; Berglund, G.R.; O'Connor, N.J.

    1989-03-01

    There is a general lack of data available with regards to criticality control in the use of incineration for full scale processing of TRU waste. In addition to the new analytical tools, such as PRA, are only now starting to be applied to criticality control. These factors have made the development of the PREPP Criticality Control Plan somewhat unique. It is hoped that the PREPP experiences gained in these efforts will provide new insight which will be useful to future facilities processing waste material containing fissile material. 1 fig

  12. New Roles, New Responsibilities: Examining Training Needs of Repository Staff

    Directory of Open Access Journals (Sweden)

    Natasha Simons

    2012-05-01

    Full Text Available INTRODUCTION Institutional repositories play a critical role in the research lifecycle. Funding agencies are increasingly seeking an improved return on their investment in research. Repositories facilitate this process by providing storage of, and access to, institutional research outputs and, more recently, research data. While repositories are generally managed within the academic library, repository staff require different skills and knowledge compared with traditional library roles. This study reports on a survey of Australasian institutional repository staff to identify skills and knowledge sets. METHODS Institutional repository staff working at universities in Australia and New Zealand were invited to participate in an online survey which incorporated both open and closed-ended question types. RESULTS The survey found significant gaps in the current provision of formal training and coursework related to institutional repositories, which echoed findings in the United Kingdom, Italy, and the United States. DISCUSSION There is clearly a need for more and varied training opportunities for repository professionals. Repository work requires a specific set of skills that can be difficult to find and institutions will benefit from investing in training and ongoing development opportunities for repository staff. CONCLUSION The data from this study could be used to facilitate staff recruitment, development, training, and retention strategies.

  13. Requirements for controlling a repository's releases of carbon-14 dioxide; the high costs and negligible benefits

    International Nuclear Information System (INIS)

    Park, U Sun; Pflum, C.G.

    1990-01-01

    A repository excavated within the unsaturated zone may release carbon (C)-14 dioxide in amounts that exceed limits imposed by the Environmental Protection Agency (EPA) and the Nuclear Regulatory Commission (NRC). The release would not threaten the general population, but may expose some hypothetical maximally exposed individual to 0.0005 millirems/year. Yet a repository's releases of C-14 dioxide are strictly regulated, perhaps unintentionally. The EPA and NRC regulations could force the Department of Energy to design and fabricate an expensive 10,000-year waste package solely for the sake of controlling releases of C-14 dioxide. This paper argues that the repository regulations should exempt releases of C-14 dioxide or at least impose more equitable limits. 21 refs., 1 tab

  14. National radioactive waste repository draft EIS. 2 volumes

    International Nuclear Information System (INIS)

    2002-01-01

    Most Australians benefit either directly or indirectly from the medical, industrial and scientific use of radioactive materials. This use produces a small amount of radioactive waste, including low level and short-lived intermediate level radioactive waste such as lightly contaminated soil, plastic, paper, laboratory equipment, smoke detectors, exit signs and gauges.This waste is temporarily stored at more than 100 urban and rural locations around Australia, much of it in buildings that were neither designed nor located for the long-term storage of radioactive material and that are nearing or have reached capacity. Storage locations include hospitals, research institutions, and industry and government stores. Storing such waste in many locations in non-purpose built facilities potentially poses greater risk to the environment and people than disposing of the material in a national, purpose-built repository where the material can be safely managed and monitored. The objectives of the national repository are to: 1. strengthen Australia's radioactive waste management arrangements by promoting the safe and environmentally sound management of low level and short-lived intermediate level radioactive waste 2. provide safe containment of these wastes until the radioactivity has decayed to background levels. To meet these objectives, it is proposed to construct a national near-surface repository at either the preferred site on the Woomera Prohibited Area (WPA) or either of the two nearby alternative sites. The facility is not intended for the disposal of radioactive ores from mining. A national store for long-lived intermediate level waste will not be co-located with the national repository, and would be subject to a separate environmental assessment process.One preferred and two alternative sites have been selected for the national repository, following an extensive site selection process. All three sites are located in northern South Australia in a region known as central

  15. Repository and deep borehole disposition of plutonium

    International Nuclear Information System (INIS)

    Halsey, W.G.

    1996-02-01

    Control and disposition of excess weapons plutonium is a growing issue as both the US and Russia retire a large number of nuclear weapons> A variety of options are under consideration to ultimately dispose of this material. Permanent disposition includes tow broad categories: direct Pu disposal where the material is considered waste and disposed of, and Pu utilization, where the potential energy content of the material is exploited via fissioning. The primary alternative to a high-level radioactive waste repository for the ultimate disposal of plutonium is development of a custom geologic facility. A variety of geologic facility types have been considered, but the concept currently being assessed is the deep borehole

  16. The deep disposal repository - an alternative general arrangement

    International Nuclear Information System (INIS)

    Wolofsky, L.

    1996-01-01

    For the disposal of nuclear fuel waste in Canada the current proposal requires a repository at or below 500 m depth in Precambrian plutonic igneous rock in Ontario, consisting of numerous horizontal parallel tunnels arranged in one or more horizontal planes i.e. a room-and-pillar arrangement. The pillars are three times as wide as the tunnels, giving as extraction ratio of 25%. The tunnels are tentatively designed to be excavated by drill and blast, with a flat-arched roof, vertical side walls and a flat invert. The fuel containing canisters are to be surrounded by a low-permeability bentonite-based buffer in vertical holes drilled for the purpose in the invert

  17. Limiting critical speed response on the SSME Alternate High Pressure Fuel Turbopump (ATD HPFTP) with bearing deadband

    Science.gov (United States)

    Goggin, David G.; Darden, J. M.

    1992-01-01

    Yammamoto (1954) described the influence of bearing deadband on the critical speed response of a rotor-bearing system. Practical application of these concepts to limit critical speed response of turbopump rotors is described. Nonlinear rotordynamic analyses are used to define the effect of bearing deadband and rotor unbalance on the Space Shuttle Main Engine Alternate High Pressure Fuel Turbopump. Analysis results are used with hot fire test data to verify the presence of a lightly damped critical speed within the operating speed range. With the proper control of rotor unbalance and bearing deadband, the response of this critical speed is reduced to acceptable levels without major design modifications or additional sources of damping.

  18. Shared Medical Imaging Repositories.

    Science.gov (United States)

    Lebre, Rui; Bastião, Luís; Costa, Carlos

    2018-01-01

    This article describes the implementation of a solution for the integration of ownership concept and access control over medical imaging resources, making possible the centralization of multiple instances of repositories. The proposed architecture allows the association of permissions to repository resources and delegation of rights to third entities. It includes a programmatic interface for management of proposed services, made available through web services, with the ability to create, read, update and remove all components resulting from the architecture. The resulting work is a role-based access control mechanism that was integrated with Dicoogle Open-Source Project. The solution has several application scenarios like, for instance, collaborative platforms for research and tele-radiology services deployed at Cloud.

  19. Federated repositories of X-ray diffraction images.

    Science.gov (United States)

    Androulakis, Steve; Schmidberger, Jason; Bate, Mark A; DeGori, Ross; Beitz, Anthony; Keong, Cyrus; Cameron, Bob; McGowan, Sheena; Porter, Corrine J; Harrison, Andrew; Hunter, Jane; Martin, Jennifer L; Kobe, Bostjan; Dobson, Renwick C J; Parker, Michael W; Whisstock, James C; Gray, Joan; Treloar, Andrew; Groenewegen, David; Dickson, Neil; Buckle, Ashley M

    2008-07-01

    There is a pressing need for the archiving and curation of raw X-ray diffraction data. This information is critical for validation, methods development and improvement of archived structures. However, the relatively large size of these data sets has presented challenges for storage in a single worldwide repository such as the Protein Data Bank archive. This problem can be avoided by using a federated approach, where each institution utilizes its institutional repository for storage, with a discovery service overlaid. Institutional repositories are relatively stable and adequately funded, ensuring persistence. Here, a simple repository solution is described, utilizing Fedora open-source database software and data-annotation and deposition tools that can be deployed at any site cheaply and easily. Data sets and associated metadata from federated repositories are given a unique and persistent handle, providing a simple mechanism for search and retrieval via web interfaces. In addition to ensuring that valuable data is not lost, the provision of raw data has several uses for the crystallographic community. Most importantly, structure determination can only be truly repeated or verified when the raw data are available. Moreover, the availability of raw data is extremely useful for the development of improved methods of image analysis and data processing.

  20. Categorical Alternatives: An Educational Criticism Study

    Directory of Open Access Journals (Sweden)

    Elizabeth J. EVANS

    2015-12-01

    Full Text Available In the writing of this paper, the design of which is based on Elliot Eisners Educational Criticism model, both linguistic and non-linguistic description were used to encourage the interpretation and evaluation of a specific and unique alternative educational setting. Five years ago, Ellens Learning Annex, a multi-age, one-room school house, was just next door to the researcher, while her son was struggling at the public school a mile away. A day spent observing Ellen and her students yielded data from which three general themes emerged: Heterogeneous age-grouping, place-based education, and sensory integration in a teaching and learning environment.

  1. Control of criticality; Kawalan kegentingan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-12-31

    The chapter briefly discussed the following subjects: basic and the principle of criticality, natural uranium, neutron utilization, criticality data for systems, criticality accidents, criticality control i.e. mass, volume and geometry control .

  2. Seal design alternatives study

    International Nuclear Information System (INIS)

    Van Sambeek, L.L.; Luo, D.D.; Lin, M.S.; Ostrowski, W.; Oyenuga, D.

    1993-06-01

    This report presents the results from a study of various sealing alternatives for the WIPP sealing system. Overall, the sealing system has the purpose of reducing to the extent possible the potential for fluids (either gas or liquid) from entering or leaving the repository. The sealing system is divided into three subsystems: drift and panel seals within the repository horizon, shaft seals in each of the four shafts, and borehole seals. Alternatives to the baseline configuration for the WIPP seal system design included evaluating different geometries and schedules for seal component installations and the use of different materials for seal components. Order-of-magnitude costs for the various alternatives were prepared as part of the study. Firm recommendations are not presented, but the advantages and disadvantages of the alternatives are discussed. Technical information deficiencies are identified and studies are outlined which can provide required information

  3. Assessment of alternative disposal concepts

    Energy Technology Data Exchange (ETDEWEB)

    Autio, J.; Saanio, T.; Tolppanen, P. [Saanio and Riekkola Consulting Engineers, Helsinki (Finland); Raiko, H.; Vieno, T. [VTT Energy, Espoo (Finland); Salo, J.P. [Posiva Oy, Helsinki (Finland)

    1996-12-01

    Four alternative repository designs for the disposal of spent nuclear in the Finnish crystalline bedrock were assessed in the study. The alternatives were: (1) the basic KBS-3 design in which copper canisters are emplaced in vertical deposition holes bored in the floors of horizontal tunnels, (2) the KBS-3-2C design with two canisters in a deposition hole, (3) Short Horizontal Holes (SHH) in the side walls of the tunnels, and (4) the Medium Long Holes (MLH) concept in which approximately 25 canisters are emplaced in a horizontal deposition hole about 200 metres in length bored between central and side tunnels. In all the alternatives considered, the thickness of the layer of compacted bentonite between copper canister and bedrock is 35 cm. Two different copper canister designs were also assessed. Technical feasibility and flexibility, post-closure safety and repository cost were assessed for each of the alternative canister and repository designs. On the basis of this assessment it is recommended that further development and studies should focus on the vacuum- or inert gas-filled cast insert type copper canister and the basic KBS-3 type repository design with a single canister in a vertical deposition hole. The KBS-3 design is robust and flexible and provides excellent post-closure safety. The transfer, emplacement and sealing operations are technically uncomplicated. The alternative options assessed do not offer any significant benefits in safety or cost over the basic design, but they are technically more complex and also in some respects more vulnerable to malfunction during the emplacement of canisters and buffer, as well as common mode failures. (60 refs.).

  4. Assessment of alternative disposal concepts

    International Nuclear Information System (INIS)

    Autio, J.; Saanio, T.; Tolppanen, P.; Raiko, H.; Vieno, T.; Salo, J.P.

    1996-12-01

    Four alternative repository designs for the disposal of spent nuclear in the Finnish crystalline bedrock were assessed in the study. The alternatives were: (1) the basic KBS-3 design in which copper canisters are emplaced in vertical deposition holes bored in the floors of horizontal tunnels, (2) the KBS-3-2C design with two canisters in a deposition hole, (3) Short Horizontal Holes (SHH) in the side walls of the tunnels, and (4) the Medium Long Holes (MLH) concept in which approximately 25 canisters are emplaced in a horizontal deposition hole about 200 metres in length bored between central and side tunnels. In all the alternatives considered, the thickness of the layer of compacted bentonite between copper canister and bedrock is 35 cm. Two different copper canister designs were also assessed. Technical feasibility and flexibility, post-closure safety and repository cost were assessed for each of the alternative canister and repository designs. On the basis of this assessment it is recommended that further development and studies should focus on the vacuum- or inert gas-filled cast insert type copper canister and the basic KBS-3 type repository design with a single canister in a vertical deposition hole. The KBS-3 design is robust and flexible and provides excellent post-closure safety. The transfer, emplacement and sealing operations are technically uncomplicated. The alternative options assessed do not offer any significant benefits in safety or cost over the basic design, but they are technically more complex and also in some respects more vulnerable to malfunction during the emplacement of canisters and buffer, as well as common mode failures. (60 refs.)

  5. Knowledge repositories for multiple uses

    Science.gov (United States)

    Williamson, Keith; Riddle, Patricia

    1991-01-01

    In the life cycle of a complex physical device or part, for example, the docking bay door of the Space Station, there are many uses for knowledge about the device or part. The same piece of knowledge might serve several uses. Given the quantity and complexity of the knowledge that must be stored, it is critical to maintain the knowledge in one repository, in one form. At the same time, because of quantity and complexity of knowledge that must be used in life cycle applications such as cost estimation, re-design, and diagnosis, it is critical to automate such knowledge uses. For each specific use, a knowledge base must be available and must be in a from that promotes the efficient performance of that knowledge base. However, without a single source knowledge repository, the cost of maintaining consistent knowledge between multiple knowledge bases increases dramatically; as facts and descriptions change, they must be updated in each individual knowledge base. A use-neutral representation of a hydraulic system for the F-111 aircraft was developed. The ability to derive portions of four different knowledge bases is demonstrated from this use-neutral representation: one knowledge base is for re-design of the device using a model-based reasoning problem solver; two knowledge bases, at different levels of abstraction, are for diagnosis using a model-based reasoning solver; and one knowledge base is for diagnosis using an associational reasoning problem solver. It was shown how updates issued against the single source use-neutral knowledge repository can be propagated to the underlying knowledge bases.

  6. Refinancing of the search for a repository and of the repository for heat generating radioactive Waste. Pt. 2

    International Nuclear Information System (INIS)

    Moench, Christoph

    2013-01-01

    Part I of this article, which appeared in the preceding issue, described in general terms the background to the search for a disposal site and the result of the exploration to date of the repository, which would appear to be suitable from a mining standpoint according to the present knowledge. According to the rules in effect up to now, the exploration and construction would be financed by advance payments on the contributions of the waste producing companies, in particular the utility companies. The working draft of an 'Act on the search for and selection of a site for a repository for heat generating radioactive waste' (Gesetz zur Suche und Auswahl eines Standortes fuer ein Endlager fuer waermeentwickelnde radioaktive Abfaelle) from autumn 2012 provides for a new version of section 21b Atomic Energy Act, under which the costs for 'carrying out a repository selection procedure pursuant to the Repository Selection Act (Standort-auswahlgesetz)' would be allocated to the future users of the repository who are obliged to make contributions as a 'necessary expense'. Part II evaluates this provision of the working draft on the basis of the financial constitutional law. A comparison of sites is not a measure that could be allocated to the future users of the repository who are obliged to make contributions as a 'necessary expense'. Moreover, there is a lack of responsibility for the financing and of a legally relevant advantage that would be conferred by a cumulative alternative repository search for the later users of the repository who are obliged to provide the pre-financing. The costs can therefore not be allocated to the later users as either a contribution or a special charge, not even by way of an association with mandatory membership (Zwangsverband). They must be borne by the state. Consequently, the allocation stipulated by provision would constitute an impermissible charge under financial constitutional law. (orig.)

  7. Technical basis for high-level waste repository land control requirements for Palo Duro Basin, Paradox Basin, and Richton Dome

    International Nuclear Information System (INIS)

    Chen, C.P.; Raines, G.E.

    1987-02-01

    Three sites, the Palo Duro Basin in Texas, the Paradox Basin in Utah, and the Richton Dome in Mississippi, are being investigated by the US Department of Energy for high-level radioactive-waste disposal in mined, deep geologic repositories in salt. This report delineates the use of regulatory, engineering, and performance assessment information to establish the technical basis for controlled area requirements. Based on the size of the controlled area determined, plus that of the geologic repository operations area, recommendations of possible land control or ownership area requirements for each locale are provided. On a technical basis, the following minimum land control or ownership requirements are recommended, assuming repository operations area of 2240 ac (907 ha), or 3.5 mi 2 (9.1 km 2 ): Palo Duro Basin - 4060 ac (1643 ha), or 6.3 mi 2 (16.4 km 2 ); Paradox Basin - 4060 ac (1643 ha), or 6.3 mi 2 (16.4 km 2 ); and Richton Dome - 5000 ac (2024 ha), or 7.8 mi 2 (20.2 km 2 ). Of the factors used to determine the technically based recommendations, one was found to dominate each locale. For the Palo Duro and Paradox Basins, the dominant factor was the need to limit potential radionuclide release by ground-water flow to the accessible environment. For the Richton Dome, the dominant factor was the need to limit the potential effects of solution mining on dome and repository integrity

  8. Critical assessment of seismic and geomechanics literature related to a high-level nuclear waste underground repository

    Energy Technology Data Exchange (ETDEWEB)

    Kana, D.D.; Vanzant, B.W.; Nair, P.K. [Southwest Research Inst., San Antonio, TX (USA). Center for Nuclear Waste Regulatory Analyses; Brady, B.H.G. [ITASCA Consulting Group, Inc., Minneapolis, MN (USA)

    1991-06-01

    A comprehensive literature assessment has been conducted to determine the nature and scope of technical information available to characterize the seismic performance of an underground repository and associated facilities. Significant deficiencies were identified in current practices for prediction of seismic response of underground excavations in jointed rock. Conventional analytical methods are based on a continuum representation of the host rock mass. Field observations and laboratory experiments indicate that, in jointed rock, the behavior of the joints controls the overall performance of underground excavations. Further, under repetitive seismic loading, shear displacement develops progressively at block boundaries. Field observations correlating seismicity and groundwater conditions have provided significant information on hydrological response to seismic events. However, lack of a comprehensive model of geohydrological response to seismicity has limited the transportability conclusions from field observations. Based on the literature study, matters requiring further research in relation to the Yucca Mountain repository are identified. The report focuses on understanding seismic processes in fractured tuff, and provides a basis for work on the geohydrologic response of a seismically disturbed rock mass. 220 refs., 43 figs., 11 tabs.

  9. Critical assessment of seismic and geomechanics literature related to a high-level nuclear waste underground repository

    International Nuclear Information System (INIS)

    Kana, D.D.; Vanzant, B.W.; Nair, P.K.

    1991-06-01

    A comprehensive literature assessment has been conducted to determine the nature and scope of technical information available to characterize the seismic performance of an underground repository and associated facilities. Significant deficiencies were identified in current practices for prediction of seismic response of underground excavations in jointed rock. Conventional analytical methods are based on a continuum representation of the host rock mass. Field observations and laboratory experiments indicate that, in jointed rock, the behavior of the joints controls the overall performance of underground excavations. Further, under repetitive seismic loading, shear displacement develops progressively at block boundaries. Field observations correlating seismicity and groundwater conditions have provided significant information on hydrological response to seismic events. However, lack of a comprehensive model of geohydrological response to seismicity has limited the transportability conclusions from field observations. Based on the literature study, matters requiring further research in relation to the Yucca Mountain repository are identified. The report focuses on understanding seismic processes in fractured tuff, and provides a basis for work on the geohydrologic response of a seismically disturbed rock mass. 220 refs., 43 figs., 11 tabs

  10. Developing criteria to establish Trusted Digital Repositories

    Science.gov (United States)

    Faundeen, John L.

    2017-01-01

    This paper details the drivers, methods, and outcomes of the U.S. Geological Survey’s quest to establish criteria by which to judge its own digital preservation resources as Trusted Digital Repositories. Drivers included recent U.S. legislation focused on data and asset management conducted by federal agencies spending $100M USD or more annually on research activities. The methods entailed seeking existing evaluation criteria from national and international organizations such as International Standards Organization (ISO), U.S. Library of Congress, and Data Seal of Approval upon which to model USGS repository evaluations. Certification, complexity, cost, and usability of existing evaluation models were key considerations. The selected evaluation method was derived to allow the repository evaluation process to be transparent, understandable, and defensible; factors that are critical for judging competing, internal units. Implementing the chosen evaluation criteria involved establishing a cross-agency, multi-disciplinary team that interfaced across the organization. 

  11. Preliminary concepts: materials management in an internationally safeguarded nuclear-waste geologic repository

    International Nuclear Information System (INIS)

    Ostenak, C.A.; Whitty, W.J.; Dietz, R.J.

    1979-11-01

    Preliminary concepts of materials accountability are presented for an internationally safeguarded nuclear-waste geologic repository. A hypothetical reference repository that receives nuclear waste for emplacement in a geologic medium serves to illustrate specific safeguards concepts. Nuclear wastes received at the reference repository derive from prior fuel-cycle operations. Alternative safeguards techniques ranging from item accounting to nondestructive assay and waste characteristics that affect the necessary level of safeguards are examined. Downgrading of safeguards prior to shipment to the repository is recommended whenever possible. The point in the waste cycle where international safeguards may be terminate depends on the fissile content, feasibility of separation, and practicable recoverability of the waste: termination may not be possible if spent fuels are declared as waste

  12. Design Alternative Evaluation No. 3: Post-Closure Ventilation

    International Nuclear Information System (INIS)

    Logan, R.C.

    1999-01-01

    The objective of this study is to provide input to the Enhanced Design Alternatives (EDA) for License Application Design Selection (LADS). Its purpose is to develop and evaluate conceptual designs for post-closure ventilation alternatives that enhance repository performance. Post-closure ventilation is expected to enhance repository performance by limiting the amount of water contacting the waste packages. Limiting the amount of water contacting the waste packages will reduce corrosion

  13. Repository site characterization

    International Nuclear Information System (INIS)

    Voss, J.W.; Pentz, D.L.

    1987-01-01

    The characterization of candidate repository sites has a number of programmatic objectives. Principal among these is the acquisition of data: a) to determine the suitability of a site relative to the DOE repository siting guidelines, b) to support model development and calculations to determine the suitability of a site relative to the post closure criteria of the NRC and EPA, c) to support the design of a disposal system, including the waste package and the engineered barrier system, as well as the shafts and underground openings of the repository. In meeting the gaols of site characterization, the authors have an obligation to conduct their investigations within an appropriate budget and schedule. This mandates that a well-constructed and systematic plan for field investigations be developed. Such a plan must fully account for the mechanisms which will control the radiologic performance in the repository. The plan must also flexibly and dynamically respond to the results of each step of field investigation, responding to the spatial variability of earth as well as to enhanced understandings of the performance of the disposal system. Such a plan must ensure that sufficient data are available to support the necessary probabilistic calculations of performance. This paper explores the planning for field data acquisition with specific reference to requirements for demonstrations of the acceptable performance for disposal systems

  14. Scenario Analysis for the Safety Assessment of Nuclear Waste Repositories: A Critical Review.

    Science.gov (United States)

    Tosoni, Edoardo; Salo, Ahti; Zio, Enrico

    2018-04-01

    A major challenge in scenario analysis for the safety assessment of nuclear waste repositories pertains to the comprehensiveness of the set of scenarios selected for assessing the safety of the repository. Motivated by this challenge, we discuss the aspects of scenario analysis relevant to comprehensiveness. Specifically, we note that (1) it is necessary to make it clear why scenarios usually focus on a restricted set of features, events, and processes; (2) there is not yet consensus on the interpretation of comprehensiveness for guiding the generation of scenarios; and (3) there is a need for sound approaches to the treatment of epistemic uncertainties. © 2017 Society for Risk Analysis.

  15. Study of nuclear waste storage capacity at Yucca mountain repository

    International Nuclear Information System (INIS)

    Zhou Wei; Apted, M.; Kessler, J.H.

    2008-01-01

    The Yucca Mountain repository is applying license for storing 70000 MTHM nuclear waste including commercial spent nuclear fuel (CSNF) and defense high-level radioactive waste (HLW). The 70000 MTHM is a legal not the technical limit. To study the technical limit, the Electric Power Research Institute (EPRI) carried out a systematic study to explore the potential impact if the repository will accept more waste. This paper describes the model and results for evaluating the spent-fuel disposal capacity for a repository at Yucca Mountain from the thermal and hydrological point of view. Two proposed alternative repository designs are analyzed, both of which would fit into the currently well-characterized site and, therefore, not necessitating any additional site characterization at Yucca Mountain. The two- and three-dimensional models for coupled thermo-hydrological analysis extends from the surface to the water table, covering all the major and subgroup rock layers of the planned repository, as well as formations above and below the repository horizon. A dual-porosity and dual-permeability approach is used to model coupled heat and mass transfer through fracture formations. The waste package heating and ventilation are all assumed to follow those of the current design. The results show that the repository is able to accommodate three times the amount of spent fuel compared to the current design, without extra spatial expansion or exceeding current thermal and hydrological constraints. (authors)

  16. Environmental monitoring and radiation protection programs of Novi Han radioactive waste repository

    International Nuclear Information System (INIS)

    Christoskova, M.; Kostova, M.; Sheherov, L.; Bekiarov, P.; Iovtchev, M.

    2000-01-01

    The system for monitoring and control as an important part of the safety management of the Novi Han Radioactive Waste Repository contains two independent programs: environmental monitoring of the site (controlled area), the restricted access area and the surveillance area (supervised area) of the repository and radiation protection program including personal dosimetric control and indoor dosimetric control of workplaces in the buildings of the repository. The main activities related to the programs implementation are presented

  17. Earth Observation Data Quality Monitoring and Control: A Case Study of STAR Central Data Repository

    Science.gov (United States)

    Han, W.; Jochum, M.

    2017-12-01

    Earth observation data quality is very important for researchers and decision makers involved in weather forecasting, severe weather warning, disaster and emergency response, environmental monitoring, etc. Monitoring and control earth observation data quality, especially accuracy, completeness, and timeliness, is very useful in data management and governance to optimize data flow, discover potential transmission issues, and better connect data providers and users. Taking a centralized near real-time satellite data repository, STAR (Center for Satellite Applications and Research of NOAA) Central Data Repository (SCDR), as an example, this paper describes how to develop new mechanism to verify data integrity, check data completeness, and monitor data latency in an operational data management system. Such quality monitoring and control of large volume satellite data help data providers and managers improve data transmission of near real-time satellite data, enhance its acquisition and management, and overcome performance and management issues to better serve research and development activities.

  18. Interim performance specifications for conceptual waste-package designs for geologic isolation in salt repositories

    International Nuclear Information System (INIS)

    1983-06-01

    The interim performance specifications and data requirements presented apply to conceptual waste package designs for all waste forms which will be isolated in salt geologic repositories. The waste package performance specifications and data requirements respond to the waste package performance criteria. Subject areas treated include: containment and controlled release, operational period safety, criticality control, identification, and waste package performance testing requirements. This document was generated for use in the development of conceptual waste package designs in salt. It will be revised as additional data, analyses, and regulatory requirements become available

  19. Rebar corrosion due to carbonation in structural reinforced concretes for near-surface LLW repositories: A critical failure mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Torok, J

    1995-03-01

    The concrete roof of a near-surface radioactive waste repository is the principle protection against water infiltration and intrusion. The following potential roof failure mechanism is examined: carbon dioxide generated by the biodegradation of organic materials in the repository initiates corrosion of reinforcing steel embedded in the concrete roof. Because the bottom surface of the roof is mostly under tension, it is susceptible to cracking. The migration path for carbon dioxide is through cracks in the concrete between the bottom of the roof and the reinforcing bars. Carbonate corrosion of the reinforcing bars may result in concrete spalling, more extensive rebar corrosion and ultimately structural failure. Attention is brought to this failure mechanism because it has generally been overlooked in repository performance assessments. Literature relevant to the above failure is reviewed. Prerequisites for rebar corrosion are the presence of carbon dioxide and oxygen in the repository gas, high relative humidity and through-cracks in the concrete. High carbon dioxide concentrations and relative humidity are expected in the repository. The oxygen concentration in the repository is expected to be very low, and that is expected to minimize rebar corrosion rates. Cracks are likely to form in locations with high tensile stresses. Healing of the cracks could be a mitigating factor, but based on our analysis, it can not be relied on. To minimize the potential of this failure mechanism occurring with the Intrusion Resistant Underground Structure (IRUS), Canada`s proposed near-surface repository, carbon dioxide from the repository gas will be absorbed by the reactive, porous concrete placed between the waste and the roof. (author). 4 refs.

  20. Rebar corrosion due to carbonation in structural reinforced concretes for near-surface LLW repositories: A critical failure mechanism

    International Nuclear Information System (INIS)

    Torok, J.

    1995-03-01

    The concrete roof of a near-surface radioactive waste repository is the principle protection against water infiltration and intrusion. The following potential roof failure mechanism is examined: carbon dioxide generated by the biodegradation of organic materials in the repository initiates corrosion of reinforcing steel embedded in the concrete roof. Because the bottom surface of the roof is mostly under tension, it is susceptible to cracking. The migration path for carbon dioxide is through cracks in the concrete between the bottom of the roof and the reinforcing bars. Carbonate corrosion of the reinforcing bars may result in concrete spalling, more extensive rebar corrosion and ultimately structural failure. Attention is brought to this failure mechanism because it has generally been overlooked in repository performance assessments. Literature relevant to the above failure is reviewed. Prerequisites for rebar corrosion are the presence of carbon dioxide and oxygen in the repository gas, high relative humidity and through-cracks in the concrete. High carbon dioxide concentrations and relative humidity are expected in the repository. The oxygen concentration in the repository is expected to be very low, and that is expected to minimize rebar corrosion rates. Cracks are likely to form in locations with high tensile stresses. Healing of the cracks could be a mitigating factor, but based on our analysis, it can not be relied on. To minimize the potential of this failure mechanism occurring with the Intrusion Resistant Underground Structure (IRUS), Canada's proposed near-surface repository, carbon dioxide from the repository gas will be absorbed by the reactive, porous concrete placed between the waste and the roof. (author). 4 refs

  1. Alternate measurements of benefit to criticality issues at Hanford

    Energy Technology Data Exchange (ETDEWEB)

    Toffer, H.; Cabrilla, D.E.

    1997-06-01

    Measurements in a critical mass facility, such as the Los Alamos Critical Experiments Facility, could be performed on simulated nuclear waste materials that would provide important critical mass information and concurrently provide a calibration of alternate measurement techniques. In addition to criticality information, the measurements could also provide a better assessment of diluent material/neutron interaction cross sections. An Hanford, large quantities of fissionable materials are dispersed in tanks, fuel storage pools, and in solid waste. Although the fissionable materials are well diluted by a variety of neutron-moderating and -absorbing substances, it is difficult to assess the margin of subcriticality. A number of measurement approaches are proposed that will either help determine fissionable material concentrations, distributions, or provide a direct measure of subcriticality. The methods under consideration involve passive neutron counting, active neutron measurements, pulse neutron applications, neutron noise analyses, and cover gas evaluations. Active neutron measurements can also provide insight into the determination of neutron absorber concentrations. Efforts are underway to test some of the methods in actual waste tank environments and geometries. It is important that these methods be tested and calibrated in a critical mass facility.

  2. Alternate measurements of benefit to criticality issues at Hanford

    International Nuclear Information System (INIS)

    Toffer, H.; Cabrilla, D.E.

    1997-01-01

    Measurements in a critical mass facility, such as the Los Alamos Critical Experiments Facility, could be performed on simulated nuclear waste materials that would provide important critical mass information and concurrently provide a calibration of alternate measurement techniques. In addition to criticality information, the measurements could also provide a better assessment of diluent material/neutron interaction cross sections. An Hanford, large quantities of fissionable materials are dispersed in tanks, fuel storage pools, and in solid waste. Although the fissionable materials are well diluted by a variety of neutron-moderating and -absorbing substances, it is difficult to assess the margin of subcriticality. A number of measurement approaches are proposed that will either help determine fissionable material concentrations, distributions, or provide a direct measure of subcriticality. The methods under consideration involve passive neutron counting, active neutron measurements, pulse neutron applications, neutron noise analyses, and cover gas evaluations. Active neutron measurements can also provide insight into the determination of neutron absorber concentrations. Efforts are underway to test some of the methods in actual waste tank environments and geometries. It is important that these methods be tested and calibrated in a critical mass facility

  3. Long-term maintenance of reducing conditions in a spent nuclear fuel repository. A re-examination of critical factors

    Energy Technology Data Exchange (ETDEWEB)

    Gascoyne, M. [Gascoyne GeoProjects Inc, Pinawa, MB (Canada)

    1999-04-01

    Penetration of oxidising groundwaters to depths of 500 m in a permeable bedrock, over a glacial/interglacial cycle, may compromise the stability of a spent nuclear fuel repository and cause the release and migration towards the surface of actinides and associated fission products. This report examines the potential for the penetration of oxygen (O{sub 2}) to depths of 500 m in a fractured crystalline rock environment, typical of the Fennoscandian Shield. Previous studies performed for the Swedish program of nuclear waste disposal (principally the SITE-94 safety assessment) have indicated that O{sub 2} might reach repository depths during a deglaciation when melt-water from the base of an ice sheet could enter the bedrock, driven by strong hydraulic gradients. This report re-examines aspects of this scenario and finds that: 1. The capacity of flow-path minerals to scavenge O{sub 2} from recharging groundwater may be lower than expected due to a previously unrecognised depletion of Fe(II)-bearing minerals in the active flow-paths in a fractured crystalline rock. 2. Assumptions in the SITE-94 assessment, such as the use of a continental-scale flow model, the lack of structural controls on groundwater flow, a preferred horizontal permeability, and the use of permeabilities to depths of 10 km that are up to two orders of magnitude greater than comparable environments, are disproportionately simplistic and represent an extremely conservative case. 3. Assumptions of a thin, discontinuous permafrost, a warm-based ice sheet, and high-O{sub 2} content melt-water at the repository site are unrealistic and overly conservative. A more realistic scenario, which includes a greater influence of permafrost, a cold based ice sheet, lower bedrock permeabilities and a more-limited, regional-scale flow path, is recommended as being more appropriate for use in the safety assessment. Under this revised scenario, it is believed that O{sub 2} will not penetrate to repository depths over

  4. Long-term maintenance of reducing conditions in a spent nuclear fuel repository. A re-examination of critical factors

    International Nuclear Information System (INIS)

    Gascoyne, M.

    1999-04-01

    Penetration of oxidising groundwaters to depths of 500 m in a permeable bedrock, over a glacial/interglacial cycle, may compromise the stability of a spent nuclear fuel repository and cause the release and migration towards the surface of actinides and associated fission products. This report examines the potential for the penetration of oxygen (O 2 ) to depths of 500 m in a fractured crystalline rock environment, typical of the Fennoscandian Shield. Previous studies performed for the Swedish program of nuclear waste disposal (principally the SITE-94 safety assessment) have indicated that O 2 might reach repository depths during a deglaciation when melt-water from the base of an ice sheet could enter the bedrock, driven by strong hydraulic gradients. This report re-examines aspects of this scenario and finds that: 1. The capacity of flow-path minerals to scavenge O 2 from recharging groundwater may be lower than expected due to a previously unrecognised depletion of Fe(II)-bearing minerals in the active flow-paths in a fractured crystalline rock. 2. Assumptions in the SITE-94 assessment, such as the use of a continental-scale flow model, the lack of structural controls on groundwater flow, a preferred horizontal permeability, and the use of permeabilities to depths of 10 km that are up to two orders of magnitude greater than comparable environments, are disproportionately simplistic and represent an extremely conservative case. 3. Assumptions of a thin, discontinuous permafrost, a warm-based ice sheet, and high-O 2 content melt-water at the repository site are unrealistic and overly conservative. A more realistic scenario, which includes a greater influence of permafrost, a cold based ice sheet, lower bedrock permeabilities and a more-limited, regional-scale flow path, is recommended as being more appropriate for use in the safety assessment. Under this revised scenario, it is believed that O 2 will not penetrate to repository depths over the next 100,000 years

  5. Salt Repository emplacement mode evaluation and selection: Final report

    International Nuclear Information System (INIS)

    1988-03-01

    This document describes the decision analysis performed to evaluate and compare the emplacement mode for the Salt Repository. The study was commissioned to recommend one emplacement mode to the Salt Repository Project Office using multi-attribute decision analysis. The nature of the decision required analysis of uncertain outcomes and conflicting attributes and offers a high degree of objectivity for these types of decisions since the decision model is structured to allow only the facts to enter into the final decision. The analysis requires an explicit definition of the attributes used to evaluate the alternative (e.g., cost, safety, environmental impact), the definition of a utility function over the attributes which incorporated both risk attitudes and trade-offs between attributes, and the probability distribution over the outcomes that would result from the selection of one alternative over the other. The decision process is described and results are given. A simulation model was developed to evaluate the probability distributions over the attributes. This report documents logic, inputs and results of this model. Final ranking of alternatives is given. Extensive technical backup documentation is included in the appendices to provide the quantitative basis for this decision. 5 refs., 2 figs., 8 tabs

  6. Ethical considerations surrounding nuclear waste repository siting and mitigation

    International Nuclear Information System (INIS)

    Peters, T.F.

    1983-01-01

    The potential long-term health and safety effects of the nuclear materials stored in repositories, the extremely long periods of time over which such materials may be dangerous, and the equity implications of the siting of a repository in any given area are unlike the issues involved in other large-scale projects. They involve major philosophical issues basic to human perspectives on social relationships and on insuring the future of mankind. Safety and permanence are the two basic criteria for determining whether a waste proposal is satisfactory. This chapter takes the approach of public (or micro) ethics, whose task is to 1) articulate and clarify public values relevant to a problem, 2) identify and evaluate public options, and 3) rank alternatives in some order of ethical preferability. It addresses the four major repository-related issues: uncertainty and risks, geographic equity, intergenerational ethics, and implementation ethics

  7. Learning Object Repositories

    Science.gov (United States)

    Lehman, Rosemary

    2007-01-01

    This chapter looks at the development and nature of learning objects, meta-tagging standards and taxonomies, learning object repositories, learning object repository characteristics, and types of learning object repositories, with type examples. (Contains 1 table.)

  8. A methodology for evaluating alternative sites for a near-surface radioactive waste repository

    International Nuclear Information System (INIS)

    Watson, S.R.; Brownlow, S.A.

    1986-02-01

    This report addresses the issue of constructing an evaluation procedure for a near-surface radioactive waste repository. It builds on earlier work of the authors, and describes a basis for a practicable methodology for assessing the relative merits of different sites. (author)

  9. The role of libraries in open access institutional repositories.

    Directory of Open Access Journals (Sweden)

    Tony Hernández Peréz

    2008-02-01

    Full Text Available Nowadays, there are more and more institutional repositories in Spain, as in a large number of countries all over the world, which contains thousands of digital objects in open access, full-text, no-charge and available to free download, print or copy. Nearly every repository is managed and mantained by the library services of the institution they serve. This article explains the reasons for the crisis in the scholarly communication model, the alternative model based on open access to scholarly publication, and the crucial role that the libraries can play in the development of their own digital collections, a challenge and a chance that they can't miss.

  10. Nuclear safety requirements for upgrading the National Repository for Radioactive Wastes-Baita Bihor

    International Nuclear Information System (INIS)

    Vladescu, Gabriela; Necula, Daniela

    2000-01-01

    The upgrading project of National Repository for Radioactive Wastes-Baita Bihor is based on the integrated concept of nuclear safety. Its ingredients are the following: A. The principles of nuclear safety regarding the management of radioactive wastes and radioprotection; B. Safety objectives for final disposal of low- and intermediate-level radioactive wastes; C. Safety criteria for final disposal of low- and intermediate-level radioactive wastes; D. Assessment of safety criteria fulfillment for final disposal of low- and intermediate-level radioactive wastes. Concerning the nuclear safety in radioactive waste management the following issues are considered: population health protection, preventing transfrontier contamination, future generation radiation protection, national legislation, control of radioactive waste production, interplay between radioactive waste production and management, radioactive waste repository safety. The safety criteria of final disposal of low- and intermediate-level radioactive wastes are discussed by taking into account the geological and hydrogeological configuration, the physico-chemical and geochemical characteristics, the tectonics and seismicity conditions, extreme climatic potential events at the mine location. Concerning the requirements upon the repository, the following aspects are analyzed: the impact on environment, the safety system reliability, the criticality control, the filling composition to prevent radioactive leakage, the repository final sealing, the surveillance. Concerning the radioactive waste, specific criteria taken into account are the radionuclide content, the chemical composition and stability, waste material endurance to heat and radiation. The waste packaging criteria discussed are the mechanical endurance, materials toughness and types as related to deterioration caused by handling, transportation, storing or accidents. Fulfillment of safety criteria is assessed by scenarios analyses and analyses of

  11. Design analysis of engineered alternatives for the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Myers, J.; Djordjevic, S.; Adams, M.; Spangler, L.; Valdez, J.; Vetter, D.; Drez, P.

    1991-01-01

    The effectiveness of several engineered alternatives, designed to enhance the performance of the Waste Isolation Pilot Plant (WIPP), were evaluated relative to the performance of the baseline design. This evaluation was performed using a computer program referred to as the Design Analysis Model which couples salt creep closure, brine inflow, gas generation and dissipation to realistically simulate these interrelated processes over a 10,000 year period following the decommissioning of the repository. Analyses of the baseline design and nine alternative designs were performed for the undisturbed repository conditions, as well as three human intrusion events. Improvements in repository performance of up to four orders of magnitude were predicted for various engineered alternative waste forms. 6 refs., 8 figs., 1 tab

  12. Summary of repository siting models. Final report

    International Nuclear Information System (INIS)

    Thomas, S.D.; Ross, B.; Mercer, J.W.

    1982-07-01

    This report is the first in a series of reports that will provide critical reviews and summaries of computer programs that can be used to analyze the potential performance of a high-level radioactive waste repository. The computer programs identified address the following phenomena: saturated and unsaturated subsurface flow, heat transport, solute transport, surface water runoff, geomechanical interactions, and geochemical interactions. The report identifies 183 computer programs that can be used to analyze a repository site and provides a summary description of 31 computer programs. The summary descriptions can be used: to assist in code evaluation, to facilitate code comparison, to determine applicability of codes to specific problems, to identify code deficiencies, and to provide a screening mechanism for code selection

  13. Comparison of spent fuel management fee collection alternatives

    International Nuclear Information System (INIS)

    White, M.K.; Engel, R.L.

    1979-01-01

    Five alternative methods for recovering the costs of spent fuel management were evaluated. These alternatives consist of collecting the fee for various components of spent fuel management cost (AFR basin storage, transportation from AFR basin to the repository, packaging, repository, R and D, and government overhead) at times ranging from generation of power to delivery of the spent fuel to the government. The five fee collection mechanisms were analyzed to determine how well they serve the interests of the public and the electricity ratepayer

  14. Repository Rodeo Redux

    CERN Document Server

    Anez, Melissa; Donohue, Tim; Fyson, Will; Simko, Tibor; Wilcox, David

    2017-01-01

    You’ve got more repository questions and we’ve got more answers! Last year’s Repository Rodeo panel was a huge success, so we’re taking the show on the road to Brisbane for OR2017. Join representatives from the DSpace, Eprints, Fedora, Hydra, and Islandora communities as we (briefly) explain what each of our repositories actually does. We'll also talk about the directions of our respective technical and community developments, and related to the conference theme of Open: Innovation Knowledge Repositories, offer brief observations about the latest, most promising and/or most surprising innovations in our space. This panel will be a great opportunity for newcomers to Open Repositories to get a crash course on the major repository options and meet representatives from each of their communities. After a brief presentation from each representative, we'll open the session up for questions from the audience.

  15. Review of durability of cementitious engineered barriers in repository environments

    International Nuclear Information System (INIS)

    Parrott, L.J.; Lawrence, C.D.

    1992-01-01

    This report is concerned with the durability of cementitious engineered barriers in a repository for low and intermediate level nuclear waste. Following the introduction the second section of the review identifies the environmental conditions associated with a deep, hard rock repository for ILW and LLW that are relevant to the durability of cementitious barriers. Section three examines the microstructure and macrostructure of cementitious materials and considers the physical and chemical processes of radionuclide immobilization. Potential repository applications and compositions of cementitious materials are reviewed in Section four. The main analysis of durability is dealt with in Section five. The different types of cementitious barrier are considered separately and their most probable modes of degradation are analysed. Concluding remarks that highlight critical technical matters are given in Section six. (author)

  16. Performance assessment of Mochovce repository

    Energy Technology Data Exchange (ETDEWEB)

    Mrskova, A; Hanusik, V [Dept. of Accident Management and Risk Assessment, Vyskumny Ustav Jadrovych Elektrarni, Trnava (Slovakia)

    2000-07-01

    The near-surface disposal site at Mochovce is designed for low-level and intermediate level radioactive waste. It is a vault-type concrete structure housing the reinforced concrete containers as the final waste packages. This paper shortly presents the long-term safety analysis methods applied for the post-closure phase of the repository. The main aim of paper is description of the philosophy of analysis, development of the scenarios, their modeling and comparing of the results of normal evolution scenario, alternative scenario and intruders scenario for some radionuclides. (author)

  17. Performance assessment of Mochovce repository

    International Nuclear Information System (INIS)

    Mrskova, A.; Hanusik, V.

    2000-01-01

    The near-surface disposal site at Mochovce is designed for low-level and intermediate level radioactive waste. It is a vault-type concrete structure housing the reinforced concrete containers as the final waste packages. This paper shortly presents the long-term safety analysis methods applied for the post-closure phase of the repository. The main aim of paper is description of the philosophy of analysis, development of the scenarios, their modeling and comparing of the results of normal evolution scenario, alternative scenario and intruders scenario for some radionuclides. (author)

  18. Surface-type repository for low and intermediate level radioactive waste in the Republic of Croatia

    International Nuclear Information System (INIS)

    Kucar-Dragicevic, S.; Zarkovic, V.; Subasic, D.

    1995-01-01

    The low-level intermediate-level (LL/IL) radioactive waste repository siting and construction project is one of the activities related to establishing the rad waste management system in the Republic of Croatia. The repository project design is one in an array of project activities which also include the site selection procedure and public attitude issues. The prepared design documentation gives technical, safety and financial background relevant for making a final decision on the waste disposal type, and it includes the technological, mechanical, civil and financial documentation on the preliminary/basic design level. During the last few years, the preliminary design has been prepared and safety assessment conducted for the tunnel-type LL/IL rad waste repository. As the surface-type repository is one of alternatives for final disposal the design documentation for that repository type was prepared during 1994. (author)

  19. Probabilistic Criticality Consequence Evaluation

    International Nuclear Information System (INIS)

    P. Gottlieb; J.W. Davis; J.R. Massari

    1996-01-01

    This analysis is prepared by the Mined Geologic Disposal System (MGDS) Waste Package Development (WPD) department with the objective of providing a comprehensive, conservative estimate of the consequences of the criticality which could possibly occur as the result of commercial spent nuclear fuel emplaced in the underground repository at Yucca Mountain. The consequences of criticality are measured principally in terms of the resulting changes in radionuclide inventory as a function of the power level and duration of the criticality. The purpose of this analysis is to extend the prior estimates of increased radionuclide inventory (Refs. 5.52 and 5.54), for both internal and external criticality. This analysis, and similar estimates and refinements to be completed before the end of fiscal year 1997, will be provided as input to Total System Performance Assessment-Viability Assessment (TSPA-VA) to demonstrate compliance with the repository performance objectives

  20. A GoldSim Based Biosphere Assessment Model for a HLW Repository

    International Nuclear Information System (INIS)

    Lee, Youn-Myoung; Hwang, Yong-Soo; Kang, Chul-Hyung

    2007-01-01

    To demonstrate the performance of a repository, the dose exposure to a human being due to nuclide releases from a repository should be evaluated and the results compared to the dose limit presented by the regulatory bodies. To evaluate a dose rate to an individual due to a long-term release of nuclides from a HLW repository, biosphere assessment models and their implemented codes such as ACBIO1 and ACBIO2 have been developed with the aid of AMBER during the last few years. BIOMASS methodology has been adopted for a HLW repository currently being considered in Korea, which has a similar concept to the Swedish KBS-3 HLW repository. Recently, not just only for verifying the purpose for biosphere assessment models but also for varying the possible alternatives to assess the consequences in a biosphere due to a HLW repository, another version of the assessment modesl has been newly developed in the frame of development programs for a total system performance assessment modeling tool by utilizing GoldSim. Through a current study, GoldSim approach for a biosphere modeling is introduced. Unlike AMBER by which a compartment scheme can be rather simply constructed with an appropriate transition rate between compartments, GoldSim was designed to facilitate the object-oriented modules by which specific models can be addressed in an additional manner, like solving jig saw puzzles

  1. Commercial nuclear waste repository in basalt

    International Nuclear Information System (INIS)

    Hardy, M.P.; Patricio, J.G.; Heley, W.H.

    1980-06-01

    The Basalt Waste Isolation Project (BWIP) is an ongoing research and engineering effort being conducted by Rockwell Hanford Operations (Rockwell), which is under contract to the US Department of Energy. The objectives of this program are to assess the feasibility of and to provide the technology needed to design and construct a licensed commercial nuclear waste repository in the deep basalt formations underlying the Hanford Site. An extensive preconceptual design effort was undertaken during 1979 to develop a feasible concept that could serve as a reference design for both surface and underground facilities. The preconceptual design utilized existing technology to the greatest extent possible to offer a system design that could be utilized in establishing schedule and cost baseline data, recommend alternatives that require additional study, and develop basic design requirements that would allow evolution of the design process prior to the existence of legislated criteria. This paper provides a description of the concept developed for the subsurface aspects of this nuclear waste repository

  2. Performance assessment development for a LILW repository in Slovenia

    International Nuclear Information System (INIS)

    Zeleznik, N.; Mele, I.

    2001-01-01

    Simultaneously with the site selection process for a low and intermediate level radioactive waste (LILW) repository, the preliminary assessment of the influence of the specific disposal concept on the environment and on the population was developed. The performance assessment team, organized in 1997 by ARAO, prepared several basic studies in order to clarify the objectives of the performance and safety assessment (PA/SA) procedure. In 1999 also the first performance assessment of two safety cases (surface and underground) for generic site for a LILW repository was realized. In the year 2000 activities on PA/SA analyses continued. A systematic, generic list was prepared of all possible features, events and processes (FEP list) predictable for surface or underground LILW disposal in Slovenia. Recommended and selected were the most reliable scenarios with conceptual models for LILW disposal in normal and altered evolution conditions. New verification of the obtained results was done with more powerful and accurate models for the surface repository over an aquifer of lower water permeability and an underground repository in a plastic rock. The results for both generic cases under normal evolution scenarios showed that there is a negligible dose influence on members of the critical population due to the migration of radionuclides from the foreseen LILW repository. The results of the already performed work as well as plans for the future activities are presented in the paper.(author)

  3. NWTS conceptual reference repository description (CRRD). Volume 1. Summary

    International Nuclear Information System (INIS)

    1981-05-01

    This report is a Conceptual Reference Repository Description (CRRD) for the terminal storage of spent, unreprocessed fuel assemblies and low-level transuranic waste. It is based on the following three previously prepared conceptual design reports: National Waste Terminal Storage in a Bedded Salt Formation for Spent Unreprocessed Fuel (NWTS-R2), prepared by Kaiser Engineers; National Waste Terminal Storage Repository Number 1 (NWTS-R1), prepared by Stearns-Roger; Spent Fuel Receiving and Packaging Facility Conceptual Design, prepared by Rockwell Hanford Operations and Kaiser Engineers. The CRRD is not itself a conceptual design report, but combines the key features of the above three reports into a description of a reference repository. This description is to be used as a basis for the preparation of a preliminary information report for the repositories. The CRRD discusses from a conceptual engineering standpoint the structures, systems, equipment, and operations necessary to (1) receive unreprocessed spent fuel assemblies via standard shipping casks, (2) offload these assemblies, (3) place the assemblies in canisters, (4) transport the canisters to underground storage locations in the salt dome, and (5) place these canisters in terminal storage. The CRRD also elaborates on the concepts for the retrieval and recovery of the spent fuel after burial; describes the development of the shafts and the underground areas,as well as the supporting operational utility and administrative features of the repository; and discusses the impacts on the reference repository of (1) changes in the waste package concept, (2) dry receiving and dry temporary storage of waste, (3) terminal storage of reprocessing waste, and (4) alternative underground development schemes

  4. LIFE Materials: Fuel Cycle and Repository Volume 11

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, H; Blink, J A

    2008-12-12

    The fusion-fission LIFE engine concept provides a path to a sustainable energy future based on safe, carbon-free nuclear power with minimal nuclear waste. The LIFE design ultimately offers many advantages over current and proposed nuclear energy technologies, and could well lead to a true worldwide nuclear energy renaissance. When compared with existing and other proposed future nuclear reactor designs, the LIFE engine exceeds alternatives in the most important measures of proliferation resistance and waste minimization. The engine needs no refueling during its lifetime. It requires no removal of fuel or fissile material generated in the LIFE engine. It leaves no weapons-attractive material at the end of life. Although there is certainly a need for additional work, all indications are that the 'back end' of the fuel cycle does not to raise any 'showstopper' issues for LIFE. Indeed, the LIFE concept has numerous benefits: (1) Per unit of electricity generated, LIFE engines would generate 20-30 times less waste (in terms of mass of heavy metal) requiring disposal in a HLW repository than does the current once-through fuel cycle. (2) Although there may be advanced fuel cycles that can compete with LIFE's low mass flow of heavy metal, all such systems require reprocessing, with attendant proliferation concerns; LIFE engines can do this without enrichment or reprocessing. Moreover, none of the advanced fuel cycles can match the low transuranic content of LIFE waste. (3) The specific thermal power of LIFE waste is initially higher than that of spent LWR fuel. Nevertheless, this higher thermal load can be managed using appropriate engineering features during an interim storage period, and could be accommodated in a Yucca-Mountain-like repository by appropriate 'staging' of the emplacement of waste packages during the operational period of the repository. The planned ventilation rates for Yucca Mountain would be sufficient for LIFE waste

  5. LIFE Materials: Fuel Cycle and Repository Volume 11

    International Nuclear Information System (INIS)

    Shaw, H.; Blink, J.A.

    2008-01-01

    The fusion-fission LIFE engine concept provides a path to a sustainable energy future based on safe, carbon-free nuclear power with minimal nuclear waste. The LIFE design ultimately offers many advantages over current and proposed nuclear energy technologies, and could well lead to a true worldwide nuclear energy renaissance. When compared with existing and other proposed future nuclear reactor designs, the LIFE engine exceeds alternatives in the most important measures of proliferation resistance and waste minimization. The engine needs no refueling during its lifetime. It requires no removal of fuel or fissile material generated in the LIFE engine. It leaves no weapons-attractive material at the end of life. Although there is certainly a need for additional work, all indications are that the 'back end' of the fuel cycle does not to raise any 'showstopper' issues for LIFE. Indeed, the LIFE concept has numerous benefits: (1) Per unit of electricity generated, LIFE engines would generate 20-30 times less waste (in terms of mass of heavy metal) requiring disposal in a HLW repository than does the current once-through fuel cycle. (2) Although there may be advanced fuel cycles that can compete with LIFE's low mass flow of heavy metal, all such systems require reprocessing, with attendant proliferation concerns; LIFE engines can do this without enrichment or reprocessing. Moreover, none of the advanced fuel cycles can match the low transuranic content of LIFE waste. (3) The specific thermal power of LIFE waste is initially higher than that of spent LWR fuel. Nevertheless, this higher thermal load can be managed using appropriate engineering features during an interim storage period, and could be accommodated in a Yucca-Mountain-like repository by appropriate 'staging' of the emplacement of waste packages during the operational period of the repository. The planned ventilation rates for Yucca Mountain would be sufficient for LIFE waste to meet the thermal constraints of

  6. A Study on Establishment of Buffer Zone of Radioactive Waste Repository

    International Nuclear Information System (INIS)

    Yoon, Jeong Hyoun; Park, Joo Wan; Ju, Min Su; Kim, Chang Lak; Park, Jin Baek

    2008-01-01

    A new proposed repository has a final capacity of 800,000 drums radioactive waste. Most of foreign repositories have a general practice of segregating control zones which mainly contributes to classification of degree of control, whether it is called buffer zone or not. Domestic regulatory requirements of establishment of buffer zone in a repository are not much different from those of nuclear power plants for operation period, in which satisfactory design objective or performance objective is the most important factor in determination of the buffer zone. The meaning of buffer zone after closure is a minimum requested area which can prevent inadvertent intruders from leading to non-allowable exposure during institutional control period. Safety assessment with drinking well scenario giving rise to the highest probability of exposure among the intruder's actions can verify fulfillment of the buffer zone which is determined by operational safety of the repository. At present. for the repository to be constructed in a few years, the same procedure and concept as described in this paper are applied that can satisfy regulatory requirements and radiological safety as well. However, the capacity of the repository will be stepwise extended upto 800,000 drums, consequently its layout will be varied too. Timely considerations will be necessary for current boundary of the buffer zone which has been established on the basis of 100,000 drums disposal.

  7. Handling encapsulated spent fuel in a geologic repository environment

    International Nuclear Information System (INIS)

    Ballou, L.B.

    1983-02-01

    In support of the Spent Fuel Test-Climate at the U.S. Department of Energy's Nevada Test Site, a spent-fuel canister handling system has been designed, deployed, and operated successfully during the past five years. This system transports encapsulated commercial spent-fuel assemblies between the packaging facility and the test site (approx. 100 km), transfers the canisters 420 m vertically to and from a geologic storage drift, and emplaces or retrieves the canisters from the storage holes in the floor of the drift. The spent-fuel canisters are maintained in a fully shielded configuration at all times during the handling cycle, permitting manned access at any time for response to any abnormal conditions. All normal operations are conducted by remote control, thus assuring as low as reasonably achievable exposures to operators; specifically, we have had no measurable exposure during 30 canister transfer operations. While not intended to be prototypical of repository handling operations, the system embodies a number of concepts, now demonstrated to be safe, reliable, and economical, which may be very useful in evaluating full-scale repository handling alternatives in the future. Among the potentially significant concepts are: Use of an integral shielding plug to minimize radiation streaming at all transfer interfaces. Hydraulically actuated transfer cask jacking and rotation features to reduce excavation headroom requirements. Use of a dedicated small diameter (0.5 m) drilled shaft for transfer between the surface and repository workings. A wire-line hoisting system with positive emergency braking device which travels with the load. Remotely activated grapples - three used in the system - which are insensitive to load orientation. Rail-mounted underground transfer vehicle operated with no personnel underground

  8. Geoscience data base handbook for modeling a nuclear waste repository. Volume 1

    International Nuclear Information System (INIS)

    Isherwood, D.

    1979-12-01

    This handbook contains reference information on parameters that should be considered in analyzing or modeling a proposed nuclear waste repository site. Only those parameters and values that best represent the natural environment are included. Rare extremes are avoided. Where laboratory and field data are inadequate, theoretical treatments and informed engineering judgements are presented. Volume 1 contains a data base on salt as a repository medium. Chapters on the geology of bedded and dome salt, the geomechanics of salt, hydrology, geochemistry, natural and man-made features, and seismology provide compiled data and related information useful for studying a proposed repository in salt. These and other data will be needed to derive generic deep geologic modeling parameters and will also serve as background for the verification of source data that may be presented in licensing applications for nuclear waste repositories. Volume 2 is the result of a scoping study for a data base on the geology, geomechanics, and hydrology of shale, granite, and basalt as alternative repository media. Except for the geomechanics of shale, most of the sections contain relatively complete compilations of the available data, as well as discussions of the properties that are unique to each rock type

  9. Backfilling techniques and materials in underground excavations: Potential alternative backfill materials in use in Posiva's spent fuel repository concept

    International Nuclear Information System (INIS)

    Dixon, D.A.; Keto, P.

    2009-05-01

    A variety of geologic media options have been proposed as being suitable for safely and permanently disposing of spent nuclear fuel or fuel reprocessing wastes. In Finland the concept selected is construction of a deep repository in crystalline rock (Posiva 1999, 2006; SKB 1999), likely at the Olkiluoto site (Posiva 2006). Should that site prove suitable, excavation of tunnels and several vertical shafts will be necessary. These excavations will need to be backfilled and sealed as emplacement operations are completed and eventually all of the openings will need to be backfilled and sealed. Clay-based materials were selected after extensive review of materials options and the potential for practical implementation in a repository and work over a 30+ year period has led to the development of a number of workable clay-based backfilling options, although discussion persists as to the most suitable clay materials and placement technologies to use. As part of the continuous process of re-evaluating backfilling options in order to provide the best options possible, placement methods and materials that have been given less attention have been revisited. Primary among options that were and continue to be evaluated as a potential backfill are cementitious materials. These materials were included in the list of candidate materials initially screened in the late 1970's for use in repository backfilling. Conventional cement-based materials were quickly identified as having some serious technical limitations with respect their ability to fulfil the identified requirements of backfill. Concerns related to their ability to achieve the performance criteria defined for backfill resulted in their exclusion from large-scale use as backfill in a repository. Development of new, less chemically aggressive cementitious materials and installation technologies has resulted in their re-evaluation. Concrete and cementitious materials have and are being developed that have chemical, durability

  10. Rolling Deck to Repository II: Getting Control of Provenance and Quality

    Science.gov (United States)

    Miller, S. P.; Arko, R.; Chandler, C. L.; Clark, P. D.; Neiswender, C.

    2008-12-01

    Data are now being re-used by a far wider circle of researchers and students than ever before, across a broader range of disciplines. Before, during, and after a field program, the exchange and merging of information is a dynamic, iterative and sometimes anonymous process that may occur years, or decades, after the data were initially acquired. Collaborative steps are currently being taken toward a prototype data discovery system that can be extended to the entire NSF-supported academic research fleet, including both large and small operations. With emerging shipboard Internet capabilities, near real-time transport of selected data from the rolling deck to a repository can become a reality. Much of the effort is being devoted to data preservation and access, to the identification of standard products, and to the generation of appropriate metadata, with a streamlined methodology that can be adopted by a wide range of vessel operating institutions. Beyond the challenge of just finding data, currently researchers and students struggle repeatedly to make sense of downloaded data objects. Across institutions there are wide variations in quality control procedures, most commonly none, and virtually no external communication of the history of transformations applied to a data set. For example, the status of corrections for sound velocity or roll-bias, or beampoint editing for multibeam swath seafloor mapping sonar systems are often challenging to experts and baffling to users from other disciplines. With greater re-use of data comes the greater likelihood of interpretation of artifacts as features. Tracking data provenance and quality is a problem today, and the situation will become more critical as data are more widely and rapidly disseminated. We will identify quality control criteria for standard shipboard data products, and existing tools for quality assessment with automation potential (or lack thereof). We invite discussion of an XML institutional quality

  11. SPI Project Criticality Task Force initial review and assessment

    International Nuclear Information System (INIS)

    McKinley, K.B.; Cannon, J.W.; Marsden, R.S.; Worle, H.A.

    1980-03-01

    The Slagging Pyrolysis Incinerator (SPI) Facility is being developed to process transuranic waste stored and buried at the Idaho National Engineering Laboratory (INEL) into a chemically inert, physically stable, basalt-like residue acceptable for a Federal Repository. A task force was established by the SPI Project Division to review and assess all aspects of criticality safety for the SPI Facility. This document presents the initial review, evaluations, and recommendations of the task force and includes the following: background information on waste characterization, and criticality control approaches and philosophies, a description of the SPI Facility Waste Processing Building, a review and assessment of potentially relevant codes and regulations; a review and assessment of the present state of criticality and assaying/monitoring studies, and recommendations for changes in and additions to these studies. The review and assessment of potentially relevant codes and regulations indicate that ERDAM 0530, Nuclear Criticality Safety should be the controlling document for criticality safety for the SPI Project. In general, the criticality control approaches and philosophies for the SPI Project comply with this document

  12. Towards Interoperable Preservation Repositories: TIPR

    Directory of Open Access Journals (Sweden)

    Priscilla Caplan

    2010-07-01

    Full Text Available Towards Interoperable Preservation Repositories (TIPR is a project funded by the Institute of Museum and Library Services to create and test a Repository eXchange Package (RXP. The package will make it possible to transfer complex digital objects between dissimilar preservation repositories.  For reasons of redundancy, succession planning and software migration, repositories must be able to exchange copies of archival information packages with each other. Every different repository application, however, describes and structures its archival packages differently. Therefore each system produces dissemination packages that are rarely understandable or usable as submission packages by other repositories. The RXP is an answer to that mismatch. Other solutions for transferring packages between repositories focus either on transfers between repositories of the same type, such as DSpace-to-DSpace transfers, or on processes that rely on central translation services.  Rather than build translators between many dissimilar repository types, the TIPR project has defined a standards-based package of metadata files that can act as an intermediary information package, the RXP, a lingua franca all repositories can read and write.

  13. Project on Alternative Systems Study - PASS. Final report

    International Nuclear Information System (INIS)

    1992-10-01

    Alternative repository systems for deep disposal of spent fuel and different types of canisters are studied regarding technical aspects in Project on Alternative System Study (PASS). The objective is to present a ranking of repository systems as well as of canister types for each system. The studies and compared systems are: KBS-3, Medium Long Tunnels (MLH), Long tunnels (VLH) and Deep Boreholes (VDH). For KBS-3 and MLH five canister types are compared (copper/steel, copper/lead, copper (HIP), steel/lead and steel), for VLH two types (copper/steel and steel), and for VDH three types (titanium/concrete with non-consolidated fuel assemblies, titanium/concrete with consolidated assemblies and copper (HIP) with non-consolidated assemblies). The comparison is separated into three sub-comparisons (Technology, Long-term performance and safety, and Costs), which eventually are merged into one ranking. With respect to canister alternatives the result is that the copper/steel canister is ranked first for KBS-3, MLH and VLH, while the titanium/concrete canister is ranked first for VDH (non-consolidated as well as consolidated assemblies. With these canister alternatives the merged ranking of repository systems results in placing KBS-3 slightly in front of MLH. VLH comes thereafter and VDH last. (32 refs.)

  14. Cancer Epidemiology Data Repository (CEDR)

    Science.gov (United States)

    In an effort to broaden access and facilitate efficient data sharing, the Epidemiology and Genomics Research Program (EGRP) has created the Cancer Epidemiology Data Repository (CEDR), a centralized, controlled-access database, where Investigators can deposit individual-level de-identified observational cancer datasets.

  15. Trustworthy Digital Repositories: Building Trust the Old Fashion Way, EARNING IT.

    Science.gov (United States)

    Kinkade, D.; Chandler, C. L.; Shepherd, A.; Rauch, S.; Groman, R. C.; Wiebe, P. H.; Glover, D. M.; Allison, M. D.; Copley, N. J.; Ake, H.; York, A.

    2016-12-01

    There are several drivers increasing the importance of high quality data management and curation in today's research process (e.g., OSTP PARR memo, journal publishers, funders, academic and private institutions), and proper management is necessary throughout the data lifecycle to enable reuse and reproducibility of results. Many digital data repositories are capable of satisfying the basic management needs of an investigator looking to share their data (i.e., publish data in the public domain), but repository services vary greatly and not all provide mature services that facilitate discovery, access, and reuse of research data. Domain-specific repositories play a vital role in the data curation process by working closely with investigators to create robust metadata, perform first order QC, and assemble and publish research data. In addition, they may employ technologies and services that enable increased discovery, access, and long-term archive. However, smaller domain facilities operate in varying states of capacity and curation ability. Within this repository environment, individual investigators (driven by publishers, funders, or institutions) need to find trustworthy repositories for their data; and funders need to direct investigators to quality repositories to ensure return on their investment. So, how can one determine the best home for valuable research data? Metrics can be applied to varying aspects of data curation, and many credentialing organizations offer services that assess and certify the trustworthiness of a given data management facility. Unfortunately, many of these certifications can be inaccessible to a small repository in cost, time, or scope. Are there alternatives? This presentation will discuss methods and approaches used by the Biological and Chemical Oceanography Data Management Office (BCO-DMO; a domain-specific, intermediate digital data repository) to demonstrate trustworthiness in the face of a daunting accreditation landscape.

  16. Safety Assessment for a KBS-3H spent nuclear fuel repository at Olkiluoto

    International Nuclear Information System (INIS)

    Smith, P.; Neall, F.; Snellman, M.; Pastina, B.; Hjerpe, T.; Nordman, H.; Johnson, L.

    2007-12-01

    canister failure may be affected by perturbations due, for example, to the presence of steel components external to the canister in the present KBS-3H reference design. These will corrode over time and interact with the bentonite buffer, affecting its transport properties. In spite of such perturbations, calculated releases are limited and comply with Finnish regulatory criteria in the cases considered. The present safety assessment has some important limitations. In particular, the analysis of a limited range of assessment cases with highly simplified models, especially of the geosphere, is not considered sufficient to test whether the current KBS-3H design at the Olkiluoto site satisfies all relevant regulatory guidelines. Further limitations are that the feasibility of implementing the current reference design has been assumed, even though several design issues remain to be addressed. Furthermore, only single canister failure cases have been considered. Nevertheless, it can be concluded, based on the present safety assessment, that the KBS-3H design alternative offers potential for the full demonstration of safety for a repository at Olkiluoto site and for the demonstration that it fulfills the same long-term safety requirements as KBS-3V. Remaining critical scientific and design issues are highlighted in this report. These include the further development of the DAWE (Drainage, Artifical Watering and air Evacuation) design alternative to avoid uncertainties associated with the buffer saturation process, as well as studies of iron / bentonite interaction and the possible use of materials such as titanium in place of steel for some system components. This report has also been published as a SKB report, SKB R-08-39. (orig.)

  17. Repositories; Repositorios

    Energy Technology Data Exchange (ETDEWEB)

    Freire, Carolina Braccini; Tello, Cledola Cassia Oliveira de [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)]. E-mails: cbf@cdtn.br; tellocc@cdtn.br

    2007-11-15

    The use of the nuclear energy is increasing in all areas. Then the radioactive waste management is in continuous development to comply the national and international established requirements. The final objective is to assure that it will not have any contamination of the public or the environmental, and that the exposition doses will be lower than the radiological protection limits. The multi barrier concept for the repository is internationally recognized. Among the repository types, the most used are: near surface, geological formations and of deposition in rock cavities. This article explains the concept and the types of repository and gives some examples of them. (author)

  18. Characteristics of potential repository wastes

    International Nuclear Information System (INIS)

    Notz, K.J.

    1989-01-01

    The Office of Civilian Radioactive Waste Management (OCRWM) is responsible for the spent fuels and other wastes that will be disposed of in a geologic repository. The two major sources of these materials are commercial light-water reactor (LWR) spent fuel and immobilized high-level waste (HLW). Other wastes that may require long-term isolation include non-LWR spent fuels and miscellaneous sources such as activated metals. Detailed characterizations are required for all of these potential repository wastes. These characterizations include physical, chemical, and radiological properties. The latter must take into account decay as a function of time. This information has been extracted from primary data sources, evaluated, and assembled in a Characteristics Data Base which provides data in four formats: hard copy standard reports, menu-driven personal computer (PC) data bases, program-level PC data bases, and mainframe computer files. The Characteristics Data Base provides a standard set of self-consistent data to the various areas of responsibility including systems integration and waste stream analysis, storage, transportation, and geologic disposal. The data will be used for design studies, evaluation of alternatives, and system optimization by OCRWM and supporting contractors. 7 refs., 5 figs., 7 tabs

  19. Assuring the Quality of Agricultural Learning Repositories: Issues for the Learning Object Metadata Creation Process of the CGIAR

    Science.gov (United States)

    Zschocke, Thomas; Beniest, Jan

    The Consultative Group on International Agricultural Re- search (CGIAR) has established a digital repository to share its teaching and learning resources along with descriptive educational information based on the IEEE Learning Object Metadata (LOM) standard. As a critical component of any digital repository, quality metadata are critical not only to enable users to find more easily the resources they require, but also for the operation and interoperability of the repository itself. Studies show that repositories have difficulties in obtaining good quality metadata from their contributors, especially when this process involves many different stakeholders as is the case with the CGIAR as an international organization. To address this issue the CGIAR began investigating the Open ECBCheck as well as the ISO/IEC 19796-1 standard to establish quality protocols for its training. The paper highlights the implications and challenges posed by strengthening the metadata creation workflow for disseminating learning objects of the CGIAR.

  20. Controlled soil warming powered by alternative energy for remote field sites.

    Science.gov (United States)

    Johnstone, Jill F; Henkelman, Jonathan; Allen, Kirsten; Helgason, Warren; Bedard-Haughn, Angela

    2013-01-01

    Experiments using controlled manipulation of climate variables in the field are critical for developing and testing mechanistic models of ecosystem responses to climate change. Despite rapid changes in climate observed in many high latitude and high altitude environments, controlled manipulations in these remote regions have largely been limited to passive experimental methods with variable effects on environmental factors. In this study, we tested a method of controlled soil warming suitable for remote field locations that can be powered using alternative energy sources. The design was tested in high latitude, alpine tundra of southern Yukon Territory, Canada, in 2010 and 2011. Electrical warming probes were inserted vertically in the near-surface soil and powered with photovoltaics attached to a monitoring and control system. The warming manipulation achieved a stable target warming of 1.3 to 2 °C in 1 m(2) plots while minimizing disturbance to soil and vegetation. Active control of power output in the warming plots allowed the treatment to closely match spatial and temporal variations in soil temperature while optimizing system performance during periods of low power supply. Active soil heating with vertical electric probes powered by alternative energy is a viable option for remote sites and presents a low-disturbance option for soil warming experiments. This active heating design provides a valuable tool for examining the impacts of soil warming on ecosystem processes.

  1. Controlled soil warming powered by alternative energy for remote field sites.

    Directory of Open Access Journals (Sweden)

    Jill F Johnstone

    Full Text Available Experiments using controlled manipulation of climate variables in the field are critical for developing and testing mechanistic models of ecosystem responses to climate change. Despite rapid changes in climate observed in many high latitude and high altitude environments, controlled manipulations in these remote regions have largely been limited to passive experimental methods with variable effects on environmental factors. In this study, we tested a method of controlled soil warming suitable for remote field locations that can be powered using alternative energy sources. The design was tested in high latitude, alpine tundra of southern Yukon Territory, Canada, in 2010 and 2011. Electrical warming probes were inserted vertically in the near-surface soil and powered with photovoltaics attached to a monitoring and control system. The warming manipulation achieved a stable target warming of 1.3 to 2 °C in 1 m(2 plots while minimizing disturbance to soil and vegetation. Active control of power output in the warming plots allowed the treatment to closely match spatial and temporal variations in soil temperature while optimizing system performance during periods of low power supply. Active soil heating with vertical electric probes powered by alternative energy is a viable option for remote sites and presents a low-disturbance option for soil warming experiments. This active heating design provides a valuable tool for examining the impacts of soil warming on ecosystem processes.

  2. Monitored Geologic Repository Concept of Operations

    International Nuclear Information System (INIS)

    Curry, P.M.

    1999-01-01

    This updated document provides the top level guidance for development of the individual systems for the MGR which will be further developed in the System Description Documents. This document will serve as guidance for the development of functional interface and operational requirements. However, the data and engineering values presented in Monitored Geologic Repository Concept of Operations are provided as estimates or summaries of the current design. The original analyses or supporting documents must be utilized if the data or engineering values are used for design inputs. The concepts presented will be utilized as inputs for the development of operational concepts for the individual systems. It is recognized that the references listed may contain existing data or data which are to be verified. However, the data and engineering values presented will not impact the concepts presented in this technical document. As such, the data and engineering values are not being tracked as To Be Verified data. This revision was created to incorporate changes resulting from Enhanced Design Alternative II and Revision 3, DCN 01, of the Monitored Geologic Repository Requirements (YMP 1999)

  3. Mapping and monitoring nuclear waste repositories with subsurface electrical resistivity arrays

    International Nuclear Information System (INIS)

    Asch, T.; Morrison, H.F.

    1987-01-01

    The siting and future integrity of nuclear waste repositories is critically dependent on the local ground water regime. Electrical methods seem particularly promising in mapping and monitoring this regime since the electrical conductivity of rocks depends almost entirely on the fluid saturation, salinity and distribution. The most important recent developments in resistivity include the use of numerical modeling and resistivity mapping using subsurface electrodes. The latter yields far greater accuracy and resolution than can be obtained with surface arrays. To illustrate the power of subsurface-surface arrays the authors studied an idealized two dimensional model of a nuclear repository. Since they are interested in emphasizing the anomaly caused by the repository, or subsequent changes over time in its vicinity, the authors discovered that it is very useful to express the apparent resistivity results as percentage differences from either the background (for surface arrays) or from the apparent resistivities observed at a particular depth of the current source (for subsurface arrays). Percent differencing with respect to data at the repository depth dramatically reduce near-surface and topographic effects that usually confound quantitative interpretation of surface surveys. Thus, dc resistivity appears to have great potential for nuclear waste repository mapping and monitoring

  4. Report on the access to the deposition areas of the repository. Shaft or Ramp?

    International Nuclear Information System (INIS)

    Baeckblom, Goeran; Christiansson, Rolf; Hedin, Allan; Norman, Fredrik; Lagerstedt, Leif

    2003-05-01

    During year 2002, SKB launched the site-specific engineering of the repository at the Oskarshamn and Oesthammar candidate sites. A part of the ongoing engineering work is to evaluate and possibly select type of access from surface to the underground deposition areas located at a depth of some 400 to 700 metres below the surface. The project objectives are to provide a basis for comparison and to compare generic options for access routes to the underground deposition areas, to formulate preliminary Design Justification Statements for the continued site-specific engineering of access routes to the underground repository and also to describe and exemplify methodology for optimisation of the repository engineering. In consideration of the requirements of SKB, several alternative access options are explored. The main alternatives are a ramp with one or two operational areas at the surface, a ramp with parallel excavation of a blind shaft and an alternative with shafts only. A suite of objective functions were employed in the evaluation of the main alternatives relating to long-term safety, occupational safety during construction and operation, environmental impact, sustainability of natural resources, total cost, schedules, flexibility and project risks. All alternatives studied are feasible and safe, but the alternative with a spiral ramp and a blind shaft is deemed to be the most favourable option. The alternative has the highest flexibility without any tangible disadvantages related neither to long-term safety, environmental impact nor to schedules. It is an advantage that ramp traffic is drastically reduced as rock and backfilling material is transported by the skip rather than by vehicles in the ramp, thereby reducing risks of accidents and fires in the ramp. The concurrent ramp and shaft excavation also shorten the construction period with 18 months for the underground excavations. The discounted total cost is however 100 million Swedish Kronor higher for this

  5. Studies on an advanced repository system with enhanced engineered barriers (a framework)

    International Nuclear Information System (INIS)

    Fujiwara, A.; Tashiro, S.; Ikari, S.; Suzuki, A.

    1993-01-01

    In order to propose advanced designs of repositories with enhanced engineered barriers of relatively high radioactive wastes such as burnable poisons, channel boxes, control rods and highly irradiated metals, studies started in 1987 and completed the first phase in 1992. This paper presents the framework and brief results of the first phase. The studies set preliminary design concepts of the repositories with various combinations with engineered barriers and natural barriers for different models and locations such as a silo type in shallow land or a tunnel type in intermediate depth. Through the designs, four component technics were picked up and studied for (1) construction of the components in repository; (2) performance evaluation to realize repository design; (3) improvement of circumstances inside or around repository; and (4) surveillance of repository performance to realize the repository designs. Finally, some repository systems were provided using obtained results, and then the applicability and the economy were evaluated. The studies will continue to the second phase focusing on the long-term performance of the repositories

  6. PASS - Project on Alternative Systems Study. Performance assessment of bentonite clay barrier in three repository concepts: VDH, KBS-3 and VLH

    International Nuclear Information System (INIS)

    Pusch, R.; Boergesson, L.

    1992-12-01

    The three repository concepts VDH, KBS3 and VLH have been investigated with respect to their functions in short- and long-term perspectives. The study shows that while KBS3 does not require development of new techniques for excavation and application of buffers and canisters, such development is needed for VLH and VDH. The various physical processes in the deployment part of VDH are more critical and less understood than those in KBS3 and VLH, but the sealing effect of the plugged 'low-temperature' part is sufficiently good to make the concept qualify as a candidate. VLH has the highest and KBS3 the lowest temperature and the latter has the highest potential for good long-term function. (59 refs.)

  7. Managing and Evaluating Digital Repositories

    Science.gov (United States)

    Zuccala, Alesia; Oppenheim, Charles; Dhiensa, Rajveen

    2008-01-01

    Introduction: We examine the role of the digital repository manager, discuss the future of repository management and evaluation and suggest that library and information science schools develop new repository management curricula. Method: Face-to-face interviews were carried out with managers of five different types of repositories and a Web-based…

  8. The repository ecology an approach to understanding repository and service interactions

    CERN Document Server

    CERN. Geneva; Hagemann, Melissa

    2007-01-01

    An increasing number of university institutions and other organisations are deciding to deploy repositories and a growing number of formal and informal distributed services are supporting or capitalising on the information these repositories provide. Despite reasonably well understood technical architectures, early majority adopters may struggle to articulate their place within the actualities of a wider information environment. The idea of a repository ecology provides developers and administrators with a useful way of articulating and analysing their place in the information environment, and the technical and organisational interactions they have, or are developing, with other parts of such an environment. This presentation will provide an overview of the concept of a repository ecology and examine some examples from the domains of scholarly communications and elearning.

  9. Use of Solr and Xapian in the Invenio document repository software

    CERN Document Server

    Glauner, Patrick; Le Meur, Jean-Yves; Simko, Tibor

    2013-01-01

    Invenio is a free comprehensive web-based document repository and digital library software suite originally developed at CERN. It can serve a variety of use cases from an institutional repository or digital library to a web journal. In order to fully use full-text documents for efficient search and ranking, Solr was integrated into Invenio through a generic bridge. Solr indexes extracted full-texts and most relevant metadata. Consequently, Invenio takes advantage of Solr’s efficient search and word similarity ranking capabilities. In this paper, we first give an overview of Invenio, its capabilities and features. We then present our open source Solr integration as well as scalability challenges that arose for an Invenio- based multi-million record repository: the CERN Document Server. We also compare our Solr adapter to an alternative Xapian adapter using the same generic bridge. Both integrations are distributed with the Invenio package and ready to be used by the institutions using or adopting Invenio.

  10. Nuclear waste repository siting and locational conflict analysis: A contextual approach

    International Nuclear Information System (INIS)

    Murauskas, G.T.

    1989-01-01

    This study develops and evaluates an alternative framework that is based on contextual variables. The premise is that differences in attitudes and perceptions regarding the local siting of nuclear wastes and differences in attitudes regarding siting decision-making procedures are influenced by local political, economic, and cultural variables. This framework articulates the nature of conflict in terms of the incongruence between the use-value individuals ascribe to their present situation and the anticipated exchange-value individuals associate with the local siting of a nuclear waste repository. In order to evaluate this conceptual framework a survey was conducted of residents in four communities representing distinct societal contexts: Richton, Mississippi; Peterborough, New Hampshire; Richland, Washington; and Antigo/Waupaca, Wisconsin. Data analyses indicate substantial differences in economic expectations associated with the local siting of a high-level nuclear waste repository and in perception regarding the impacts such a repository might have on the environment, local agriculture, personal health and safety, and the quality of life

  11. Methodology Used for Total System Performance Assessment of the Potential Nuclear Waste Repository at Yucca Mountain (USA)

    International Nuclear Information System (INIS)

    E. Devibec; S.D. Sevougian; P.D. Mattie; J.A. McNeish; S. Mishra

    2001-01-01

    The U.S. Department of Energy and its contractors are currently evaluating a site in Nevada (Yucca Mountain) for disposal of high-level radioactive waste from U.S. commercial nuclear plants and U.S. government-owned facilities. The suitability of the potential geologic repository is assessed, based on its performance in isolating the nuclear waste from the environment. Experimental data and models representing the natural and engineered barriers are combined into a Total System Performance Assessment (TSPA) model [1]. Process models included in the TSPA model are unsaturated zone flow and transport, thermal hydrology, in-drift geochemistry, waste package degradation, waste form degradation, engineered barrier system transport, saturated zone flow and transport, and biosphere transport. Because of the uncertainty in the current data and in the future evolution of the total system, simulations follow a probabilistic approach. Multiple realization simulations using Monte Carlo analysis are conducted over time periods of up to one million years, which estimates a range of possible behaviors of the repository. The environmental impact is measured primarily by the annual dose received by an average member of a critical population group residing 20 km down-gradient of the potential repository. In addition to the nominal scenario, other exposure scenarios include the possibility of disruptive events such as volcanic eruption or intrusion, or accidental human intrusion. Sensitivity to key uncertain processes is analyzed. The influence of stochastic variables on the TSPA model output is assessed by ''uncertainty importance analysis'', e.g., regression analysis and classification tree analysis. Further investigation of the impact of parameters and assumptions is conducted through ''one-off analysis'', which consists in fixing a parameter at a particular value, using an alternative conceptual model, or in making a different assumption. Finally, robustness analysis evaluates

  12. USGS studies of physical--chemical relationships in salt repositories

    International Nuclear Information System (INIS)

    Stewart, D.B.

    1977-01-01

    The amount and physical properties of brine that can occur in salt repositories at elevated temperatures and pressures adjacent to waste-bearing cannisters will have considerable impact on the mechanical strength and stability of the repository. Brine will form readily from H 2 O absorbed on surfaces, diffusion along grain boundaries, movement of fluid inclusions, dehydration of hydrous minerals such as gypsum, polyhalite or clays, or even from leakage through failed shaft openings. A T-P diagram for NaCl--H 2 O shows the limits for coexisting solid-liquid-gas assemblages in salt repositories. Isobaric T-X diagrams are included to show compositional details at pressures below the critical point and above it. Properties of the fluid phases such as volume, density, heat capacity, enthalpy, viscosity, surface tension, osmotic coefficients, etc. can be well described (>0.01% to 2 O. Because aggregates of solids are mechanically weakened by interstitial liquid, determination of mechanical properties of brine-bearing aggregates is needed. A maximum of one third by weight of brine (not H 2 O), and probably much less, will destroy rock strength

  13. Analysis of spent fuel performance in a geologic repository

    International Nuclear Information System (INIS)

    Apted, M.J.; Liebetrau, A.M.; Engel, D.W.; Alexander, D.H.

    1986-04-01

    The Analytical REpository Source-Term (AREST) code developed for the US Department of Energy is being used to assess the time-dependent release rate of radionuclides from spent nuclear fuel disposed in geologic repositories. The Waste Package Release (WPR) submodule of AREST calculates the release from individual waste packages containing spent fuel based on site-specific design, solubility, corrosion, sorption, and mass transfer data. Under the open system conditions of a repository, there are two limiting release mechanisms: surface reaction control and transport control. In addition, a separate release case is defined for soluble radionuclides that are inventory limited. Mass transfer equations for each of these processes are incorporated into AREST. Four separate sources are identified in the AREST code based on inventory and release mechanism: UO 2 matrix (transport limited), gap (inventory limited), grain boundary (inventory limited, combined with gap), and cladding (transport limited). The calculated release of nuclides contained in the matrix (> 90% of the entire inventory) is controlled by UO 2 solubility or the solubility of a nuclide-bearing phase, whichever is lower

  14. Shear-induced Fracture Slip and Permeability Change. Implications for Long-term Performance of a Deep Geological Repository

    International Nuclear Information System (INIS)

    Min, Ki-Bok; Stephansson, Ove

    2009-03-01

    Opening of fractures induced by shear dilation or normal deformation can be a significant source of fracture permeability change in jointed rock, which is important for the performance assessment of geological repositories for spent nuclear fuel. As the repository generates heat and later cools the fluid-carrying ability of the rocks becomes a dynamic variable during the lifespan of the repository. Heating causes expansion of the rock close to the repository and, at the same time, contraction close to the surface. During the cooling phase of the repository, the opposite takes place. Heating and cooling together with the virgin stress can induce shear dilation of fractures and deformation zones and change the flow field around the repository. The objectives of this project are to examine the contribution of thermal stress to the shear slip of fracture in mid- and far-field around a KBS-3 type of repository and to investigate the effect of evolution of stress on the rock mass permeability. The first part of the study is about the evolution of thermal stresses in the rock during the lifetime of the repository. Critical sections of heat generated stresses around the repository are selected and classified. Fracture data from Forsmark is used to establish fracture network models (DFN) and the models are subjected to the sum of virgin stress and thermal stresses and the shear slip and related permeability change are studied. In the first part of this study, zones of fracture shear slip were examined by conducting a three-dimensional, thermo-mechanical analysis of a spent fuel repository model. Stress evolutions of importance for fracture shear slip are: (1) comparatively high horizontal compressive thermal stress at the repository level, (2) generation of vertical tensile thermal stress right above the repository, (3) horizontal tensile stress near the surface, which can induce tensile failure, and generation of shear stresses at the corners of the repository. In the

  15. Shear-induced Fracture Slip and Permeability Change. Implications for Long-term Performance of a Deep Geological Repository

    Energy Technology Data Exchange (ETDEWEB)

    Min, Ki-Bok (School of Civil, Environmental and Mining Engineering, Univ. of Adelaide, Adelaide (Australia)); Stephansson, Ove (Steph Rock Consulting AB, Berlin (Germany))

    2009-03-15

    Opening of fractures induced by shear dilation or normal deformation can be a significant source of fracture permeability change in jointed rock, which is important for the performance assessment of geological repositories for spent nuclear fuel. As the repository generates heat and later cools the fluid-carrying ability of the rocks becomes a dynamic variable during the lifespan of the repository. Heating causes expansion of the rock close to the repository and, at the same time, contraction close to the surface. During the cooling phase of the repository, the opposite takes place. Heating and cooling together with the virgin stress can induce shear dilation of fractures and deformation zones and change the flow field around the repository. The objectives of this project are to examine the contribution of thermal stress to the shear slip of fracture in mid- and far-field around a KBS-3 type of repository and to investigate the effect of evolution of stress on the rock mass permeability. The first part of the study is about the evolution of thermal stresses in the rock during the lifetime of the repository. Critical sections of heat generated stresses around the repository are selected and classified. Fracture data from Forsmark is used to establish fracture network models (DFN) and the models are subjected to the sum of virgin stress and thermal stresses and the shear slip and related permeability change are studied. In the first part of this study, zones of fracture shear slip were examined by conducting a three-dimensional, thermo-mechanical analysis of a spent fuel repository model. Stress evolutions of importance for fracture shear slip are: (1) comparatively high horizontal compressive thermal stress at the repository level, (2) generation of vertical tensile thermal stress right above the repository, (3) horizontal tensile stress near the surface, which can induce tensile failure, and generation of shear stresses at the corners of the repository. In the

  16. Underground excavation methods for a high-level waste repository

    International Nuclear Information System (INIS)

    Peshel, J.; Gupta, D.; Nataraja, M.

    1990-01-01

    This paper reports on rock excavation methods for a High-Level Waste repository that should be selected to limit the potential for creating preferential pathways for groundwater to travel to the waste packages or for radionuclides to migrate to the accessible environment. The use of water and other foreign substances should be controlled so that the repository performance is not compromised. The excavated openings should remain stable so that operations can be carried out safely and the retrievability option maintained. As per the current conceptual designs presented by the Department of Energy, the exploratory shaft facility becomes a part of the repository if the Yucca Mountain site is found suitable for repository development. Therefore, the methods of constructing the underground openings should be compatible with the performance requirements for the repository. Also, the degree of damage to the rock surrounding the openings and the extent of the damage zone should not preclude adequate site characterization. The ESf construction and operation should be compatible with the site data gathering activities, such as geological, thermomechanical, hydrological and geochemical testing

  17. The repository ecology: an approach to understanding repository and service interactions

    CERN Multimedia

    CERN. Geneva

    2007-01-01

    An increasing number of university institutions and other organisations are deciding to deploy repositories and a growing number of formal and informal distributed services are supporting or capitalising on the information these repositories provide. Despite reasonably well understood technical architectures, early majority adopters may struggle to articulate their place within the actualities of a wider information environment. The idea of a repository ecology provides developers and administrators with a useful way of articulating and analysing their place in the information environment, and the technical and organisational interactions they have, or are developing, with other parts of such an environment. This presentation will provide an overview of the concept of a repository ecology and examine some examples from the domains of scholarly communications and elearning. View John Robertson's biography

  18. Nevada potential repository preliminary transportation strategy Study 2. Volume 1

    International Nuclear Information System (INIS)

    1996-02-01

    The objectives of this study were to build on the findings of the Nevada Potential Repository Preliminary Transportation Strategy Study 1 (CRWMS M ampersand O 1995b), and to provide additional information for input to the repository environmental impact statement (EIS) process. In addition, this study supported the future selection of a preferred rail corridor and/or heavy haul route based on defensible data, methods, and analyses. Study research did not consider proposed legislation. Planning was conducted according to the Civilian Radioactive Waste Management Program Plan (DOE 1994a). The specific objectives of Study 2 were to: eliminate or reduce data gaps, inconsistencies, and uncertainties, and strengthen the analysis performed in Study 1; develop a preliminary list of rail route evaluation criteria that could be used to solicit input from stakeholders during scoping meetings. The evaluation criteria will be revised based on comments received during scoping; restrict and refine the width of the four rail corridors identified in Study 1 to five miles or less, based on land use constraints and engineering criteria identified and established in Study 2; evaluate national-level effects of routing spent nuclear fuel and high-level waste to the four identified branch lines, including the effects of routing through or avoiding Las Vegas; continue to gather published land use information and environmental data to support the repository EIS; continue to evaluate heavy haul truck transport over three existing routes as an alternative to rail and provide sufficient information to support the repository EIS process; and evaluate secondary uses for rail (passenger use, repository construction, shared use)

  19. Second generation waste package design and storage concept for the Yucca Mountain Repository

    International Nuclear Information System (INIS)

    Armijo, Joseph Sam; Kar, Piyush; Misra, Manoranjan

    2006-01-01

    The reference waste package design and operating mode to be used in the Yucca Mountain Repository is reviewed. An alternate (second generation) operating concept and waste package design is proposed to reduce the risk of localized corrosion of waste packages and to reduce repository costs. The second generation waste package design and storage concept is proposed for implementation after the initial licensing and operation of the reference repository design. Implementation of the second generation concept at Yucca Mountain would follow regulatory processes analogous to those used successfully to extend the design life and uprate the power of commercial light water nuclear reactors in the United States. The second generation concept utilizes the benefits of hot dry storage to minimize the potential for localized corrosion of the waste package by liquid electrolytes. The second generation concept permits major reductions in repository costs by increasing the number of fuel assemblies stored in each waste package, by eliminating the need for titanium drip shields and by fabricating the outer container from corrosion resistant low alloy carbon steel

  20. Evaluation of the effectiveness and feasibility of the Waste Isolation Pilot Plant engineered alternatives: Final report of the Engineered Alternatives Task Force

    International Nuclear Information System (INIS)

    1991-07-01

    The Engineered Alternatives Task Force (EATF) was established by the United States Department of Energy (DOE) WIPP Project Office (WPO) in September 1989 (Hunt, A., 1990), to evaluate the relative effectiveness and feasibility of implementation of selected design enhancements (referred to as ''engineered alternatives'') for the Waste Isolation Pilot Plant (WIPP). These enhancements consist of modifications of existing waste forms and/or the WIPP facility, and other design variations such as passive marker systems. The purpose of this report is to summarize the methodologies and results of evaluation of the effectiveness of selected engineered alternatives relative to the existing repository design, and to discuss the feasibility of implementing these alternatives with respect to availability of technology, cost, schedule, and regulatory concerns. The EATF has concluded that a number of engineered alternatives could be implemented to improve repository performance if WIPP performance assessment determines that either gas generation or human intrusion presents a problem in demonstrating compliance. Within waste treatment, Level 3 treatments are the most effective in addressing multiple performance parameters, but tend to be the most expensive, the most difficult and time-consuming to implement, and have the greatest regulatory requirements. Level 2 treatments are less expensive, faster, require less extensive permitting, and utilize off- the-shelf technology, but are less effective in addressing multiple performance parameters. Depending upon the performance parameter, Level 1 alternatives such as alternative backfills, alternative waste containers, or modified repository design should be thoroughly evaluated and eliminated before any decision is made to treat the waste. The present uncertainty in the degree to which the baseline WIPP design complies with 40 CFR Part 191 and 40 CFR Part 268 precludes specific recommendations at this time. 130 refs., 21 figs., 37 tabs

  1. Site investigation requirements for a deep repository

    International Nuclear Information System (INIS)

    Farmer, I.W.

    1992-03-01

    Techniques currently available for measuring geotechnical parameters needed in the design, construction and assessment of a deep underground repository have been critically examined. These techniques have been considered under four main areas: definition of the rock discontinuity structure, definition of the in-situ stress distribution in the rock mass, estimation of the geomechanical characteristics of the rock mass, and estimation of flow and transport characteristics of the rock mass. The review concludes that generally rocks and rock masses are not well characterised by tests from cores or from boreholes and gives reason to support this view. The only parameters which can be measured accurately are laboratory index properties which are useful only in a comparative assessment of different rock types. Finally the review concludes that the only way to obtain useful data on rock behaviour is through large pilot scale tests with appropriate and controlled boundary conditions conducted preferably in the potential host strata. (author)

  2. Databases, institutional repositories and an organisational work flow

    CSIR Research Space (South Africa)

    Van der Merwe, Adèle

    2008-06-01

    Full Text Available . In addition, existing open source repository software lacks high level internal quality controls. In an attempt to address compliance, selection and quality control issues, a workflow system was developed for the TOdB system that also impacts...

  3. Alternative methods in criticality

    International Nuclear Information System (INIS)

    Pedicini, J.M.

    1982-01-01

    In this thesis two new methods of calculating the criticality of a nuclear system are introduced and verified. Most methods of determining the criticality of a nuclear system depend implicitly upon knowledge of the angular flux, net currents, or moments of the angular flux, on the system surface in order to know the leakage. For small systems, leakage is the predominant element in criticality calculations. Unfortunately, in these methods the least accurate fluxes, currents, or moments are those occurring near system surfaces or interfaces. This is due to a mathematical inability to satisfy rigorously with a finite order angular polynomial expansion or angular difference technique the physical boundary conditions which occur on these surfaces. Consequently, one must accept large computational effort or less precise criticality calculations. The methods introduced in this thesis, including a direct leakage operator and an indirect multiple scattering leakage operator, obviate the need to know angular fluxes accurately at system boundaries. Instead, the system wide scalar flux, an integral quantity which is substantially easier to obtain with good precision is sufficient to obtain production, absorption, scattering, and leakage rates

  4. Alternative methods in criticality

    International Nuclear Information System (INIS)

    Pedicini, J.M.

    1982-01-01

    Two new methods of calculating the criticality of a nuclear system are introduced and verified. Most methods of determining the criticality of a nuclear system depend implicitly upon knowledge of the angular flux, net currents, or moments of the angular flux, on the system surface in order to know the leakage. For small systems, leakage is the predominant element in criticality calculations. Unfortunately, in these methods the least accurate fluxes, currents, or moments are those occuring near system surfaces or interfaces. This is due to a mathematical inability to satisfy rigorously with a finite order angular polynomial expansion or angular difference technique the physical boundary conditions which occur on these surfaces. Consequently, one must accept large computational effort or less precise criticality calculations. The methods introduced in this thesis, including a direct leakage operator and an indirect multiple scattering leakage operator, obviate the need to know angular fluxes accurately at system boundaries. Instead, the system wide scalar flux, an integral quantity which is substantially easier to obtain with good precision, is sufficient to obtain production, absorption, scattering, and leakage rates

  5. Evaluation of radionuclide releases from underground waste repositories using the method of status vectors

    International Nuclear Information System (INIS)

    Zappe, D.

    1983-01-01

    For safety analyses of underground repositories for radioactive wastes various possible release scenarios have to be defind and anticipated consequences to be calculated and compared. Normally only the main exposure pathways (i.e. the critical pathways) of the radionuclides disposed of in the repository are calculated using deterministic methods and varying the parameters. It is proposed to evaluate all the individual pathways including those differing considerably from the critical pathway by forming weighted averages of their consequences. This offers the possibility of including, without any restriction, in the evaluation of the repository the various possible events and processes that influence the function of barriers for the retention of radionuclides. Various states (scenarios) of a repository in a salt formation, which might occur in the course of time have been used as an example. The consequences related to these states and the probabilities of their occurrence or the scenario weights form the components of 'status vectors'. For low- and intermediate-level wastes the overall consequences obtained from these calculations are negligibly small, for high-level wastes they are about 3 x 10 - 5 Sv a - 1 /GW a. These values are reached if at least a part of the barriers is effective. Variations of the weighting factors for the states and their influence on the overall consequences are given. (author)

  6. Investigation on design of repository for radioactive waste

    International Nuclear Information System (INIS)

    Zhang Boming; Zhang Ruixue; Wang Fengying

    2010-01-01

    The scheme design of the repository for radioactive waste is introduced according to the traits of radioactive waste in Jiangsu province, such as the style of the repository, lifting facilities, the step for preventing or controlling flood, the aseismatic measure, the pollution prevention and so on. This ensured the radioactive waste and the waste radioactive sources to be stored in security, the area environment not to be polluted. It can improve the use of nuclear technology in Jiangsu province. (authors)

  7. Melt-Dilute Spent Nuclear Fuel Form Criticality Summary Report; FINAL

    International Nuclear Information System (INIS)

    Vinson, D.W.

    2002-01-01

    Criticality analysis of the proposed Melt-Dilute (MD) form of aluminum-based spent nuclear fuel (SNF), under geologic repository conditions, was performed following the methodology, documented in the Disposal Criticality Analysis Methodology Topical Report. This methodology evaluates the potential for nuclear criticality as determined by the composition of the waste and its geometry, namely waste form configuration, including presence of moderator, reflecting structural material, and neutron absorbers. The initial emplaced configuration of the SNF form is a dry package placed in a mined repository passageway. Criticality calculations show that even with waste package failure, followed by degradation of material within the waste package and potential loss of neutron absorber materials, sub-critical conditions can be maintained

  8. The relevance of axial burn-up profiles for the criticality safety analysis of spent nuclear fuel in a final repository

    International Nuclear Information System (INIS)

    Kilger, R.; Gmal, B.; Moser, E.F.

    2008-01-01

    Due to inhomogeneous neutron flux and moderator density distributions in the reactor core, the burn-up of a nuclear fuel assembly is not homogeneous but shows an axial distribution, typically with lower partial burn-up and thus higher remaining reactivity at the fuel ends in particular at the assembly top end. Beyond a burn-up of about 15 to 20 GWd/tHM, the multiplication factor K of the whole assembly is dominated by this lower-burnt end regions, and is usually higher than for assuming a homogeneous uniform distribution of the averaged burn-up. This behaviour commonly referred to as positive ''end effect'' is well known in burn-up credit considerations for transportation and storage casks and is being investigated also in the context of criticality analyses for final disposition of spent nuclear fuel. Sign and value of the end effect depend on several parameters. Based on a generic model one may not conclude that criticality in a final repository is a likely or expected event, but nevertheless it draws the attention to the fact that criticality is not excluded per se but has to be considered in the analysis and probably has to be encountered by certain appropriate measures, maybe e.g. by limitation of the amount of fissile material inside one single cask, or a rigorous prove for prevention of water ingress. The authors also conclude that the higher partial reactivity of the fuel ends has to be accounted for carefully in more realistic analyses of post-closure scenarios with respect to criticality safety.

  9. Repository operational criteria analysis

    International Nuclear Information System (INIS)

    Hageman, J.P.; Chowdhury, A.H.

    1992-08-01

    The objective of the ''Repository Operational Criteria (ROC) Feasibility Studies'' (or ROC task) was to conduct comprehensive and integrated analyses of repository design, construction, and operations criteria in 10 CFR Part 60 regulations, considering the interfaces and impacts of any potential changes to those regulations. The study addresses regulatory criteria related to the preclosure aspects of the geologic repository. The study task developed regulatory concepts or potential repository operational criteria (PROC) based on analysis of a repository's safety functions and other regulations for similar facilities. These regulatory concepts or PROC were used as a basis to assess the sufficiency and adequacy of the current criteria in 10 CFR Part 60. Where the regulatory concepts were same as current operational criteria, these criteria were referenced. The operations criteria referenced or the PROC developed are given in this report. Detailed analyses used to develop the regulatory concepts and any necessary PROC for those regulations that may require a minor change are also presented. The results of the ROC task showed a need for further analysis and possible major rule change related to the design bases of a geologic repository operations area, siting, and radiological emergency planning

  10. Consortial routes to effective repositories

    OpenAIRE

    Moyle, M.; Proudfoot, R.

    2009-01-01

    A consortial approach to the establishment of repository services can help a group of Higher Education Institutions (HEIs) to share costs, share technology and share expertise. Consortial repository work can tap into existing structures, or it can involve new groupings of institutions with a common interest in exploring repository development. This Briefing Paper outlines some of the potential benefits of collaborative repository activity, and highlights some of the technical and organisation...

  11. Safety assessment of geologic repositories for nuclear waste

    International Nuclear Information System (INIS)

    Bartlett, J.W.; Burkholder, H.C.; Winegardner, W.K.

    1977-01-01

    Consideration of geologic isolation for final disposition of radioactive wastes has led to the need for evaluation of the safety of the concept. Such evaluations require consideration of factors not encountered in conventional risk analysis: consequences at times and places far removed from the repository site; indirect, complex, and alternative pathways between the waste and the point of potential consequences; a highly limited data base; and limited opportunity for experimental verification of results. R and D programs to provide technical safety evaluations are under way. Three methods are being considered for the probabilistic aspects of the evaluations: fault tree analysis, repository simulation analysis, and system stability analysis. Nuclide transport models, currently in a relatively advanced state of development, are used to evaluate consequences of postulated loss of geologic isolation. This paper outlines the safety assessment methods, unique features of the assessment problem that affect selection of methods and reliability of results, and available results. It also discusses potential directions for future work

  12. Safety assessment for a KBS-3H spent nuclear fuel repository at Olkiluoto. Summary report

    International Nuclear Information System (INIS)

    Smith, Paul; Neall, Fiona; Snellman, Margit; Pastina, Barbara; Nordman, Henrik; Johnson, Lawrence; Hjerpe, Thomas

    2008-03-01

    canister failure may be affected by perturbations due, for example, to the presence of steel components external to the canister in the present KBS-3H reference design. These will corrode over time and interact with the bentonite buffer, affecting its transport properties. In spite of such perturbations, calculated releases are limited and comply with Finnish regulatory criteria in the cases considered. The present safety assessment has some important limitations. In particular, the analysis of a limited range of assessment cases with highly simplified models, especially of the geosphere, is not considered sufficient to test whether the current KBS-3H design at the Olkiluoto site satisfies all relevant regulatory guidelines. Further limitations are that the feasibility of implementing the current reference design has been assumed, even though several design issues remain to be addressed. Furthermore, only single canister failure cases have been considered. Nevertheless, it can be concluded, based on the present safety assessment, that the KBS-3H design alternative offers potential for the full demonstration of safety for a repository at Olkiluoto site and for the demonstration that it fulfills the same long-term safety requirements as KBS-3V. Remaining critical scientific and design issues are highlighted in this report. These include the further development of the DAWE (Drainage, Artificial Watering and air Evacuation) design alternative to avoid uncertainties associated with the buffer saturation process, as well as studies of iron/ bentonite interaction and the possible use of materials such as titanium in place of steel for some system components

  13. Safety assessment for a KBS-3H spent nuclear fuel repository at Olkiluoto. Summary report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Paul; Neall, Fiona; Snellman, Margit; Pastina, Barbara; Nordman, Henrik; Johnson, Lawrence; Hjerpe, Thomas

    2008-03-15

    event of canister failure may be affected by perturbations due, for example, to the presence of steel components external to the canister in the present KBS-3H reference design. These will corrode over time and interact with the bentonite buffer, affecting its transport properties. In spite of such perturbations, calculated releases are limited and comply with Finnish regulatory criteria in the cases considered. The present safety assessment has some important limitations. In particular, the analysis of a limited range of assessment cases with highly simplified models, especially of the geosphere, is not considered sufficient to test whether the current KBS-3H design at the Olkiluoto site satisfies all relevant regulatory guidelines. Further limitations are that the feasibility of implementing the current reference design has been assumed, even though several design issues remain to be addressed. Furthermore, only single canister failure cases have been considered. Nevertheless, it can be concluded, based on the present safety assessment, that the KBS-3H design alternative offers potential for the full demonstration of safety for a repository at Olkiluoto site and for the demonstration that it fulfills the same long-term safety requirements as KBS-3V. Remaining critical scientific and design issues are highlighted in this report. These include the further development of the DAWE (Drainage, Artificial Watering and air Evacuation) design alternative to avoid uncertainties associated with the buffer saturation process, as well as studies of iron/ bentonite interaction and the possible use of materials such as titanium in place of steel for some system components

  14. Consideration of nuclear criticality when disposing of transuranic waste at the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    RECHARD,ROBERT P.; SANCHEZ,LAWRENCE C.; STOCKMAN,CHRISTINE T.; TRELLUE,HOLLY R.

    2000-04-01

    Based on general arguments presented in this report, nuclear criticality was eliminated from performance assessment calculations for the Waste Isolation Pilot Plant (WIPP), a repository for waste contaminated with transuranic (TRU) radioisotopes, located in southeastern New Mexico. At the WIPP, the probability of criticality within the repository is low because mechanisms to concentrate the fissile radioisotopes dispersed throughout the waste are absent. In addition, following an inadvertent human intrusion into the repository (an event that must be considered because of safety regulations), the probability of nuclear criticality away from the repository is low because (1) the amount of fissile mass transported over 10,000 yr is predicted to be small, (2) often there are insufficient spaces in the advective pore space (e.g., macroscopic fractures) to provide sufficient thickness for precipitation of fissile material, and (3) there is no credible mechanism to counteract the natural tendency of the material to disperse during transport and instead concentrate fissile material in a small enough volume for it to form a critical concentration. Furthermore, before a criticality would have the potential to affect human health after closure of the repository--assuming that a criticality could occur--it would have to either (1) degrade the ability of the disposal system to contain nuclear waste or (2) produce significantly more radioisotopes than originally present. Neither of these situations can occur at the WIPP; thus, the consequences of a criticality are also low.

  15. Consideration of nuclear criticality when disposing of transuranic waste at the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Rechard, Robert P.; Sanchez, Lawrence C.; Stockman, Christine T.; Trellue, Holly R.

    2000-01-01

    Based on general arguments presented in this report, nuclear criticality was eliminated from performance assessment calculations for the Waste Isolation Pilot Plant (WIPP), a repository for waste contaminated with transuranic (TRU) radioisotopes, located in southeastern New Mexico. At the WIPP, the probability of criticality within the repository is low because mechanisms to concentrate the fissile radioisotopes dispersed throughout the waste are absent. In addition, following an inadvertent human intrusion into the repository (an event that must be considered because of safety regulations), the probability of nuclear criticality away from the repository is low because (1) the amount of fissile mass transported over 10,000 yr is predicted to be small, (2) often there are insufficient spaces in the advective pore space (e.g., macroscopic fractures) to provide sufficient thickness for precipitation of fissile material, and (3) there is no credible mechanism to counteract the natural tendency of the material to disperse during transport and instead concentrate fissile material in a small enough volume for it to form a critical concentration. Furthermore, before a criticality would have the potential to affect human health after closure of the repository--assuming that a criticality could occur--it would have to either (1) degrade the ability of the disposal system to contain nuclear waste or (2) produce significantly more radioisotopes than originally present. Neither of these situations can occur at the WIPP; thus, the consequences of a criticality are also low

  16. Repository performance confirmation

    International Nuclear Information System (INIS)

    Hansen, Francis D.

    2011-01-01

    Repository performance confirmation links the technical bases of repository science and societal acceptance. This paper explores the myriad aspects of what has been labeled performance confirmation in U.S. programs, which involves monitoring as a collection of distinct activities combining technical and social significance in radioactive waste management. This paper is divided into four parts: (1) A distinction is drawn between performance confirmation monitoring and other testing and monitoring objectives; (2) A case study illustrates confirmation activities integrated within a long-term testing and monitoring strategy for Yucca Mountain; (3) A case study reviews compliance monitoring developed and implemented for the Waste Isolation Pilot Plant; and (4) An approach for developing, evaluating and implementing the next generation of performance confirmation monitoring is presented. International interest in repository monitoring is exhibited by the European Commission Seventh Framework Programme 'Monitoring Developments for Safe Repository Operation and Staged Closure' (MoDeRn) Project. The MoDeRn partners are considering the role of monitoring in a phased approach to the geological disposal of radioactive waste. As repository plans advance in different countries, the need to consider monitoring strategies within a controlled framework has become more apparent. The MoDeRn project pulls together technical and societal experts to assimilate a common understanding of a process that could be followed to develop a monitoring program. A fundamental consideration is the differentiation of confirmation monitoring from the many other testing and monitoring activities. Recently, the license application for Yucca Mountain provided a case study including a technical process for meeting regulatory requirements to confirm repository performance as well as considerations related to the preservation of retrievability. The performance confirmation plan developed as part of the

  17. 7 CFR 58.141 - Alternate quality control program.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Alternate quality control program. 58.141 Section 58... Service 1 Quality Specifications for Raw Milk § 58.141 Alternate quality control program. When a plant has in operation an acceptable quality program, at the producer level, which is approved by the...

  18. Safety assessment for a KBS-3H spent nuclear fuel repository at Olkiluoto. Evolution report

    International Nuclear Information System (INIS)

    Smith, P.; Johnson, L.; Snellman, M.; Pastina, B.; Gribi, P.

    2007-12-01

    The KBS-3 method, based on multiple barriers, is the proposed spent fuel disposal method both in Sweden and Finland. KBS-3H and KBS-3V are the two design alternatives of the KBS-3 method. Posiva and SKB have conducted a joint research, demonstration and development (RD and D) programme in 2002-2007 with the overall aim of establishing whether KBS-3H represents a feasible alternative to the reference alternative KBS-3V. The overall objectives of the present phase covering the period 2004-2007, have been to demonstrate that the horizontal deposition alternative is technically feasible and to demonstrate that it fulfils the same long-term safety requirements as KBS-3V. The safety studies conducted as part of this programme include a safety assessment of a preliminary design of a KBS-3H repository for spent nuclear fuel located about 400 m underground at the Olkiluoto site, which is the proposed site for a spent fuel repository in Finland. In the KBS-3H design alternative, each canister, with a surrounding layer of bentonite clay, is pre-packaged in a perforated steel cylinder prior to emplacement in the deposition drift; the entire assembly is called the supercontainer. Several supercontainers are positioned along parallel, 100 - 300 m long deposition drifts, which are sealed following waste emplacement using drift end plugs. Bentonite distance blocks separate the supercontainers, one from another, along the drift. Steel compartment plugs can be used to seal off drift sections with higher inflow, thus isolating the different compartments within the drift. The present report describes the repository evolution in successive time frames, including key uncertainties. The description of evolution starts with the initial conditions at the time of emplacement of the first canisters. The repository evolves through an early, transient phase to a state where evolution is far slower. Particular attention is given to describing the transient phase, since this is where most of the

  19. Safety assessment for a KBS-3H spent nuclear fuel repository at Olkiluoto. Evolution report

    International Nuclear Information System (INIS)

    Smith, Paul; Johnson, Lawrence; Snellman, Margit; Pastina, Barbara; Gribi, Peter

    2008-01-01

    The KBS-3 method, based on multiple barriers, is the proposed spent fuel disposal method both in Sweden and Finland. KBS-3H and KBS-3V are the two design alternatives of the KBS-3 method. Posiva and SKB have conducted a joint research, demonstration and development (RDandD) programme in 2002-2007 with the overall aim of establishing whether KBS-3H represents a feasible alternative to the reference alternative KBS-3V. The overall objectives of the present phase covering the period 2004-2007, have been to demonstrate that the horizontal deposition alternative is technically feasible and to demonstrate that it fulfils the same long-term safety requirements as KBS-3V. The safety studies conducted as part of this programme include a safety assessment of a preliminary design of a KBS-3H repository for spent nuclear fuel located about 400 m underground at the Olkiluoto site, which is the proposed site for a spent fuel repository in Finland. In the KBS-3H design alternative, each canister, with a surrounding layer of bentonite clay, is pre-packaged in a perforated steel cylinder prior to emplacement in the deposition drift; the entire assembly is called the supercontainer. Several supercontainers are positioned along parallel, 100-300 m long deposition drifts, which are sealed following waste emplacement using drift end plugs. Bentonite distance blocks separate the supercontainers, one from another, along the drift. Steel compartment plugs can be used to seal off drift sections with higher inflow, thus isolating the different compartments within the drift. The present report describes the repository evolution in successive time frames, including key uncertainties. The description of evolution starts with the initial conditions at the time of emplacement of the first canisters. The repository evolves through an early, transient phase to a state where evolution is far slower. Particular attention is given to describing the transient phase, since this is where most of the

  20. Safety assessment for a KBS-3H spent nuclear fuel repository at Olkiluoto. Evolution report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Paul; Johnson, Lawrence; Snellman, Margit; Pastina, Barbara; Gribi, Peter

    2008-01-15

    The KBS-3 method, based on multiple barriers, is the proposed spent fuel disposal method both in Sweden and Finland. KBS-3H and KBS-3V are the two design alternatives of the KBS-3 method. Posiva and SKB have conducted a joint research, demonstration and development (RDandD) programme in 2002-2007 with the overall aim of establishing whether KBS-3H represents a feasible alternative to the reference alternative KBS-3V. The overall objectives of the present phase covering the period 2004-2007, have been to demonstrate that the horizontal deposition alternative is technically feasible and to demonstrate that it fulfils the same long-term safety requirements as KBS-3V. The safety studies conducted as part of this programme include a safety assessment of a preliminary design of a KBS-3H repository for spent nuclear fuel located about 400 m underground at the Olkiluoto site, which is the proposed site for a spent fuel repository in Finland. In the KBS-3H design alternative, each canister, with a surrounding layer of bentonite clay, is pre-packaged in a perforated steel cylinder prior to emplacement in the deposition drift; the entire assembly is called the supercontainer. Several supercontainers are positioned along parallel, 100-300 m long deposition drifts, which are sealed following waste emplacement using drift end plugs. Bentonite distance blocks separate the supercontainers, one from another, along the drift. Steel compartment plugs can be used to seal off drift sections with higher inflow, thus isolating the different compartments within the drift. The present report describes the repository evolution in successive time frames, including key uncertainties. The description of evolution starts with the initial conditions at the time of emplacement of the first canisters. The repository evolves through an early, transient phase to a state where evolution is far slower. Particular attention is given to describing the transient phase, since this is where most of the

  1. Final repository for spent nuclear fuel. Underground design Forsmark, Layout D1

    International Nuclear Information System (INIS)

    Brantberger, Martin; Zetterqvist, Anders; Arnbjerg-Nielsen, Torben; Olsson, Tommy; Outters, Nils; Syrjaenen, Pauli

    2006-04-01

    This report comprises the design step D1 related to the underground design for a deep repository located at the Forsmark site. The design is based on the Site Descriptive Model Forsmark v1.2. All studies have been focussed at an area southeast of the Forsmark nuclear plant, which has been considered to be the most promising area for hosting the repository. SKB has developed guidelines for the design of the repository, which further describes the methodology applied for the studies. From these guidelines the following basic objectives for the design step D1 are summarized: to determine whether the final repository can be accommodated within the studied site; to identify site-specific facility critical issues; to test and evaluate the design methodology; to provide feedback to: the design organisation regarding additional studies that needs to be done; the site investigation and modelling organization regarding further investigations required; and the safety assessment team. The possible locations for a tentative deep repository are analysed in Chapter 3 of the report. The most promising area for the repository (denoted 'priority site') has been defined by SKB to be located southeast of the Forsmark nuclear plant and northwest of the gently dipping deformation zone ZFMNE00A2. Regarding the repository depth, present knowledge acquired from the site investigations indicates that it is possible to locate the repository at all stipulated depths according to SKB, that is between 400 m and 700 m depth. The preliminary assessment made in Chapter 3 clearly demonstrates that the repository can be accommodated within the 'priority site'. The potential to accommodate the repository is essentially the same for both 400 m and 500 m depths. The design of the deposition areas is reported in Chapter 4, which includes the design of layout features for all tunnels and deposition holes, orientation of tunnels, calculation of anticipated loss of deposition holes due to the applied

  2. Final repository for spent nuclear fuel. Underground design Forsmark, Layout D1

    Energy Technology Data Exchange (ETDEWEB)

    Brantberger, Martin; Zetterqvist, Anders [Ramboell Sweden AB, Stockholm (Sweden); Arnbjerg-Nielsen, Torben [Ramboell Denmark A/S, Virum (Denmark); Olsson, Tommy [IandT Olsson AB, Uppsala (Sweden); Outters, Nils [Golder Associates AB, Uppsala (Sweden); Syrjaenen, Pauli [Gridpoint Oy, Helsinki (Sweden)

    2006-04-15

    This report comprises the design step D1 related to the underground design for a deep repository located at the Forsmark site. The design is based on the Site Descriptive Model Forsmark v1.2. All studies have been focussed at an area southeast of the Forsmark nuclear plant, which has been considered to be the most promising area for hosting the repository. SKB has developed guidelines for the design of the repository, which further describes the methodology applied for the studies. From these guidelines the following basic objectives for the design step D1 are summarized: to determine whether the final repository can be accommodated within the studied site; to identify site-specific facility critical issues; to test and evaluate the design methodology; to provide feedback to: the design organisation regarding additional studies that needs to be done; the site investigation and modelling organization regarding further investigations required; and the safety assessment team. The possible locations for a tentative deep repository are analysed in Chapter 3 of the report. The most promising area for the repository (denoted 'priority site') has been defined by SKB to be located southeast of the Forsmark nuclear plant and northwest of the gently dipping deformation zone ZFMNE00A2. Regarding the repository depth, present knowledge acquired from the site investigations indicates that it is possible to locate the repository at all stipulated depths according to SKB, that is between 400 m and 700 m depth. The preliminary assessment made in Chapter 3 clearly demonstrates that the repository can be accommodated within the 'priority site'. The potential to accommodate the repository is essentially the same for both 400 m and 500 m depths. The design of the deposition areas is reported in Chapter 4, which includes the design of layout features for all tunnels and deposition holes, orientation of tunnels, calculation of anticipated loss of deposition holes due

  3. Demystifying the institutional repository for success

    CERN Document Server

    Buehler, Marianne

    2013-01-01

    Institutional repositories remain key to data storage on campus, fulfilling the academic needs of various stakeholders. Demystifying the Institutional Repository for Success is a practical guide to creating and sustaining an institutional repository through marketing, partnering, and understanding the academic needs of all stakeholders on campus. This title is divided into seven chapters, covering: traditional scholarly communication and open access publishing; the academic shift towards open access; what the successful institutional repository looks like; institutional repository collaboratio

  4. Effect of repository underground ventilation on emplacement drift temperature control

    International Nuclear Information System (INIS)

    Yang, H.; Sun, Y.; McKenzie, D.G.; Bhattacharyya, K.K.

    1996-01-01

    The repository advanced conceptual design (ACD) is being conducted by the Civilian Radioactive Waste Management System, Management ampersand Operating Contractor. Underground ventilation analyses during ACD have resulted in preliminary ventilation concepts and design methodologies. This paper discusses one of the recent evaluations -- effects of ventilation on emplacement drift temperature management

  5. Citing and Reading Behaviours in High-Energy Physics : How a Community Stopped Worrying about Journals and Learned to Love Repositories

    CERN Document Server

    Gentil-Beccot, A; Brooks, T

    2010-01-01

    Contemporary scholarly discourse follows many alternative routes in addition to the three-century old tradition of publication in peer-reviewed journals. The field of High- Energy Physics (HEP) has explored alternative communication strategies for decades, initially via the mass mailing of paper copies of preliminary manuscripts, then via the inception of the first online repositories and digital libraries. This field is uniquely placed to answer recurrent questions raised by the current trends in scholarly communication: is there an advantage for scientists to make their work available through repositories, often in preliminary form? Is there an advantage to publishing in Open Access journals? Do scientists still read journals or do they use digital repositories? The analysis of citation data demonstrates that free and immediate online dissemination of preprints creates an immense citation advantage in HEP, whereas publication in Open Access journals presents no discernible advantage. In addition, the analys...

  6. The European Repository Landscape 2008 Inventory of Digital Repositories for Research Output

    CERN Document Server

    Van der Graaf, Maurits

    2009-01-01

    It is widely acknowledged that a common knowledge base for European research is necessary. Research repositories are an important innovation to the scientific information infrastructure. In 2006, digital repositories in the 27 countries of the European we

  7. The analysis of repository-heat-driven hydrothermal flow at Yucca Mountain

    International Nuclear Information System (INIS)

    Buscheck, T.A.; Nitao, J.J.

    1993-01-01

    To safely and permanently store high-level nuclear waste, the potential Yucca Mountain repository site must mitigate the release and transport of radionuclides for tens of thousands of years. In the failure scenario of greatest concern, water would contact the waste package (WP), accelerate its failure rate, and eventually transport radionuclides to the water table. In a concept called the ''extended-dry repository,'' decay heat arising from radioactive waste extends the time before liquid water can contact a WP. Recent modeling and theoretical advances in nonisothermal, multiphase fracture-matrix flow have demonstrated (1) the critical importance of capillary pressure disequilibrium between fracture and matrix flow, and (2) that radioactive decay heat plays a dominant role in the ability of the engineered and natural barriers to contain and isolate radionuclides. Our analyses indicate that the thermo-hydrological performance of both the unsaturated zone (UZ) and saturated zone (SZ) will be dominated by repository-heat-driven hydrothermal flow for tens of thousands of years. For thermal loads resulting in extended-dry repository conditions, UZ performance is primarily sensitive to the thermal properties and thermal loading conditions and much less sensitive to the highly spatially and temporally variable ambient hydrologic properties and conditions. The magnitude of repository-heat-driven buoyancy flow in the SZ is far more dependent on the total mass of emplaced spent nuclear fuel (SNF) than on the details of SNF emplacement, such as the Areal Power Density [(APD) expressed in kill/acre] or SNF age

  8. Office of Geologic Repositories quality assurance plan for high-level radioactive waste repositories

    International Nuclear Information System (INIS)

    1986-08-01

    This document sets forth geologic repository program-wide quality assurance program requirements and defines management's quality assurance responsibilities for the Office of Geologic Repositories and its projects. (LM)

  9. Virtual patient repositories--a comparative analysis.

    Science.gov (United States)

    Küfner, Julia; Kononowicz, Andrzej A; Hege, Inga

    2014-01-01

    Virtual Patients (VPs) are an important component of medical education. One way to reduce the costs for creating VPs is sharing through repositories. We conducted a literature review to identify existing repositories and analyzed the 17 included repositories in regards to the search functions and metadata they provide. Most repositories provided some metadata such as title or description, whereas other data, such as educational objectives, were less frequent. Future research could, in cooperation with the repository provider, investigate user expectations and usage patterns.

  10. Technology overview of mined repositories

    International Nuclear Information System (INIS)

    Gimera, R.; Thirumalai, K.

    1982-01-01

    Mined repositories present an environmentally viable option for permanent disposal of nuclear waste. This paper reviews the state-of-the-art mining technologies and identifies technological issues and developments necessary to mine a repository in basalt. The thermal loading, isolation, and retrieval requirements of a repository present unique technological challenges unknown to conventional mining practice. The technology issues and developments required in the areas of excavation, roof and ground support, equipment development, instrumentation development, and sealing are presented. Performance assessment methods must be developed to evaluate the adequacies of technologies developed to design, construct, operate, and decommission a repository. A stepwise test-and-development approach is used in the Basalt Waste Isolation Project to develop cost-effective technologies for a repository

  11. Breast Cancer Tissue Repository

    National Research Council Canada - National Science Library

    Iglehart, J

    1997-01-01

    The Breast Tissue Repository at Duke enters its fourth year of finding. The purpose of the Repository at Duke is to provide substantial quantities of frozen tissue for explorative molecular studies...

  12. Systems impacts of spent fuel disassembly alternatives

    International Nuclear Information System (INIS)

    1984-07-01

    Three studies were completed to evaluate four alternatives to the disposal of intact spent fuel assemblies in a geologic repository. A preferred spent fuel waste form for disposal was recommended on consideration of (1) package design and fuel/package interaction, (2) long-term, in-repository performance of the waste form, and (3) overall process performance and costs for packaging, handling, and emplacement. The four basic alternative waste forms considered were (1) end fitting removal, (2) fission gas venting, (3) disassembly and close packing, and (4) shearing/immobilization. None of the findings ruled out any alternative on the basis of waste package considerations or long-term performance of the waste form. The third alternative offers flexibility in loading that may prove attractive in the various geologic media under consideration, greatly reduces the number of packages, and has the lowest unit cost. These studies were completed in October, 1981. Since then Westinghouse Electric Corporation and the Office of Nuclear Waste Isolation have completed studies in related fields. This report is now being published to provide publicly the background material that is contained within. 47 references, 28 figures, 31 tables

  13. The neurogenetics of alternative splicing.

    Science.gov (United States)

    Vuong, Celine K; Black, Douglas L; Zheng, Sika

    2016-05-01

    Alternative precursor-mRNA splicing is a key mechanism for regulating gene expression in mammals and is controlled by specialized RNA-binding proteins. The misregulation of splicing is implicated in multiple neurological disorders. We describe recent mouse genetic studies of alternative splicing that reveal its critical role in both neuronal development and the function of mature neurons. We discuss the challenges in understanding the extensive genetic programmes controlled by proteins that regulate splicing, both during development and in the adult brain.

  14. Repository Safety Strategy: Strategy for Protecting Public Health and Safety after Closure of a Yucca Mountain Repository, Rev. 1

    Energy Technology Data Exchange (ETDEWEB)

    DOE

    1998-01-01

    The updated Strategy to Protect Public Health and Safety explains the roles that the natural and engineered systems are expected to play in achieving the objectives of a potential repository system at Yucca Mountain. These objectives are to contain the radionuclides within the waste packages for thousands of years, and to ensure that annual doses to a person living near the site will be acceptably low. This strategy maintains the key assumption of the Site Characterization Plan (DOE 1988) strategy that the potential repository level (horizon) will remain unsaturated. Thus, the strategy continues to rely on the natural attributes of the unsaturated zone for primary protection by providing a setting where waste packages assisted by other engineered barriers are expected to contain wastes for thousands of years. As in the Site Characterization Plan (DOE 1988) strategy, the natural system from the walls of the underground openings (drifts) to the human environment is expected to provide additional defense by reducing the concentrations of any radionuclides released from the waste packages. The updated Strategy to Protect Public Health and Safety is the framework for the integration of site information, repository design and assessment of postclosure performance to develop a safety case for the viability assessment and a subsequent license application. Current site information and a reference design are used to develop a quantitative assessment of performance to be compared with a performance measure. Four key attributes of an unsaturated repository system that are critical to meeting the objectives: (1) Limited water contacting the waste packages; (2) Long waste package lifetime; (3) Slow rate of release of radionuclides from the waste form; and (4) Concentration reduction during transport through engineered and natural barriers.

  15. Deep repository for long-lived low- and intermediate-level waste in Sweden (SFL 3-5): An international peer review of SKB 's preliminary safety assessment

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, N. [QuantiSci Ltd, Melton Mowbray (United Kingdom); Apted, M. [Monitor Scientific, Denver, CO (United States); Glasser, F. [Univ. of Aberdeen (United Kingdom). Dept. of Chemistry; Kessler, J. [EPRI, Inc., Palo Alto, CA (United States); Voss, C. [US Geological Survey, Reston, VA (United States)

    2000-10-01

    presented, no thorough systems analysis and sensitivity study, it is difficult to dispel this impression, which may be much too pessimistic. The review group believes that this may need to be soon, if the SFL 3-5 repository is indeed to be on the critical path for siting the spent fuel repository. The following points summarise some of the main findings of the review: The systematic basis of the study is rather weak. To address safety relevant issues comprehensively, a future study needs to look at a full 'systems approach' to evaluating relevant FEPs and constructing appropriate scenarios. In particular, the potential impacts of climate change, including scenarios involving permafrost and glaciation, have not been considered seriously. Alternative conceptual models of the central processes need to be evaluated. The degree of conservatism of present assumptions needs to be identified on a factor-by-factor basis. A proper sensitivity study is needed. The radionuclide inventory developed for this study is an excellent first step and has been presented extremely well. The physical and chemical compositions and properties of waste streams are also important. The review team note the necessary use of correlation factors to estimate radionuclide inventories, and several suggestions have been made for clarifying or reducing the uncertainties surrounding their application. SKB should consider how best to present the design basis and safety concept for SFL 3-5. At present, the report gives the impression of the design having evolved on a rather ad hoc basis, as no comprehensive explanation is provided of why the pre-study design was judged to be less adequate, what the design options are and how decisions have been reached on which route to adopt. A central facet of the safety study is the hydraulic cage concept. The concept needs significantly more work on its sensitivity to various factors, carried out via a proper scenario analysis. The lack of use of available site

  16. Data base for site specific migration analysis of radioactive elements in repositories

    Energy Technology Data Exchange (ETDEWEB)

    Hadermann, J

    1982-01-01

    Migration analysis is of considerable importance in long-term safety aspects of radioactive waste repositories. The present work gives the data base for a selected part of a comprehensive geosphere transport calculation. We restrict ourselves to a critical evaluation of parameters pertinent to the migration analysis of the /sup 245/Cm chain. This includes the important nuclide /sup 237/Np. With these we are able to perform a site specific calculation for repositories planned in deep geologic formations in Switzerland. It is shown that the granitic basement induces strong time delays in nuclide migration. In contrast to that, the overlaying sedimentary layers cause primarily a dilution of the radionuclide concentrations.

  17. On solution to the problem of criticality by alternative Monte Carlo method

    International Nuclear Information System (INIS)

    Kyncl, J.

    2005-03-01

    The problem of criticality for the neutron transport equation is analyzed. The problem is transformed into an equivalent problem in a suitable set of complex functions, and the existence and uniqueness of its solution is demonstrated. The source iteration method is discussed. It is shown that the final result of the iterative process is strongly affected by the insufficient accuracy of the individual iterations. A modified method is suggested to circumvent this problem based on the theory of positive operators; the criticality problem is solved by the Monte Carlo method constructing special random process and variable so that the difference between the result and the true value can be arbitrarily small. The efficiency of this alternative method is analysed

  18. Methods for assessing the socioeconomic impacts of large-scale resource developments: implications for nuclear repository siting

    International Nuclear Information System (INIS)

    Murdock, S.H.; Leistritz, F.L.

    1983-03-01

    An overview of the major methods presently available for assessing the socioeconomic impacts of large-scale resource developments and includes discussion of the implications and applications of such methods for nuclear-waste-repository siting are provided. The report: (1) summarizes conceptual approaches underlying, and methodological alternatives for, the conduct of impact assessments in each substantive area, and then enumerates advantages and disadvantages of each alternative; (2) describes factors related to the impact-assessment process, impact events, and the characteristics of rural areas that affect the magnitude and distribution of impacts and the assessment of impacts in each area; (3) provides a detailed review of those methodologies actually used in impact assessment for each area, describes advantages and problems encountered in the use of each method, and identifies the frequency of use and the general level of acceptance of each technique; and (4) summarizes the implications of each area of projection for the repository-siting process, the applicability of the methods for each area to the special and standard features of repositories, and makes general recommendations concerning specific methods and procedures that should be incorporated in assessments for siting areas

  19. Revision history aware repositories of computational models of biological systems.

    Science.gov (United States)

    Miller, Andrew K; Yu, Tommy; Britten, Randall; Cooling, Mike T; Lawson, James; Cowan, Dougal; Garny, Alan; Halstead, Matt D B; Hunter, Peter J; Nickerson, David P; Nunns, Geo; Wimalaratne, Sarala M; Nielsen, Poul M F

    2011-01-14

    Building repositories of computational models of biological systems ensures that published models are available for both education and further research, and can provide a source of smaller, previously verified models to integrate into a larger model. One problem with earlier repositories has been the limitations in facilities to record the revision history of models. Often, these facilities are limited to a linear series of versions which were deposited in the repository. This is problematic for several reasons. Firstly, there are many instances in the history of biological systems modelling where an 'ancestral' model is modified by different groups to create many different models. With a linear series of versions, if the changes made to one model are merged into another model, the merge appears as a single item in the history. This hides useful revision history information, and also makes further merges much more difficult, as there is no record of which changes have or have not already been merged. In addition, a long series of individual changes made outside of the repository are also all merged into a single revision when they are put back into the repository, making it difficult to separate out individual changes. Furthermore, many earlier repositories only retain the revision history of individual files, rather than of a group of files. This is an important limitation to overcome, because some types of models, such as CellML 1.1 models, can be developed as a collection of modules, each in a separate file. The need for revision history is widely recognised for computer software, and a lot of work has gone into developing version control systems and distributed version control systems (DVCSs) for tracking the revision history. However, to date, there has been no published research on how DVCSs can be applied to repositories of computational models of biological systems. We have extended the Physiome Model Repository software to be fully revision history aware

  20. Revision history aware repositories of computational models of biological systems

    Directory of Open Access Journals (Sweden)

    Nickerson David P

    2011-01-01

    Full Text Available Abstract Background Building repositories of computational models of biological systems ensures that published models are available for both education and further research, and can provide a source of smaller, previously verified models to integrate into a larger model. One problem with earlier repositories has been the limitations in facilities to record the revision history of models. Often, these facilities are limited to a linear series of versions which were deposited in the repository. This is problematic for several reasons. Firstly, there are many instances in the history of biological systems modelling where an 'ancestral' model is modified by different groups to create many different models. With a linear series of versions, if the changes made to one model are merged into another model, the merge appears as a single item in the history. This hides useful revision history information, and also makes further merges much more difficult, as there is no record of which changes have or have not already been merged. In addition, a long series of individual changes made outside of the repository are also all merged into a single revision when they are put back into the repository, making it difficult to separate out individual changes. Furthermore, many earlier repositories only retain the revision history of individual files, rather than of a group of files. This is an important limitation to overcome, because some types of models, such as CellML 1.1 models, can be developed as a collection of modules, each in a separate file. The need for revision history is widely recognised for computer software, and a lot of work has gone into developing version control systems and distributed version control systems (DVCSs for tracking the revision history. However, to date, there has been no published research on how DVCSs can be applied to repositories of computational models of biological systems. Results We have extended the Physiome Model

  1. National Aeronautics and Space Administration Biological Specimen Repository

    Science.gov (United States)

    McMonigal, Kathleen A.; Pietrzyk, Robert a.; Johnson, Mary Anne

    2008-01-01

    The National Aeronautics and Space Administration Biological Specimen Repository (Repository) is a storage bank that is used to maintain biological specimens over extended periods of time and under well-controlled conditions. Samples from the International Space Station (ISS), including blood and urine, will be collected, processed and archived during the preflight, inflight and postflight phases of ISS missions. This investigation has been developed to archive biosamples for use as a resource for future space flight related research. The International Space Station (ISS) provides a platform to investigate the effects of microgravity on human physiology prior to lunar and exploration class missions. The storage of crewmember samples from many different ISS flights in a single repository will be a valuable resource with which researchers can study space flight related changes and investigate physiological markers. The development of the National Aeronautics and Space Administration Biological Specimen Repository will allow for the collection, processing, storage, maintenance, and ethical distribution of biosamples to meet goals of scientific and programmatic relevance to the space program. Archiving of the biosamples will provide future research opportunities including investigating patterns of physiological changes, analysis of components unknown at this time or analyses performed by new methodologies.

  2. The Listening and Spoken Language Data Repository: Design and Project Overview

    Science.gov (United States)

    Bradham, Tamala S.; Fonnesbeck, Christopher; Toll, Alice; Hecht, Barbara F.

    2018-01-01

    Purpose: The purpose of the Listening and Spoken Language Data Repository (LSL-DR) was to address a critical need for a systemwide outcome data-monitoring program for the development of listening and spoken language skills in highly specialized educational programs for children with hearing loss highlighted in Goal 3b of the 2007 Joint Committee…

  3. A performance assessment review tool for the proposed radioactive waste repository at Yucca Mountain, Nevada, USA

    International Nuclear Information System (INIS)

    Mohanty, Sitakanta; Codell, Richard

    2000-01-01

    The U.S. Nuclear Regulatory Commission (NRC), with the assistance of the Center for Nuclear Waste Regulatory Analyses, has developed a Total-system Performance Assessment (TPA) Code to assist in evaluating the performance of the Yucca Mountain (YM) High-Level Waste Repository in Nevada, proposed by the U.S. Department of Energy (DOE). The proposed YM repository would be built in a thick sequence of partially saturated volcanic tuff above the water table. Among the unique challenges of this environment are (1) the transport of radionuclides would take place partially through highly heterogeneous unsaturated rock; (2) the waste packages (WPs) would be generally exposed to oxidizing conditions, and (3) water either infiltrating from the surface or recirculating because of decay heat may drip onto the WPs. Tools such as the TPA code and embedded techniques for evaluating YM performance are aimed at (1) determining the parameters and key parts of the repository system that have the most influence on repository performance; (2) performing alternative conceptual models studies, especially with bounding models; (3) estimating the relative importance of the physical phenomena that lead to human exposure to radionuclides; and (4) improving NRC staff capabilities in performance assessment and associated license application reviews. This paper presents an overview of the NRC conceptual framework, approach to conducting system-level sensitivity analyses for determining influential parameters, and alternative conceptual model studies to investigate the effect of model uncertainties. (author)

  4. Low- and intermediate-level waste repository-induced effects

    Energy Technology Data Exchange (ETDEWEB)

    Leupin, O.X.; Marschall, P.; Johnson, L.; Cloet, V.; Schneider, J. [National Cooperative for the Disposal of Radioactive Waste (NAGRA), Wettingen (Switzerland); Smith, P. [Safety Assessment Management Ltd, Henley-On-Thames, Oxfordshire (United Kingdom); Savage, D. [Savage Earth Associates Ltd, Bournemouth, Dorset (United Kingdom); Senger, R. [Intera Inc., Ennetbaden (Switzerland)

    2016-10-15

    system has been designed to perform with sufficient safety margin for a range of siting conditions. The barriers include the host rock, its surrounding geological setting, the waste forms, drums and the cementitious backfill. They have a range of attributes that intrinsically favour safety and that avoid or minimise detrimental phenomena and uncertainties or mitigate their effects. Nevertheless, potentially detrimental repository-induced effects remain and in the present report, these are investigated and discussed considering a broad spectrum of parameters, reflecting, among other things, the range of potential siting conditions. The L/ILW emplacement caverns are designed, constructed, operated and finally backfilled in such a way that formation of excavation damaged zones is limited. Specifically this is achieved by restricting the size of the excavations and the depth of the repository, using a low-deformation, controlled construction and excavation method and by the fact that the excavations will be backfilled relatively soon after construction with grain supported mortar. At expected repository depths, the caverns will need to be supported to ensure stability and worker protection; this will prevent rock falls and further extension of the EDZ. Based on the modelling results, it can be concluded that the extent of the EDZ around the L/ILW emplacement caverns will not exceed a thickness of one cavern diameter and that the hydraulic conductance of the EDZ around the emplacement caverns, access tunnels and shafts will not exceed a value of 10{sup -7} m{sup 3}/s. Self sealing of the EDZ and low hydraulic gradients along the tunnels will result in negligible radionuclide transport by the EDZ pathway. It is shown that gas pressure build-up is controlled by the gas transport capacity of the pathways between the main repository and the access tunnel forming the so-called EGTS. Results obtained with the sensitivity cases for a repository depth of 500 m below ground level

  5. Low- and intermediate-level waste repository-induced effects

    International Nuclear Information System (INIS)

    Leupin, O.X.; Marschall, P.; Johnson, L.; Cloet, V.; Schneider, J.; Smith, P.; Savage, D.; Senger, R.

    2016-10-01

    system has been designed to perform with sufficient safety margin for a range of siting conditions. The barriers include the host rock, its surrounding geological setting, the waste forms, drums and the cementitious backfill. They have a range of attributes that intrinsically favour safety and that avoid or minimise detrimental phenomena and uncertainties or mitigate their effects. Nevertheless, potentially detrimental repository-induced effects remain and in the present report, these are investigated and discussed considering a broad spectrum of parameters, reflecting, among other things, the range of potential siting conditions. The L/ILW emplacement caverns are designed, constructed, operated and finally backfilled in such a way that formation of excavation damaged zones is limited. Specifically this is achieved by restricting the size of the excavations and the depth of the repository, using a low-deformation, controlled construction and excavation method and by the fact that the excavations will be backfilled relatively soon after construction with grain supported mortar. At expected repository depths, the caverns will need to be supported to ensure stability and worker protection; this will prevent rock falls and further extension of the EDZ. Based on the modelling results, it can be concluded that the extent of the EDZ around the L/ILW emplacement caverns will not exceed a thickness of one cavern diameter and that the hydraulic conductance of the EDZ around the emplacement caverns, access tunnels and shafts will not exceed a value of 10 -7 m 3 /s. Self sealing of the EDZ and low hydraulic gradients along the tunnels will result in negligible radionuclide transport by the EDZ pathway. It is shown that gas pressure build-up is controlled by the gas transport capacity of the pathways between the main repository and the access tunnel forming the so-called EGTS. Results obtained with the sensitivity cases for a repository depth of 500 m below ground level indicate that

  6. INSTITUTIONAL REPOSITORY: EMPLOYMENT IN EDUCATION

    Directory of Open Access Journals (Sweden)

    Vasyl P. Oleksyuk

    2012-11-01

    Full Text Available The article investigated the concept of «institutional repository» and determined the aspects of institutional repositories in higher education. Institutional Repositories are information systems that allow preserving, storing and disseminating scientific knowledge produced in higher education and scientific research institutions. This study presented the main aspects using institutional repositories in educational process (such as storage of scientific and educational information, means of organization activity of students, object of studying. This article produced the structure of communities and collections of the institutional. It is described the experience of implementing of DSpace in the learning process.

  7. Trust in Digital Repositories

    Directory of Open Access Journals (Sweden)

    Elizabeth Yakel

    2013-06-01

    Full Text Available ISO 16363:2012, Space Data and Information Transfer Systems - Audit and Certification of Trustworthy Digital Repositories (ISO TRAC, outlines actions a repository can take to be considered trustworthy, but research examining whether the repository’s designated community of users associates such actions with trustworthiness has been limited. Drawing from this ISO document and the management and information systems literatures, this paper discusses findings from interviews with 66 archaeologists and quantitative social scientists. We found similarities and differences across the disciplines and among the social scientists. Both disciplinary communities associated trust with a repository’s transparency. However, archaeologists mentioned guarantees of preservation and sustainability more frequently than the social scientists, who talked about institutional reputation. Repository processes were also linked to trust, with archaeologists more frequently citing metadata issues and social scientists discussing data selection and cleaning processes. Among the social scientists, novices mentioned the influence of colleagues on their trust in repositories almost twice as much as the experts. We discuss the implications our findings have for identifying trustworthy repositories and how they extend the models presented in the management and information systems literatures.

  8. A new methodology for repository site suitability evaluation

    International Nuclear Information System (INIS)

    Miller, I.; Kossik, R.; Cunnane, M.

    1992-01-01

    Golder Associates Inc. (GAI) has developed a probabilistic total system performance assessment and strategy evaluation model (RIP) which can be applied in an iterative manner to evaluate repository site suitability and guide site characterization. The major portion of the software is the performance assessment model, which consists of a series of coupled component models for radionuclide transfer. The performance model itself is embedded within a decision analysis model which allows the user to evaluate alternative site characterization strategies. This paper provides an overview of the methodology, and summarizes the basic concepts of RIP

  9. Desiderata for healthcare integrated data repositories based on architectural comparison of three public repositories.

    Science.gov (United States)

    Huser, Vojtech; Cimino, James J

    2013-01-01

    Integrated data repositories (IDRs) are indispensable tools for numerous biomedical research studies. We compare three large IDRs (Informatics for Integrating Biology and the Bedside (i2b2), HMO Research Network's Virtual Data Warehouse (VDW) and Observational Medical Outcomes Partnership (OMOP) repository) in order to identify common architectural features that enable efficient storage and organization of large amounts of clinical data. We define three high-level classes of underlying data storage models and we analyze each repository using this classification. We look at how a set of sample facts is represented in each repository and conclude with a list of desiderata for IDRs that deal with the information storage model, terminology model, data integration and value-sets management.

  10. Salt Repository Project transportation program plan

    International Nuclear Information System (INIS)

    Fisher, R.L.; Greenberg, A.H.; Anderson, T.L.; Yates, K.R.

    1987-01-01

    The Salt Repository Project (SRP) has the responsibility to develop a comprehensive transportation program plan (TrPP) that treats the transportation of workers, supplies, and high-level radioactive waste to the site and the transportation of salt, low-level, and transuranic wastes from the site. The TrPP has developed a systematic approach to transportation which is directed towards satisfying statutes, regulations, and directives and is guided by a hierarchy of specific functional requirements, strategies, plans, and reports. The TrPP identifies and develops the planning process for transportation-related studies and provides guidance to staff in performing and documenting these activities. The TrPP also includes an explanation of the responsibilities of the organizational elements involved in these transportation studies. Several of the report chapters relate to identifying routes for transporting nuclear waste to the site. These include a chapter on identifying an access corridor for a new rail route leading to the site, identifying and evaluating emergency-response preparedness capabilities along candidate routes in the state, and identifying alternative routes from the state border, ports, or in-state reactors to the site. The TrPP also includes plans for identifying salt disposal routes and a discussion of repository/transportation interface requirements. 89 refs., 6 figs

  11. The Ec prototype repository project: implications of assessments for refining repository design

    International Nuclear Information System (INIS)

    Svemar, C.

    2004-01-01

    The most important issue in the evaluation of the repository performance is the long term safety of the repository. Analyses for this issue focuses on the 'steady state' conditions which start at the time when the repository has been saturated and the groundwater table returned to its normal level. The bentonite buffer around the canisters is saturated and homogeneous, and the canister is located exactly in the centre of the buffer. The backfill in the tunnel has been saturated as well and fills the earlier open spaces in the tunnel completely. The task of the activities taking places prior to the start of the 'steady state' conditions, like excavation, deposition, backfilling and sealing, with due consideration to the processes a consequences they may cause in the long run, is to provide for these 'ideal' conditions, as close as possible. While studying these activities in detail it has become obvious that development of methods and techniques needs to be carefully addressed before the decision is made on how to apply them in the repository. One general finding is that the situation in engineering of details is not that much different from the situation in geological characterisation of a site in detail; one more detail of engineering and the consequences it brings often complicates the situation rather than supports the solution prioritized so far. Many of the practical issues have been studied in the Prototype Repository project in the AEspoe Hard Rock Laboratory (Pusch et al., 2000). The Prototype Repository consists of two sections with four respectively two deposition holes with bentonite buffer and canister, the latter holding electrical heaters. The sections are separated by a concrete plug, and the whole test is to be separated from the rest of the laboratory by an outer plug. The project has two objectives: 1. To demonstrate the integrated function of tile deep repository components under realistic conditions and to compare results with models and

  12. 76 FR 12129 - Lake Champlain Sea Lamprey Control Alternatives Workgroup

    Science.gov (United States)

    2011-03-04

    ... implementation of sea lamprey control techniques alternative to lampricide that are technically feasible, cost... regarding the implementation of sea lamprey control methods alternative to lampricides, to recommend...

  13. 48 CFR 227.7108 - Contractor data repositories.

    Science.gov (United States)

    2010-10-01

    ... repositories. 227.7108 Section 227.7108 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS... Technical Data 227.7108 Contractor data repositories. (a) Contractor data repositories may be established when permitted by agency procedures. The contractual instrument establishing the data repository must...

  14. TWTF project criticality task force final review and assessment

    International Nuclear Information System (INIS)

    McKinley, K.B.; Cannon, J.W.; Wheeler, F.J.; Worle, H.A.

    1980-11-01

    The Transuranic Waste Treatment Facility (TWTF) is being developed to process transuranic waste, stored and buried at the Idaho National Engineering Laboratory, into a chemically inert, physically stable basalt-like residue acceptable at a federal repository. A task force was assembled by the TWTF Project Division to review and assess all aspects of criticality safety for the TWTF. This document presents the final review, assessments, and recommendations of this task force. The following conclusions were made: Additional criticality studies are needed for the entire envelope of feed compositions and temperature effects. Safe operating k/sub eff/'s need to be determined for process components. Criticality analyses validation experiments may also be required. SRP neutron interrogation should be replaced by DDT neutron interrogation. Accuracy studies need to be performed for the proposed assaying techniques. Time-correlated neutron monitoring needs to be mocked up for process components to prove feasibility and determine accuracy. The criticality control techniques developed for the TWTF conceptual design are in compliance with ERDAM 0530, including the Double Contingency Rule. Detailed procedures and controls need to be developed

  15. NPP Krsko: LILW Repository or Long Term Storage

    International Nuclear Information System (INIS)

    Lokner, V.; Subasic, D.; Levanat, I.

    2008-01-01

    output; introducing the possibility for less robust LILW repository construction or shorter period of institutional control; shortening the operational period for LILW repository; allowing for potential benefits from technological or any other progress in waste management (including various prospects such as regional repository, reprocessing etc.); and, perhaps, exploiting the advantages of potential development of nuclear programs in Slovenia or Croatia.(author)

  16. Deep repository for long-lived low- and intermediate-level waste. Preliminary safety assessment

    International Nuclear Information System (INIS)

    1999-11-01

    A preliminary safety assessment has been performed of a deep repository for long-lived low- and intermediate-level waste, SFL 3-5. The purpose of the study is to investigate the capacity of the facility to act as a barrier to the release of radionuclides and toxic pollutants, and to shed light on the importance of the location of the repository site. A safety assessment (SR 97) of a deep repository for spent fuel has been carried out at the same time. In SR 97, three hypothetical repository sites have been selected for study. These sites exhibit fairly different conditions in terms of hydrogeology, hydrochemistry and ecosystems. To make use of information and data from the SR 97 study, we have assumed that SFL 3-5 is co-sited with the deep repository for spent fuel. A conceivable alternative is to site SFL 3-5 as a completely separate repository. The focus of the SFL 3-5 study is a quantitative analysis of the environmental impact for a reference scenario, while other scenarios are discussed and analyzed in more general terms. Migration in the repository's near- and far-field has been taken into account in the reference scenario. Environmental impact on the three sites has also been calculated. The calculations are based on an updated forecast of the waste to be disposed of in SFL 3-5. The forecast includes radionuclide content, toxic metals and other substances that have a bearing on a safety assessment. The safety assessment shows how important the site is for safety. Two factors stand out as being particularly important: the water flow at the depth in the rock where the repository is built, and the ecosystem in the areas on the ground surface where releases may take place in the future. Another conclusion is that radionuclides that are highly mobile and long-lived, such as 36 Cl and 93 Mo , are important to take into consideration. Their being long-lived means that barriers and the ecosystems must be regarded with a very long time horizon

  17. 76 FR 43698 - Lake Champlain Sea Lamprey Control Alternatives Workgroup

    Science.gov (United States)

    2011-07-21

    ... implementation of sea lamprey control techniques alternative to lampricide that are technically feasible, cost... provide advice regarding the implementation of sea lamprey control methods alternative to lampricides, to...

  18. Evaluation of the effectiveness and feasibility of the Waste Isolation Pilot Plant engineered alternatives: Final report of the Engineered Alternatives Task Force

    International Nuclear Information System (INIS)

    1991-07-01

    The Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico, is an underground repository designed for the geologic disposal of radioactive wastes resulting from the defense activities and programs of the United States Department of Energy (DOE). The performance of nuclear waste repositories is governed by US Environmental Protection Agency (EPA). The study conducted to demonstrate compliance with this regulation is called performance assessment. The EPA standard requires that DOE provide a reasonable assurance, based on performance assessment, that cumulative releases of radioactivity to the accessible environment will not exceed the standard's criteria. Preliminary performance assessment performed by SNL has indicated that the current design of the WIPP repository, together with the waste forms at the DOE storage and generating sites, may not demonstrate compliance with the EPA Standard. In view of this concern, and prompted by recommendations from external review groups, the DOE established the Engineered Alternatives Task Force (EATF) in September, 1989. The objective of the EATF is to identify potential engineering modifications (referred to as engineered alternatives) to the existing WIPP design and/or to the transuranic (TRU) waste forms, an to evaluate their effectiveness and feasibility in facilitating compliance with the EPA Standard. These alternatives would be designed to completely eliminate or reduce any problems which might cause non-compliance with the EPA Standard. 139 refs., 39 figs., 124 tabs

  19. A control volume scheme for three-dimensional transport: buffer and matrix effect on a decay chain transport in the repository

    International Nuclear Information System (INIS)

    Lee, Y. M.; Hwang, Y. S.; Kim, S. G.; Kang, C. H.

    2002-01-01

    Using a three-dimensional numerical code, B3R developed for nuclide transport of an arbitrary length of decay chain in the buffer between the canister and adjacent rock in a high-level radioactive waste repository by adopting a finite difference method utilizing the control-volume scheme, some illustrative calculations have been done. A linear sorption isotherm, nuclide transport due to diffusion in the buffer and the rock matrix, and advection and dispersion along thin rigid parallel fractures existing in a saturated porous rock matrix as well as diffusion through the fracture wall into the matrix is assumed. In such kind of repository, buffer and rock matrix are known to be important physico-chemical barriers in nuclide retardation. To show effects of buffer and rock matrix on nuclide transport in HLW repository and also to demonstrate usefulness of B3R, several cases of breakthrough curves as well as three-dimensional plots of concentration isopleths associated with these two barriers are introduced for a typical case of decay chain of 234 U→ 230 Th→ 226 Ra, which is the most important chain as far as the human environment is concerned

  20. National Radwaste Repository Mochovce

    International Nuclear Information System (INIS)

    2000-01-01

    In this leaflet the National Radioactive Waste Repository in Mochovce (Repository) is described. The Mochovce National Radioactive Waste Repository is a surface multi-barrier type storage facility for solid and treated solidified radioactive wastes generated from the Slovak Republic nuclear power plants operation and decommissioning, research institutes, laboratories and hospitals. The Repository comprises a system of single- and double-row storage boxes. The first double-row is enclosed by a steel-structure building. The 18 x 6 x 5.5 m storage boxes are made of reinforced concrete. The wall thickness is 600 mm. Two-double-rows, i.e. 80 storage boxes were built as part of Stage I (1 row = 20 storage boxes). Each storage box has a storage capacity of 90 fibre concrete containers of 3.1 m 3 volume. The total storage capacity is 7200 containers with the overall storage volume of 22320 m 3

  1. Analysis of Turkey’s Institutional Open Repositories: An Example of Dokuz Eylül University Institutional Open Repository

    Directory of Open Access Journals (Sweden)

    Korhan Levent Ertürk

    2012-03-01

    Full Text Available After the declaration of the Budapest Open Access Initiative in 2001, institutional open repositories are known as the most important tool of the self archiving, which is also known as green road. There are 26 institutional repositories, which are all compatible to international standards. All the institutional open repositories of Turkey mentioned before are listed in international open archive directories. In this study institutional open repository of Dokuz Eylül University is examined and institutional open repositories of Turkey are discussed.

  2. Radioactive waste repository of high ecological safety

    International Nuclear Information System (INIS)

    Sobolev, I.; Barinov, A.; Prozorov, L.

    2000-01-01

    With the purpose to construct a radioactive waste repository of high ecological safety and reliable containment, MosNPO 'Radon' specialists have developed an advanced type repository - large diameter well (LBD) one. A project is started for the development of a technology for LDW repository construction and pilot operation of the new repository for 25-30 years. The 2 LDW repositories constructed at the 'Radon' site and the developed monitoring system are described

  3. An assessment of the radiological impact of coastal erosion of the UK Low-Level Waste Repository - 59137

    International Nuclear Information System (INIS)

    Sumerling, Trevor; Shevelan, John; Cummings, Richard; Fish, Paul; Towler, George; Penfold, James

    2012-01-01

    The UK Low Level Waste Repository Ltd submitted an Environmental Safety Case for the disposal of low-level waste to our regulator, the Environment Agency, on the 1 May 2011. This includes assessments of the long-term radiological safety of past and future disposals. A particular feature of the Low Level Waste Repository (LLWR) is that, because of its proximity to the coast, the site is vulnerable to coastal erosion. Our present understanding is that the site will be eroded on a timescale of a few hundred to a few thousand years, with consequent disruption of the repository, and dispersal of the wastes. We have undertaken a programme of scientific research and monitoring to characterise the evolution and function of the current coastal system that provides a basis for forecasting its future evolution. This has included modelling of contemporary hydrodynamics, geo-morphological mapping, repeat LiDAR and aerial photographic surveys to detect patterns and rates of change, coastal inspections and reconstructions of post-glacial (i.e. last 15, 000 years) sea levels and sediment budgets. Estimates of future sea-level rise have been derived from international sources and consideration given to the impact of such on the local coastline. Two alternative models of coastal recession have then been applied, one empirical and one physical-process based, taking account of the composition of Quaternary-age sediments between the coast and the site and uncertainties in future local sea level change. Comparison of the ranges of calculated times to site contact with sea-level rise indicate that the repository is most likely to be disrupted by undercutting of the engineered vaults and of the trenches. A novel and flexible radiological assessment model has been developed to analyse the impacts of the erosion of the repository and subsequent dispersal of wastes. The model represents the spatial layout of the site and distribution of radionuclides within the repository and is able to take

  4. The Proposed Yucca Mountain Repository From A Corrosion Perspective

    International Nuclear Information System (INIS)

    J.H. Payer

    2005-01-01

    Corrosion is a primary determinant of waste package performance at the proposed Yucca Mountain Repository and will control the delay time for radionuclide transport from the waste package. Corrosion is the most probable and most likely degradation process that will determine when packages will be penetrated and the shape size and distribution of those penetrations. The general issues in corrosion science, materials science and electrochemistry are well defined, and the knowledge base is substantial for understanding corrosion processes. In this paper, the Yucca Mountain Repository is viewed from a corrosion perspective

  5. Consistency analysis of network traffic repositories

    NARCIS (Netherlands)

    Lastdrager, Elmer; Lastdrager, E.E.H.; Pras, Aiko

    Traffic repositories with TCP/IP header information are very important for network analysis. Researchers often assume that such repositories reliably represent all traffic that has been flowing over the network; little thoughts are made regarding the consistency of these repositories. Still, for

  6. Supplemental Performance Analyses for Igneous Activity and Human Intrusion at the Potential High-Level Nuclear Waste Repository at Yucca Mountain

    International Nuclear Information System (INIS)

    Swift, P.; Gaither, K.; Freeze, G.; McCord, J.; Kalinich, D.; Saulnier, G.; Statham, W.

    2002-01-01

    The U.S. Department of Energy (DOE) is considering the possible recommendation of a site at Yucca Mountain, Nevada, for the potential development of a geologic repository for the disposal of high-level radioactive waste and spent nuclear fuel. Consequences of hypothetical disruption of the Yucca Mountain site by igneous activity or human intrusion have been evaluated in the Yucca Mountain Science and Engineering Report (S and ER) (1), which presents technical information supporting the consideration of the possible site recommendation. Since completion of the S and ER, supplemental analyses have examined possible impacts of new information and alternative assumptions on the estimates of the consequences of these events. Specifically, analyses of the consequences of igneous disruption address uncertainty regarding: (1) the impacts of changes in the repository footprint and waste package spacing on the probability of disruption; (2) impacts of alternative assumptions about the appropriate distribution of future wind speeds to use in the analysis; (3) effects of alternative assumptions about waste particle sizes; and (4) alternative assumptions about the number of waste packages damaged by igneous intrusion; and (5) alternative assumptions about the exposure pathways and the biosphere dose conversion factors used in the analysis. Additional supplemental analyses, supporting the Final Environmental Impact Statement (FEIS), have examined the results for both igneous disruption and human intrusion, recalculated for a receptor group located 18 kilometers (km) from the repository (the location specified in 40 CFR 197), rather than at the 20 km distance used in the S and ER analyses

  7. Sellafield repository design concept

    International Nuclear Information System (INIS)

    1998-01-01

    Between 1989 and 1997, UK Nirex Ltd carried out a programme of investigations to evaluate the potential of a site adjacent to the BNFL Sellafield works to host a deep repository for the United Kingdom's intermediate-level and certain low-level radioactive waste. The programme of investigations was wound down following the decision in March 1997 to uphold the rejection of the Company's planning application for the Rock Characterisation Facility (RCF), an underground laboratory which would have allowed further investigations to confirm whether or not the site would be suitable. Since that time, the Company's efforts in relation to the Sellafield site have been directed towards documenting and publishing the work carried out. The design concept for a repository at Sellafield was developed in parallel with the site investigations through an iterative process as knowledge of the site and understanding of the repository system performance increased. This report documents the Sellafield repository design concept as it had been developed, from initial design considerations in 1991 up to the point when the RCF planning application was rejected. It shows, from the context of a project at that particular site, how much information and experience has been gained that will be applicable to the development of a deep waste repository at other potential sites

  8. Robust record preservation system on geological repository

    International Nuclear Information System (INIS)

    Ohuchi, J.; Torata, S.; Tsuboya, T.

    2004-01-01

    Long-term record preservation system on geological disposal of High Level Radioactive Wastes (HLW) has been investigated as the institutional control by RWMC, Japan. Geological disposal of HLW, being based on the passive safe concept, has been considered not to necessitate the human controls to maintain its long-term safety. However how to complement the safety case on geological disposal is an important issue in each countries to progress the repository program with the step-wise decisions process during the long-term period up to several hundreds years. Although we cannot predict the future society, we need to realize the robust and redundant system for preserving records, which should be accessible, retrievable and understandable for the unpredicted future generations. First of all, we held a Rome workshop in January 2003 to exchange views on the matter, resulted in the suggestion directing the discussion on the record management and long-term preservation and retrieval of information regarding radioactive waste. Second, we considered the balance of active and passive system to strengthen the robustness. Another significance of long-term record preservation is to send current generation an implicit message, 'doing our best for future generations', in addition to aiming at both warning and their own decision-making. We call it 'meta-signal' to current generation. Thirdly, we demonstrated the laser-engraving technology to have converted five hundreds pages of an A4 sized report with human readable font sizes to 42 square silicon carbide plates, 10cm x10cm and 1mm in thickness. Silicon carbide would be an alternative to paper and might be possible to be an alternative to microfilm utilized as digital recording media. Another case study is the future generations' accessibility to the preserved records. (author)

  9. Influence analysis of Github repositories.

    Science.gov (United States)

    Hu, Yan; Zhang, Jun; Bai, Xiaomei; Yu, Shuo; Yang, Zhuo

    2016-01-01

    With the support of cloud computing techniques, social coding platforms have changed the style of software development. Github is now the most popular social coding platform and project hosting service. Software developers of various levels keep entering Github, and use Github to save their public and private software projects. The large amounts of software developers and software repositories on Github are posing new challenges to the world of software engineering. This paper tries to tackle one of the important problems: analyzing the importance and influence of Github repositories. We proposed a HITS based influence analysis on graphs that represent the star relationship between Github users and repositories. A weighted version of HITS is applied to the overall star graph, and generates a different set of top influential repositories other than the results from standard version of HITS algorithm. We also conduct the influential analysis on per-month star graph, and study the monthly influence ranking of top repositories.

  10. MRS/IS facility co-located with a repository: preconceptual design and life-cycle cost estimates

    International Nuclear Information System (INIS)

    Smith, R.I.; Nesbitt, J.F.

    1982-11-01

    A program is described to examine the various alternatives for monitored retrievable storage (MRS) and interim storage (IS) of spent nuclear fuel, solidified high-level waste (HLW), and transuranic (TRU) waste until appropriate geologic repository/repositories are available. The objectives of this study are: (1) to develop a preconceptual design for an MRS/IS facility that would become the principal surface facility for a deep geologic repository when the repository is opened, (2) to examine various issues such as transportation of wastes, licensing of the facility, and environmental concerns associated with operation of such a facility, and (3) to estimate the life cycle costs of the facility when operated in response to a set of scenarios which define the quantities and types of waste requiring storage in specific time periods, which generally span the years from 1990 until 2016. The life cycle costs estimated in this study include: the capital expenditures for structures, casks and/or drywells, storage areas and pads, and transfer equipment; the cost of staff labor, supplies, and services; and the incremental cost of transporting the waste materials from the site of origin to the MRS/IS facility. Three scenarios are examined to develop estimates of life cycle costs of the MRS/IS facility. In the first scenario, HLW canisters are stored, starting in 1990, until the co-located repository is opened in the year 1998. Additional reprocessing plants and repositories are placed in service at various intervals. In the second scenario, spent fuel is stored, starting in 1990, because the reprocessing plants are delayed in starting operations by 10 years, but no HLW is stored because the repositories open on schedule. In the third scenario, HLW is stored, starting in 1990, because the repositories are delayed 10 years, but the reprocessing plants open on schedule

  11. Nurse attitudes towards the use of complementary and alternative therapies in critical care.

    Science.gov (United States)

    Tracy, Mary Fran; Lindquist, Ruth; Watanuki, Shigeaki; Sendelbach, Sue; Kreitzer, Mary Jo; Berman, Brian; Savik, Kay

    2003-01-01

    There is increasing demand for complementary/alternative therapies (CAT) in critical care, however, critical care nurses' perspectives regarding CAT are unknown. This study was conducted to determine critical care nurses' knowledge, attitudes, and use of CAT. A total of 348 critical care registered nurses working at least 40% in medical, surgical, cardiac, neurological, and pediatric ICUs at 2 tertiary-level hospitals in a large Midwestern city were surveyed. One hospital is a 926-bed private, urban hospital and the second is an 1868-bed academic-affiliated medical center. A survey was distributed to all critical care nurses described above. The level of knowledge reported by 138 nurse respondents was greatest for diet, exercise, massage, prayer, and music therapy. Use of therapies was related to knowledge and training and consistent with beliefs of legitimacy and perceptions of beneficial effects. Despite barriers including lack of knowledge, time, and training, 88% of respondents were open or eager to use CAT, and 60% reported moderate or greater desire to use CAT. Critical care nurses are open to CAT use and many use them in their own practice. Because use was associated with knowledge, recommendations for future research include increasing the scientific base and enhancing knowledge to promote evidence-based incorporation of CAT in practice.

  12. Use of limited information in a license application to construct a repository

    International Nuclear Information System (INIS)

    McGarry, J.M. III; Echols, F.S.

    1996-01-01

    The purpose of this paper is to provide a rationale for the proposition that the Department of Energy's (DOE's) submittal of a license application (LA) for the construction of a geologic repository to the Nuclear Regulatory Commission (NRC) may be, and arguably must be, based on statutorily-limited site characterization data and design information. The Nuclear Waste Policy Act of 1982 (NWPA), as amended, is the controlling statute for the disposal of spent nuclear fuel in a licensed geologic repository. Applicable NRC regulations for the licensing of such a repository are found for the most part in 10 C.F.R. Part 60

  13. CRIS and Institutional Repositories

    Directory of Open Access Journals (Sweden)

    A Asserson

    2010-04-01

    Full Text Available CRIS (Current Research Information Systems provide researchers, research managers, innovators, and others with a view over the research activity of a domain. IRs (institutional repositories provide a mechanism for an organisation to showcase through OA (open access its intellectual property. Increasingly, organizations are mandating that their employed researchers deposit peer-reviewed published material in the IR. Research funders are increasingly mandating that publications be deposited in an open access repository: some mandate a central (or subject-based repository, some an IR. In parallel, publishers are offering OA but replacing subscription-based access with author (or author institution payment for publishing. However, many OA repositories have metadata based on DC (Dublin Core which is inadequate; a CERIF (Common-European Research Information Format CRIS provides metadata describing publications with formal syntax and declared semantics thus facilitating interoperation or homogeneous access over heterogeneous sources. The formality is essential for research output metrics, which are increasingly being used to determine future funding for research organizations.

  14. Parametric Optimization of Some Critical Operating System Functions--An Alternative Approach to the Study of Operating Systems Design

    Science.gov (United States)

    Sobh, Tarek M.; Tibrewal, Abhilasha

    2006-01-01

    Operating systems theory primarily concentrates on the optimal use of computing resources. This paper presents an alternative approach to teaching and studying operating systems design and concepts by way of parametrically optimizing critical operating system functions. Detailed examples of two critical operating systems functions using the…

  15. Draft environmental impact statement. High-level waste repository site suitability criteria

    International Nuclear Information System (INIS)

    1978-01-01

    The purpose of HLWRSSC is to present guidelines which will help in the development of safe waste management schemes. Current regulations require solidification of all high-level waste within 5 years of their generation and transfer to a Federal waste repository within 10 years. Development of the proposed HLWRSSC is part of the overall NRC program to close the ''back end'' of the commercial LWR fuel cycle. In this document, the need for the HLWRSSC is reviewed, and the national energy policy, the need for electrical energy, and the nuclear fuel cycle are discussed. Considerations for HLWRSSC are presented, including the nature of the repository, important site-related factors, and radiological risk assessment methodology. Radiological and nonradiological environment impacts associated with the HLWRSSC are defined. Alternatives to the criteria are presented, and the cost-benefit-risk evaluation is reviewed

  16. Progress on the national low level radioactive waste repository and national intermediate level waste store

    International Nuclear Information System (INIS)

    Perkins, C.

    2001-01-01

    Over the last few years, significant progress has been made towards siting national, purpose-built facilities for Australian radioactive waste. In 2001, after an eight year search, a preferred site and two alternatives were identified in central-north South Australia for a near-surface repository for Australian low level (low level and short-lived intermediate level) radioactive waste. Site 52a at Everts Field West on the Woomera Prohibited Area was selected as the preferred site as it performs best against the selection criteria, particularly with respect to geology, ground water, transport and security. Two alternative sites, Site 45a and Site 40a, east of the Woomera-Roxby Downs Road, were also found to be highly suitable for the siting of the national repository. A project has commenced to site a national store for intermediate (long-lived intermediate level) radioactive waste on Commonwealth land for waste produced by Commonwealth agencies. Public input has been sought on relevant selection criteria

  17. Selection of candidate canister materials for high-level nuclear waste containment in a tuff repository

    International Nuclear Information System (INIS)

    McCright, R.D.; Weiss, H.; Juhas, M.C.; Logan, R.W.

    1983-11-01

    A repository located at Yucca Mountain at the Nevada Test Site is a potential site for permanent geological disposal of high-level nuclear waste. The repository can be located in a horizon in welded tuff, a volcanic rock, which is above the static water level at this site. The environmental conditions in this unsaturated zone are expected to be air and water vapor dominated for much of the containment period. Type 304L stainless steel is the reference material for fabricating canisters to contain the solid high-level wastes. Alternative stainless alloys are considered because of possible susceptibility of 304L to localized and stress forms of corrosion. For the reprocessed glass wastes, the canisters serve as the recipient for pouring the glass with the result that a sensitized microstructure may develop because of the times at elevated temperatures. Corrosion testing of the reference and alternative materials has begun in tuff-conditioned water and steam environments. 21 references, 8 figures, 8 tables

  18. Radionuclide transport in the repository near-field and far-field

    International Nuclear Information System (INIS)

    Poteri, A.; Nordman, H.; Pulkkanen, V.-M.; Smith, P.

    2014-01-01

    This report is a background report of the TURVA-2012 safety case report 'Assessment of Radionuclide Release Scenarios for the Repository System'. This report gives a comprehensive account of the modelling of radionuclide release from a defective canister and the subsequent migration to the surface groundwater system. The focus of this report is in the radionuclide migration both in the repository near-field and in the repository far-field. Radionuclide releases from the canister and migration through the repository near-field and far-field have also been analysed in the probabilistic sensitivity analysis based on the Monte Carlo simulation method. Those simulations are discussed in a separate report by Cormenzana. Calculation cases are derived from three different types of scenarios: (i) The base scenario that assumes a single initially defective canister located in a cautiously selected canister position, i.e. selecting the failed canister location such that radionuclide release and transport properties are conservative compared to the statistics over all canister locations. Migration processes and parameter values follow the most likely lines of evolution. Repository safety functions are assumed to perform according to the design basis. Calculation cases defined in the Assessment of Radionuclide Release Scenarios report are also supplemented by additional calculation cases that are aimed to study variability between different DFN realisations (additional BS-ALL cases), longitudinal dispersion (BS-RC-ld cases) and alternative realisations of the transport classes along the release paths (BS-RC-tc cases), (ii) Variant scenarios that study declined performance of the repository safety functions. These include enhanced corrosion failure and degradation of the buffer under variant geochemical conditions (iii) Disturbance scenarios that analyse influences of unlikely events on the radionuclide release and migration. Analysis of the variant and disturbance scenarios

  19. Nuclear waste repository design and construction

    International Nuclear Information System (INIS)

    Bohlke, B.M.; Monsees, J.E.

    1987-01-01

    Extensive underground excavation will be required for construction of a mined geologic repository for nuclear waste. Hundreds of thousands of feet of drift will be required based on the conceptual layout design for each candidate nuclear waste repository. Comparison of boring and blasting excavation methods are discussed, as are special design and construction requirements (e.g., quality assurance procedures and performance assessment) for the nuclear waste repository. Comparisons are made between boring and blasting construction methods for the repository designs proposed for salt, volcanic tuff, and basalt

  20. Benefit-cost-risk analysis of alternatives for greater-confinement disposal of radioactive waste

    International Nuclear Information System (INIS)

    Gilbert, T.L.; Luner, C.; Peterson, J.M.

    1983-01-01

    Seven alternatives are included in the analysis: near-surface disposal; improved waste form; below-ground engineered structure; augered shaft; shale fracturing; shallow geologic repository; and high-level waste repository. These alternatives are representative generic facilities that span the range from low-level waste disposal practice to high-level waste disposal practice, tentatively ordered according to an expected increasing cost and/or effectiveness of confinement. They have been chosen to enable an assessment of the degree of confinement that represents an appropriate balance between public health and safety requirements and costs rather than identification of a specific preferred facility design. The objective of the analysis is to provide a comparative ranking of the alternatives on the basis of benefit-cost-risk considerations

  1. Impact of repository depth on residence times for leaking radionuclides in land-based surface water

    Science.gov (United States)

    Wörman, Anders; Marklund, Lars; Xu, Shulan; Dverstorp, Björn

    2007-03-01

    The multiple scales of landscape topography produce a wide distribution of groundwater circulation cells that control the hydro-geological environments surrounding geological repositories for nuclear waste. The largest circulation cells tend to discharge water into major river reaches, large freshwater systems or the nearby Baltic Sea. We investigated numerically the release of radionuclides from repositories placed in bedrock with depths between 100 to 2000 meters in a Swedish coastal area and found that leakage from the deeper positions emerges primarily in the major aquatic systems. In effect, radionuclides from the deeper repositories are more rapidly transported towards the Sea by the stream system compared to leakage from more shallow repositories. The release from the shallower repositories is significantly retained in the initial stage of the transport in the (superficial) landscape because the discharge occurs in or near low-order streams with high retention characteristics. This retention and residence time for radioactivity in the landscape control radiological doses to biota and can, thus, be expected to constitute an essential part of an associated risk evaluation.

  2. Alternator control for battery charging

    Energy Technology Data Exchange (ETDEWEB)

    Brunstetter, Craig A.; Jaye, John R.; Tallarek, Glen E.; Adams, Joseph B.

    2015-07-14

    In accordance with an aspect of the present disclosure, an electrical system for an automotive vehicle has an electrical generating machine and a battery. A set point voltage, which sets an output voltage of the electrical generating machine, is set by an electronic control unit (ECU). The ECU selects one of a plurality of control modes for controlling the alternator based on an operating state of the vehicle as determined from vehicle operating parameters. The ECU selects a range for the set point voltage based on the selected control mode and then sets the set point voltage within the range based on feedback parameters for that control mode. In an aspect, the control modes include a trickle charge mode and battery charge current is the feedback parameter and the ECU controls the set point voltage within the range to maintain a predetermined battery charge current.

  3. Implementing and Sustaining Data Lifecycle best Practices: a Framework for Researchers and Repositories

    Science.gov (United States)

    Stall, S.

    2016-02-01

    Emerging data management mandates in conjunction with cross-domain international interoperability are posing new challenges for researchers and repositories. Domain repositories are serving in this critical, growing role monitoring and leading data management standards and capability within their own repository and working on mappings between repositories internationally. Leading research institutions and companies will also be important as they develop and expand data curation efforts. This landscape poses a number of challenges for developing and ensuring the use of best practices in curating research data, enabling discovery, elevating quality across diverse repositories, and helping researchers collect and organize it through the full data life cycle. This multidimensional challenge will continue to grow in complexity. The American Geophysical Union (AGU) is developing two programs to help researchers and data repositories develop and elevate best practices and address these challenges. The goal is to provide tools for the researchers and repositories, whether domain, institutional, or other, that improve performance throughout the data lifecycle across the Earth and space science community. For scientists and researchers, AGU is developing courses around handling data that can lead toward a certification in geoscience data management. Course materials will cover metadata management and collection, data analysis, integration of data, and data presentation. The course topics are being finalized by the advisory board with the first one planned to be available later this year. AGU is also developing a program aimed at helping data repositories, large and small, domain-specific to general, assess and improve data management practices. AGU has partnered with the CMMI® Institute to adapt their Data Management Maturity (DMM)SM framework within the Earth and space sciences. A data management assessment using the DMMSM involves identifying accomplishments and

  4. National radioactive wasterRepository Mochovce

    International Nuclear Information System (INIS)

    2000-01-01

    In this leaflet the scheme of the Mochovce National radioactive waste repository for the Slovak Republic is presented. The National radioactive waste repository in Mochovce is a surface type storage facility. It is intended for final disposal of solid and solidified low and intermediate radioactive waste produced during the operation of nuclear power plants and institutions located within the territory of the Slovak Republic. The Repository site is situated about 2 km northwest to the Mochovce NPP

  5. Data Publishing and Sharing Via the THREDDS Data Repository

    Science.gov (United States)

    Wilson, A.; Caron, J.; Davis, E.; Baltzer, T.

    2007-12-01

    The terms "Team Science" and "Networked Science" have been coined to describe a virtual organization of researchers tied via some intellectual challenge, but often located in different organizations and locations. A critical component to these endeavors is publishing and sharing of content, including scientific data. Imagine pointing your web browser to a web page that interactively lets you upload data and metadata to a repository residing on a remote server, which can then be accessed by others in a secure fasion via the web. While any content can be added to this repository, it is designed particularly for storing and sharing scientific data and metadata. Server support includes uploading of data files that can subsequently be subsetted, aggregrated, and served in NetCDF or other scientific data formats. Metadata can be associated with the data and interactively edited. The THREDDS Data Repository (TDR) is a server that provides client initiated, on demand, location transparent storage for data of any type that can then be served by the THREDDS Data Server (TDS). The TDR provides functionality to: * securely store and "own" data files and associated metadata * upload files via HTTP and gridftp * upload a collection of data as single file * modify and restructure repository contents * incorporate metadata provided by the user * generate additional metadata programmatically * edit individual metadata elements The TDR can exist separately from a TDS, serving content via HTTP. Also, it can work in conjunction with the TDS, which includes functionality to provide: * access to data in a variety of formats via -- OPeNDAP -- OGC Web Coverage Service (for gridded datasets) -- bulk HTTP file transfer * a NetCDF view of datasets in NetCDF, OPeNDAP, HDF-5, GRIB, and NEXRAD formats * serving of very large volume datasets, such as NEXRAD radar * aggregation into virtual datasets * subsetting via OPeNDAP and NetCDF Subsetting services This talk will discuss TDR

  6. Biological Web Service Repositories Review.

    Science.gov (United States)

    Urdidiales-Nieto, David; Navas-Delgado, Ismael; Aldana-Montes, José F

    2017-05-01

    Web services play a key role in bioinformatics enabling the integration of database access and analysis of algorithms. However, Web service repositories do not usually publish information on the changes made to their registered Web services. Dynamism is directly related to the changes in the repositories (services registered or unregistered) and at service level (annotation changes). Thus, users, software clients or workflow based approaches lack enough relevant information to decide when they should review or re-execute a Web service or workflow to get updated or improved results. The dynamism of the repository could be a measure for workflow developers to re-check service availability and annotation changes in the services of interest to them. This paper presents a review on the most well-known Web service repositories in the life sciences including an analysis of their dynamism. Freshness is introduced in this paper, and has been used as the measure for the dynamism of these repositories. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  7. Investigations of possibilities to dispose of spent nuclear fuel in Lithuania: a model case. Volume 2, Concept of Repository in Crystalline Rocks

    International Nuclear Information System (INIS)

    Motiejunas, S.; Poskas, P.

    2005-01-01

    The aim is to present the generic repository concept in crystalline rocks in Lithuania and cost assessment of the disposal of spent nuclear fuel and long-lived intermediate level waste in this repository. Due to limited budget of this project the repository concept development for Lithuania was based mostly on the experience of foreign countries. In this Volume a review of the existing information on disposal concept in crystalline rocks from various countries is presented. Described repository concept for crystalline rocks in Lithuania covers repository layout, backfill, canister, construction materials and auxiliary buildings. Costs calculations for disposal of spent nuclear fuel and long-lived intermediate-level wastes from Ignalina NPP are presented too. Thermal, criticality and other important disposal evaluations for RBMK-1500 spent nuclear fuel emplaced in copper canister were performed and described

  8. Natural Elemental Concentrations and Fluxes: Their Use as Indicators of Repository Safety

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Bill; Lind, Andy; Savage, Dave; Maul, Philip; Robinson, Peter [EnvirosQuantisci, Melton Mowbray (United Kingdom)

    2002-03-01

    individual processes, such as groundwater discharge, river flow and erosion at specific locations. The approach can also be of value at the generic level of repository development, before site characterisation programmes have been undertaken. They could be used, for example, as a component in comparative evaluations of alternative generic disposal concepts. The objective at the generic level would be to define typical or average natural elemental concentrations and fluxes in geological systems representative of the environments which might host a repository, and to compare these with the outputs from the associated generic PAs. To facilitate the use of the natural safety indicators methodology at the generic level, this study has undertaken to bring together and to compile much of the required information. This information has been used to quantify average elemental mass fluxes at the global scale for a range of processes, including groundwater discharge, erosion and sediment transport. The point of these calculations is that they provide a baseline against which site or geological environment specific natural fluxes, from anywhere in the world, can be compared on an equal basis to evaluate if they are higher or lower than the global average and, thus, are useful for providing a broad natural context for predicted repository releases. In separate calculations, elemental mass fluxes were quantified for a number of reference environments which are chosen to be representative of the types of sites and geological systems which may host a deep repository. The reference environments were an inland pluton, basement under sedimentary cover and a sedimentary basin. The fluxes for these environments were calculated for systems with spatial scales of a few hundred square kilometres and, as such, approximate closely to the repository systems modelled in PAs because a reference environment represents the same system, with the same rock, groundwater and surface conditions as those

  9. IAEA safeguards for geological repositories

    International Nuclear Information System (INIS)

    Moran, B.W.

    2005-01-01

    In September. 1988, the IAEA held its first formal meeting on the safeguards requirements for the final disposal of spent fuel and nuclear material-bearing waste. The consensus recommendation of the 43 participants from 18 countries at this Advisory Group Meeting was that safeguards should not terminate of spent fuel even after emplacement in, and closure of, a geologic repository.' As a result of this recommendation, the IAEA initiated a series of consultants' meetings and the SAGOR Programme (Programme for the Development of Safeguards for the Final Disposal of Spent Fuel in Geologic Repositories) to develop an approach that would permit IAEA safeguards to verify the non-diversion of spent fuel from a geologic repository. At the end of this process, in December 1997, a second Advisory Group Meeting, endorsed the generic safeguards approach developed by the SAGOR Programme. Using the SAGOR Programme results and consultants' meeting recommendations, the IAEA Department of Safeguards issued a safeguards policy paper stating the requirements for IAEA safeguards at geologic repositories. Following approval of the safeguards policy and the generic safeguards approach, the Geologic Repository Safeguards Experts Group was established to make recommendations on implementing the safeguards approach. This experts' group is currently making recommendations to the IAEA regarding the safeguards activities to be conducted with respect to Finland's repository programme. (author)

  10. Integrated Parasite Management for Livestock - Alternative control methods

    Directory of Open Access Journals (Sweden)

    Souvik Paul1

    Full Text Available Internal parasites are considered by some to be one of the most economically important constraints in raising livestock. The growing concern about the resistance of internal parasites to all classes of dewormers has caused people to look for alternatives. As dewormers lose their effectiveness, the livestock community fears increasing economic losses from worms. There is no one thing that can be given or done to replace chemical dewormers. It will take a combination of extremely good management techniques and possibly some alternative therapies. It is not wise to think that one can just stop deworming animals with chemical dewormers. It is something one will need to change gradually, observing and testing animals and soil, in order to monitor the progress. Alternative parasite control is an area that is receiving a lot of interest and attention. Programs and research will continue in the pursuit of parasite control, using alternative and more management-intensive methods. [Veterinary World 2010; 3(9.000: 431-435

  11. One-shot service searches: Preprint repositories at a mouseclick

    Energy Technology Data Exchange (ETDEWEB)

    Canessa, E [International Centre for Theoretical Physics, Trieste (Italy); Pastore, G [Trieste Univ., Trieste (Italy). Dipt. di Fisica

    1996-09-01

    In this article we introduce the ICTP-International Centre for Theoretical Physics`s prototype for a ``One-Shot World-Wide Preprints Search`` on the Web. This is a new centralized interface for a global search throughout the most popular scientific preprint repositories. Herein, we briefly discuss our experience with the implementation of this service and propose it as a possible alternative solution to the problem of getting access to the information without being either overloaded with lots of new documents or not being informed at all. (author). 13 refs, 3 figs.

  12. One-shot service searches: Preprint repositories at a mouseclick

    International Nuclear Information System (INIS)

    Canessa, E.; Pastore, G.

    1996-09-01

    In this article we introduce the ICTP-International Centre for Theoretical Physics's prototype for a ''One-Shot World-Wide Preprints Search'' on the Web. This is a new centralized interface for a global search throughout the most popular scientific preprint repositories. Herein, we briefly discuss our experience with the implementation of this service and propose it as a possible alternative solution to the problem of getting access to the information without being either overloaded with lots of new documents or not being informed at all. (author). 13 refs, 3 figs

  13. Refinancing of the search for a repository and of the repository for heat generating radioactive waste. Pt. 1

    International Nuclear Information System (INIS)

    Moench, Christoph

    2013-01-01

    The final disposal of radioactive waste is a state task that is assigned to the Federal Government pursuant to section 9a (3) sentence 1 of the Atomic Energy Act (AtG). Since the early 1970's, the Federal Government has been actively searching for and exploring final disposal sites for radioactive waste. In a proceeding accompanied by the intensive participation of technical experts and the public, the Gorleben salt dome (Salzstock) has emerged as a presumably suitable disposal site from a mining standpoint (eignungshoeffig) according to the current status of the exploration. The cost of these exploratory measures - and the subsequent construction - will be financed by the waste producers, in particular the utility companies, by means of advance payments on their contributions. Part I of this article will evaluate the selection and exploration of the Gorleben salt dome to date and examine the provisions on the pre-financing burden from the point of view of constitutional law. Constitutional objections can also be raised against the regulation in section 21b (4) AtG that was introduced in 1998, which excludes a refunding of the pre-financing contributions even if the repository is never erected or operated. Part II of this article, which will appear in the next issue, will take up the question of whether a search for an alternative repository site, as the Federal Ministry for the Environment (BMU) envisions in the working draft of an 'Act on the search for and selection of a site for a repository for heat generating radioactive waste' (Gesetz zur Suche und Auswahl eines Standortes fuer ein Endlager fuer waermeentwickelnde radioaktive Abfaelle), is likewise to be refinanced as a contribution by the parties obliged to make advance payments. (orig.)

  14. Field instrumentation and testing needs for a high level waste repository

    International Nuclear Information System (INIS)

    Marti, J.; Maini, T.

    1981-03-01

    A review has been conducted of the testing and measurement needs posed by a deep geologic High Level Waste (HLW) repository in crystalline or argillaceous rocks. Siting, design, construction, operation and decommissioning of the repository have been covered, together with the planning of a Test and Demonstration Facility. Instruments and methods available have been critically assessed in their ability to fulfil the aforementioned testing and monitoring programmes. Special attention has been paid to the relation of measurements to the data needs and to the tests likely to generate such data. This assessment has concentrated on measurements of absolute rock stresses, monitoring of changes in rock stress, evaluation of the rock mass deformability, measurement of relative displacements and determination of the hydrogeologic parameters of the rock mass. Other measurements have been studied with a lesser degree of attention. The overall conclusion is that, from the instrumentation and testing points of view, present plans for a test and demonstration facility in the early nineties and a repository soon after 2000 are indeed feasible. Specific conclusions on the state-of-the-art and development needs are presented in the report. (author)

  15. Gas generation in repositories

    International Nuclear Information System (INIS)

    Biddle, P.; Rees, J.H.; McGahan, D.; Rushbrook, P.E.

    1987-09-01

    The nature and quantities of gases likely to be produced by various processes in repositories for low level and intermediate level radioactive wastes are examined in this preliminary study. Many simplifying assumptions are made where published or experimental data is unavailable. The corrosion of the canisters and metallic components in wastes is likely to be the major gas production process in both types of repository. A significant contribution from microbiological activity is expected to occur in low level repositories, predominantly where no cement grouting of the cans has been carried out. A number of areas for further research, required before a more comprehensive study could be carried out, have been identified. (author)

  16. Faulting in the Yucca Mountain region: Critical review and analyses of tectonic data from the central Basin and Range

    International Nuclear Information System (INIS)

    Ferrill, D.A.; Stirewalt, G.L.; Henderson, D.B.; Stamatakos, J.; Morris, A.P.; Spivey, K.H.; Wernicke, B.P.

    1996-03-01

    Yucca Mountain, Nevada, has been proposed as the potential site for a high-level waste (HLW) repository. The tectonic setting of Yucca Mountain presents several potential hazards for a proposed repository, such as potential for earthquake seismicity, fault disruption, basaltic volcanism, magma channeling along pre-existing faults, and faults and fractures that may serve as barriers or conduits for groundwater flow. Characterization of geologic structures and tectonic processes will be necessary to assess compliance with regulatory requirements for the proposed high level waste repository. In this report, we specifically investigate fault slip, seismicity, contemporary stain, and fault-slip potential in the Yucca Mountain region with regard to Key Technical Uncertainties outlined in the License Application Review Plan (Sections 3.2.1.5 through 3.2.1.9 and 3.2.2.8). These investigations center on (i) alternative methods of determining the slip history of the Bare Mountain Fault, (ii) cluster analysis of historic earthquakes, (iii) crustal strain determinations from Global Positioning System measurements, and (iv) three-dimensional slip-tendency analysis. The goal of this work is to assess uncertainties associated with neotectonic data sets critical to the Nuclear Regulatory Commission and the Center for Nuclear Waste Regulatory Analyses' ability to provide prelicensing guidance and perform license application review with respect to the proposed HLW repository at Yucca Mountain

  17. Adaptive Critic Nonlinear Robust Control: A Survey.

    Science.gov (United States)

    Wang, Ding; He, Haibo; Liu, Derong

    2017-10-01

    Adaptive dynamic programming (ADP) and reinforcement learning are quite relevant to each other when performing intelligent optimization. They are both regarded as promising methods involving important components of evaluation and improvement, at the background of information technology, such as artificial intelligence, big data, and deep learning. Although great progresses have been achieved and surveyed when addressing nonlinear optimal control problems, the research on robustness of ADP-based control strategies under uncertain environment has not been fully summarized. Hence, this survey reviews the recent main results of adaptive-critic-based robust control design of continuous-time nonlinear systems. The ADP-based nonlinear optimal regulation is reviewed, followed by robust stabilization of nonlinear systems with matched uncertainties, guaranteed cost control design of unmatched plants, and decentralized stabilization of interconnected systems. Additionally, further comprehensive discussions are presented, including event-based robust control design, improvement of the critic learning rule, nonlinear H ∞ control design, and several notes on future perspectives. By applying the ADP-based optimal and robust control methods to a practical power system and an overhead crane plant, two typical examples are provided to verify the effectiveness of theoretical results. Overall, this survey is beneficial to promote the development of adaptive critic control methods with robustness guarantee and the construction of higher level intelligent systems.

  18. Nuclear waste repository siting

    International Nuclear Information System (INIS)

    Soloman, B.D.; Cameron, D.M.

    1987-01-01

    This paper discusses the geopolitics of nuclear waste disposal in the USA. Constitutional choice and social equity perspectives are used to argue for a more open and just repository siting program. The authors assert that every potential repository site inevitably contains geologic, environmental or other imperfections and that the political process is the correct one for determining sites selected

  19. Granite-repository - geochemical environment

    International Nuclear Information System (INIS)

    1979-04-01

    Some geochemical data of importance for a radioactive waste repository in hard rock are reviewed. The ground water composition at depth is assessed. The ground water chemistry in the vicinity of uranium ores is discussed. The redox system in Swedish bedrock is described. Influences of extreme climatic changes and of repository mining and construction are also evaluated

  20. High-level waste repository-induced effects

    Energy Technology Data Exchange (ETDEWEB)

    Leupin, O.X.; Marschall, P.; Johnson, L.; Cloet, V.; Schneider, J. [National Cooperative for the Disposal of Radioactive Waste (NAGRA), Wettingen (Switzerland); Smith, P. [Safety Assessment Management Ltd, Henley-On-Thames, Oxfordshire (United Kingdom); Savage, D. [Savage Earth Associates Ltd, Bournemouth, Dorset (United Kingdom); Senger, R. [Intera Inc., Ennetbaden (Switzerland)

    2016-10-15

    This status report aims at describing and assessing the interactions of the radioactive waste emplaced in a high-level waste (HLW) repository with the engineered materials and the Opalinus Clay host rock. The Opalinus Clay has a thickness of about 100 m in the proposed siting regions. Among other things the results are used to steer the RD and D programme of NAGRA. The repository-induced effects considered in this report are of the following broad types: - Thermal effects: i.e. effects on the host rock and engineered barriers arising principally from the heat generated by the waste. - Rock-mechanical effects: i.e. effects arising from the mechanical disturbance to the rock caused by the excavation of the emplacement rooms and other underground structures. - Hydraulic and gas-related effects: i.e. the effects of repository resaturation and of gas generation, e.g. due to the corrosion of metals within the repository, on the host rock and engineered barriers. - Chemical effects: i.e. chemical interactions between the waste, the engineered materials and the host rock, with a focus on chemical effects of the waste and engineered materials on the host rock. The assessment of the repository-induced effects shows that detrimental chemical and mechanical impacts are largely confined to the rock immediately adjacent to the excavations, thermal impacts are controllable by limiting the heat load and gas effects are limited by ensuring acceptably low gas production rates and by the natural tendency of the gas to escape along the excavations and the excavation damaged zone (EDZ) rather than through the undisturbed rock. Specific measures that are part of the current reference design are discussed in relation to their significance with respect to repository-induced effects. The SF/HLW emplacement rooms (emplacement drifts) are designed, constructed, operated and finally backfilled in such a way that formation of excavation damaged zones is limited. Specifically this is achieved

  1. High-level waste repository-induced effects

    International Nuclear Information System (INIS)

    Leupin, O.X.; Marschall, P.; Johnson, L.; Cloet, V.; Schneider, J.; Smith, P.; Savage, D.; Senger, R.

    2016-10-01

    This status report aims at describing and assessing the interactions of the radioactive waste emplaced in a high-level waste (HLW) repository with the engineered materials and the Opalinus Clay host rock. The Opalinus Clay has a thickness of about 100 m in the proposed siting regions. Among other things the results are used to steer the RD and D programme of NAGRA. The repository-induced effects considered in this report are of the following broad types: - Thermal effects: i.e. effects on the host rock and engineered barriers arising principally from the heat generated by the waste. - Rock-mechanical effects: i.e. effects arising from the mechanical disturbance to the rock caused by the excavation of the emplacement rooms and other underground structures. - Hydraulic and gas-related effects: i.e. the effects of repository resaturation and of gas generation, e.g. due to the corrosion of metals within the repository, on the host rock and engineered barriers. - Chemical effects: i.e. chemical interactions between the waste, the engineered materials and the host rock, with a focus on chemical effects of the waste and engineered materials on the host rock. The assessment of the repository-induced effects shows that detrimental chemical and mechanical impacts are largely confined to the rock immediately adjacent to the excavations, thermal impacts are controllable by limiting the heat load and gas effects are limited by ensuring acceptably low gas production rates and by the natural tendency of the gas to escape along the excavations and the excavation damaged zone (EDZ) rather than through the undisturbed rock. Specific measures that are part of the current reference design are discussed in relation to their significance with respect to repository-induced effects. The SF/HLW emplacement rooms (emplacement drifts) are designed, constructed, operated and finally backfilled in such a way that formation of excavation damaged zones is limited. Specifically this is achieved

  2. Workshop: Creating Your Institutional Research Repository

    KAUST Repository

    Grenz, Daryl M.

    2016-11-08

    In 2002, the Scholarly Publishing and Academic Resources Coalition (SPARC) proposed the concept of an institutional repository to simultaneously disrupt and enhance the state of scholarly communications in the academic world. Thirteen years later, thousands of universities and other institutions have answered this call, but many more have not due to gaps in budgets, awareness and, most of all, practical guidance on creating an institutional repository. This workshop provides you with an essential primer on what it takes to establish a fully-functioning institutional repository. Every aspect of the process will be covered, including policies, procedures, staffing guidelines, workflows and repository technologies.

  3. Deep repository for long-lived low- and intermediate-level waste. Preliminary safety assessment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-11-01

    A preliminary safety assessment has been performed of a deep repository for long-lived low- and intermediate-level waste, SFL 3-5. The purpose of the study is to investigate the capacity of the facility to act as a barrier to the release of radionuclides and toxic pollutants, and to shed light on the importance of the location of the repository site. A safety assessment (SR 97) of a deep repository for spent fuel has been carried out at the same time. In SR 97, three hypothetical repository sites have been selected for study. These sites exhibit fairly different conditions in terms of hydrogeology, hydrochemistry and ecosystems. To make use of information and data from the SR 97 study, we have assumed that SFL 3-5 is co-sited with the deep repository for spent fuel. A conceivable alternative is to site SFL 3-5 as a completely separate repository. The focus of the SFL 3-5 study is a quantitative analysis of the environmental impact for a reference scenario, while other scenarios are discussed and analyzed in more general terms. Migration in the repository's near- and far-field has been taken into account in the reference scenario. Environmental impact on the three sites has also been calculated. The calculations are based on an updated forecast of the waste to be disposed of in SFL 3-5. The forecast includes radionuclide content, toxic metals and other substances that have a bearing on a safety assessment. The safety assessment shows how important the site is for safety. Two factors stand out as being particularly important: the water flow at the depth in the rock where the repository is built, and the ecosystem in the areas on the ground surface where releases may take place in the future. Another conclusion is that radionuclides that are highly mobile and long-lived, such as {sup 36}Cl and {sup 93}Mo , are important to take into consideration. Their being long-lived means that barriers and the ecosystems must be regarded with a very long time horizon.

  4. Alternative Splicing Control of Abiotic Stress Responses.

    Science.gov (United States)

    Laloum, Tom; Martín, Guiomar; Duque, Paula

    2018-02-01

    Alternative splicing, which generates multiple transcripts from the same gene, is an important modulator of gene expression that can increase proteome diversity and regulate mRNA levels. In plants, this post-transcriptional mechanism is markedly induced in response to environmental stress, and recent studies have identified alternative splicing events that allow rapid adjustment of the abundance and function of key stress-response components. In agreement, plant mutants defective in splicing factors are severely impaired in their response to abiotic stress. Notably, mounting evidence indicates that alternative splicing regulates stress responses largely by targeting the abscisic acid (ABA) pathway. We review here current understanding of post-transcriptional control of plant stress tolerance via alternative splicing and discuss research challenges for the near future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Criticality Model

    International Nuclear Information System (INIS)

    Alsaed, A.

    2004-01-01

    The ''Disposal Criticality Analysis Methodology Topical Report'' (YMP 2003) presents the methodology for evaluating potential criticality situations in the monitored geologic repository. As stated in the referenced Topical Report, the detailed methodology for performing the disposal criticality analyses will be documented in model reports. Many of the models developed in support of the Topical Report differ from the definition of models as given in the Office of Civilian Radioactive Waste Management procedure AP-SIII.10Q, ''Models'', in that they are procedural, rather than mathematical. These model reports document the detailed methodology necessary to implement the approach presented in the Disposal Criticality Analysis Methodology Topical Report and provide calculations utilizing the methodology. Thus, the governing procedure for this type of report is AP-3.12Q, ''Design Calculations and Analyses''. The ''Criticality Model'' is of this latter type, providing a process evaluating the criticality potential of in-package and external configurations. The purpose of this analysis is to layout the process for calculating the criticality potential for various in-package and external configurations and to calculate lower-bound tolerance limit (LBTL) values and determine range of applicability (ROA) parameters. The LBTL calculations and the ROA determinations are performed using selected benchmark experiments that are applicable to various waste forms and various in-package and external configurations. The waste forms considered in this calculation are pressurized water reactor (PWR), boiling water reactor (BWR), Fast Flux Test Facility (FFTF), Training Research Isotope General Atomic (TRIGA), Enrico Fermi, Shippingport pressurized water reactor, Shippingport light water breeder reactor (LWBR), N-Reactor, Melt and Dilute, and Fort Saint Vrain Reactor spent nuclear fuel (SNF). The scope of this analysis is to document the criticality computational method. The criticality

  6. Office of Geologic Repositories program baseline procedures notebook (OGR/B-1)

    International Nuclear Information System (INIS)

    1986-06-01

    Baseline management is typically applied to aid in the internal control of a program by providing consistent programmatic direction, control, and surveillance to an evolving system development. This fundamental concept of internal program control involves the establishment of a baseline to serve as a point of departure for consistent technical program coordination and to control subsequent changes from that baseline. The existence of a program-authorized baseline ensures that all participants are working to the same ground rules. Baseline management also ensures that, once the baseline is defined, changes are assessed and approved by a process which ensures adequate consideration of overall program impact. Baseline management also includes the consideration of examptions from the baseline. The process of baseline management continues through all the phases of an evolving system development program. As the Program proceeds, there will be a progressive increase in the data contained in the baseline documentation. Baseline management has been selected as a management technique to aid in the internal control of the Office of Geologic Repositories (OGR) program. Specifically, an OGR Program Baseline, including technical and programmatic requirements, is used for program control of the four Mined Geologic Disposal System field projects, i.e., Basalt Waste Isolation Project, Nevada Nuclear Waste Storage Investigation, Salt Repository Project and Crystalline Repository Project. This OGR Program Baseline Procedures Notebook provides a description of the baseline mwanagement concept, establishes the OGR Program baseline itself, and provides procedures to be followed for controlling changes to that baseline. The notebook has a controlled distribution and will be updated as required

  7. Thermal analyses of spent nuclear fuel repository

    International Nuclear Information System (INIS)

    Ikonen, K.

    2003-06-01

    This report contains the temperature dimensioning of the KBS-3V type 1- or 2-panel repository based on the rock properties measured from the Olkiluoto investigations. The report describes first the development of a calculation methodology for the thermal analysis of a repository for nuclear fuel. The disposed canisters produce residual heat due to decay (or disintegration) of radioactive products. The decay heat is conducted to surrounding rock mass. The methods were applied to determine the effect of different parameters on the highest canister temperature and to support the planning, dimensioning and operation of the repository. The thermal diffusivity of the rock is low and the heat released from the canisters is spread into the surrounding rock volume quite slowly causing thermal gradient in the rock close to canisters and the canister temperature is increased remarkably. The maximum temperature on the canister surface is limited to the design temperature of +100 deg C. However, due to uncertainties in thermal analysis parameters (like scattering in rock conductivity) the allowable calculated maximum canister temperature is set to 90 deg C causing a safety margin of 10 deg C. The allowable temperature is controlled by the spacing between adjacent canisters, adjacent tunnels and the distance between separate panels of the repository and the pre-cooling time affecting power of the canisters. Because of the fact that the disposal operation takes several decades, the moment of disposal of an individual canister in addition to the location has an influence on the maximum temperature in the canister. Also, a second disposal panel in the repository has a thermal interaction with the other panel. This interaction is expressed after a few decades at the strongest. It became apparent that the temperature of canister surfaces can be determined by analytic line heat source model much more efficiently than by numerical analysis, if the analytic model is first verified and

  8. Secured web-based video repository for multicenter studies.

    Science.gov (United States)

    Yan, Ling; Hicks, Matt; Winslow, Korey; Comella, Cynthia; Ludlow, Christy; Jinnah, H A; Rosen, Ami R; Wright, Laura; Galpern, Wendy R; Perlmutter, Joel S

    2015-04-01

    We developed a novel secured web-based dystonia video repository for the Dystonia Coalition, part of the Rare Disease Clinical Research network funded by the Office of Rare Diseases Research and the National Institute of Neurological Disorders and Stroke. A critical component of phenotypic data collection for all projects of the Dystonia Coalition includes a standardized video of each participant. We now describe our method for collecting, serving and securing these videos that is widely applicable to other studies. Each recruiting site uploads standardized videos to a centralized secured server for processing to permit website posting. The streaming technology used to view the videos from the website does not allow downloading of video files. With appropriate institutional review board approval and agreement with the hosting institution, users can search and view selected videos on the website using customizable, permissions-based access that maintains security yet facilitates research and quality control. This approach provides a convenient platform for researchers across institutions to evaluate and analyze shared video data. We have applied this methodology for quality control, confirmation of diagnoses, validation of rating scales, and implementation of new research projects. We believe our system can be a model for similar projects that require access to common video resources. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Conclusion of the Preliminary Safety report for the LILW Repository on Trgovska Gora

    International Nuclear Information System (INIS)

    Lokner, V.; Levanat, I.; Schaller, A.; Kucar-Dragicevic, S.; Cerskov Klika, M.; Subasic, D.

    2002-01-01

    For more than a decade, APO d.o.o. has been engaged in preparations which might lead to establishment of a radioactive waste repository on Trgovska Gora, suitable for disposal of low and intermediate level waste (LILW) from the nuclear power plant Krsko. A recent product of theses activities is the preliminary safety assessment report (PSAR) for the proposed repository. In addition to an extensive overview of the repository project status, this preliminary SAR describes how the safety assessment methodology is used to demonstrate that a LILW facility will comply with radiological protection and safety requirements after the repository closure. LILW repository is designed to isolate waste from the environment for a couple hundred years in a reasonably efficient manner. It is generally not practicable to grant full waste containment throughout that period, because it suffices to demonstrate that radionuclide release and migration will remain below acceptable levels, which is achieved through safety assessment scenarios, modeling and calculations. However, with very limited repository specific data, safety assessment can only produce a conservative estimate of the upper bounds of potential exposures the repository could inflict. This PSAR arrives at such estimates in two different ways: (a) by simple bounding calculations and (b) through more sophisticated modeling and application of dedicated computer codes, but with similar conservative assumptions. Both approaches conservatively estimate that the highest potential dose to a nearby resident cannot significantly exceed the dose constraint of 0.2 mSv per year. Only in case of inadvertent intrusion into the near-surface disposal vault, much higher doses might be inflicted immediately after the planned institutional control of 250 years expires, but that can be prevented by a longer control period. Despite the preliminary and bounding style of the calculations, the PSAR has identified most important assumptions and

  10. Safeguards for geological repositories

    International Nuclear Information System (INIS)

    Fattah, A.

    2000-01-01

    Direct disposal of spent nuclear fuel in geological repositories is a recognised option for closing nuclear fuel cycles. Geological repositories are at present in stages of development in a number of countries and are expected to be built and operated early next century. A State usually has an obligation to safely store any nuclear material, which is considered unsuitable to re-enter the nuclear fuel cycle, isolated from the biosphere. In conjunction with this, physical protection has to be accounted for to prevent inadvertent access to such material. In addition to these two criteria - which are fully under the State's jurisdiction - a third criterion reflecting international non-proliferation commitments needs to be addressed. Under comprehensive safeguards agreements a State concedes verification of nuclear material for safeguards purposes to the IAEA. The Agency can thus provide assurance to the international community that such nuclear material has been used for peaceful purposes only as declared by the State. It must be emphasised that all three criteria mentioned constitute a 'unit'. None can be sacrificed for the sake of the other, but compromises may have to be sought in order to make their combination as effective as possible. Based on comprehensive safeguards agreements signed and ratified by the State, safeguards can be terminated only when the material has been consumed or diluted in such a way that it can no longer be utilised for any nuclear activities or has become practicably irrecoverable. As such safeguards for nuclear material in geological repositories have to be continued even after the repository has been back-filled and sealed. The effective application of safeguards must assure continuity-of-knowledge that the nuclear material in the repository has not been diverted for an unknown purpose. The nuclear material disposed in a geological repository may eventually have a higher and long term proliferation risk because the inventory is

  11. The Proposed Yucca Mountain Repository From A Corrosion Perspective

    International Nuclear Information System (INIS)

    J.H. Payer

    2005-01-01

    Corrosion is a primary determinant of waste package performance at the proposed Yucca Mountain Repository and will control the delay time for radionuclide transport from the waste package. Corrosion is the most probable and most likely degradation process that will determine when packages will be penetrated and the shape, size, and distribution of those penetrations. The general issues in corrosion science, materials science and electrochemistry are well defined, and the knowledge base is substantial for understanding corrosion processes. In this paper, the Yucca Mountain Repository is viewed from a corrosion perspective. A major component of the long-term strategy for safe disposal of nuclear waste at the Yucca Mountain Repository is first to completely isolate the radionuclides in the waste packages for long times and to greatly retard the egress and transport of radionuclides from penetrated packages. Therefore, long-lived waste packages are important. The corrosion resistance of the waste package outer canister is reviewed, and a framework for the analysis of localized corrosion processes is presented. An overview is presented of the Materials Performance targeted thrust of the U.S. Department of Energy/Office of Civilian Radioactive Waste Management's Office of Science and Technology and International. The thrust program strives for increased scientific understanding, enhanced process models and advanced technologies for corrosion control

  12. Modelling saline intrusion for repository performance assessment

    International Nuclear Information System (INIS)

    Jackson, C.P.

    1989-04-01

    UK Nirex Ltd are currently considering the possibility of disposal of radioactive waste by burial in deep underground repositories. The natural pathway for radionuclides from such a repository to return to Man's immediate environment (the biosphere) is via groundwater. Thus analyses of the groundwater flow in the neighbourhood of a possible repository, and consequent radionuclide transport form an important part of a performance assessment for a repository. Some of the areas in the UK that might be considered as possible locations for a repository are near the coast. If a repository is located in a coastal region seawater may intrude into the groundwater flow system. As seawater is denser than fresh water buoyancy forces acting on the intruding saline water may have significant effects on the groundwater flow system, and consequently on the time for radionuclides to return to the biosphere. Further, the chemistry of the repository near-field may be strongly influenced by the salinity of the groundwater. It is therefore important for Nirex to have a capability for reliably modelling saline intrusion to an appropriate degree of accuracy in order to make performance assessments for a repository in a coastal region. This report describes work undertaken in the Nirex Research programme to provide such a capability. (author)

  13. Analisis Konten dan Kebijakan Akses Institutional Repository

    Directory of Open Access Journals (Sweden)

    Amirul Ulum

    2016-07-01

    Abstract; Institutional repository has become a major concern of higher education in Indonesia. The number of institutional respository was increased, one of the reason is the ranking web of repositories has been conducted by the Cybermetrics Lab in 2008. At that time, many institutions started to build institutional repository in order to manage the scientific work and also trying to reach the better ranks. Meanwhile, it is an achievement of institution performance which can be promote and increase visibility for the institution. University of Surabaya has also developed the institutional repository and managed by the library. The aims of this study is to analyze the content availability and access policies defined by the University of Surabaya repository  providing services to the academic community and external users. The method used in this study by using observations of the institutional repository University of Surabaya with a literature review to clarify the analysis of the content and access policies. The results of this study indicate that the library's role is has the authority to manage the scientific work of academic community can be done through the institutional repository. However there is still need for library to be proactive to communicate regulations on mandatory deposit of scientific work and create intensive promotion of the institutional repository.

  14. Production, consumption and transport of gases in deep geological repositories according to the Swiss disposal concept

    International Nuclear Information System (INIS)

    Diomidis, N; Cloet, V.; Leupin, O.X.; Marschall, P.; Poller, A.; Stein, M.

    2016-12-01

    consumption of gas. The evolution of the gas generation rate and of the cumulative gas volume during the time frame for safety assessment is then calculated. The outcome is used as input to the modelling of gas transport and the resulting build-up of gas pressure and gas induced water flow, which are used as safety function indicators. Uncertainties and options are combined into specific assessment cases, which are used to specify the expected ranges of safety-relevant parameters, to highlight the potential effects of mitigating measures aiming to decrease the amount of generated gas, and to identify areas where further research could provide the most benefit. The main outcome of the performance assessment is that for pessimistic base cases, and even for the upper bounding cases, gas production in the HLW and L/ILW repositories does not compromise the post-closure safety functions of the host rock and the engineered barriers. In all the cases explored there is a safety margin with regards to the defined assessment criteria. Moreover, there are several design options available that can further mitigate the consequences of gas production in the repositories if necessary. In both repository types, gas production is dominated by hydrogen resulting mainly from the corrosion of carbon steel. As a result, alternative emplacement and building technologies, alternative disposal canister materials, or treatment of metallic waste by melting could reduce the amount of repository-generated gas during the period for safety assessment. The build-up of gas overpressure and resulting pore water displacement could also be mitigated by thriving gas-consuming microorganisms or by tailoring the engineered gas transport system. (authors)

  15. Production, consumption and transport of gases in deep geological repositories according to the Swiss disposal concept

    Energy Technology Data Exchange (ETDEWEB)

    Diomidis, N; Cloet, V.; Leupin, O.X.; Marschall, P.; Poller, A.; Stein, M.

    2016-12-15

    consumption of gas. The evolution of the gas generation rate and of the cumulative gas volume during the time frame for safety assessment is then calculated. The outcome is used as input to the modelling of gas transport and the resulting build-up of gas pressure and gas induced water flow, which are used as safety function indicators. Uncertainties and options are combined into specific assessment cases, which are used to specify the expected ranges of safety-relevant parameters, to highlight the potential effects of mitigating measures aiming to decrease the amount of generated gas, and to identify areas where further research could provide the most benefit. The main outcome of the performance assessment is that for pessimistic base cases, and even for the upper bounding cases, gas production in the HLW and L/ILW repositories does not compromise the post-closure safety functions of the host rock and the engineered barriers. In all the cases explored there is a safety margin with regards to the defined assessment criteria. Moreover, there are several design options available that can further mitigate the consequences of gas production in the repositories if necessary. In both repository types, gas production is dominated by hydrogen resulting mainly from the corrosion of carbon steel. As a result, alternative emplacement and building technologies, alternative disposal canister materials, or treatment of metallic waste by melting could reduce the amount of repository-generated gas during the period for safety assessment. The build-up of gas overpressure and resulting pore water displacement could also be mitigated by thriving gas-consuming microorganisms or by tailoring the engineered gas transport system. (authors)

  16. Critical and Alternative Directions in Applied Linguistics

    Science.gov (United States)

    Pennycook, Alastair

    2010-01-01

    Critical directions in applied linguistics can be understood in various ways. The term "critical" as it has been used in "critical applied linguistics," "critical discourse analysis," "critical literacy" and so forth, is now embedded as part of applied linguistic work, adding an overt focus on questions of power and inequality to discourse…

  17. Process model repositories and PNML

    NARCIS (Netherlands)

    Hee, van K.M.; Post, R.D.J.; Somers, L.J.A.M.; Werf, van der J.M.E.M.; Kindler, E.

    2004-01-01

    Bringing system and process models together in repositories facilitates the interchange of model information between modelling tools, and allows the combination and interlinking of complementary models. Petriweb is a web application for managing such repositories. It supports hierarchical process

  18. A Critical Examination of the Process of Modifying the Curriculum of Alternative Secondary Educational Programs

    Science.gov (United States)

    Ross, Michael

    2014-01-01

    This study, "A Critical Examination of the Process of Modifying the Curriculum of Alternative Secondary Educational Programs," was done with the use of action research to study (a) whether students currently participating in a continuation school believe their educational and career needs are presently being met; (b) the types of career…

  19. Radioactive waste repository study

    International Nuclear Information System (INIS)

    1978-11-01

    This is the second part of a report of a preliminary study for AECL. It considers the requirements for an underground waste repository for the disposal of wastes produced by the Canadian Nuclear Fuel Program. The following topics are discussed with reference to the repository: 1) geotechnical assessment, 2) hydrogeology and waste containment, 3) thermal loading and 4) rock mechanics. (author)

  20. Rail Access to Yucca Mountain: Critical Issues

    International Nuclear Information System (INIS)

    Halstead, R. J.; Dilger, F.; Moore, R. C.

    2003-01-01

    The proposed Yucca Mountain repository site currently lacks rail access. The nearest mainline railroad is almost 100 miles away. Absence of rail access could result in many thousands of truck shipments of spent nuclear fuel and high-level radioactive waste. Direct rail access to the repository could significantly reduce the number of truck shipments and total shipments. The U.S. Department of Energy (DOE) identified five potential rail access corridors, ranging in length from 98 miles to 323 miles, in the Final Environmental Impact Statement (FEIS) for Yucca Mountain. The FEIS also considers an alternative to rail spur construction, heavy-haul truck (HHT) delivery of rail casks from one of three potential intermodal transfer stations. The authors examine the feasibility and cost of the five rail corridors, and DOE's alternative proposal for HHT transport. The authors also address the potential for rail shipments through the Las Vegas metropolitan area

  1. The Alternate Technology Program for Aluminum Research Reactor Spent Fuel

    International Nuclear Information System (INIS)

    Barlow, M.W.

    1998-01-01

    This paper describes the program for disposition of aluminum-based RRSNF, including the requirements for road-ready dry storage and repository disposal and the criteria to be considered in selecting among the alternative technologies

  2. Citing and Reading Behaviors of High-Energy Physics or How a Community Stopped Worrying about Journals and Learned to Love Repositories

    International Nuclear Information System (INIS)

    Gentil-Beccot, Anne; Mele, Salvatore; Brooks, Travis C.

    2009-01-01

    Contemporary scholarly discourse follows many alternative routes in addition to the three-century old tradition of publication in peer-reviewed journals. The field of High-Energy Physics (HEP) has explored alternative communication strategies for decades, initially via the mass mailing of paper copies of preliminary manuscripts, then via the inception of the first online repositories and digital libraries. This field is uniquely placed to answer recurrent questions raised by the current trends in scholarly communication: is there an advantage for scientists to make their work available through repositories, often in preliminary form? Is there an advantage to publishing in Open Access journals? Do scientists still read journals or do they use digital repositories? The analysis of citation data demonstrates that free and immediate online dissemination of preprints creates an immense citation advantage in HEP, whereas publication in Open Access journals presents no discernible advantage. In addition, the analysis of clickstreams in the leading digital library of the field shows that HEP scientists seldom read journals, preferring preprints instead.

  3. Citing and Reading Behaviors of High-Energy Physics or How a Community Stopped Worrying about Journals and Learned to Love Repositories

    Energy Technology Data Exchange (ETDEWEB)

    Gentil-Beccot, Anne; Mele, Salvatore; /CERN; Brooks, Travis C.; /SLAC

    2009-10-17

    Contemporary scholarly discourse follows many alternative routes in addition to the three-century old tradition of publication in peer-reviewed journals. The field of High-Energy Physics (HEP) has explored alternative communication strategies for decades, initially via the mass mailing of paper copies of preliminary manuscripts, then via the inception of the first online repositories and digital libraries. This field is uniquely placed to answer recurrent questions raised by the current trends in scholarly communication: is there an advantage for scientists to make their work available through repositories, often in preliminary form? Is there an advantage to publishing in Open Access journals? Do scientists still read journals or do they use digital repositories? The analysis of citation data demonstrates that free and immediate online dissemination of preprints creates an immense citation advantage in HEP, whereas publication in Open Access journals presents no discernible advantage. In addition, the analysis of clickstreams in the leading digital library of the field shows that HEP scientists seldom read journals, preferring preprints instead.

  4. Open DOAR the Directory of Open Access Repositories

    CERN Multimedia

    CERN. Geneva

    2005-01-01

    The last year has seen wide-spread growth in the idea of using open access repositories as a part of a research institution's accepted infrastructure. Policy development from institutions and funding bodies has also supported the growth of the repository network. The next stage of expansion will be in the provision of services and cross-repository facilities and resources. Of course, it is hoped that these will then establish a feed-back loop to encourage repository population and further repository establishment, as the potential of open access to research materials is realised. The growth of repositories has been organic, with a variety of different repositories based in departments, institutions, funding agencies or subject communities, with a range of content, both in type and subject. Existing repositories are expanding their holdings, from eprints to associated research data-sets, or with learning objects and multimedia material. This presentation will look at the development of the Directory of Open Ac...

  5. Deep repository for long-lived low- and intermediate-level waste in Sweden (SFL 3-5): An international peer review of SKB 's preliminary safety assessment

    International Nuclear Information System (INIS)

    Chapman, N.; Apted, M.; Glasser, F.; Voss, C.

    2000-10-01

    systems analysis and sensitivity study, it is difficult to dispel this impression, which may be much too pessimistic. The review group believes that this may need to be soon, if the SFL 3-5 repository is indeed to be on the critical path for siting the spent fuel repository. The following points summarise some of the main findings of the review: The systematic basis of the study is rather weak. To address safety relevant issues comprehensively, a future study needs to look at a full 'systems approach' to evaluating relevant FEPs and constructing appropriate scenarios. In particular, the potential impacts of climate change, including scenarios involving permafrost and glaciation, have not been considered seriously. Alternative conceptual models of the central processes need to be evaluated. The degree of conservatism of present assumptions needs to be identified on a factor-by-factor basis. A proper sensitivity study is needed. The radionuclide inventory developed for this study is an excellent first step and has been presented extremely well. The physical and chemical compositions and properties of waste streams are also important. The review team note the necessary use of correlation factors to estimate radionuclide inventories, and several suggestions have been made for clarifying or reducing the uncertainties surrounding their application. SKB should consider how best to present the design basis and safety concept for SFL 3-5. At present, the report gives the impression of the design having evolved on a rather ad hoc basis, as no comprehensive explanation is provided of why the pre-study design was judged to be less adequate, what the design options are and how decisions have been reached on which route to adopt. A central facet of the safety study is the hydraulic cage concept. The concept needs significantly more work on its sensitivity to various factors, carried out via a proper scenario analysis. The lack of use of available site-specific geological data

  6. Modelling of radionuclide transport along the underground access structures of deep geological repositories

    Energy Technology Data Exchange (ETDEWEB)

    Poller, A. [National Cooperative for the Disposal of Radioactive Waste (NAGRA), Wettingen (Switzerland); Smith, P. [SAM Switzerland GmbH, Zuerich (Switzerland); Mayer, G.; Hayek, M. [AF-Consult Switzerland AG, Baden (Switzerland)

    2014-08-15

    The arrangement and sealing of the access routes to a deep geological repository for radioactive waste should ensure that any radionuclide release from the emplacement rooms during the post closure phase does not by-pass the geological barriers of the repository system to a significant extent. The base case of the present study, where realistic values for the hydraulic properties of the seals and the associated excavation damage zones were assumed, assesses to what extent this is actually the case for different layout variants (ramp and shaft access and shaft access only). Furthermore, as a test of robustness of system performance against uncertainties related to such seals and the associated excavation damage zones, the present study also considers a broad spectrum of calculation cases including the hypothetical possibility that the seals perform much more poorly than expected and to check whether, consequently, the repository tunnel system and the access structures may provide significant release pathways. The study considers a generic repository system for high-level waste (HLW repository) and for low- and intermediate-level waste (L/ILW repository), both with Opalinus Clay as the host rock. It also considers the alternative possibilities of a ramp or a shaft as the access route for material transport (waste packages, etc.) to the underground facilities. Additional shafts, e.g. for the transport of persons and for ventilation, are included in both cases. The overall modelling approach consists of three broad steps: (a) the network of tunnels and access structures is implemented in a flow model, which serves to calculate water flow rates along the tunnels and through the host rock; (b) all relevant transport paths are implemented in a radionuclide release and transport model, the water flow rates being obtained from the preceding flow model calculations; (c) individual effective dose rates arising from the radionuclides released from the considered repository

  7. Evaluasi Website Repositori Institusi Universitas Surabaya

    Directory of Open Access Journals (Sweden)

    Amirul Ulum

    2015-11-01

    Full Text Available The  development  of  institutional  repositories  (IRs  in Indonesia within the broader framework of open access has significant impact on preserving intellectual capital and scholarly communication. Institutional  repositories  play  a  fundamental  role  in  centralizing, preserving,  and  making  accessible  institution’s  intellectual  capital. Evaluation of the system is to determine the functionality the system to meet the users need. Using a descriptive analysis this study wants to evaluate institutional repositories of University of Surabaya. The result is usefull for institution to develop the repository systems.

  8. Preliminary analysis of the operating characteristics of a generic repository receiving facility: Status report

    International Nuclear Information System (INIS)

    1985-10-01

    The operating characteristics of a repository receiving facility structured around current technology and practices have been reviewed. Cask turnaround times and operator doses were estimated. Large throughout and long-term receiving operations at a nuclear waste repository result in an unprecedented number of casks being handled. While the current generation of material-handling equipment is adequate to process the casks, personnel radiation exposures for the generic facility analyzed are unacceptably high. This emphasizes the need for development of occupational radiation exposure control concepts for application in repository receiving facilities. 3 refs., 22 figs., 6 tabs

  9. The Control of Criticality Hazards at Harwell

    Energy Technology Data Exchange (ETDEWEB)

    Jefferson-Loveday, D. W. [Atomic Energy Research Establishment, Harwell, Berks. (United Kingdom)

    1966-05-15

    The paper describes the methods of criticality control in use at a large research establishment and looks at some of the technical and administrative problems involved in the day-to-day control. Criticality advice is given formally by an establishment committee, reinforced by specialist consultants from other U.K.A.E.A. establishments and the Authority Health and Safety Branch, with a special provision for dealing with urgent matters. The advantages of a local part-time committee in a research establishment with rapidly changing requirements are discussed together with the positive steps necessary to ensure that part-time officers and members of the committee are able to keep up to date. The total amount of fissile material in use is about 150 kg and examples are given of some of the forms and conditions of use for which there were often no published criticality precedents. To avoid unnecessary restrictions, work with small quantities is considered to be exempt from any form of criticality control. The exempt quantities are stated. Examples are given of the controls recommended for larger amounts, from hundreds of grams in physics experiments to kilograms in chemical and metallurgical operations and the handling of reactor fuel elements. The problem of providing a technical argument for safety is described in examples where lack of information has required obviously restrictive recommendations to be made. The question of inspection of operations is discussed with the view that more is to be gained by careful inspection and consultation before operations commence, as this is often an educative process for the staff involved. Methods of ensuring continued adherence to the approved conditions are examined. Some of the more difficult problems for a research establishment arise in storage of fissile material in its varied forms including fissile waste. Typical stores are described with the criticality safety controls. The aspects, which have been taken into account in

  10. Monitored Geologic Repository Project Description Document

    International Nuclear Information System (INIS)

    Curry, P. M.

    2001-01-01

    The primary objective of the Monitored Geologic Repository Project Description Document (PDD) is to allocate the functions, requirements, and assumptions to the systems at Level 5 of the Civilian Radioactive Waste Management System (CRWMS) architecture identified in Section 4. It provides traceability of the requirements to those contained in Section 3 of the ''Monitored Geologic Repository Requirements Document'' (MGR RD) (YMP 2000a) and other higher-level requirements documents. In addition, the PDD allocates design related assumptions to work products of non-design organizations. The document provides Monitored Geologic Repository (MGR) technical requirements in support of design and performance assessment in preparing for the Site Recommendation (SR) and License Application (LA) milestones. The technical requirements documented in the PDD are to be captured in the System Description Documents (SDDs) which address each of the systems at Level 5 of the CRWMS architecture. The design engineers obtain the technical requirements from the SDDs and by reference from the SDDs to the PDD. The design organizations and other organizations will obtain design related assumptions directly from the PDD. These organizations may establish additional assumptions for their individual activities, but such assumptions are not to conflict with the assumptions in the PDD. The PDD will serve as the primary link between the technical requirements captured in the SDDs and the design requirements captured in US Department of Energy (DOE) documents. The approved PDD is placed under Level 3 baseline control by the CRWMS Management and Operating Contractor (M and O) and the following portions of the PDD constitute the Technical Design Baseline for the MGR: the design characteristics listed in Table 1-1, the MGR Architecture (Section 4.1), the Technical Requirements (Section 5), and the Controlled Project Assumptions (Section 6)

  11. Monitored Geologic Repository Project Description Document

    International Nuclear Information System (INIS)

    Curry, P.

    2000-01-01

    The primary objective of the Monitored Geologic Repository Project Description Document (PDD) is to allocate the functions, requirements, and assumptions to the systems at Level 5 of the Civilian Radioactive Waste Management System (CRWMS) architecture identified in Section 4. It provides traceability of the requirements to those contained in Section 3 of the ''Monitored Geologic Repository Requirements Document'' (MGR RD) (CRWMS M and O 2000b) and other higher-level requirements documents. In addition, the PDD allocates design related assumptions to work products of non-design organizations. The document provides Monitored Geologic Repository (MGR) engineering design basis in support of design and performance assessment in preparing for the Site Recommendation (SR) and License Application (LA) milestones. The engineering design basis documented in the PDD is to be captured in the System Description Documents (SDDs) which address each of the systems at Level 5 of the CRWMS architecture. The design engineers obtain the engineering design basis from the SDDs and by reference from the SDDs to the PDD. The design organizations and other organizations will obtain design related assumptions directly from the PDD. These organizations may establish additional assumptions for their individual activities, but such assumptions are not to conflict with the assumptions in the PDD. The PDD will serve as the primary link between the engineering design basis captured in the SDDs and the design requirements captured in U.S. Department of Energy (DOE) documents. The approved PDD is placed under Level 3 baseline control by the CRWMS Management and Operating Contractor (M and O) and the following portions of the PDD constitute the Technical Design Baseline for the MGR: the design characteristics listed in Table 2-1, the MGR Architecture (Section 4.1),the Engineering Design Bases (Section 5), and the Controlled Project Assumptions (Section 6)

  12. Accelerator Physics Code Web Repository

    CERN Document Server

    Zimmermann, Frank; Bellodi, G; Benedetto, E; Dorda, U; Giovannozzi, Massimo; Papaphilippou, Y; Pieloni, T; Ruggiero, F; Rumolo, G; Schmidt, F; Todesco, E; Zotter, Bruno W; Payet, J; Bartolini, R; Farvacque, L; Sen, T; Chin, Y H; Ohmi, K; Oide, K; Furman, M; Qiang, J; Sabbi, G L; Seidl, P A; Vay, J L; Friedman, A; Grote, D P; Cousineau, S M; Danilov, V; Holmes, J A; Shishlo, A; Kim, E S; Cai, Y; Pivi, M; Kaltchev, D I; Abell, D T; Katsouleas, Thomas C; Boine-Frankenheim, O; Franchetti, G; Hofmann, I; Machida, S; Wei, J

    2006-01-01

    In the framework of the CARE HHH European Network, we have developed a web-based dynamic acceleratorphysics code repository. We describe the design, structure and contents of this repository, illustrate its usage, and discuss our future plans, with emphasis on code benchmarking.

  13. ACCELERATION PHYSICS CODE WEB REPOSITORY.

    Energy Technology Data Exchange (ETDEWEB)

    WEI, J.

    2006-06-26

    In the framework of the CARE HHH European Network, we have developed a web-based dynamic accelerator-physics code repository. We describe the design, structure and contents of this repository, illustrate its usage, and discuss our future plans, with emphasis on code benchmarking.

  14. Digitizing Dissertations for an Institutional Repository: A Process and Cost Analysis*

    Science.gov (United States)

    Piorun, Mary; Palmer, Lisa A.

    2008-01-01

    Objective: This paper describes the Lamar Soutter Library's process and costs associated with digitizing 300 doctoral dissertations for a newly implemented institutional repository at the University of Massachusetts Medical School. Methodology: Project tasks included identifying metadata elements, obtaining and tracking permissions, converting the dissertations to an electronic format, and coordinating workflow between library departments. Each dissertation was scanned, reviewed for quality control, enhanced with a table of contents, processed through an optical character recognition function, and added to the institutional repository. Results: Three hundred and twenty dissertations were digitized and added to the repository for a cost of $23,562, or $0.28 per page. Seventy-four percent of the authors who were contacted (n = 282) granted permission to digitize their dissertations. Processing time per title was 170 minutes, for a total processing time of 906 hours. In the first 17 months, full-text dissertations in the collection were downloaded 17,555 times. Conclusion: Locally digitizing dissertations or other scholarly works for inclusion in institutional repositories can be cost effective, especially if small, defined projects are chosen. A successful project serves as an excellent recruitment strategy for the institutional repository and helps libraries build new relationships. Challenges include workflow, cost, policy development, and copyright permissions. PMID:18654648

  15. Digitizing dissertations for an institutional repository: a process and cost analysis.

    Science.gov (United States)

    Piorun, Mary; Palmer, Lisa A

    2008-07-01

    This paper describes the Lamar Soutter Library's process and costs associated with digitizing 300 doctoral dissertations for a newly implemented institutional repository at the University of Massachusetts Medical School. Project tasks included identifying metadata elements, obtaining and tracking permissions, converting the dissertations to an electronic format, and coordinating workflow between library departments. Each dissertation was scanned, reviewed for quality control, enhanced with a table of contents, processed through an optical character recognition function, and added to the institutional repository. Three hundred and twenty dissertations were digitized and added to the repository for a cost of $23,562, or $0.28 per page. Seventy-four percent of the authors who were contacted (n = 282) granted permission to digitize their dissertations. Processing time per title was 170 minutes, for a total processing time of 906 hours. In the first 17 months, full-text dissertations in the collection were downloaded 17,555 times. Locally digitizing dissertations or other scholarly works for inclusion in institutional repositories can be cost effective, especially if small, defined projects are chosen. A successful project serves as an excellent recruitment strategy for the institutional repository and helps libraries build new relationships. Challenges include workflow, cost, policy development, and copyright permissions.

  16. Natural Elemental Concentrations and Fluxes: Their Use as Indicators of Repository Safety

    International Nuclear Information System (INIS)

    Miller, Bill; Lind, Andy; Savage, Dave; Maul, Philip; Robinson, Peter

    2002-03-01

    individual processes, such as groundwater discharge, river flow and erosion at specific locations. The approach can also be of value at the generic level of repository development, before site characterisation programmes have been undertaken. They could be used, for example, as a component in comparative evaluations of alternative generic disposal concepts. The objective at the generic level would be to define typical or average natural elemental concentrations and fluxes in geological systems representative of the environments which might host a repository, and to compare these with the outputs from the associated generic PAs. To facilitate the use of the natural safety indicators methodology at the generic level, this study has undertaken to bring together and to compile much of the required information. This information has been used to quantify average elemental mass fluxes at the global scale for a range of processes, including groundwater discharge, erosion and sediment transport. The point of these calculations is that they provide a baseline against which site or geological environment specific natural fluxes, from anywhere in the world, can be compared on an equal basis to evaluate if they are higher or lower than the global average and, thus, are useful for providing a broad natural context for predicted repository releases. In separate calculations, elemental mass fluxes were quantified for a number of reference environments which are chosen to be representative of the types of sites and geological systems which may host a deep repository. The reference environments were an inland pluton, basement under sedimentary cover and a sedimentary basin. The fluxes for these environments were calculated for systems with spatial scales of a few hundred square kilometres and, as such, approximate closely to the repository systems modelled in PAs because a reference environment represents the same system, with the same rock, groundwater and surface conditions as those

  17. Consistency of Network Traffic Repositories: An Overview

    NARCIS (Netherlands)

    Lastdrager, E.; Lastdrager, E.E.H.; Pras, Aiko

    2009-01-01

    Traffc repositories with TCP/IP header information are very important for network analysis. Researchers often assume that such repositories reliably represent all traffc that has been flowing over the network; little thoughts are made regarding the consistency of these repositories. Still, for

  18. 48 CFR 227.7207 - Contractor data repositories.

    Science.gov (United States)

    2010-10-01

    ... repositories. 227.7207 Section 227.7207 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS... Computer Software and Computer Software Documentation 227.7207 Contractor data repositories. Follow 227.7108 when it is in the Government's interests to have a data repository include computer software or to...

  19. Reference repository design concept for bedded salt

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, D.W.; Martin, R.W.

    1980-10-08

    A reference design concept is presented for the subsurface portions of a nuclear waste repository in bedded salt. General geologic, geotechnical, hydrologic and geochemical data as well as descriptions of the physical systems are provided for use on generic analyses of the pre- and post-sealing performance of repositories in this geologic medium. The geology of bedded salt deposits and the regional and repository horizon stratigraphy are discussed. Structural features of salt beds including discontinuities and dissolution features are presented and their effect on repository performance is discussed. Seismic hazards and the potential effects of earthquakes on underground repositories are presented. The effect on structural stability and worker safety during construction from hydrocarbon and inorganic gases is described. Geohydrologic considerations including regional hydrology, repository scale hydrology and several hydrological failure modes are presented in detail as well as the hydrological considerations that effect repository design. Operational phase performance is discussed with respect to operations, ventilation system, shaft conveyances, waste handling and retrieval systems and receival rates of nuclear waste. Performance analysis of the post sealing period of a nuclear repository is discussed, and parameters to be used in such an analysis are presented along with regulatory constraints. Some judgements are made regarding hydrologic failure scenarios. Finally, the design and licensing process, consistent with the current licensing procedure is described in a format that can be easily understood.

  20. Reference repository design concept for bedded salt

    International Nuclear Information System (INIS)

    Carpenter, D.W.; Martin, R.W.

    1980-01-01

    A reference design concept is presented for the subsurface portions of a nuclear waste repository in bedded salt. General geologic, geotechnical, hydrologic and geochemical data as well as descriptions of the physical systems are provided for use on generic analyses of the pre- and post-sealing performance of repositories in this geologic medium. The geology of bedded salt deposits and the regional and repository horizon stratigraphy are discussed. Structural features of salt beds including discontinuities and dissolution features are presented and their effect on repository performance is discussed. Seismic hazards and the potential effects of earthquakes on underground repositories are presented. The effect on structural stability and worker safety during construction from hydrocarbon and inorganic gases is described. Geohydrologic considerations including regional hydrology, repository scale hydrology and several hydrological failure modes are presented in detail as well as the hydrological considerations that effect repository design. Operational phase performance is discussed with respect to operations, ventilation system, shaft conveyances, waste handling and retrieval systems and receival rates of nuclear waste. Performance analysis of the post sealing period of a nuclear repository is discussed, and parameters to be used in such an analysis are presented along with regulatory constraints. Some judgements are made regarding hydrologic failure scenarios. Finally, the design and licensing process, consistent with the current licensing procedure is described in a format that can be easily understood

  1. Collaborative Access Control For Critical Infrastructures

    Science.gov (United States)

    Baina, Amine; El Kalam, Anas Abou; Deswarte, Yves; Kaaniche, Mohamed

    A critical infrastructure (CI) can fail with various degrees of severity due to physical and logical vulnerabilities. Since many interdependencies exist between CIs, failures can have dramatic consequences on the entire infrastructure. This paper focuses on threats that affect information and communication systems that constitute the critical information infrastructure (CII). A new collaborative access control framework called PolyOrBAC is proposed to address security problems that are specific to CIIs. The framework offers each organization participating in a CII the ability to collaborate with other organizations while maintaining control of its resources and internal security policy. The approach is demonstrated on a practical scenario involving the electrical power grid.

  2. Biosphere conceptual model development in the frame of Baita Bihor repository safety project

    International Nuclear Information System (INIS)

    Paunescu, N.; Margineanu, R.; Ene, D.

    2002-01-01

    The topic of this paper is the development of the biosphere model in the frame of the preliminary performance assessment of the Romanian National L and ILW repository, Baita-Bihor. The work presents the actual understanding of the radionuclide pathways through the repository adjacent area and their conceptualization, collection of required data, implementation of model and preliminary calculation results. The model takes into consideration a leaching scenario from the near field and the transport of radionuclides by river water. The critical group is a small community of inhabitants relying on the local resources, which constitutes an agriculture community 'small farm system'. On the basis of the defined specifications (biosphere equations and data), application of model and dose rate estimates were performed by the ABRICOT code. (author)

  3. Conceptual design of the Brazilian near surface repository

    International Nuclear Information System (INIS)

    Mourao, Rogerio P.; Freire, Carolina Braccini

    2013-01-01

    CNEN is presently in the planning phase of the implementation of a repository for low and intermediate level wastes. One of the present activities of this project is to define a concept for the disposal of radioactive wastes to be received. The conceptual design of the repository takes into account the quantities and characteristics of the waste, the disposal arrangement, the waste acceptance criteria, the site characteristics, the period of the facility operation and institutional control, the engineering barriers to be used, as well as the facility's operational aspects. The facility will be a near-surface repository, an internationally accepted concept and adopted for example in France (L'Aube repository) and Spain (El Cabril). An acceptable site for such a repository must have characteristics that minimize the risk of human exposure to the radiation and environmental contamination. For this, the chosen site must meet specific technical and socioeconomic requirements, such as favorable physiographic, meteorological, geotechnical and tectonic characteristics, low demographic density, absence of agricultural activities and mineral deposits and proximity to the paved road grid. In this work the technical and socioeconomic requirements necessary and sufficient for site selection are presented. Also discussed is the method for the establishment of the main features that the different facility's buildings must have. Since a specific site has not yet been selected, a simulated area with straight and parallel sides, no gradient, served by access road and having a surface sufficient to hold the disposal structures and support facilities, as well as the legal exclusion zones. The buildings were designed and positioned in order to meet the needs in terms of flow of waste, personnel, supplies and materials necessary to perform the activities within the enterprise. The methodology for compilation of information related to buildings is presented. This information will be

  4. Hydrothermal conditions around a radioactive waste repository

    International Nuclear Information System (INIS)

    Thunvik, R.; Braester, C.

    1981-12-01

    Numerical solutions for the hydrothermal conditions around a hard rock repository for nuclear fuel waste are presented. The objective of the present investigation is to illustrate in principle the effect of heat released from a hypothetical radioactive waste repository with regard to anisotropy in the rock permeability. Permeability and porosity are assumed to be constant or to decrease exponentially with depth. The hypothetical repository is situated below a horizontal ground surface or below the crest of a hill, and it is assumed that the water table follows the topography. Major interest in the analysis is directed towards the influence of anisotropy in the permeability on the flow patterns and travel times for water particles, being traced from the repository to the ground surface. The presented results show that anisotropy in the permeability may have a significant influence on the flow conditions around the repository and subsequently also on the travel times from the repository. (Authors)

  5. Implementation of multimode release criteria and dose standard alternatives

    International Nuclear Information System (INIS)

    Klett, R.

    1993-01-01

    The current standard that regulates the disposal of high-level radioactive wastes (HLW) and transuranic (TRU) wastes evaluates the cumulative risk of all repositories with a single derived set of generic release limits. This paper reviews the technical basis, attributes, and deficiencies of the present approach and two alternative modifications and extensions. The alternatives are the multimode release limits applied at the point of release and a dose standard alternative suggested at the first Electric Power Research Institute (EPRI) waste disposal workshop. Methods of developing and applying the alternatives are presented and some suggestions are given for incorporating them in the standards

  6. PRECLOSURE CRITICALITY ANALYSIS PROCESS REPORT

    International Nuclear Information System (INIS)

    Danise, A.E.

    2004-01-01

    This report describes a process for performing preclosure criticality analyses for a repository at Yucca Mountain, Nevada. These analyses will be performed from the time of receipt of fissile material until permanent closure of the repository (preclosure period). The process describes how criticality safety analyses will be performed for various configurations of waste in or out of waste packages that could occur during preclosure as a result of normal operations or event sequences. The criticality safety analysis considers those event sequences resulting in unanticipated moderation, loss of neutron absorber, geometric changes, or administrative errors in waste form placement (loading) of the waste package. The report proposes a criticality analyses process for preclosure to allow a consistent transition from preclosure to postclosure, thereby possibly reducing potential cost increases and delays in licensing of Yucca Mountain. The proposed approach provides the advantage of using a parallel regulatory framework for evaluation of preclosure and postclosure performance and is consistent with the U.S. Nuclear Regulatory Commission's approach of supporting risk-informed, performance-based regulation for fuel cycle facilities, ''Yucca Mountain Review Plan, Final Report'', and 10 CFR Part 63. The criticality-related criteria for ensuring subcriticality are also described as well as which guidance documents will be utilized. Preclosure operations and facilities have significant similarities to existing facilities and operations currently regulated by the U.S. Nuclear Regulatory Commission; therefore, the design approach for preclosure criticality safety will be dictated by existing regulatory requirements while using a risk-informed approach with burnup credit for in-package operations

  7. The German quality system for waste repositories

    International Nuclear Information System (INIS)

    Beckmerhagen, I.; Berg, H.P.; Brennecke, P.

    1993-01-01

    The Bundesamt fuer Strahlenschutz (BfS)--Federal Office for Radiation protection--has to guarantee that the requirements resulting from different regulations concerning planning, design, construction, operation and decommissioning of a waste repository are fulfilled. In addition, the results of the safety assessments lead to nuclear-specific requirements on the design of the plant as well as to requirements on the radioactive waste packages intended to be disposed of. Therefore, the implementation of a quality assurance (QA) and quality control (QC) system is an essential task in order to ensure that the designed quality is achieved so that the necessary precaution against damage is taken. In this paper, a detailed description of QA and QC to be applied to the planned Konrad repository as well as the basic principles and the present status of the waste package QC are indicated and discussed

  8. The fast multiple-path NUCTRAN model -- Calculating the radionuclide release from a repository

    International Nuclear Information System (INIS)

    Romero, L.; Moreno, L.; Neretnieks, I.

    1995-01-01

    The NUCTRAN model has been applied to the Swedish KBS-3 nuclear waste repository concept, where the migration of radionuclides is through various barriers and pathways. The escape of the nuclides from the canister occurs through a small hole. This hole controls the release of nuclides from the repository. NUCTRAN is a useful tool to calculate the nonstationary transport in a repository for high-level nuclear waste. The advantage of this model is the use of a coarse compartmentalization of the repository, which makes it flexible and easy to adapt to different geometries. The several radionuclide release calculations made with NUCTRAN have shown the capability of this to handle different situations rapidly and easily. The particularity of these calculations is the high accuracy obtained by using a coarse compartmentalization of the Swedish KBS-3 repository and the small requirements of computing time. At short times for short-lived nuclides, the calculated releases are exaggerated. The error can be considerably reduced by an additional subdivision of large compartments into a few compartments

  9. Critical review of the draft Area Recommendation Report and region-to-area screening methodology for the Crystalline Repository Project

    International Nuclear Information System (INIS)

    1986-01-01

    Two documents related to the Crystalline Repository Project have been reviewed. Comments and concerns related to the review of the ''Region-To-Area Screening Methodology'' and the ''Draft Area Recommendation Report'' are presented. These comments will be considered in preparation of the Final Area Recommendation Report, which will serve to formally identify potentially acceptable sites for a second repository in crystalline rock. Following a detailed review of the aforementioned documents, it is concluded that the identification of proposed potentially acceptable sites in the Draft Area Recommendation Report is based on questionable screening methodology and often incomplete data. As a result, ''favorable characteristics'' that are ascribed to each of the proposed potentially acceptable sites are, in many cases, misleading

  10. Repository operational criteria comparative analysis

    International Nuclear Information System (INIS)

    Hageman, J.P.; Chowdhury, A.H.

    1994-06-01

    The objective of the ''Repository Operational Criteria (ROC) Feasibility Studies'' (or ROC task) was to conduct comprehensive and integrated analyses of repository design, construction, and operations criteria in 10 CFR Part 60 regulations considering the interfaces among the components of the regulations and impacts of any potential changes to those regulations. The ROC task addresses regulatory criteria and uncertainties related to the preclosure aspects of the geologic repository. Those parts of 10 CFR Part 60 that require routine guidance or minor changes to the rule were addressed in Hageman and Chowdhury, 1992. The ROC task shows a possible need for further regulatory clarity, by major changes to the rule, related to the design bases and siting of a geologic repository operations area and radiological emergency planning in order to assure defense-in-depth. The analyses, presented in this report, resulted in the development and refinement of regulatory concepts and their supporting rationale for recommendations for potential major changes to 10 CFR Pan 0 regulations

  11. Coupling between water chemistry and thermal output at unsaturated repositories

    International Nuclear Information System (INIS)

    Walton, J.; LeMone, D.; Casey, D.

    1995-01-01

    This paper summarizes issues in predicting thermohydrology in the near field of a deep geological repository and the implications for performance assessment. Predicted thermohydrology depends on waste package design, and particularly on backfill materials. The coupling between solute concentrations and thermal gradients leads to a prediction of highly variable water chemistry in the near field which is radically different than the initial, undisturbed water chemistry; however, most analyses to date assume that waste package chemistry is approximately the same as initial pore water chemistry. Several alternative, simplified approaches for performance assessment are discussed

  12. What do we mean by a cold repository?

    International Nuclear Information System (INIS)

    Halsey, W.G.

    1994-01-01

    The topic of thermal loading of a potential repository at Yucca Mountain in Nevada has been the subject of intense discussion within the project technical community. While terms such as ''Hot Repository'' and ''Cold Repository'' are frequently used, they have not been clearly defined. In particular, the definition of a cold repository has remained the opinion of each individual. This has led to confusion and misunderstanding. In this paper, a number of observed definitions for a cold repository are discussed along with the technical implications, assumptions and inconsistencies. Finally, a common language is suggested

  13. Critical Period of Weed Control in Aerobic Rice

    Science.gov (United States)

    Anwar, M. P.; Juraimi, A. S.; Samedani, B.; Puteh, A.; Man, A.

    2012-01-01

    Critical period of weed control is the foundation of integrated weed management and, hence, can be considered the first step to design weed control strategy. To determine critical period of weed control of aerobic rice, field trials were conducted during 2010/2011 at Universiti Putra Malaysia. A quantitative series of treatments comprising two components, (a) increasing duration of weed interference and (b) increasing length of weed-free period, were imposed. Critical period was determined through Logistic and Gompertz equations. Critical period varied between seasons; in main season, it started earlier and lasted longer, as compared to off-season. The onset of the critical period was found relatively stable between seasons, while the end was more variable. Critical period was determined as 7–49 days after seeding in off-season and 7–53 days in main season to achieve 95% of weed-free yield, and 23–40 days in off-season and 21–43 days in main season to achieve 90% of weed-free yield. Since 5% yield loss level is not practical from economic view point, a 10% yield loss may be considered excellent from economic view point. Therefore, aerobic rice should be kept weed-free during 21–43 days for better yield and higher economic return. PMID:22778701

  14. Product traceability and quality as applied to the united states transuranic and high-level waste repository programs

    International Nuclear Information System (INIS)

    Pickering, S.Y.; Orrell, S.A.

    2000-01-01

    As with any repository program, predictions of the performance of a site over very long time frames may often meet with skepticism from the public and decision-makers, such as regulatory and governmental agencies. Experience at the WIPP and the YMP indicate that demonstrating the defensibility of data, conceptual models, computer codes, and numerical analyses is critical. Five overarching principles have been found to be the basis of a technically and publicly acceptable repository. The principles are traceability, transparency, reproducibility, retrievability, and reviews. - Traceability allows one to understand the source and justification of data and other input that generate conclusions. - Transparency allows one to follow the logic, calculations, and other operations that produce results. - Reproducibility allows one to reconstruct the results without recourse to the originator of the information. - Retrievability allows one to retrieve documentation that demonstrate these overarching principles. - Reviews ensure that the work is technically acceptable, complete, and accurate. This paper discusses how these principles are applied to the WIPP and the YMP. By setting up quality assurance and management controls (e.g., procedures, audits, peer reviews) these principles are implemented. Without successfully applying these principles the WIPP would not have gone from research to industrial maturity. The YMP is ensuring that these are implemented for activities that support licensing. Any repository program concerned with demonstrating defensibility to the public and regulators would do well by incorporating traceability, transparency, reproducibility, retrievability, and reviews into their program. (authors)

  15. Technical conservatisms in NWTS repository conceptual designs. National Waste Terminal Storage Repository No. 1: special study No. 4

    International Nuclear Information System (INIS)

    1980-09-01

    Prior studies have developed conceptual designs for National Waste Terminal Storage Repositories 1 and 2. Due to the considerable detail and volume of the documents describing these designs, it is often difficult to identify and comprehend the substantial conservatisms contained within them. This study identifies and explains the major technical conservatisms in these two conceptual designs in a concise and readily understandable format. The areas discussed include thermal loading of the geologic structure, rock mechanics and underground design, waste throughput capacity, hoisting systems, nuclear criticality safety, confinement of radioactive materials, occupational exposure and health physics, environmental effects, and cost estimates. Conservatisms are described in detail, quantified where possible, and compared to appropriate criteria

  16. Redox front formation in an uplifting sedimentary rock sequence: An analogue for redox-controlling processes in the geosphere around deep geological repositories for radioactive waste

    International Nuclear Information System (INIS)

    Yoshida, H.; Metcalfe, R.; Yamamoto, K.; Murakami, Y.; Hoshii, D.; Kanekiyo, A.; Naganuma, T.; Hayashi, T.

    2008-01-01

    Subsurface redox fronts control the mobilization and fixation of many trace elements, including potential pollutants such as certain radionuclides. Any safety assessment for a deep geological repository for radioactive wastes needs to take into account adequately the long-term redox processes in the geosphere surrounding the repository. To build confidence in understanding these processes, a redox front in a reduced siliceous sedimentary rock distributed in an uplifting area in Japan has been studied in detail. Geochemical analyses show increased concentrations of Fe and trace elements, including rare earth elements (REEs), at the redox front, even though concentrations of reduced rock matrix constituents show little change. Detailed SEM observations revealed that fossilized microorganisms composed of amorphous granules made exclusively of Fe and Si occur in the rock's pore space. Microbial 16S rDNA analysis suggests that there is presently a zonation of different bacterial groups within the redox band, and bacterial zonation played an important role in the concentration of Fe-oxyhydroxides at the redox front. These water-rock-microbe interactions can be considered analogous to the processes occurring in the redox fronts that would develop around geological repositories for radioactive waste. Once formed, the Fe-oxyhydroxides within such a front would be preserved even after reducing conditions resume following repository closure

  17. Redox front formation in an uplifting sedimentary rock sequence: An analogue for redox-controlling processes in the geosphere around deep geological repositories for radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, H. [Nagoya University Museum, Material Research Section, Furocho, Nagoya 464-8602 (Japan)], E-mail: dora@num.nagoya-u.ac.jp; Metcalfe, R. [Quintessa Japan, Queen' s Tower A7-707, Minatomirai, Yokohama 220-6007 (Japan); Yamamoto, K. [Nagoya University Museum, Material Research Section, Furocho, Nagoya 464-8602 (Japan); Murakami, Y. [Japan Atomic Energy Agency (JAEA), Tono Geoscience Centre (Japan); Hoshii, D.; Kanekiyo, A.; Naganuma, T. [Hiroshima University, Higashi Hiroshima, Kagamiyama 1-4-4 (Japan); Hayashi, T. [Asahi University, Department of Dental Pharmacology, Hozumi, Gifu (Japan)

    2008-08-15

    Subsurface redox fronts control the mobilization and fixation of many trace elements, including potential pollutants such as certain radionuclides. Any safety assessment for a deep geological repository for radioactive wastes needs to take into account adequately the long-term redox processes in the geosphere surrounding the repository. To build confidence in understanding these processes, a redox front in a reduced siliceous sedimentary rock distributed in an uplifting area in Japan has been studied in detail. Geochemical analyses show increased concentrations of Fe and trace elements, including rare earth elements (REEs), at the redox front, even though concentrations of reduced rock matrix constituents show little change. Detailed SEM observations revealed that fossilized microorganisms composed of amorphous granules made exclusively of Fe and Si occur in the rock's pore space. Microbial 16S rDNA analysis suggests that there is presently a zonation of different bacterial groups within the redox band, and bacterial zonation played an important role in the concentration of Fe-oxyhydroxides at the redox front. These water-rock-microbe interactions can be considered analogous to the processes occurring in the redox fronts that would develop around geological repositories for radioactive waste. Once formed, the Fe-oxyhydroxides within such a front would be preserved even after reducing conditions resume following repository closure.

  18. Electronic theses and dissertations management in Brazil: about digital libraries of theses and dissertations and institutional repositories

    Directory of Open Access Journals (Sweden)

    Fernando César Lima Leite

    2015-12-01

    Full Text Available Introduction: This paper presents analysis on the management of electronic theses and dissertations in the Brazilian context. The dilemmas of digital library of theses and dissertations and institutional repositories coexistence and its implications are discussed and possible paths to be considered by actors, in the institutional and national level. Objective: Present and analyze implications of the digital library of theses and dissertations and institutional repositories coexistence as management systems and, moreover, propose and discuss alternatives faced by actors responsible for its management at the institutional and national levels. Methodology: Data on the status of theses and dissertations management systems were obtained by IBICT. The analysis allowed to group the Brazilian institutions in three major categories that represent the current state of management of theses and dissertations in Brazil. Results: The settings were obtained from three major scenarios and their institutional and national implications for the management of theses and dissertations. Of these settings were listed alternative solutions to the problems identified. Conclusions: Among the findings stand out: the continuity of the IBICT’s Brazilian Digital Library of Theses and Dissertations (BDTD does not necessarily imply the continuity of the digital library of theses and dissertations; Investment in institutional repositories does not mean the end of BDTD; Part of Brazilian universities and research institutions do not enjoy conditions that allow them to effectively maintain the two systems.

  19. Thermal Management and Analysis for a Potential Yucca Mountain Repository

    International Nuclear Information System (INIS)

    Dr. A. Van Luik

    2004-01-01

    includes a summary of the technical basis that supports these evaluations. The majority of the material presented here is summarized from the Yucca Mountain Science and Engineering Report [l]. A companion paper in this publication entitled ''Characterizing the Evolution of the In-Drift Environment in a Proposed Yucca Mountain Repository'' schematically illustrates the processes being controlled through the management of thermal loading in its Figure 3

  20. Designing a Secure Storage Repository for Sharing Scientific Datasets using Public Clouds

    Energy Technology Data Exchange (ETDEWEB)

    Kumbhare, Alok [Univ. of Southern California, Los Angeles, CA (United States); Simmhan, Yogesth [Univ. of Southern California, Los Angeles, CA (United States); Prasanna, Viktor [Univ. of Southern California, Los Angeles, CA (United States)

    2011-11-14

    As Cloud platforms gain increasing traction among scientific and business communities for outsourcing storage, computing and content delivery, there is also growing concern about the associated loss of control over private data hosted in the Cloud. In this paper, we present an architecture for a secure data repository service designed on top of a public Cloud infrastructure to support multi-disciplinary scientific communities dealing with personal and human subject data, motivated by the smart power grid domain. Our repository model allows users to securely store and share their data in the Cloud without revealing the plain text to unauthorized users, the Cloud storage provider or the repository itself. The system masks file names, user permissions and access patterns while providing auditing capabilities with provable data updates.

  1. Thermal dimensioning of spent fuel repository

    International Nuclear Information System (INIS)

    Ikonen, K.

    2009-09-01

    This report contains the temperature dimensioning of the KBS-3V type nuclear fuel repository in Olkiluoto for the BWR, VVER and EPR fuel canisters, which are disposed at vertical position in the horizontal tunnels in a rectangular geometry according to the preliminary Posiva plan. This report concerns only the temperature dimensioning of the repository and does not take into account the possible restrictions caused by the stresses induced in the rock. The maximum temperature on the canister-bentonite interface is limited to the design temperature of +100 deg C. However, due to uncertainties in thermal analysis parameters (like scattering in rock conductivity or in predicted decay power) the allowable calculated maximum canister temperature is set to 90 deg C causing a safety margin of 10 deg C. The allowable temperature is controlled by adjusting the space between adjacent canisters, adjacent tunnels and the pre-cooling time affecting on power of the canisters. The temperature of canister surfaces can be determined by superposing analytic line heat source models much more efficiently than by numerical analysis, if the analytic model is first calibrated by numerical analysis (by control volume method). This was done by comparing the surface temperatures of a single canister calculated numerically and analytically. For the Olkiluoto repository of one panel having 900 canisters of BWR, VVER and EPR spent fuel was analyzed. The analyses were performed with an initial canister power of 1 700 W, 1 370 W and 1 830 W, respectively. These decay heats are obtained when the pre-cooling times of the fuels are 32.9, 29.6 and 50.3 years (the burn-up values 40, 40 and 50 MWd/kgU, respectively). The analyses gave as a result the canister spacing (6.0-10.8 m), when the tunnel spacing was 25 m, 30 m or 40 m. On the edge areas of the panel with constant canister spacing the temperatures of the canisters are lower than in the middle area of the repository. Thus it is possible to pack

  2. Criticality in Location-Based Management of Construction

    DEFF Research Database (Denmark)

    Büchmann-Slorup, Rolf

    , the current literature does not include a collected description of what constitute critical activities in LBM. Nor have the implications for scheduling and control efforts of these changes in criticality been described. Accordingly, the present thesis establishes a collected criticality principle of LBM......; highlights the implications of this alternative criticality principle to the schedule and control effort on construction projects; and suggests how time buffers should be applied on LBM projects to protect critical activities, compress project’s lead times, optimize flow, and minimize resource consumption....... The thesis offers three main results that contribute to the current LBM literature and close some of the gaps therein. The thesis conceptualizes the criticality principle of LBM by analyzing the relationship between inherent constraints in LBM and the lead times of projects. The collected criticality...

  3. Radioactive waste repository study

    International Nuclear Information System (INIS)

    1978-11-01

    This is the first part of a report of a preliminary study for Atomic Energy of Canada Limited. It considers the requirements for an underground waste repository for the disposal of wastes produced by the Canadian Nuclear Fuel Program. The following topics are discussed with reference to the repository: 1) underground layout, 2) cost estimates, 3) waste handling, 4) retrievability, decommissioning, sealing and monitoring, and 5) research and design engineering requirements. (author)

  4. MAJOR REPOSITORY DESIGN ISSUES

    International Nuclear Information System (INIS)

    JACK N. BAILEY, DWAYNE CHESTNUT, JAMES COMPTON AND RICHARD D. SNELL

    1997-01-01

    The Yucca Mountain Project is focused on producing a four-part viability assessment in late FY98. Its four components (design, performance assessment, cost estimate, and licensing development plan) must be consistent. As a tool to compare design and performance assessment options, a series of repository pictures were developed for the sequential time phases of a repository. The boundaries of the time phases correspond to evolution in the engineered barrier system (EBS)

  5. Assessment of the Durability of Cementitious Materials in Repository Environment

    International Nuclear Information System (INIS)

    Vicente, R.; Marumo, J.T.; Miyamoto, H.; Isiki, V.L.K.; Ferreira, E.G.

    2013-01-01

    The Radioactive Waste Management Laboratory of the Energy and Nuclear Research Institute is developing the concept of a borehole repository for disused sealed radioactive sources drilled in a deep granite batholite. In this concept, the annular space between the well steel casing and the geological formation is backfilled with cement paste. The hardened cement paste functions as an additional barrier against the escape of radionuclides from the repository and their migration to the environment. It also functions as an obstacle to the flow of groundwater between different layers of the geological setting crossed by the borehole. The long term behavior of hydrated cement compounds is yet incompletely known and therefore more research is needed to increase the confidence on the performance of the material under the repository conditions as required. For the repository to achieve the required performance, the cement paste must be durable. However, in a deep repository, the cementitious materials is exposed to the deleterious action of high temperatures and pressures, the radiation field created by the radioactive sources and aggressive ion species that may be present in groundwater. Furthermore, it is necessary to consider that the cement paste is unstable in the long term because its microstructure and mineralogy change with time as the cement gel components recrystallize and react chemically with materials of the repository environment. In principle, the lifetime of this material could be determined based on the study of its long-term behavior, which, in turn, could be estimated from the extrapolation of short-term results, by accelerating, under controlled laboratory conditions, the composition changes and the loss of mechanical strength and cohesion induced by any detrimental component of the repository environment. Loss of mechanical strength, dimensional variations, changes in chemical-mineralogical composition, and leaching of hydrate compounds are all possible

  6. An analysis of repository waste-handling operations

    International Nuclear Information System (INIS)

    Dennis, A.W.

    1990-09-01

    This report has been prepared to document the operational analysis of waste-handling facilities at a geologic repository for high-level nuclear waste. The site currently under investigation for the geologic repository is located at Yucca Mountain, Nye County, Nevada. The repository waste-handling operations have been identified and analyzed for the year 2011, a steady-state year during which the repository receives spent nuclear fuel containing the equivalent of 3000 metric tons of uranium (MTU) and defense high-level waste containing the equivalent of 400 MTU. As a result of this analysis, it has been determined that the waste-handling facilities are adequate to receive, prepare, store, and emplace the projected quantity of waste on an annual basis. In addition, several areas have been identified where additional work is required. The recommendations for future work have been divided into three categories: items that affect the total waste management system, operations within the repository boundary, and the methodology used to perform operational analyses for repository designs. 7 refs., 48 figs., 11 tabs

  7. Environmentally assisted cracking mechanisms in repository environments

    International Nuclear Information System (INIS)

    Mills, W.J.

    1987-02-01

    This paper assesses how environmentally assisted cracking (EAC) mechanisms in candidate container materials can be identified to enhance the accuracy of long-term projections of performance in the repository. In low and intermediate strength steels, the role of the two principal mechanisms, slip dissolution/film rupture (SD/FR) and hydrogen embrittlement (HE), is a very complex and controversial issue. No unanimity exists concerning the operative cracking mechanisms, and there is no unique or rigorous approach that would be persuasive in selecting an appropriate model. Both of the proposed mechanisms have common rate controlling processes such as surface adsorption rate, passivation rate, and oxidation rupture rate, which makes it difficult to identify the operative mechanism. Development of a quantitative model for predicting environmental effects for low-carbon steels in repository environments would provide a theoretical basis for assuring the long-term structural integrity of waste-package containment. To date, only one quantitative model has been developed. The agreement between predicted and observed behavior suggests that SD/FR processes control the environmental acceleration in crack growth rates for this class of materials. Deviations from predicted behavior due to HE effects should be uncovered experimentally. 59 refs., 4 figs., 4 tabs

  8. Method for screening the Nevada Test Site and contiguous areas for nuclear waste repository locations

    International Nuclear Information System (INIS)

    Sinnock, S.; Fernandez, J.A.; Neal, J.T.; Stephens, H.P.; Hartway, B.L.; Los Alamos Technical Associates, Inc., NM)

    1982-01-01

    This paper outlines the general concepts of a technical method for systematic screening of the Nevada Test Site (NTS), Nye County, Nevada, for potentially suitable nuclear waste repository locations. After a general discussion of the organization and the purpose of the current screening activity, the paper addresses the steps of the screening method. These steps include: hierarchically organizing technical objectives for repository performance (an objectives tree); identifying and mapping pertinent physical characteristics of a site and its setting (physical attributes); relating the physical conditions to the objectives (favorability curves); identifying alternative locations and numerically evaluating their relative merits; investigating the effects of subjective judgments on the evaluations (sensitivity analyses); documenting the assumptions, logic, and results of the method. 19 references, 10 figures

  9. On the Durability of Nuclear Waste Forms from the Perspective of Long-Term Geologic Repository Performance

    Directory of Open Access Journals (Sweden)

    Yifeng Wang

    2013-12-01

    Full Text Available High solid/water ratios and slow water percolation cause the water in a repository to quickly (on a repository time scale reach radionuclide solubility controlled by the equilibrium with alteration products; the total release of radionuclides then becomes insensitive to the dissolution rates of primary waste forms. It is therefore suggested that future waste form development be focused on conditioning waste forms or repository environments to minimize radionuclide solubility, rather than on marginally improving the durability of primary waste forms.

  10. Peculiarities of the High-Level Concrete-Encased Radwaste Repository Disposition at the Radwaste Disposal Site of the Russian Research Center 'Kurchatov Institute'

    International Nuclear Information System (INIS)

    Volkov, V.G.; Ponomarev-Stepnoi, N.N.; Gorodetsky, G.G.; Zverkov, Yu.A.; Ivanov, O.P.; Lemus, A.V.; Semenov, S.G.; Stepanov, V.E.; Chesnokov, A.V.; Shisha, A.D.

    2006-01-01

    The paper presents peculiarities of organization and performance of activities on disposition of the old repository that contained high-level waste and located at the radwaste disposal site of the Russian Research Center 'Kurchatov Institute' in Moscow. The repository was constructed in the late 1950's. A large number of cases with high-level waste were placed in the repository along with low- and intermediate-level waste. When the repository was filled in 1973, the entire radwaste mass was encased in concrete matrix which caused difficulties with the radwaste extraction and made the work on the repository disposition highly hazardous in terms of radiation conditions. Based on results of the preliminary radiation survey of the repository, technologies and equipment to be used in disposition works were selected, and a decision on construction of external radiation shielding around the repository to maintain normal radiation conditions during these works was made. Specific features of the selected radiation shielding design constructed around the repository and of a technology used for the radwaste extraction from the repository are provided. According to the technology, conventional construction machines equipped with a hydraulic hammer or a clamshell were used for destruction of the concrete-encased radwaste mass and extraction of low-level waste. Intermediate- and high-level waste was extracted by remotely controlled robots operating inside the radiation shielding structure. Video cameras and a gamma imager were used for detection of high-level waste or fragments of such radwaste in the mass concrete being destroyed and for guiding remotely controlled robots. Peculiarities of rapid control of changes in radiation conditions in the working areas are presented. This control was performed using a gamma locator with on-line transmission of its data to a PC for their processing. With disposition of this not easily accessible repository, the stage of remediation of old

  11. An Improved Method to Control the Critical Parameters of a Multivariable Control System

    Science.gov (United States)

    Subha Hency Jims, P.; Dharmalingam, S.; Wessley, G. Jims John

    2017-10-01

    The role of control systems is to cope with the process deficiencies and the undesirable effect of the external disturbances. Most of the multivariable processes are highly iterative and complex in nature. Aircraft systems, Modern Power Plants, Refineries, Robotic systems are few such complex systems that involve numerous critical parameters that need to be monitored and controlled. Control of these important parameters is not only tedious and cumbersome but also is crucial from environmental, safety and quality perspective. In this paper, one such multivariable system, namely, a utility boiler has been considered. A modern power plant is a complex arrangement of pipework and machineries with numerous interacting control loops and support systems. In this paper, the calculation of controller parameters based on classical tuning concepts has been presented. The controller parameters thus obtained and employed has controlled the critical parameters of a boiler during fuel switching disturbances. The proposed method can be applied to control the critical parameters like elevator, aileron, rudder, elevator trim rudder and aileron trim, flap control systems of aircraft systems.

  12. Memory provisions for the Manche Surface Repository

    International Nuclear Information System (INIS)

    Dumont, Jean-Noel; Espiet-Subert, Florence

    2015-01-01

    The French La Manche repository site received its last radioactive waste package in 1994. In 2003, the official surveillance phase of the closed repository started under the supervision of Andra (the national industrial operator), the French Nuclear Safety Authority (ASN) and society (e.g. the local municipalities). Florence Espiet explained that information on the existence of the repository, its content, how it was operated and how it works needs to be preserved. It also is planned to review the information periodically for a minimum of 300 years. She described the creation of two documents on memory (a detailed and a summary one), both on permanent paper, and the preservation of the land registration. The latter constitutes 'passive' provisions for preserving memory. In addition, a number of 'active' provisions are and will be put in place: guided visits, exhibitions, partnerships with organisations dealing with memory preservation, and the creation of a think tank. The latter consists of local citizens and politicians, retired employees from Andra and artists that meet several times a year and reflect on memory preservation from the perspective of, for instance, local history, education, arts and rituals. Finally, two types of markers will be used to preserve the repository's memory: i) three herbaria cataloguing the plants growing on the site of the repository, including a very short description of the repository, will be stored at different sites in France; ii) a stele indicating the main characteristics of the repository, potentially linked to an art work, will be erected at the repository

  13. Evaluation of alternative shaft-sinking techniques for high-level nuclear waste (HLW) deep geologic repositories. Final report (Task 3), June 1981-July 1982

    International Nuclear Information System (INIS)

    Gonano, L.; Findley, D.; Wildanger, W.; Gates, R.; Phillips, S.

    1983-03-01

    This report represents the results of Task 3 of US Nuclear Regulatory Commission (NRC) Contract, Technical Assistance for Repository Design. The purpose of the complete project is to provide NRC with technical assistance for the following reasons: To enable the focused, adequate review by NRC of aspects related to design and construction of an in situ test facility and final geologic repository, as presented in US Department of Energy (DOE) Site Characterization Reports (SRC), To ascertain that the DOE site characterization program will provide, as far as possible, all the information necessary to permit a review to be conducted by NRC of a license application for construction authorization. It is assumed that the Site Characterization Report and License Application will describe the exploratory shaft and concept designs for the repository shafts. This report provides a comparative evaluation of various shaft sinking techniques for production shafts for a repository. The primary comparative evaluation has been conducted for 14-ft internal diameter shafts developed in two composite media using four different methods of sinking/lining. The technical, cost and schedule comparisons draw a major distinction between shafts sunk blind and those which utilize bottom access. Based on the system of ranking introduced to grade the significant attributes of each method and the resulting design, it is concluded that for application to repository access, no one particular method of sinking exhibits a clear overall superiority. When a specific site is made available for a study of the most suitable shaft sinking methods, it will be necessary to establish actual geological conditions and technological capabilities and the comparisons presented herein reviewed accordingly

  14. Dealing with the current permissibility application for constructing a spent fuel DGR in Sweden. SKB's license applications for a spent fuel repository

    International Nuclear Information System (INIS)

    Olsson, Olle

    2014-01-01

    The nuclear power utilities in Sweden were in 1976 obliged to demonstrate a safe method for final disposal of spent fuel in order to start operation of new reactors. This initiated a comprehensive research, development and demonstration programme and the development of the KBS-method for final disposal. A new Nuclear Activities Act in 1984 gave the reactor owners full technical and financial responsibility for the waste. They gave in turn SKB the responsibility for all nuclear waste management. Reprocessing was no longer required and direct disposal of the spent fuel has, since then, been the main alternative. Alternative methods for final disposal have been evaluated and compared to the KBS-3-method but it has remained the preferred alternative. A comprehensive research, development and demonstration programme to strengthen the scientific basis and to refine the KBS-3-method has been operated by SKB since then. The site selection process for the final repository for spent nuclear fuel was initiated in 1992. The work included general siting studies at the national and the municipal level and in 2002, SKB initiated site investigations for siting of a final repository on two sites: the Simpevarp and Laxemar areas and the Forsmark area. At the same time, the work on preparing license applications to construct and operate an encapsulation plant and a final repository for spent fuel was started. In June 2009, SKB announced Forsmark as the selected site for the final repository. This paper reviews the applicable legislation and describes the license application, the licensing review and the preparations for implementation

  15. Criticality in a high level waste repository. A review of some important factors and an assessment of the lessons that can be learned from the Oklo reactors

    International Nuclear Information System (INIS)

    Oversby, V.M.

    1996-06-01

    The conditions and scenarios that might allow sufficient 239 Pu and/or 235 U to accumulate together with enough water to allow for moderation of neutron energies and thereby achieving a state where neutron-induced fission reactions could be sustained at a rate significantly above the natural rate of spontaneous fission is discussed. The uranium deposit in Oklo, Gabon, which was the site of naturally-occurring neutron-induced fission reactions approximately 2000 My ago is described. The chemistry, mineralogy, and conditions of the nuclear reactor operations are reviewed. Results of modelling the conditions for criticality at Oklo are used to estimate the amounts of spent fuel uranium that must be assembled in a favorable geometry in order to produce a similar reactive situation in a geologic repository. The amounts of uranium that must be transported and redeposited to reach a critical configuration are extremely large in relation to those that could be transported under any reasonably achievable conditions. In addition, transport and redeposition scenarios often require opposite chemical characteristics. It is concluded that the likelihood of achieving a critical condition due to accumulation of a critical mass of uranium outside the canisters after disposal is negligible. Criticality inside the canister is rendered impossible by the use of low-solubility materials inside the canisters that fill space and prevent the entry of enough water to allow moderation of neutron energies. Criticality due to plutonium outside the canister can be ruled out because it requires a series of processes, each of which has a vanishingly small probability. 25 refs, 9 tabs, 8 figs

  16. Safety analysis in subsurface repositories

    International Nuclear Information System (INIS)

    1985-06-01

    The development of mathematical models to represent the repository-geosphere-biosphere system, and the development of a structure for data acquisition, processing, and use to analyse the safety of subsurface repositories, are presented. To study the behavior of radionuclides in geosphere a laboratory to determine the hydrodynamic dispersion coefficient was constructed. (M.C.K.) [pt

  17. Alternatives for nuclear fuel disposal

    International Nuclear Information System (INIS)

    Ramirez S, J. R.; Badillo A, V.; Palacios H, J.; Celis del Angel, L.

    2010-10-01

    The spent fuel is one of the most important issues in the nuclear industry, currently spent fuel management is been cause of great amount of research, investments in the construction of repositories or constructing the necessary facilities to reprocess the fuel, and later to recycle the plutonium recovered in thermal reactors. What is the best solution? or, What is the best technology for a specific solution? Many countries have deferred the decision on selecting an option, while other works actively constructing repositories and others implementing the reprocessing facilities to recycle the plutonium obtained from nuclear spent fuel. In Mexico the nuclear power is limited to two reactors BWR type and medium size. So the nuclear spent fuel discharged has been accommodated at reactor's spent fuel pools. Originally these pools have enough capacity to accommodate spent fuel for the 40 years of designed plant operation. However, currently is under process an extended power up rate to 20% of their original power and also there are plans to extend operational life for 20 more years. Under these conditions there will not be enough room for spent fuel in the pools. So this work describes some different alternatives that have been studied in Mexico to define which will be the best alternative to follow. (Author)

  18. How many geologic repositories will be needed

    International Nuclear Information System (INIS)

    Evans, T.J.; Halstead, R.J.

    1987-01-01

    DOE's postponement of site-specific work on the second repository program had rekindled debate over the number of geologic repositories needed for disposal of high level radioactive waste. The multiple repository approach grew out of the March, 1979 IRG report, which recommended co-disposal of civilian and defense HLW in a system of regional repositories. The multiple repository approach was adopted by DOE, and incorporated in the Nuclear Waste Policy Act passed by Congress in December, 1982. Since the late 1970's, the slower than anticipated growth of the nuclear power industry has substantially reduced earlier estimates of the amount of civilian spent fuel which will require geologic disposal. Reactors currently in operation (78.5 GWe) and reactors in the construction pipeline (28 GWe) are expected to discharge about 103,200 MTU of spent fuel by the year 2036, assuming no increase in fuel burnup rate. By the year 2020, defense high level radioactive wastes equivalent to as much as 27,000 MTU could require geologic disposal. Small amounts of high level waste from other sources will also require geologic disposal. Total disposal requirements appear to be less than 140,000 MTU. The five sites nominated for the first repository, as well as hypothetical sites in granite, the host rock under primary consideration for the second repository, all appear capable of accommodating up to 140,000 MTU

  19. Site characterization plan conceptual design report for a high-level nuclear waste repository in salt, horizontal emplacment mode: Volume 1

    International Nuclear Information System (INIS)

    1987-12-01

    This Conceptual Design Report describes the conceptual design of a high-level nuclear waste repository in salt at a proposed site in Deaf Smith County, Texas. Waste receipt, processing, packaging, and other surface facility operations are described. Operations in the shafts and underground are described, including waste hoisting, transfer, and horizontal emplacement. This report specifically addresses the horizontal emplacement mode, the passive alternate design for the repository. Waste retrieval capability is described. The report includes a description of the layout of the surface, shafts, and underground. Major equipment items are identified. The report includes plans for decommissioning and sealing of the facility. The report discusses how the repository will satisfy performance objectives. Chapters are included on basis for design, design analyses, and data requirements for completion of future design efforts. 105 figs., 52 tabs

  20. Emission Control Cost-Effectiveness of Alternative-Fuel Vehicles

    OpenAIRE

    Wang, Quanlu; Sperling, Daniel; Olmstead, Janis

    1993-01-01

    Although various legislation and regulations have been adopted to promote the use of alternative-fuel vehicles for curbing urban air pollution problems, there is a lack of systematic comparisons of emission control cost-effectiveness among various alternative-fuel vehicle types. In this paper, life-cycle emission reductions and life-cycle costs were estimated for passenger cars fueled with methanol, ethanol, liquified petroleum gas, compressed natural gas, and electricity. Vehicle emission es...

  1. Digital Repositories An investigation of best practices for content recruitment to academic digital repositories and the conditions for their livelihood

    CERN Document Server

    Hagen, Reidun Anette

    2009-01-01

    A digital repository is a web accessible database, aimed at preserving the research material of an institution or scientific community. A digital repository serves as a tool for dissemination of research material and can increase the impact of the research by making it freely accessible. Digital repositories are often mentioned as a possible aid in relation to the Open Access debate; how research material should be freely accessible to anyone, anywhere at any time. However, for a digital repository to fully unleash its potential as a crucial component of Open Access, it is reliant on the ability to successfully collect and organize content. To a large extent this involves initiating self-archiving of research material by scientists throughout the academic world. This is not a trivial task, and many current repositories are inadequate in this respect, remaining empty, unvisited shelves. This thesis explores best practices for content recruitment to digital repositories, through the review of literature, and an...

  2. The importance of counting cows: Social and economic effects of a high-level nuclear waste repository in Texas

    International Nuclear Information System (INIS)

    Fleishman, J.; Brody, J.; Galavotti, C.

    1987-01-01

    Impact assessments that rely on existing records and extrapolation from broad geographic areas provide inadequate information about social and economic conditions important in siting a high-level nuclear waste repository. Texas has used an alternative approach, involving systematic surveys of representative samples of local residents, farm operators and businesses in the proposed site counties and comparison areas. Results show that this technique is useful in describing current economic conditions, including characteristics of key sectors of the economy, changes related to the siting process, and expectations that may influence investment. In addition, the surveys are useful in assessing the degree of consensus in local communities and in identifying possible differential effects of a repository on particular groups. They also provide a baseline for long-term monitoring of repository effects and contribute to their understanding of the underlying processes that shape public response to the nuclear waste program

  3. Sample management implementation plan: Salt Repository Project

    International Nuclear Information System (INIS)

    1987-01-01

    The purpose of the Sample Management Implementation Plan is to define management controls and building requirements for handling materials collected during the site characterization of the Deaf Smith County, Texas, site. This work will be conducted for the US Department of Energy Salt Repository Project Office (SRPO). The plan provides for controls mandated by the US Nuclear Regulatory Commission and the US Environmental Protection Agency. Salt Repository Project (SRP) Sample Management will interface with program participants who request, collect, and test samples. SRP Sample Management will be responsible for the following: (1) preparing samples; (2) ensuring documentation control; (3) providing for uniform forms, labels, data formats, and transportation and storage requirements; and (4) identifying sample specifications to ensure sample quality. The SRP Sample Management Facility will be operated under a set of procedures that will impact numerous program participants. Requesters of samples will be responsible for definition of requirements in advance of collection. Sample requests for field activities will be approved by the SRPO, aided by an advisory group, the SRP Sample Allocation Committee. This document details the staffing, building, storage, and transportation requirements for establishing an SRP Sample Management Facility. Materials to be managed in the facility include rock core and rock discontinuities, soils, fluids, biota, air particulates, cultural artifacts, and crop and food stuffs. 39 refs., 3 figs., 11 tabs

  4. Hydrothermal evolution of repository groundwaters in basalt

    International Nuclear Information System (INIS)

    Apps, J.A.

    1984-01-01

    Groundwaters in the near field of a radioactive waste repository in basalt will change their chemical composition in response to reactions with the basalt. These reactions will be promoted by the heat generated by the decaying waste. It is important to predict both the rate and the extent of these reactions, and the secondary minerals produced, because the alteration process controls the chemical environment affecting the corrosion of the canister, the solubility and complexation of migrating radionuclides, the reactivity of the alteration products to radionuclides sorption, and the porosity and permeability of the host rock. A comprehensive review of the literature leads to the preliminary finding that hydrothermally altering basalts in geothermal regions such as Iceland lead to a secondary mineralogy and groundwater composition similar to that expected to surround a repository. Furthermore, laboratory experiments replicating the alteration conditions approximate those observed in the field and expected in a repository. Preliminary estimates were made of the rate of hydration and devitrification of basaltic glass and the zero-order dissolution rate of basaltic materials. The rates were compared with those for rhyolitic glasses and silicate minerals. Preliminary calculations made of mixed process alteration kinetics, involving pore diffusion and surface reaction suggest that at temperatures greater than 150 0 C, alteration proceeds so rapidly as to become pervasive in normally fractured basalt exposed to higher temperatures in the field. 70 references

  5. ArrayWiki: an enabling technology for sharing public microarray data repositories and meta-analyses

    Science.gov (United States)

    Stokes, Todd H; Torrance, JT; Li, Henry; Wang, May D

    2008-01-01

    Background A survey of microarray databases reveals that most of the repository contents and data models are heterogeneous (i.e., data obtained from different chip manufacturers), and that the repositories provide only basic biological keywords linking to PubMed. As a result, it is difficult to find datasets using research context or analysis parameters information beyond a few keywords. For example, to reduce the "curse-of-dimension" problem in microarray analysis, the number of samples is often increased by merging array data from different datasets. Knowing chip data parameters such as pre-processing steps (e.g., normalization, artefact removal, etc), and knowing any previous biological validation of the dataset is essential due to the heterogeneity of the data. However, most of the microarray repositories do not have meta-data information in the first place, and do not have a a mechanism to add or insert this information. Thus, there is a critical need to create "intelligent" microarray repositories that (1) enable update of meta-data with the raw array data, and (2) provide standardized archiving protocols to minimize bias from the raw data sources. Results To address the problems discussed, we have developed a community maintained system called ArrayWiki that unites disparate meta-data of microarray meta-experiments from multiple primary sources with four key features. First, ArrayWiki provides a user-friendly knowledge management interface in addition to a programmable interface using standards developed by Wikipedia. Second, ArrayWiki includes automated quality control processes (caCORRECT) and novel visualization methods (BioPNG, Gel Plots), which provide extra information about data quality unavailable in other microarray repositories. Third, it provides a user-curation capability through the familiar Wiki interface. Fourth, ArrayWiki provides users with simple text-based searches across all experiment meta-data, and exposes data to search engine crawlers

  6. Operational safety and radiation protection considerations in designing an HLW repository in Germany

    International Nuclear Information System (INIS)

    Filbert, W.; Kreienmeyer, M.; Poehler, M.; Niehues, N.

    2008-01-01

    emplacement area) takes place in a controll ed area with restricted access. Due to the high radiation dose rate level, handling of unshielded canisters is carried out in exclusion areas (transfer cells). Other areas of the repository, in which conventional mining activities are carried out, e.g., disposal drift excavation, as well as the areas giving access to the controlled area are monitored areas. With this, the areas where the mine air can potentially be contaminated are separated from conventional areas each one having a separate ventilation regime. It should be pointed out that only conditioned waste packaged in qualified containers is acceptable for disposal, and that independent package quality control procedures prior to delivery are in place. Nevertheless, a radiation protection entrance check is performed to confirm compliance with the disposal package acceptance rules. Radiological monitoring at the repository includes dose rate surveillance at certain points of interest as well as the surveillance of exhaust air discharged from the surface buildings and from the repository mine. The instruments measure volatile aerosols and radioactive gases. Further radiological monitoring of the air in the site and its vicinity as well as of waters and soil in the surroundings is carried out. Meteorological data are also registered. The personnel is kept under radiological surveillance by measuring the air at work places, the individual dose and if necessary, the incorporation. Design dose targets for exposed workers were considered for the (in principle) avoidable incorporation of radionuclides and the unavoidable external radiation exposure. To achieve this, a specific ventilation regime has to be put in place, as well as a sound balance between radiation source shielding and shielding of the working places. Where necessary, remotely controlled waste handling will be applied. in general terms, exposure to external radiation is much more important than the effective dose by

  7. A Single Global Small-User Nuclear Repository

    International Nuclear Information System (INIS)

    Conca, J.L.; Wright, J.

    2009-01-01

    Global energy partnerships in nuclear power, proposed by France, Russia, U.S. and England, seek to address the proliferation issue by controlling fuel production and nuclear materials, removing the need for each country to develop enrichment, fabrication, recycling or disposal capabilities. Several of the large generator countries such as France, the U.S., Japan, S. Korea, Russia, the U.K., China and India, all have plans for deep geologic repositories because they anticipate sufficient waste over the next century to justify the expense of a repository. However, countries having, or planning, less than five reactors, such as Egypt, Iran, Indonesia, Brazil and about 30 other countries, will not have sufficient waste generation, or a favorable geologic site, to justify the economic and environmental issues of developing their own repository. The Salado salt formation in New Mexico, set aside for nuclear waste disposal within the 16 square-mile area by the Land Withdrawal Act of 1992, is the most optimal geologic formation for the permanent disposal of any nuclear waste and is easily able to host all of the commercial nuclear waste that will be generated in the next thousand years. The U.S. commercial nuclear waste needs presently surpass all others, and will for the foreseeable future. Hosting the relatively small amount of waste from these small-user nations will add little to U.S. waste stream while the cost/benefit analysis from the standpoint of operations, safety, geology, cost and proliferation is overwhelmingly positive for developing such a global repository. Oceanic and overland transportation, high-level disposal logistics and costs from several programs, including WIPP, have demonstrated that the operation would pay for itself from international user fees with no U.S. taxpayer dollars required and still save the world about $400 billion over 100 years. The ethical considerations alone are compelling. (authors)

  8. Washing and chilling as critical control points in pork slaughter hazard analysis and critical control point (HACCP) systems.

    Science.gov (United States)

    Bolton, D J; Pearce, R A; Sheridan, J J; Blair, I S; McDowell, D A; Harrington, D

    2002-01-01

    The aim of this research was to examine the effects of preslaughter washing, pre-evisceration washing, final carcass washing and chilling on final carcass quality and to evaluate these operations as possible critical control points (CCPs) within a pork slaughter hazard analysis and critical control point (HACCP) system. This study estimated bacterial numbers (total viable counts) and the incidence of Salmonella at three surface locations (ham, belly and neck) on 60 animals/carcasses processed through a small commercial pork abattoir (80 pigs d(-1)). Significant reductions (P HACCP in pork slaughter plants. This research will provide a sound scientific basis on which to develop and implement effective HACCP in pork abattoirs.

  9. Modelling of far-field gas migration from a deep radioactive waste repository

    International Nuclear Information System (INIS)

    Rodwell, W.R.; Nash, P.J.

    1992-01-01

    In assessing the post-closure safety of a deep radioactive waste repository, it is necessary to show that gas generated within the repository can migrate away, through the far-field geology, without affecting repository safety. This paper discusses the contribution of various mechanisms to gas migration through the far field; for example, diffusion of dissolved gas versus gas-phase movement, and bubble flow versus formation of a connected gas stream. It outlines different approaches to modelling gas movement from a repository, with simple semi-analytical models furnishing physical insights into the factors controlling gas migration in the absence of directly applicable experimental data, and more comprehensive numerical computations allowing the exploration of more detailed behaviour when appropriate data is obtained. If gas can induce groundwater movement, this could accelerate the transport of water-borne contaminants. Processes by which this could occur are noted, and the current status of work on possible effects of gas migration on groundwater movement in fractured hard rocks is indicated. 14 refs., 4 figs

  10. Building Scientific Data's list of recommended data repositories

    Science.gov (United States)

    Hufton, A. L.; Khodiyar, V.; Hrynaszkiewicz, I.

    2016-12-01

    When Scientific Data launched in 2014 we provided our authors with a list of recommended data repositories to help them identify data hosting options that were likely to meet the journal's requirements. This list has grown in size and scope, and is now a central resource for authors across the Nature-titled journals. It has also been used in the development of data deposition policies and recommended repository lists across Springer Nature and at other publishers. Each new addition to the list is assessed according to a series of criteria that emphasize the stability of the resource, its commitment to principles of open science and its implementation of relevant community standards and reporting guidelines. A preference is expressed for repositories that issue digital object identifiers (DOIs) through the DataCite system and that share data under the Creative Commons CC0 waiver. Scientific Data currently lists fourteen repositories that focus on specific areas within the Earth and environmental sciences, as well as the broad scope repositories, Dryad and figshare. Readers can browse and filter datasets published at the journal by the host repository using ISA-explorer, a demo tool built by the ISA-tools team at Oxford University1. We believe that well-maintained lists like this one help publishers build a network of trust with community data repositories and provide an important complement to more comprehensive data repository indices and more formal certification efforts. In parallel, Scientific Data has also improved its policies to better support submissions from authors using institutional and project-specific repositories, without requiring each to apply for listing individually. Online resources Journal homepage: http://www.nature.com/scientificdata Data repository criteria: http://www.nature.com/sdata/policies/data-policies#repo-criteria Recommended data repositories: http://www.nature.com/sdata/policies/repositories Archived copies of the list: https

  11. Radioactive Waste Repositories and Incentives to Local Communities

    International Nuclear Information System (INIS)

    Knapp, A.; Medakovic, S.

    2008-01-01

    Public acceptance of radioactive waste (RW) repository depends on various and often community-specific factors. Although radiological risk from a properly constructed low and intermediate level waste (LILW) repository is practically negligible, routine safety considerations will favor low populated areas and therefore probably underdeveloped communities. Repository acceptance in such communities is more likely to be facilitated by prospective benefits to local economy, such as infrastructure development and increased employment, as well as by dedicated financial incentives to the community. Direct financial compensation to the local community for acceptance of the repository has been considered in some documents in countries experienced in RW management, but it has not become a widely accepted practice. In Croatia, a possibility for such compensation is mentioned in the land use plan in conjunction with the prospective RW repository site. In Slovenia, the government has already specified the annual amount of 2.33 million euro as a compensation for 'limited land use' to be shared by local communities in the vicinity of the planned LILW repository during its operation. Applicability of the Slovenian compensations to the prospective joint Slovenian-Croatian repository is not yet clear, at least in the aspect of joint funding. The joint Slovenian-Croatian Decommissioning and LILW and SF management program for NPP Krsko from 2004 did conservatively include the compensations into the repository cost estimates, but that might not be retained in subsequent revisions of the Program. According to the agreement between governments of Slovenia and Croatia on the Nuclear power plant Krsko, Croatian side has no obligations to participate in 'public expenditures' introduced after the agreement, as would be the case of community compensations for LILW repository in Slovenia. Before further decisions on joint NPP Krsko waste management are made, including the issue of LILW

  12. Multiscale Thermohydrologic Model Analyses of Heterogeneity and Thermal-Loading Factors for the Proposed Repository at Yucca Mountain

    International Nuclear Information System (INIS)

    Glascoe, L.G.; Buscheck, T.A.; Gansemer, J.; Sun, Y.; Lee, K.

    2002-01-01

    The MultiScale ThermoHydrologic Model (MSTHM) predicts thermohydrologic (TH) conditions in emplacement drifts and the adjoining host rock throughout the proposed nuclear-waste repository at Yucca Mountain. The MSTHM is a computationally efficient approach that accounts for TH processes occurring at a scale of a few tens of centimeters around individual waste packages and emplacement drifts, and for heat flow at the multi-kilometer scale at Yucca Mountain. The modeling effort presented here is an early investigation of the repository and is simulated at a lower temperature mode and with a different panel loading than the repository currently being considered for license application. We present these recent lower temperature mode MSTHM simulations that address the influence of repository-scale thermal-conductivity heterogeneity and the influence of preclosure operational factors affecting thermal-loading conditions. We can now accommodate a complex repository layout with emplacement drifts lying in non-parallel planes using a superposition process that combines results from multiple mountain-scale submodels. This development, along with other improvements to the MSTHM, enables more rigorous analyses of preclosure operational factors. These improvements include the ability to (1) predict TH conditions on a drift-by-drift basis, (2) represent sequential emplacement of waste packages along the drifts, and (3) incorporate distance- and time-dependent heat-removal efficiency associated with drift ventilation. Alternative approaches to addressing repository-scale thermal-conductivity heterogeneity are investigated. We find that only one of the four MSTHM submodel types needs to incorporate thermal-conductivity heterogeneity. For a particular repository design, we find that the most influential parameters are (1) percolation-flux distribution, (2) thermal-conductivity heterogeneity within the host-rock units, (3) the sequencing of waste-package emplacement, and (4) the

  13. Life cycle assessment of geological repositories for the final disposal of spent fuel in Finland and Sweden

    International Nuclear Information System (INIS)

    Puhrer, A.; Bauer, C.

    2014-01-01

    This paper presents a Life Cycle Assessment (LCA) of the geological repositories for the final disposal of spent nuclear fuel in Finland and Sweden. A separate LCA has been performed for the geological spent fuel repository in each country and the results have been compared. A further benchmark comparison has been made with the LCA of the Swiss geological repository for high-level waste and spent fuel. The life cycle inventory (LCI) product system boundaries include the spent fuel repository and encapsulation facility in each country. All materials, processes, consumed utilities and transport associated with the construction, operation and closure of the repositories for spent fuel are included in the LCI. The life cycle impact assessment (LCIA) is performed using two methods: IPCC 2007 Climate Change and ReCiPe. These assessment methods return results pertaining to global warming potential (GWP) as well as a number of environmental impact categories such as human toxicity and natural land transformation. Results indicate that the use of copper for disposal canister fabrication and bentonite for repository backfilling are the causes for most of the environmental impact of the spent fuel repositories in Finland and Sweden. Alternate, less bentonite-intensive backfilling scenarios may mitigate this impact. While the Swiss bentonite consumption is lower and no copper is used for canister fabrication, the Swiss electricity and fuel consumption associated with final disposal of high-level waste and spent fuel is significantly higher than in Finland or Sweden. Approximately 1 g CO 2 -eq is emitted due to the final disposal of spent fuel and HLW per kWh of nuclear generated electricity. This represents some 10% of the emissions due to the entire nuclear energy chain and is practically negligible in the context of GHG emissions of other energy technologies. (authors)

  14. Gas generation in deep radioactive waste repositories: a review of processes, controls and models

    International Nuclear Information System (INIS)

    Jones, M.A.

    1990-10-01

    Gas generation within radioactive waste repositories may produce two general problems: 1) breaching of engineered and natural barriers due to high gas pressures; 2) enhanced radiological risk due to reduced groundwater travel times and/or greater aqueous or gaseous activities reaching the biosphere. As a result of these concerns, HMIP must be aware of the current status of relevant research, together with any associated deficiencies. This report addresses the current status of published research on near-field gas generation from worldwide sources and documents the important gas generating processes, the factors controlling them and models available to simulate them. In the absence of suitable models, outline technical specifications for corrosion and microbial degradation gas generation models are defined and the deficiencies in the current understanding of gas generation are highlighted; a conceptual research programme to correct these deficiencies is presented. (author)

  15. Safety critical application of fuzzy control

    International Nuclear Information System (INIS)

    Schildt, G.H.

    1995-01-01

    After an introduction into safety terms a short description of fuzzy logic will be given. Especially, for safety critical applications of fuzzy controllers a possible controller structure will be described. The following items will be discussed: Configuration of fuzzy controllers, design aspects like fuzzfiication, inference strategies, defuzzification and types of membership functions. As an example a typical fuzzy rule set will be presented. Especially, real-time behaviour a fuzzy controllers is mentioned. An example of fuzzy controlling for temperature control purpose within a nuclear reactor together with membership functions and inference strategy of such a fuzzy controller will be presented. (author). 4 refs, 17 figs

  16. Formulation of a strategy for monitoring control integrity in critical digital control systems

    Science.gov (United States)

    Belcastro, Celeste M.; Fischl, Robert; Kam, Moshe

    1991-01-01

    Advanced aircraft will require flight critical computer systems for stability augmentation as well as guidance and control that must perform reliably in adverse, as well as nominal, operating environments. Digital system upset is a functional error mode that can occur in electromagnetically harsh environments, involves no component damage, can occur simultaneously in all channels of a redundant control computer, and is software dependent. A strategy is presented for dynamic upset detection to be used in the evaluation of critical digital controllers during the design and/or validation phases of development. Critical controllers must be able to be used in adverse environments that result from disturbances caused by an electromagnetic source such as lightning, high intensity radiated field (HIRF), and nuclear electromagnetic pulses (NEMP). The upset detection strategy presented provides dynamic monitoring of a given control computer for degraded functional integrity that can result from redundancy management errors and control command calculation error that could occur in an electromagnetically harsh operating environment. The use is discussed of Kalman filtering, data fusion, and decision theory in monitoring a given digital controller for control calculation errors, redundancy management errors, and control effectiveness.

  17. SemanticOrganizer: A Customizable Semantic Repository for Distributed NASA Project Teams

    Science.gov (United States)

    Keller, Richard M.; Berrios, Daniel C.; Carvalho, Robert E.; Hall, David R.; Rich, Stephen J.; Sturken, Ian B.; Swanson, Keith J.; Wolfe, Shawn R.

    2004-01-01

    SemanticOrganizer is a collaborative knowledge management system designed to support distributed NASA projects, including diverse teams of scientists, engineers, and accident investigators. The system provides a customizable, semantically structured information repository that stores work products relevant to multiple projects of differing types. SemanticOrganizer is one of the earliest and largest semantic web applications deployed at NASA to date, and has been used in diverse contexts ranging from the investigation of Space Shuttle Columbia's accident to the search for life on other planets. Although the underlying repository employs a single unified ontology, access control and ontology customization mechanisms make the repository contents appear different for each project team. This paper describes SemanticOrganizer, its customization facilities, and a sampling of its applications. The paper also summarizes some key lessons learned from building and fielding a successful semantic web application across a wide-ranging set of domains with diverse users.

  18. Management of radioactive waste at Novi Han Repository

    International Nuclear Information System (INIS)

    Stefanova, I.G.; Mateeva, M.D.; Milanov, M.V.

    2002-01-01

    The Novi Han Repository is the only existing repository in Bulgaria for the disposal of radioactive waste from nuclear applications in industry, medicine and research. The repository was constructed in the early sixties according to the existing requirements. It was operated by the Institute for Nuclear Research and Nuclear Energy for more than thirty years without any accident or release of radioactivity to the environment, but without any investment for upgrading. As a consequence, the Bulgarian Nuclear Safety Authority temporarily stopped the operation of the repository in 1994. The measures for upgrading the Novi Han Repository, supported by the IAEA under TC Project BUL/4/005 'Increasing Safety of Novi Han Repository', are presented in this paper. They comprise: assessment of radionuclide inventory and future waste arisings, characterisation of disposal vaults, characterisation of the site, safety assessment, upgrading of the monitoring system, option study for the selection of treatment and conditioning processes and the development of a conceptual design for low and intermediate level waste processing and storage facility, immediate measures for improvement of the existing disposal vaults and infrastructure, construction of above-ground temporary storage structures, and resuming the operation of the Novi Han Repository. The necessary activities for re-licensing of the Novi Han Repository, construction of a waste processing and storage facility and a disposal facility for spent sealed sources are discussed. (author)

  19. CAED Document Repository

    Data.gov (United States)

    U.S. Environmental Protection Agency — Compliance Assurance and Enforcement Division Document Repository (CAEDDOCRESP) provides internal and external access of Inspection Records, Enforcement Actions, and...

  20. Sugeno integral ranking of release scenarios in a low and intermediate waste repository

    International Nuclear Information System (INIS)

    Kim, S. Ho; Kim, Tae Woon; Ha, Jae Joo

    2004-01-01

    In the present study, a multi criteria decision-making (MCDM) problem of ranking of important radionuclide release scenarios in a low and intermediate radioactive waste repository is to treat on the basis of λ-fuzzy measures and Sugeno integral. Ranking of important scenarios can lead to the provision of more effective safety measure in a design stage of the repository. The ranking is determined by a relative degree of appropriateness of scenario alternatives. To demonstrate a validation of the proposed approach to ranking of release scenarios, results of the previous AHP study are used and compared with them of the present SIAHP approach. Since the AHP approach uses importance weight based on additive probability measures, the interaction among criteria is ignored. The comparison of scenarios ranking obtained from these two approaches enables us to figure out the effect of different models for interaction among criteria

  1. Upgrading of radon's type near surface repository in Latvia

    International Nuclear Information System (INIS)

    Abramenkovs, A.

    2006-01-01

    In 1959, the Soviet government decided to construct the near surface radioactive wastes repository 'Radons' near the Baldone city. It was put in operation in 1962. The changes in the development of the repository were induced by the necessarily to upgrade it for disposal of radioactive wastes from the decommissioning of the Salaspils Research Reactor (SRR). The safety assessment of repository was performed during 2000-2001 under the PHARE project for necessary upgrades of repository. The outline design for new vaults and interim storage for long lived radioactive wastes was elaborated during 2003-2004 years. The Environmental Impact Assessment (EIA) for upgrade of Baldone repository was performed during 2004-2005 years. It was found, that additional efforts must be devoted for solution of social aspects o for successful operation and upgrade of repository. It was shown by EIA, that the local population has a negative opinion against the upgrade of repository in Latvia. The main recommendations for upgrades were connected with increasing the safety of repository, increasing of PR activities for education of society and developing of compensation mechanism for local municipality. (author)

  2. Feasibility of an International Multiple Sclerosis Rehabilitation Data Repository

    Science.gov (United States)

    Bradford, Elissa Held; Baert, Ilse; Finlayson, Marcia; Feys, Peter

    2018-01-01

    Abstract Background: Multiple sclerosis (MS) rehabilitation evidence is limited due to methodological factors, which may be addressed by a data repository. We describe the perceived challenges of, motivators for, interest in participating in, and key features of an international MS rehabilitation data repository. Methods: A multimethod sequential investigation was performed with the results of two focus groups, using nominal group technique, and study aims informing the development of an online questionnaire. Percentage agreement and key quotations illustrated questionnaire findings. Subgroup comparisons were made between clinicians and researchers and between participants in North America and Europe. Results: Rehabilitation professionals from 25 countries participated (focus groups: n = 21; questionnaire: n = 166). The top ten challenges (C) and motivators (M) identified by the focus groups were database control/management (C); ethical/legal concerns (C); data quality (C); time, effort, and cost (C); best practice (M); uniformity (C); sustainability (C); deeper analysis (M); collaboration (M); and identifying research needs (M). Percentage agreement with questionnaire statements regarding challenges to, motivators for, interest in, and key features of a successful repository was at least 80%, 85%, 72%, and 83%, respectively, across each group of statements. Questionnaire subgroup analysis revealed a few differences (P < .05), including that clinicians more strongly identified with improving best practice as a motivator. Conclusions: Findings support clinician and researcher interest in and potential for success of an international MS rehabilitation data repository if prioritized challenges and motivators are addressed and key features are included. PMID:29507539

  3. Selection of Corrosion Resistant Materials for Nuclear Waste Repositories

    International Nuclear Information System (INIS)

    R.B. Rebak

    2006-01-01

    Several countries are considering geological repositories to dispose of nuclear waste. The environment of most of the currently considered repositories will be reducing in nature, except for the repository in the US, which is going to be oxidizing. For the reducing repositories, alloys such as carbon steel, stainless steels and titanium are being evaluated. For the repository in the US, some of the most corrosion resistant commercially available alloys are being investigated. This paper presents a summary of the behavior of the different materials under consideration for the repositories and the current understanding of the degradation modes of the proposed alloys in ground water environments from the point of view of general corrosion, localized corrosion and environmentally assisted cracking

  4. Conceptual design of the Brazilian near surface repository

    Energy Technology Data Exchange (ETDEWEB)

    Mourao, Rogerio P.; Freire, Carolina Braccini, E-mail: mourao@cdtn.br, E-mail: cbf@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/UFMG-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    CNEN is presently in the planning phase of the implementation of a repository for low and intermediate level wastes. One of the present activities of this project is to define a concept for the disposal of radioactive wastes to be received. The conceptual design of the repository takes into account the quantities and characteristics of the waste, the disposal arrangement, the waste acceptance criteria, the site characteristics, the period of the facility operation and institutional control, the engineering barriers to be used, as well as the facility's operational aspects. The facility will be a near-surface repository, an internationally accepted concept and adopted for example in France (L'Aube repository) and Spain (El Cabril). An acceptable site for such a repository must have characteristics that minimize the risk of human exposure to the radiation and environmental contamination. For this, the chosen site must meet specific technical and socioeconomic requirements, such as favorable physiographic, meteorological, geotechnical and tectonic characteristics, low demographic density, absence of agricultural activities and mineral deposits and proximity to the paved road grid. In this work the technical and socioeconomic requirements necessary and sufficient for site selection are presented. Also discussed is the method for the establishment of the main features that the different facility's buildings must have. Since a specific site has not yet been selected, a simulated area with straight and parallel sides, no gradient, served by access road and having a surface sufficient to hold the disposal structures and support facilities, as well as the legal exclusion zones. The buildings were designed and positioned in order to meet the needs in terms of flow of waste, personnel, supplies and materials necessary to perform the activities within the enterprise. The methodology for compilation of information related to buildings is presented. This

  5. Computational issues in alternating projection algorithms for fixed-order control design

    DEFF Research Database (Denmark)

    Beran, Eric Bengt; Grigoriadis, K.

    1997-01-01

    Alternating projection algorithms have been introduced recently to solve fixed-order controller design problems described by linear matrix inequalities and non-convex coupling rank constraints. In this work, an extensive numerical experimentation using proposed benchmark fixed-order control design...... examples is used to indicate the computational efficiency of the method. These results indicate that the proposed alternating projections are effective in obtaining low-order controllers for small and medium order problems...

  6. Deep repository and encapsulation plant for spent nuclear fuel. Consultation and environmental impact assessment according to the Environmental Code and the Nuclear Activities Act

    International Nuclear Information System (INIS)

    2002-11-01

    As a part of its programme for siting of a deep repository for spent nuclear fuel, SKB has recently commenced site investigations at Forsmark in Oesthammar Municipality and at Simpevarp in Oskarshamn Municipality. At the same time, SKB has initiated the consultation process prior to application for permits/licences under the Environmental Code and the Nuclear Activities Act. Early consultation has been carried out for both sites, and a consultation report has been submitted to the county administrative boards in Kalmar County and Uppsala County for decisions regarding significant environmental impact. After decisions by the county administrative boards, SKB will commence the work with environmental impact assessment and extended consultation. SKB's main alternative for the encapsulation plant is siting adjacent to CLAB. In the spring of 2003, SKB will convene early consultation on the encapsulation plant. This will be followed by extended consultation up to 2005. This process will be coordinated with the extended consultation for a deep repository in Oskarshamn. An alternative is to locate the encapsulation plant at a deep repository at Forsmark. This alternative is being dealt with completely within the extended consultation for the deep repository at Forsmark. Three different permits/licences are required for both the encapsulation plant and the deep repository: a permit under the Environmental Code, a licence under the Nuclear Activities Act, and a building permit under the Planning and Building Act. Licensing under the Environmental Code and the Nuclear Activities Act takes place in parallel. The applications under both laws must include an environmental impact statement (EIS) prepared according to the rules in Chapter 6 of the Environmental Code. The same EIS is thus used in both applications. Separate EISs are prepared for the encapsulation plant and the deep repository. According to the Environmental Code, the consultation shall relate to the location, scope

  7. Numerical modeling of magma-repository interactions

    NARCIS (Netherlands)

    Bokhove, Onno

    2001-01-01

    This report explains the numerical programs behind a comprehensive modeling effort of magma-repository interactions. Magma-repository interactions occur when a magma dike with high-volatile content magma ascends through surrounding rock and encounters a tunnel or drift filled with either a magmatic

  8. Multinational/regional repository - an illusion or solution

    International Nuclear Information System (INIS)

    Mele, I.

    2006-01-01

    The concept and current status of multinational and regional repositories are presented in the paper. Particular emphasis is given to the results and findings of the recent EU project SAPIERR, investigating the feasibility of regional repository concepts in Europe. Prospects for further development of multinational repositories are also brought forward and the impact and potential benefits of this approach to our national disposal programme are discussed as well. (author)

  9. Mindfulness as an Alternative for Supporting University Student Mental Health: Cognitive-Emotional and Depressive Self-Criticism Measures

    Science.gov (United States)

    Azam, Muhammad Abid; Mongrain, Myriam; Vora, Khushboo; Pirbaglou, Meysam; Azargive, Saam; Changoor, Tina; Wayne, Noah; Guglietti, Crissa; Macpherson, Alison; Irvine, Jane; Rotondi, Michael; Smith, Dawn; Perez, Daniel; Ritvo, Paul

    2016-01-01

    Increases in university-based mental health problems require alternative mental health programs, applicable to students with elevated psychological risks due to personality traits. This study examined the cognitive-emotional outcomes of a university mindfulness meditation (MM) program and their relationship with Self-Criticism (SC), a personality…

  10. The Lincoln Repository presentation: ten reasons why you should put a copy of your work in the Repository

    OpenAIRE

    Stainthorp, Paul

    2010-01-01

    Slideshow presentation created to promote the Lincoln Repository to staff at the University of Lincoln. Consists of ten reasons why academic authors should consider depositing copies of their work in the Repository.

  11. International perspective on repositories for low level waste

    International Nuclear Information System (INIS)

    Bergstroem, Ulla; Pers, Karin; Almen, Ylva

    2011-12-01

    Nuclear energy production gives rise to different types of radioactive waste. The use of nuclear isotopes within the research, industry and medical sectors also generates radioactive waste. To protect man and the environment from radiation the waste is isolated and contained by deposition in repositories. These repositories may have various designs regarding location, barriers etc depending on the potential danger of the waste. In Sweden, low- and intermediate level waste (LILW) is disposed of in the SFR repository in Forsmark. The repository is located 60 metres down into the bedrock under the bottom of the sea and covered by 6 metres of water. It is planned to extend SFR to accommodate decommissioning waste from the dismantling of the Swedish nuclear power facilities and also for the additional operation waste caused by the planned prolonged operation time. When planning the extension consultations will be carried out with the host municipality, authorities, organisations and general public. In planning the extension, SKB has performed a worldwide compilation of how other countries have, or plan to, handle the final disposal of similar wastes. The aim of this report is to give a brief description of LILW repositories worldwide; including general brief descriptions of many facilities, descriptions of the waste and the barriers as well as safety assessments for a few chosen repositories which represent different designs. The latter is performed, where possible, to compare certain features against the Swedish SFR. To provide a background and context to this study, international organisations and conventions are also presented along with internationally accepted principles regarding the management of radioactive waste. Similar to SFR, suitable locations for the repositories have, in many countries, been found at sites that already have, or used to have nuclear activities, such as reactor sites. Abandoned and disused mines, such as the salt mines in Germany, also

  12. International perspective on repositories for low level waste

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, Ulla; Pers, Karin; Almen, Ylva (SKB International AB (Sweden))

    2011-12-15

    Nuclear energy production gives rise to different types of radioactive waste. The use of nuclear isotopes within the research, industry and medical sectors also generates radioactive waste. To protect man and the environment from radiation the waste is isolated and contained by deposition in repositories. These repositories may have various designs regarding location, barriers etc depending on the potential danger of the waste. In Sweden, low- and intermediate level waste (LILW) is disposed of in the SFR repository in Forsmark. The repository is located 60 metres down into the bedrock under the bottom of the sea and covered by 6 metres of water. It is planned to extend SFR to accommodate decommissioning waste from the dismantling of the Swedish nuclear power facilities and also for the additional operation waste caused by the planned prolonged operation time. When planning the extension consultations will be carried out with the host municipality, authorities, organisations and general public. In planning the extension, SKB has performed a worldwide compilation of how other countries have, or plan to, handle the final disposal of similar wastes. The aim of this report is to give a brief description of LILW repositories worldwide; including general brief descriptions of many facilities, descriptions of the waste and the barriers as well as safety assessments for a few chosen repositories which represent different designs. The latter is performed, where possible, to compare certain features against the Swedish SFR. To provide a background and context to this study, international organisations and conventions are also presented along with internationally accepted principles regarding the management of radioactive waste. Similar to SFR, suitable locations for the repositories have, in many countries, been found at sites that already have, or used to have nuclear activities, such as reactor sites. Abandoned and disused mines, such as the salt mines in Germany, also

  13. Data repositories for medical education research: issues and recommendations.

    Science.gov (United States)

    Schwartz, Alan; Pappas, Cleo; Sandlow, Leslie J

    2010-05-01

    The authors explore issues surrounding digital repositories with the twofold intention of clarifying their creation, structure, content, and use, and considering the implementation of a global digital repository for medical education research data sets-an online site where medical education researchers would be encouraged to deposit their data in order to facilitate the reuse and reanalysis of the data by other researchers. By motivating data sharing and reuse, investigators, medical schools, and other stakeholders might see substantial benefits to their own endeavors and to the progress of the field of medical education.The authors review digital repositories in medicine, social sciences, and education, describe the contents and scope of repositories, and present extant examples. The authors describe the potential benefits of a medical education data repository and report results of a survey of the Society for Directors of Research in Medicine Education, in which participants responded to questions about data sharing and a potential data repository. Respondents strongly endorsed data sharing, with the caveat that principal investigators should choose whether or not to share data they collect. A large majority believed that a repository would benefit their unit and the field of medical education. Few reported using existing repositories. Finally, the authors consider challenges to the establishment of such a repository, including taxonomic organization, intellectual property concerns, human subjects protection, technological infrastructure, and evaluation standards. The authors conclude with recommendations for how a medical education data repository could be successfully developed.

  14. Implementation of the Brazilian national repository

    International Nuclear Information System (INIS)

    Tello, Cledola Cassia Oliveira de

    2013-01-01

    Ionizing radiation in Brazil is used in electricity generation, medicine, industry, agriculture and for research and development purposes. All these activities can generate radioactive waste. At this point, in Brazil, the use of nuclear energy and radioisotopes justifies the construction of a national repository for radioactive wastes of low and intermediate-level. According to Federal Law No. 10308, Brazilian National Commission for Nuclear Energy (CNEN) is responsible for designing and constructing the intermediate and final storages for radioactive wastes. Additionally, a restriction on the construction of Angra 3 is that the repository is under construction until its operation start, attaining some requirements of the Brazilian Environmental Regulator (IBAMA). The RBMN Project (Repository for Low and Intermediate-Level Radioactive Wastes) aims at the implantation of a National Repository for disposal of low and intermediate-level of radiation wastes. This Project has some aspects that are unique in the Brazilian context, especially referring to the time between its construction and the end of its institutional period. This time is about 360 years, when the area will be released for unrestricted uses. It means that the Repository must be safe and secure for more than three hundred years, which is longer than half of the whole of Brazilian history. This aspect is very new for the Brazilian people, bringing a new dimension to public acceptance. Another point is this will be the first repository in South America, bringing a real challenge for the continent. The current status of the Project is summarized. (author)

  15. Minimum critical power ratio control device for nuclear power plants

    International Nuclear Information System (INIS)

    Kurosawa, Tsuneo.

    1991-01-01

    Reactor core flowrate is determined by comparing a minimum critical power ratio calculated based on the status amount of a nuclear power plant and a control value for the minimum critical power ratio that depends on the reactor core flowrate. Further, the minimum critical power ratio and a control value for the minimum critical power ratio that depends on the reactor thermal power are compared to set a reactor thermal power converted to a reactor core flowrate. Deviation between the thus determined reactor core flowrate and the present reactor core flowrate is calculated. When the obtained deviation is lower than a rated value, a reactor core flowrate set signal is generated to a reactor flowrate control means, to control the reactor power by a recycling flowrate control system of the reactor. On the other hand, when the deviation exceeds the determined value, the reactor core flowrate set signal is converted into a reactor thermal power, to control the position of control rods and control the reactor power. Then, monitor and control can be conducted safely and automatically without depending on operator's individual ability over the entire operation range corresponding to load following operation. (N.H.)

  16. Deformation stresses and mechanical behaviour of engineered barriers in the repository environment

    International Nuclear Information System (INIS)

    Ipatti, A.; Majamaeki, O.

    1991-12-01

    The report surveys functioning of the engineered barriers in the Loviisa repository under deformation stresses of the solidification product and the concrete filling material. The survey is based on the latest estimates of the waste amounts and the corresponding repository plans, and on solidification product compositions and properties. The IVOFEM and NASTRAN software was used in the structural analyses. The materials were supposed to be homogeneous and linearly elastic and dislocations small. Accordingly, the design loads were chosen conservatively so that the impacts of deformation stresses are sufficiently overestimated. A reinforced concrete container lined with cellular plastic remains a watertight structure, meeting the requirements set in view of expansion of a solidification product. In view of the stresses, the decisive time is the intermediate storage stage. The greatest stresses are found in junctions between the container wall and the bottom and cover. The concrete filling between the waste packages cannot resist the drying shrinkage and wetting expansion stresses without cracking. Concrete walls of the repository can withstand the stress caused by wetting expansion of the waste packages only when strongly reinforced. However, the forces against the walls are so big that if cracks in the concrete walls are desired to be restricted, due to reinforcement steel corrosion or wall tightness, the present type of filling material between the waste packages is not necessarily technically the best alternative

  17. Plugs for deposition tunnels in a deep geologic repository in granitic rock. Concepts and experience

    International Nuclear Information System (INIS)

    Dixon, D. A.; Boergesson, L.; Gunnarsson, D.; Hansen, J.

    2009-11-01

    Regardless of the emplacement geometry selected in a geological repository for spent nuclear fuel, there will be a requirement for the access tunnels to remain open while repository operations are ongoing. The period of repository operation will stretch for many years (decades to more than a century depending on disposal concept and number of canisters to be installed). Requirements for extended monitoring of the repository before final closure may further extend the period over which the tunnels must remain open. The intersection of the emplacement rooms/drifts and the access tunnels needs to be physically closed in order to ensure that the canisters remain undisturbed and that no undesirable hydraulic conditions are allowed to develop within the backfilled volume. As a result of these requirements, generic guidelines and design concepts have been developed for 'Plugs' that are intended to provide mechanical restraint, physical security and hydraulic control functions over the short-term (repository operational and pre-closure monitoring periods). This report focuses on the role and requirements of plugs to be installed at emplacement room/ tunnel/drift entrances or in other locations within the repository that may require installation of temporary mechanical or hydraulic control structures. These plugs are not necessarily a permanent feature of the repository and may, if required, be removed for later installation of a permanent seal. Room/Drift plugs are also by their defined function, physically accessible during repository operation so their performance can be monitored and remedial actions taken if necessary (e.g. increased seepage past the plug). A considerable number of sealing demonstrations have been undertaken at several research laboratories that are focussed on development of technologies and materials for use in isolation of spent nuclear fuel and these are briefly reviewed in this report. Additionally, technologies developed for non

  18. Plugs for deposition tunnels in a deep geologic repository in granitic rock. Concepts and experience

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, D.A. (AECL, Chalk River (Canada)); Boergesson, L. (Clay Technology, Lund (Sweden)); Gunnarsson, D. (Swedish Nuclear Fuel and Waste Management Co, Stockholm (Sweden)); Hansen, J. (Posiva Oy, Eurajoki (Finland))

    2009-11-15

    Regardless of the emplacement geometry selected in a geological repository for spent nuclear fuel, there will be a requirement for the access tunnels to remain open while repository operations are ongoing. The period of repository operation will stretch for many years (decades to more than a century depending on disposal concept and number of canisters to be installed). Requirements for extended monitoring of the repository before final closure may further extend the period over which the tunnels must remain open. The intersection of the emplacement rooms/drifts and the access tunnels needs to be physically closed in order to ensure that the canisters remain undisturbed and that no undesirable hydraulic conditions are allowed to develop within the backfilled volume. As a result of these requirements, generic guidelines and design concepts have been developed for 'Plugs' that are intended to provide mechanical restraint, physical security and hydraulic control functions over the short-term (repository operational and pre-closure monitoring periods). This report focuses on the role and requirements of plugs to be installed at emplacement room/ tunnel/drift entrances or in other locations within the repository that may require installation of temporary mechanical or hydraulic control structures. These plugs are not necessarily a permanent feature of the repository and may, if required, be removed for later installation of a permanent seal. Room/Drift plugs are also by their defined function, physically accessible during repository operation so their performance can be monitored and remedial actions taken if necessary (e.g. increased seepage past the plug). A considerable number of sealing demonstrations have been undertaken at several research laboratories that are focussed on development of technologies and materials for use in isolation of spent nuclear fuel and these are briefly reviewed in this report. Additionally, technologies developed for non

  19. The development of safeguards for geological repositories

    International Nuclear Information System (INIS)

    Van der Meer, K.

    2009-01-01

    Traditionally, research and development on geological repositories for High Level Waste (HLW) focuses on the short- and long-term safety aspects of the repository. If the repository will also be used for the disposal of spent fuel, safeguards aspects have to be taken into account. Safety and safeguards requirements may be contradictory; the safety of a geological repository is based on the non-intrusion of the geological containment, while safeguards require regular inspections of position and amount of the spent fuel. Examples to reconcile these contradictory requirements are the use of information required for the safety assessment of the geological repository for safeguards purposes and the adaptation of the safeguards approach to use non-intrusive inspection techniques. The principles of an inspection approach for a geological repository are now generally accepted within the IAEA. The practical applicability of the envisaged inspection techniques is still subject to investigation. It is specifically important for the Belgian situation that an inspection technique can be used in clay, the geological medium in which Belgium intends to dispose its HLW and spent fuel. The work reported in this chapter is the result of an international cooperation in the framework of the IAEA, in which SCK-CEN participates

  20. Investigative study of standards for digital repositories and related services

    CERN Document Server

    Foulonneau, Muriel; Badolato, Anne-Marie

    2008-01-01

    This study is meant for institutional repository managers, service providers, repository software developers and generally, all players taking an active part in the creation of the digital repository infrastructure for e-research and e-learning. It reviews the current standards, protocols and applications in the domain of digital repositories. Special attention is being paid to the interoperability of repositories to enhance the exchange of data in repositories. It aims to stimulate discussion about these topics and supports initiatives for the integration of and, where needed, development of

  1. Application of hazard analysis critical control points (HACCP) to organic chemical contaminants in food.

    Science.gov (United States)

    Ropkins, K; Beck, A J

    2002-03-01

    Hazard Analysis Critical Control Points (HACCP) is a systematic approach to the identification, assessment, and control of hazards that was developed as an effective alternative to conventional end-point analysis to control food safety. It has been described as the most effective means of controlling foodborne diseases, and its application to the control of microbiological hazards has been accepted internationally. By contrast, relatively little has been reported relating to the potential use of HACCP, or HACCP-like procedures, to control chemical contaminants of food. This article presents an overview of the implementation of HACCP and discusses its application to the control of organic chemical contaminants in the food chain. Although this is likely to result in many of the advantages previously identified for microbiological HACCP, that is, more effective, efficient, and economical hazard management, a number of areas are identified that require further research and development. These include: (1) a need to refine the methods of chemical contaminant identification and risk assessment employed, (2) develop more cost-effective monitoring and control methods for routine chemical contaminant surveillance of food, and (3) improve the effectiveness of process optimization for the control of chemical contaminants in food.

  2. Report on the access to the deposition areas of the repository. Shaft or Ramp?; Utredning roerande tilltraedesvaegar till djupfoervarets deponeringsomraaden. Schakt eller ramp?

    Energy Technology Data Exchange (ETDEWEB)

    Baeckblom, Goeran [Conrox (Sweden); Christiansson, Rolf; Hedin, Allan; Norman, Fredrik [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Lagerstedt, Leif [SwedPower AB, Stockholm (Sweden)

    2003-05-01

    During year 2002, SKB launched the site-specific engineering of the repository at the Oskarshamn and Oesthammar candidate sites. A part of the ongoing engineering work is to evaluate and possibly select type of access from surface to the underground deposition areas located at a depth of some 400 to 700 metres below the surface. The project objectives are to provide a basis for comparison and to compare generic options for access routes to the underground deposition areas, to formulate preliminary Design Justification Statements for the continued site-specific engineering of access routes to the underground repository and also to describe and exemplify methodology for optimisation of the repository engineering. In consideration of the requirements of SKB, several alternative access options are explored. The main alternatives are a ramp with one or two operational areas at the surface, a ramp with parallel excavation of a blind shaft and an alternative with shafts only. A suite of objective functions were employed in the evaluation of the main alternatives relating to long-term safety, occupational safety during construction and operation, environmental impact, sustainability of natural resources, total cost, schedules, flexibility and project risks. All alternatives studied are feasible and safe, but the alternative with a spiral ramp and a blind shaft is deemed to be the most favourable option. The alternative has the highest flexibility without any tangible disadvantages related neither to long-term safety, environmental impact nor to schedules. It is an advantage that ramp traffic is drastically reduced as rock and backfilling material is transported by the skip rather than by vehicles in the ramp, thereby reducing risks of accidents and fires in the ramp. The concurrent ramp and shaft excavation also shorten the construction period with 18 months for the underground excavations. The discounted total cost is however 100 million Swedish Kronor higher for this

  3. Thermal management and analysis for a potential yucca mountain repository

    International Nuclear Information System (INIS)

    Van Luik, A.

    2005-01-01

    presented here is summarised from the Yucca Mountain Science and Engineering Report. A companion paper in this publication entitled 'Characterizing the Evolution of the In-Drift Environment in a Proposed Yucca Mountain Repository' schematically illustrates the processes being controlled through the management of thermal loading. (author)

  4. Institutional Repositories as Infrastructures for Long-Term Preservation

    Science.gov (United States)

    Francke, Helena; Gamalielsson, Jonas; Lundell, Björn

    2017-01-01

    Introduction: The study describes the conditions for long-term preservation of the content of the institutional repositories of Swedish higher education institutions based on an investigation of how deposited files are managed with regards to file format and how representatives of the repositories describe the functions of the repositories.…

  5. Predicting spent fuel oxidation states in a tuff repository

    International Nuclear Information System (INIS)

    Einziger, R.E.; Woodley, R.E.

    1987-01-01

    Nevada Nuclear Waste Storage Investigations Project (NNWSI) is studying the suitability of the tuffaceous rocks at Yucca Mountain as a waste repository for spent fuel disposal. The oxidation state of the LWR spent fuel in the moist air environment of a tuff repository could be a significant factor in determining its leaching and dissolution characteristics. Predictions as to which oxidation states would be present are important in analyzing such a repository and thus the present study was undertaken. A set of TGA (thermogravimetric analysis) tests were conducted on well-controlled samples of irradiated PWR fuel with time and temperature as the only variables. The tests were conducted between 140 and 225 0 C for a duration up to 2200 hours. The weight gain curves were analyzed in terms of diffusion through a layer of U 3 O 7 , diffusion into the grains to form a solid solution, a simplified empirical representation of a combination of grain boundary diffusion and bulk grain oxidation. Reaction rate constants were determined in each case, but analysis of these data could not establish a definitive mechanism. 21 refs., 10 figs., 3 tabs

  6. The Analytical Repository Source-Term (AREST) model: Description and documentation

    International Nuclear Information System (INIS)

    Liebetrau, A.M.; Apted, M.J.; Engel, D.W.; Altenhofen, M.K.; Strachan, D.M.; Reid, C.R.; Windisch, C.F.; Erikson, R.L.; Johnson, K.I.

    1987-10-01

    The geologic repository system consists of several components, one of which is the engineered barrier system. The engineered barrier system interfaces with natural barriers that constitute the setting of the repository. A model that simulates the releases from the engineered barrier system into the natural barriers of the geosphere, called a source-term model, is an important component of any model for assessing the overall performance of the geologic repository system. The Analytical Repository Source-Term (AREST) model being developed is one such model. This report describes the current state of development of the AREST model and the code in which the model is implemented. The AREST model consists of three component models and five process models that describe the post-emplacement environment of a waste package. All of these components are combined within a probabilistic framework. The component models are a waste package containment (WPC) model that simulates the corrosion and degradation processes which eventually result in waste package containment failure; a waste package release (WPR) model that calculates the rates of radionuclide release from the failed waste package; and an engineered system release (ESR) model that controls the flow of information among all AREST components and process models and combines release output from the WPR model with failure times from the WPC model to produce estimates of total release. 167 refs., 40 figs., 12 tabs

  7. Socioeconomic impacts of repositories

    International Nuclear Information System (INIS)

    Thomas, J.K.; Hamm, R.R.; Murdock, S.H.

    1983-01-01

    Federal and state decision makers, community leaders, and residents must know how communities will be changed by the impacts of a high-level nuclear waste repository. This chapter identifies the factors affecting an assessment of socioeconomic impacts and the types of impacts (economic, demographic, fiscal, community service, and social) likely to occur as a result of repository development. Each of these types can be divided into standard (those which typically results from any large-scale development) and special impact categories (those which result from the fact that radioactive materials will be handled). 3 tables

  8. USAEC Controls for Nuclear Criticality Safety

    Energy Technology Data Exchange (ETDEWEB)

    McCluggage, W. C. [Division of Operational Safety, United States Atomic Energy Commission Washington, DC (United States)

    1966-05-15

    This is a paper written to provide a broad general view of the United States Atomic Energy Commission's controls for nuclear criticality safety within its own facilities. Included also is a brief' discussion of the USAEC's methods of obtaining assurance that the controls are being applied. The body of the document contains three sections. The first two describe the functions of the USAEC; the third deals with the contractors. The provisions of the Atomic Energy Act applicable to health and safety are discussed in relation to nuclear criticality safety. The use of United States Atomic Energy Commission manual chapters and Federal regulations is described. The functions of the USAEC Headquarters' offices and the operations offices are briefly outlined. Comments regarding the USAEC's inspection, auditing and appraisal programmes are included. Also briefly mentioned are the basic qualifications which must be met to become a contractor to possess and process or use fissionable materials. On the plant, factory or facility level the duties and responsibilities of industrial management are briefly outlined. The fundamental standards and their origin, together with the principal documents and guides are mentioned. The chief methods of control used by contractors operating large USAEC facilities and plants are described and compared. These include diagrams of how a typical nuclear criticality safety problem is handled from inception, design, construction and finally plant operation. Also included is a brief discussion of the contractors' methods of assuring strict employee compliance with the operating rules and limits. (author)

  9. Electronic Repository of Russian Historical Statistics

    NARCIS (Netherlands)

    Tykhonov, Vyacheslav; Kessler, Gijs; Markevich, Andrei; de Vries, Jerry

    2014-01-01

    The Electronic Repository for Russian Historical Statistics brings together data extracted from various published and unpublished sources in one place. Its principal focus is Russian economic and social history of the last three centuries (18th-21st). The repository caters to the needs of the

  10. Controlling superconductivity by tunable quantum critical points.

    Science.gov (United States)

    Seo, S; Park, E; Bauer, E D; Ronning, F; Kim, J N; Shim, J-H; Thompson, J D; Park, Tuson

    2015-03-04

    The heavy fermion compound CeRhIn5 is a rare example where a quantum critical point, hidden by a dome of superconductivity, has been explicitly revealed and found to have a local nature. The lack of additional examples of local types of quantum critical points associated with superconductivity, however, has made it difficult to unravel the role of quantum fluctuations in forming Cooper pairs. Here, we show the precise control of superconductivity by tunable quantum critical points in CeRhIn5. Slight tin-substitution for indium in CeRhIn5 shifts its antiferromagnetic quantum critical point from 2.3 GPa to 1.3 GPa and induces a residual impurity scattering 300 times larger than that of pure CeRhIn5, which should be sufficient to preclude superconductivity. Nevertheless, superconductivity occurs at the quantum critical point of the tin-doped metal. These results underline that fluctuations from the antiferromagnetic quantum criticality promote unconventional superconductivity in CeRhIn5.

  11. Integrated account of method, site selection and programme prior to the site investigation phase[Planning for a Swedish repository for spent nuclear fuels

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-12-01

    In order to dispose of the spent nuclear fuel in a safe manner, SKB plans to site a deep repository and an encapsulation plant with associated canister fabrication and transportation system. After an integrated evaluation of feasibility studies and other material, SKB will proceed with investigations of the rock and studies regarding establishment of the deep disposal system in the municipality of Oskarshamn or in Northern Uppland. The plans also include further study of the prospects for a deep repository in the municipality of Nykoeping. In the municipality of Oskarshamn, SKB plans further studies of a siting of the deep repository at Simpevarp. There SKB wants to initiate site investigations with test drilling. For the encapsulation plant, SKB wants to continue studying a siting at CLAB. In Northern Uppland, SKB plans to study two siting alternatives for the deep repository. One is Forsmark in the municipality of Oesthammar, where SKB wants to initiate a site investigation with test drilling. The other is Tierp north of Skutskaer, where SKB intends to start test drilling in an area north of Tierp. First, however, a suitable drilling area with possible transport solutions needs to be defined. This alternative requires the participation of the municipalities of both Tierp and Aelvkarleby. A siting of the encapsulation plant in Northern Uppland will also be studied. For the municipality of Nykoeping, SKB plans to conduct a new safety assessment for the Fjaellveden area, based on data from previous investigations as well as additional studies of how a deep repository could be arranged. SKB will thereby gather data from yet another geographic and geological region beyond those that are prioritized. No test drilling is planned in Nykoeping. The goal of the site investigation phase is to obtain all permits needed to build the planned facilities. It will take an estimated 7 - 8 years to assemble the requisite supporting material, carry out consultations, compile siting

  12. Microbial profile and critical control points during processing of 'robo ...

    African Journals Online (AJOL)

    Microbial profile and critical control points during processing of 'robo' snack from ... the relevant critical control points especially in relation to raw materials and ... to the quality of the various raw ingredients used were the roasting using earthen

  13. Disposal Criticality Analysis Methodology Topical Report

    International Nuclear Information System (INIS)

    Horton, D.G.

    1998-01-01

    The fundamental objective of this topical report is to present the planned risk-informed disposal criticality analysis methodology to the NRC to seek acceptance that the principles of the methodology and the planned approach to validating the methodology are sound. The design parameters and environmental assumptions within which the waste forms will reside are currently not fully established and will vary with the detailed waste package design, engineered barrier design, repository design, and repository layout. Therefore, it is not practical to present the full validation of the methodology in this report, though a limited validation over a parameter range potentially applicable to the repository is presented for approval. If the NRC accepts the methodology as described in this section, the methodology will be fully validated for repository design applications to which it will be applied in the License Application and its references. For certain fuel types (e.g., intact naval fuel), a ny processes, criteria, codes or methods different from the ones presented in this report will be described in separate addenda. These addenda will employ the principles of the methodology described in this report as a foundation. Departures from the specifics of the methodology presented in this report will be described in the addenda

  14. Disposal Criticality Analysis Methodology Topical Report

    International Nuclear Information System (INIS)

    D.G. Horton

    1998-01-01

    The fundamental objective of this topical report is to present the planned risk-informed disposal criticality analysis methodology to the NRC to seek acceptance that the principles of the methodology and the planned approach to validating the methodology are sound. The design parameters and environmental assumptions within which the waste forms will reside are currently not fully established and will vary with the detailed waste package design, engineered barrier design, repository design, and repository layout. Therefore, it is not practical to present the full validation of the methodology in this report, though a limited validation over a parameter range potentially applicable to the repository is presented for approval. If the NRC accepts the methodology as described in this section, the methodology will be fully validated for repository design applications to which it will be applied in the License Application and its references. For certain fuel types (e.g., intact naval fuel), any processes, criteria, codes or methods different from the ones presented in this report will be described in separate addenda. These addenda will employ the principles of the methodology described in this report as a foundation. Departures from the specifics of the methodology presented in this report will be described in the addenda

  15. Fons antic i repositoris universitaris a Espanya

    Directory of Open Access Journals (Sweden)

    Herrera Morillas, José Luis

    2015-12-01

    Full Text Available Es mostra la presència de col·leccions de fons antic en els repositoris de les biblioteques universitàries espanyoles després d'analitzar tots els repositoris. Per a aquesta anàlisi, com a part de la metodologia emprada, s'ha elaborat un model o llista que consta d'onze elements. Del conjunt de les universitats espanyoles, seixanta tenen repositoris, vint-i-vuit dels quals (16,8 % disposen de col·leccions de fons antic. Com que del concepte de repositori institucional no sembla desprendre's que tingui com a finalitat incloure aquest tipus de col·leccions, es reflexiona sobre la peculiaritat que una part dels repositoris universitaris espanyols inclogui col·leccions d'aquestes característiques.Se muestra la presencia de colecciones de fondo antiguo en los repositorios de las bibliotecas universitarias españolas después de analizar todos los repositorios. Para este análisis, como parte de la metodología empleada, se ha elaborado un modelo o lista que consta de once elementos. Del conjunto de las universidades españolas, sesenta cuentan con repositorios y, de estos, veintiocho (16,8 % disponen de colecciones de fondo antiguo. Debido a que del concepto de repositorio institucional no parece desprenderse que tenga como finalidad albergar este tipo de colecciones, se hace una reflexión sobre la peculiaridad de que parte de los repositorios universitarios españoles incluya colecciones de estas características.This paper uses an analysis of the repositories of Spanish universities to identify which institutions contain rare book and manuscript collections. The method used in this analysis involved examining each university on the basis of a list comprising eleven elements. A total of 60 universities were found to have repositories but only 28 (16.8 % of these contained rare book and manuscript collections. In the light of these figures, which suggest that Spanish university repositories do not generally consider the preservation of rare

  16. Decompression of magma into repository tunnels

    NARCIS (Netherlands)

    Bokhove, Onno; Woods, A.W.

    2002-01-01

    It is nontrivial to find and design safe repository sites for nuclear waste. It appears common sense to drill tunnels as repository sites in a mountain in remote and relatively dry regions. However, erosion of the waste canisters by naturally abundant chemicals in the mountains water cycle remains a

  17. Analysis of the risk assessment of a waste repository for radioactive waste from the decommissioning of nuclear power plants

    International Nuclear Information System (INIS)

    Weil, L.

    1984-09-01

    A review of decommissioning experiences and concepts is presented. The radioactive inventory of LWR of modern design at final shutdown is estimated on the basis of activation analysis and empirical data on contamination. In combination with existing types of waste packages and deposition techniques these results allow a prediction of the necessary repository volume for the decommissioning wastes in the Federal Republic of Germany. The essential element of this investigation is the development of a model for the quantitative analysis of the accident 'water intrusion' in the repository. Based on the fundamental chemical and physical processes governing nuclide migration a transport equation is obtained which can be restricted to one dimension due to the thickness and the low permeability of the geological layers above the repository. The radiological consequences are evaluated. The long-lived activation product Ni-59 turns out to be critical radionuclide. Despite a number of conservatisms in the model the evaluated doses are acceptable. The results clearly support the long term safety of the 'Konrad' mine as a low-level waste repository. (orig./HP) [de

  18. Paper and digital repositories in the United States

    Directory of Open Access Journals (Sweden)

    David F. Kohl

    2003-09-01

    Full Text Available What you've asked me to talk about today is basically what can libraries do with all the stuff they have and continue to get. Where do we put it all; what do we do with it? As we know, libraries have three core functions: collecting, organizing and preserving the key documents of the human enterprise. And, with apologies to Saint Paul, the greatest of these is preservation. For without preservation neither of the first two ultimately matter. My assignment this morning is to bring you up to date on one specific aspect of the preservation function, library repositories, and indeed, library repository developments in the US. The plan for this morning's presentation is the following: after a brief background review to give us a context for American developments we will examine first the various kinds of print repositories and then the various initiatives for electronic repositories. Because other presentations at this conference deal with electronic repositories, the main focus today will be on U.S. print repositories.

  19. Institutional Repository Sebagai Sarana Komunikasi Ilmiah Yang Sustainable Dan Reliable

    Directory of Open Access Journals (Sweden)

    Faizuddin Harliansyah

    2016-07-01

    Full Text Available Abstract; Institutional repositories development has drawn the attention of many scholars throughout the world. Using the keywords ‘institutional repositories’, there are over 300 peer-reviewed articles related on the topic has been indexed in Library, Information Science, & Technology Abstracts (LISTA and SCOPUS. There are also hundreds of theses, dissertations, and websites dedicated on this blooming trends. These are proofs that the importance of IR in higher education has been acknowledged by many professionals in the field. This paper aims at clarifying the role of repositories in strengthening scholarly communication in higher education and research institution and explaining some basic repositories concepts (types of repositories and their characteristics, as well as exploring its relations with open access movement, the development ideas, and resources that could be kept in repositories and deposit policies. Abstrak; Pengembangan institutional repositories telah banyak menyita perhatian dari kalangan ilmiah di seluruh dunia. Melalui kata kunci ‘institutional repositories’, ada lebih dari 300 artikel terulas mitra bestari yang berhubungan dengan topik ini, yang telah terindeks di Library, Information Science, & Technology Abstracts (LISTA, dan SCOPUS. Terdapat juga ratusan tesis, disertasi, dan website yang mengulas trend ini. Inilah bukti bahwa pentingnya institutional repositories (IR telah dipahami oleh para profesional di bidangnya. Tulisan ini akan menjelaskan aturan-aturan repository dalam memperkuat komunikasi ilmiah di perguruan tinggi dan lembaga riset, menjelaskan konsep-konsep dasar repositories, termasuk tipe-tipe repository dan karakteristiknya. Tulisan ini juga akan memperdalam konsep repositories dalam hubungannya dengan gerakan open access, pengembangan ide-ide, sumber-sumber ilmiah yang dapat disimpan di repositories, serta kebijakan penyimpanan di dalamnya.

  20. Alternatives to neonicotinoid insecticides for pest control: case studies in agriculture and forestry.

    Science.gov (United States)

    Furlan, Lorenzo; Kreutzweiser, David

    2015-01-01

    Neonicotinoid insecticides are widely used for control of insect pests around the world and are especially pervasive in agricultural pest management. There is a growing body of evidence indicating that the broad-scale and prophylactic uses of neonicotinoids pose serious risks of harm to beneficial organisms and their ecological function. This provides the impetus for exploring alternatives to neonicotinoid insecticides for controlling insect pests. We draw from examples of alternative pest control options in Italian maize production and Canadian forestry to illustrate the principles of applying alternatives to neonicotinoids under an integrated pest management (IPM) strategy. An IPM approach considers all relevant and available information to make informed management decisions, providing pest control options based on actual need. We explore the benefits and challenges of several options for management of three insect pests in maize crops and an invasive insect pest in forests, including diversifying crop rotations, altering the timing of planting, tillage and irrigation, using less sensitive crops in infested areas, applying biological control agents, and turning to alternative reduced risk insecticides. Continued research into alternatives is warranted, but equally pressing is the need for information transfer and training for farmers and pest managers and the need for policies and regulations to encourage the adoption of IPM strategies and their alternative pest control options.

  1. Environmental issues of repository licensing: an evaluation of a hypothetical high-level radioactive waste repository

    International Nuclear Information System (INIS)

    Owen, J.L.; McGinnis, J.T.; Harper, C.M.; Battelle Columbus Labs., OH)

    1982-01-01

    This paper presents results of an environmental assessment conducted under the direction of the Office of Nuclear Waste Isolation as part of the National Waste Terminal Storage program. The study defined a range of potential environmental effects of constructing, operating, decommissioning, and long-term isolation of a nuclear waste repository. The analytical methodology used to determine potential environmental effects required definition of a hypothetical environmental setting and repository. Potentially applicable regulatory requirements were identified and were used as guidelines to evaluate permitting feasibility. The environmental effects of repository development were analyzed for the two major time periods of concern: short term (the period of construction, operation, and decommissioning) and long term (the isolation period after decommissioning). As a result of this analysis, major environmental uncertainties and issues were identified. 11 references, 5 figures

  2. Numerical versus analytical Ic(H) patterns in Josephson junctions with periodically alternating critical current density

    International Nuclear Information System (INIS)

    Lazarides, N

    2004-01-01

    An analytical expression for the magnetic-field-dependent critical current I c (H) of Josephson junctions with periodically alternating critical current density J c (x) is derived within the uniform field approximation. Comparison with numerically calculated I c (H) patterns for junctions with identical, thick, periodically arranged defects with the corresponding analytical expression reveals fair agreement for a wide range of parameters, due to increased characteristic length. Based on qualitative arguments, we give the dependence of the new characteristic length on the geometrical parameters of the junction, which is in agreement with self-consistent calculations with the static sine-Gordon equation. The analytical expression captures the observed qualitative features of the I c (H) patterns, while it is practically exact for short junctions or high fields. It also produces the shift of the major peak from the zero-field position of the standard Fraunhofer pattern to another position related to the periodicity of the critical current density in φ-junctions

  3. Abadia de Goias repository: design conception; Repositorio de Abadia de Goias: concepcao de projeto

    Energy Technology Data Exchange (ETDEWEB)

    Martin Alves, Antonio Sergio de; Santos, Cicero Durval Pacifici dos; Passos, Erivaldo Mario dos; Coutinho, Fernando Paulo Millen [NUCLEN, Rio de Janeiro, RJ (Brazil)

    1995-12-31

    In this paper have been presented the criteria, the methodologies and the parameters that were utilized for the design of Abadia de Goias Repository. Hereby the purpose is to show in a succinct way the know how that has been acquired for the design of a LLW and ILW repository. This paper presents information and details concerning to the various phases of the design, beginning with the data collecting activity, the safety analysis elaboration up to the definition of the final concept of the repository and of the required infrastructure work. The safety analysis, based on the Cs-137 migration through the groundwater, made possible at first to determine the places of the repository site where the population is not allowed to drill wells. The analysis allowed also the institutional control period calculation based on the maximum concentration of Cs-137 in the aquifer as well as in the intrusion models. (author). 16 refs., 3 figs., 1 tab.

  4. The determinants of alternative RNA splicing in human cells.

    Science.gov (United States)

    Ramanouskaya, Tatsiana V; Grinev, Vasily V

    2017-12-01

    Alternative splicing represents an important level of the regulation of gene function in eukaryotic organisms. It plays a critical role in virtually every biological process within an organism, including regulation of cell division and cell death, differentiation of tissues in the embryo and the adult organism, as well as in cellular response to diverse environmental factors. In turn, studies of the last decade have shown that alternative splicing itself is controlled by different mechanisms. Unfortunately, there is no clear understanding of how these diverse mechanisms, or determinants, regulate and constrain the set of alternative RNA species produced from any particular gene in every cell of the human body. Here, we provide a consolidated overview of alternative splicing determinants including RNA-protein interactions, epigenetic regulation via chromatin remodeling, coupling of transcription-to-alternative splicing, effect of secondary structures in pre-RNA, and function of the RNA quality control systems. We also extensively and critically discuss some mechanistic insights on coordinated inclusion/exclusion of exons during the formation of mature RNA molecules. We conclude that the final structure of RNA is pre-determined by a complex interplay between cis- and trans-acting factors. Altogether, currently available empirical data significantly expand our understanding of the functioning of the alternative splicing machinery of cells in normal and pathological conditions. On the other hand, there are still many blind spots that require further deep investigations.

  5. Evaluation of repository safety

    Energy Technology Data Exchange (ETDEWEB)

    Sagar, B.; Patrick, W.; Dasgupta, B.; Mohanty, S. [Center for Nuclear Waste Regulatory Analyses, San Antonio (United States)

    2002-07-01

    The United States high-level waste program requires evaluation of radiological safety during two distinct time intervals. The first interval, commonly referred to as the preclosure period, deals with receipt of waste at the site, transfer into disposal containers, if needed, emplacement in the underground openings, monitoring and maintenance activities, backfill and closure of the underground openings, and decontamination and decommissioning of the surface facilities of the geologic repository. The preclosure period may extend from a few tens of years to as long as a few hundred of years, depending on repository design and societal norms regarding a final decision to permanently seal the repository. During the preclosure or operational period, performance confirmation studies are conducted to provide a basis for updating and reevaluating estimates of postclosure performance and, finally, to provide a basis for a closure decision. The postclosure period during which expected repository performance must meet certain standards may range from ten thousands years, as it does in the United States, to millions of years, as it does in some European nations. Waste handling operations in the preclosure period are to be evaluated in relation to their potential effect on workers, members of general public, and the general environment. During this period, releases of radioactivity are to be monitored and appropriate actions taken whenever established limits are approached or exceeded. Preclosure safety is highly dependent on facility design, operational hardware and automated systems, operational sequences, and reliability of humans involved in operations. Preclosure safety analyses conducted before operations begin play a major role in the design process, selection of equipment, and development of operational procedures. Because of the complexity, duration, and spatial scales of the operations, analyses are conducted using mathematical models implemented in computer codes

  6. Evaluation of repository safety

    International Nuclear Information System (INIS)

    Sagar, B.; Patrick, W.; Dasgupta, B.; Mohanty, S.

    2002-01-01

    The United States high-level waste program requires evaluation of radiological safety during two distinct time intervals. The first interval, commonly referred to as the preclosure period, deals with receipt of waste at the site, transfer into disposal containers, if needed, emplacement in the underground openings, monitoring and maintenance activities, backfill and closure of the underground openings, and decontamination and decommissioning of the surface facilities of the geologic repository. The preclosure period may extend from a few tens of years to as long as a few hundred of years, depending on repository design and societal norms regarding a final decision to permanently seal the repository. During the preclosure or operational period, performance confirmation studies are conducted to provide a basis for updating and reevaluating estimates of postclosure performance and, finally, to provide a basis for a closure decision. The postclosure period during which expected repository performance must meet certain standards may range from ten thousands years, as it does in the United States, to millions of years, as it does in some European nations. Waste handling operations in the preclosure period are to be evaluated in relation to their potential effect on workers, members of general public, and the general environment. During this period, releases of radioactivity are to be monitored and appropriate actions taken whenever established limits are approached or exceeded. Preclosure safety is highly dependent on facility design, operational hardware and automated systems, operational sequences, and reliability of humans involved in operations. Preclosure safety analyses conducted before operations begin play a major role in the design process, selection of equipment, and development of operational procedures. Because of the complexity, duration, and spatial scales of the operations, analyses are conducted using mathematical models implemented in computer codes

  7. Semantic Linking of Learning Object Repositories to DBpedia

    Science.gov (United States)

    Lama, Manuel; Vidal, Juan C.; Otero-Garcia, Estefania; Bugarin, Alberto; Barro, Senen

    2012-01-01

    Large-sized repositories of learning objects (LOs) are difficult to create and also to maintain. In this paper we propose a way to reduce this drawback by improving the classification mechanisms of the LO repositories. Specifically, we present a solution to automate the LO classification of the Universia repository, a collection of more than 15…

  8. Interaction of nuclear waste panels with shafts and access ramps for a potential repository at Yucca Mountain: Nevada Nuclear Waste Storage Investigations Project

    International Nuclear Information System (INIS)

    St John, C.M.

    1987-09-01

    A series of two-dimensional and three-dimensional analyses of a potential nuclear waste repository at Yucca Mountain were performed to estimate the thermal stresses that would be experienced at the possible locations of shafts or ramps providing access to the repository horizon. Two alternative assumptions were made for the initial state of stress, and calculations were performed to investigate behavior at repository scale. The computed states of stress were also used as boundary conditions for a series of analyses of the access ramps and vertical shafts. The results of the repository scale analyses indicated that there is a region above the repository horizon where the horizontal stresses are reduced as a consequence of the thermal loads imposed by waste emplacement. If the initial state of stress is relatively low then the total horizontal stresses near the ground surface above the repository may be tensile. An evaluation of the total stress state relative to the strength of the rock matrix and vertical and near vertical joints indicates that there is no potential for development of new fractures in the matrix, but joints near the surface could be activated if the initial stress state is low. 13 refs., 24 figs., 4 tabs

  9. NIDDK Central Repository

    Data.gov (United States)

    U.S. Department of Health & Human Services — The NIDDK Central Repository stores biosamples, genetic and other data collected in designated NIDDK-funded clinical studies. The purpose of the NIDDK Central...

  10. Cryopreservation in fish: current status and pathways to quality assurance and quality control in repository development.

    Science.gov (United States)

    Torres, Leticia; Hu, E; Tiersch, Terrence R

    2016-01-07

    Cryopreservation in aquatic species in general has been constrained to research activities for more than 60 years. Although the need for application and commercialisation pathways has become clear, the lack of comprehensive quality assurance and quality control programs has impeded the progress of the field, delaying the establishment of germplasm repositories and commercial-scale applications. In this review we focus on the opportunities for standardisation in the practices involved in the four main stages of the cryopreservation process: (1) source, housing and conditioning of fish; (2) sample collection and preparation; (3) freezing and cryogenic storage of samples; and (4) egg collection and use of thawed sperm samples. In addition, we introduce some key factors that would assist the transition to commercial-scale, high-throughput application.

  11. Researching radioactive waste disposal. [Underground repository

    Energy Technology Data Exchange (ETDEWEB)

    Feates, F; Keen, N [UKAEA Research Group, Harwell. Atomic Energy Research Establishment

    1976-02-16

    At present it is planned to use the vitrification process to convert highly radioactive liquid wastes, arising from nuclear power programme, into glass which will be contained in steel cylinders for storage. The UKAEA in collaboration with other European countries is currently assessing the relative suitability of various natural geological structures as final repositories for the vitrified material. The Institute of Geological Sciences has been commissioned to specify the geological criteria that should be met by a rock structure if it is to be used for the construction of a repository though at this stage disposal sites are not being sought. The current research programme aims to obtain basic geological data about the structure of the rocks well below the surface and is expected to continue for at least three years. The results in all the European countries will then be considered so that the United Kingdom can choose a preferred method for isolating their wastes. It is only at that stage that a firm commitment may be made to select a site for a potential repository, when a far more detailed scientific research study will be instituted. Heat transfer problems and chemical effects which may occur within and around repositories are being investigated and a conceptual design study for an underground repository is being prepared.

  12. Dounreay: an alternative development

    International Nuclear Information System (INIS)

    Low, K.

    1990-01-01

    With the Government decision to phase out the Fast Reactor at Dounreay there is a need to find alternative employment in the area. Traditionally Caithness is an area of farming, fishing and tourism which could be damaged if Dounreay were to be made a nuclear waste repository. The suggestion is that Dounreay should become a centre for research, development and subsequent manufacture of renewable energy sources and devices to harness renewable energy. The Scottish coastline has potential for wind and wave power developments and this could lead to a whole industry in the future. (UK)

  13. Cross Institutional Cooperation on a Shared Bit Repository

    DEFF Research Database (Denmark)

    Zierau, Eld; Kejser, Ulla Bøgvad

    2013-01-01

    This paper explores how independent institutions, such as archives and libraries, can cooperate on managing a shared bit repository with bit preservation, in order to use their resources for preservation in a more cost-effective way. It uses the OAIS Reference Model to provide a framework...... for systematically analysing institutions technical and organisational requirements for a remote bit repository. Instead of viewing a bit repository simply as Archival Storage for the institutions repositories, we argue for viewing it as consisting of a subset of functions from all entities defined by the OAIS...... Reference Model. The work is motivated by and used in a current Danish feasibility study for establishing a national bit repository. The study revealed that depending on their missions and the collections they hold, the institutions have varying requirements e.g. for bit safety, accessibility...

  14. Cross Institutional Cooperation on a Shared Bit Repository

    DEFF Research Database (Denmark)

    Zierau, Eld; Kejser, Ulla Bøgvad

    2010-01-01

    This paper explores how independent institutions, such as archives and libraries, can cooperate on managing a shared bit repository with bit preservation in order to use their resources for preservation n in a more cost-effective way. It uses the OAIS Reference Model to provide a framework...... for systematically analysing the technical and organizational requirements of institutions for a remote bit repository. Instead of viewing a bit repository simply as Archival Storage for the institutions’ repositories, we argue for viewing it as consisting of a subset of functions from all entities defined...... by the OAIS Reference Model. The work is motivated by and used in a current Danish feasibility study for establishing a national bit repository. The study revealed that depending on their missions and the collections they hold, the institutions have varying requirements, such as for bit safety, accessibility...

  15. Deep repository for spent nuclear fuel. Facility description - Layout E. Spiral ramp with one operational area

    International Nuclear Information System (INIS)

    Pettersson, Stig; Forsgren, Ebbe; Lange, Fritz

    2002-04-01

    This report documents a proposal for the design of the deep repository for spent nuclear fuel. The proposal is based on the principles that were formulated in the original KBS-3 study, but has been supplemented by investigations and experience to reflect current knowledge. The purpose of the report is to provide an integrated picture of the deep repository, as a basis for SKB's other work, e.g. environmental impact assessments, transport systems, safety issues and alternative locations, and to provide a co-ordinated account of the conditions and requirements concerning all of the necessary functions in the deep repository in order to have a well functioning facility. In addition, it should be possible to use the report as: a tool in the task of achieving a co-ordinated, safe and accepted design for the facility, a basis for further planning and costing, a basis for adaptation to geographic and other conditions for the particular location, a basis for information material, both within SKB and for interested parties outside, such as public authorities, municipalities and the general public. The capacity of the deep repository has been chosen on the basis of 40 years of operation of the Swedish nuclear power reactors, which will produce approximately 9,000 tons of uranium, equivalent to approximately 4,500 canisters. The design outlined is based on theoretical analyses of functions, safety requirements, procedures etc. that can be identified during the various phases of the construction and operation of the repository. In addition, preliminary organisation and staffing plans have been drawn up, for use as the basis for planning the necessary buildings. The report gives a vision of the overall layout and function of the facility, and a proposal for the design of all individual parts of the repository. The relationships between the various parts of the repository are described, both above and below ground, as is the interplay between the part above ground and part below

  16. Deep repository for spent nuclear fuel. Facility description - Layout E. Spiral ramp with one operational area

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Stig [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Forsgren, Ebbe [SwedPower AB, Stockholm (Sweden); Lange, Fritz [Lange Art AB, Stockholm (Sweden)

    2002-04-01

    This report documents a proposal for the design of the deep repository for spent nuclear fuel. The proposal is based on the principles that were formulated in the original KBS-3 study, but has been supplemented by investigations and experience to reflect current knowledge. The purpose of the report is to provide an integrated picture of the deep repository, as a basis for SKB's other work, e.g. environmental impact assessments, transport systems, safety issues and alternative locations, and to provide a co-ordinated account of the conditions and requirements concerning all of the necessary functions in the deep repository in order to have a well functioning facility. In addition, it should be possible to use the report as: a tool in the task of achieving a co-ordinated, safe and accepted design for the facility, a basis for further planning and costing, a basis for adaptation to geographic and other conditions for the particular location, a basis for information material, both within SKB and for interested parties outside, such as public authorities, municipalities and the general public. The capacity of the deep repository has been chosen on the basis of 40 years of operation of the Swedish nuclear power reactors, which will produce approximately 9,000 tons of uranium, equivalent to approximately 4,500 canisters. The design outlined is based on theoretical analyses of functions, safety requirements, procedures etc. that can be identified during the various phases of the construction and operation of the repository. In addition, preliminary organisation and staffing plans have been drawn up, for use as the basis for planning the necessary buildings. The report gives a vision of the overall layout and function of the facility, and a proposal for the design of all individual parts of the repository. The relationships between the various parts of the repository are described, both above and below ground, as is the interplay between the part above ground and part

  17. Tools for Managing Repository Objects

    OpenAIRE

    Banker, Rajiv D.; Isakowitz, Tomas; Kauffman, Robert J.; Kumar, Rachna; Zweig, Dani

    1993-01-01

    working Paper Series: STERN IS-93-46 The past few years have seen the introduction of repository-based computer aided software engineering (CASE) tools which may finally enable us to develop software which is reliable and affordable. With the new tools come new challenges for management: Repository-based CASE changes software development to such an extent that traditional approaches to estimation, performance, and productivity assessment may no longer suffice - if they ever...

  18. Estimated transportation routes to a candidate salt repository site in Deaf Smith County, Texas

    International Nuclear Information System (INIS)

    Joy, D.S.; Johnson, P.E.

    1987-10-01

    This report presents a preliminary analysis of possible highway and rail transportation routes within Texas, Oklahoma, and New Mexico for shipments of spent fuel to the candidate repository site in Deaf Smith County, Texas. Two cases are examined for highway shipments. The initial case analyzes shipments following the Department of Transportation's HM-164 regulations for shipment of spent fuel. The second case analyzes normal commercial routes. Three rail cases are also examined. Each case analyzes potential routes that would be used based for different access spurs into the repository site. Two appendices are included which examine additional scenarios generated by restricting routes from passing through various metropolitan areas. The major finding is that most shipments to the Deaf Smith site will pass through Amarillo, Texas. There are few, if any, feasible alternative routes which would significantly reduce the amount of traffic passing through Amarillo

  19. Consideration of critically when directly disposing highly enriched spent nuclear fuel in unsaturated tuff: Bounding estimates

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P.; Tierney, M.S.; Sanchez, L.C.; Martell, M.-A.

    1996-05-01

    This report presents one of 2 approaches (bounding calculations) which were used in a 1994 study to examine the possibility of a criticality in a repository. Bounding probabilities, although rough, point to the difficulty of creating conditions under which a critical mass could be assembled (container corrosion, separation of neutron absorbers from fissile material, collapse or precipitation of fissile material) and how significant the geochemical and hydrologic phenomena are. The study could not conceive of a mechanism consistent with conditions under which an atomic explosion could occur. Should a criticality occur in or near a container in the future, boundary consequence calculations showed that fissions from one critical event (<10{sup 20} fissions, if similar to aqueous and metal accidents and experiments) are quite small compared to the amount of fissions represented by the spent fuel itself. If it is assumed that the containers necessary to hold the highly enriched spent fuel went critical once per day for 1 million years, creating an energy release of about 10{sup 20} fissions, the number of fissions equals about 10{sup 28}, which corresponds to only 1% of the fission inventory in a repository containing 70,000 metric tons of heavy metal, the expected size for the proposed repository at Yucca Mountain, Nevada.

  20. Consideration of critically when directly disposing highly enriched spent nuclear fuel in unsaturated tuff: Bounding estimates

    International Nuclear Information System (INIS)

    Rechard, R.P.; Tierney, M.S.; Sanchez, L.C.; Martell, M.-A.

    1996-05-01

    This report presents one of 2 approaches (bounding calculations) which were used in a 1994 study to examine the possibility of a criticality in a repository. Bounding probabilities, although rough, point to the difficulty of creating conditions under which a critical mass could be assembled (container corrosion, separation of neutron absorbers from fissile material, collapse or precipitation of fissile material) and how significant the geochemical and hydrologic phenomena are. The study could not conceive of a mechanism consistent with conditions under which an atomic explosion could occur. Should a criticality occur in or near a container in the future, boundary consequence calculations showed that fissions from one critical event ( 20 fissions, if similar to aqueous and metal accidents and experiments) are quite small compared to the amount of fissions represented by the spent fuel itself. If it is assumed that the containers necessary to hold the highly enriched spent fuel went critical once per day for 1 million years, creating an energy release of about 10 20 fissions, the number of fissions equals about 10 28 , which corresponds to only 1% of the fission inventory in a repository containing 70,000 metric tons of heavy metal, the expected size for the proposed repository at Yucca Mountain, Nevada

  1. Project Guarantee 1985. Radioactive wastes: Properties and allocation to final repository types

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    An overview of waste-specific data, as input into constructional engineering studies and safety analyses of Project Guarantee, is presented which describes the activity inventory of the radioactive waste to be disposed of, classified according to origin, the quantitative spezifications of the waste, the concept of classifying waste into appropriate categories, grouping into major categories and distribution of these between the different repository types, and finally, control measures which ensure observance of the specifications of the waste to be disposed of. It is expedient, for conceptional considerations and for the operational phase of the repository, to split the waste up into several suitably specified waste categories according to the practical aspects of origin and conditioning. This can be done in such a way that the waste within a specific category is sufficiently homogeneous with regard to its radiological properties and chemical composition for the requirements of safety analysis. The present volume contains base-data for around 30 waste types. Two waste types are documented with more detailed data as an example of the practicability of the comprehensive waste characterisation contained in reference report NTB 84-47. It is shown that waste-specific data which go into safety analysis and constructional engineering project studies are available in an appropriate degree of detail. The method of distributing the waste between repositories with differing degrees of protection and procedures for controlling adherence to admission specifications are developed and documented. It can be ensured that no waste with an impermissibly high radiotoxicity level will later be emplaced in a repository for low- and intermediate-level waste

  2. Establishing the concept of buffer for a high-level radioactive waste repository: An approach

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Owan; Lee, Min Soo; Choi, Heui Joo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-12-15

    The buffer is a key component of the engineered barrier system in a high-level radioactive waste (HLW) repository. The present study reviewed the requirements and functional criteria of the buffer reported in literature, and also based on the results, proposed an approach to establish a buffer concept which is applicable to an HLW repository in Korea. The hydraulic conductivity, radionuclide-retarding capacity (equilibrium distribution coefficient and diffusion coefficient), swelling pressure, thermal conductivity, mechanical properties, organic carbon content, and initialization rate were considered as major technical parameters for the functional criteria of the buffer. Domestic bentonite (Ca-bentonite) and, as an alternative, MX-80 (Na-bentonite) were proposed for the buffer of an HLW repository in Korea. The technical specifications for those proposed bentonites were set to parameter values that conservatively satisfy Korea's functional criteria for the Ca-bentonite and Swedish criteria for the Na-bentonite. The thickness of the buffer was determined by evaluating the means of shear behavior, radionuclide release, and heat conduction, which resulted in the proper buffer thickness of 0.25 to 0.5 m. However, the final thickness of the buffer should be determined by considering coupled thermal-hydraulic-mechanical evaluation and economics and engineering aspects as well.

  3. Integrating rock mechanics issues with repository design through design process principles and methodology

    International Nuclear Information System (INIS)

    Bieniawski, Z.T.

    1996-01-01

    A good designer needs not only knowledge for designing (technical know-how that is used to generate alternative design solutions) but also must have knowledge about designing (appropriate principles and systematic methodology to follow). Concepts such as open-quotes design for manufactureclose quotes or open-quotes concurrent engineeringclose quotes are widely used in the industry. In the field of rock engineering, only limited attention has been paid to the design process because design of structures in rock masses presents unique challenges to the designers as a result of the uncertainties inherent in characterization of geologic media. However, a stage has now been reached where we are be able to sufficiently characterize rock masses for engineering purposes and identify the rock mechanics issues involved but are still lacking engineering design principles and methodology to maximize our design performance. This paper discusses the principles and methodology of the engineering design process directed to integrating site characterization activities with design, construction and performance of an underground repository. Using the latest information from the Yucca Mountain Project on geology, rock mechanics and starter tunnel design, the current lack of integration is pointed out and it is shown how rock mechanics issues can be effectively interwoven with repository design through a systematic design process methodology leading to improved repository performance. In essence, the design process is seen as the use of design principles within an integrating design methodology, leading to innovative problem solving. In particular, a new concept of open-quotes Design for Constructibility and Performanceclose quotes is introduced. This is discussed with respect to ten rock mechanics issues identified for repository design and performance

  4. Experimental investigation of factors affecting the control of redox conditions within a radwaste repository

    International Nuclear Information System (INIS)

    Guppy, R.M.; Atkinson, A.

    1991-04-01

    The maximum aqueous concentration of multivalent radioelements in a radwaste repository can be estimated from the expected Eh (the oxidising or reducing tendency of the solution) and pH of the aqueous phase in the repository so long as equilibrium between all oxidising and reducing species can be guaranteed. The objective of the work reported here was to ascertain whether any significant departures from redox equilibrium are likely to arise. Technetium (VII) species were exposed under anaerobic conditions to concentrations of ferrous, hydrogen sulphide and thiosulphate species likely to be present in a repository environment to establish which species are capable of reducing aqueous Tc(VII) to a less soluble Tc(IV) solid compound. Potential catalytic solid phases and phases capable of electron exchange were also exposed to Tc(VII) species under anaerobic, aerobic and hydrogen atmospheres. We have not been able to demonstrate conclusively that mutual equilibrium was attained between technetium and iron redox couples, nor that the apparent solubility of technetium was that expected from the resulting Eh and pH of the solution, although some technetium was removed from solution. Hydrogen did not reduce Tc(VII) within the timescale of the experiments and no catalytic effects by haematite or a cementitious backfill grout for reductions involving hydrogen were observable. Magnetite removed some technetium from solution, apparently by surface reaction, under inert (argon) and reducing (hydrogen) atmospheres. Sulphides, and to a lesser extent thiosulphates, will reduce the solubility of technetium to a very low level. (author)

  5. Repository seal materials performance for a SALT Repository Project 5-year code/model development plan: Draft

    International Nuclear Information System (INIS)

    1987-06-01

    This document describes an integrated laboratory testing and model development effort for the seal system for a high-level nuclear waste repository in salt. The testing and modeling efforts are designed to determine seal material response in the repository environment, to provide models of seal system components for performance assessment, and to assist in the development of seal system designs. A code/model development and performance analysis program will be performed to predict the short- and long-term response of seal materials and seal components. The results from these analyses will be used to support the material testing activities on this contract and to support performance assessment activities that are conducted in other parts of the Salt Repository Project (SRP). 48 refs., 15 figs., 4 tabs

  6. Gas generation and release from the VLJ repository

    International Nuclear Information System (INIS)

    Vieno, T.; Valkiainen, M.

    1992-01-01

    The VLJ repository is an underground disposal facility located at the Olkiluoto nuclear power plant site on the west coast of Finland. The repository will house low (LLW) and intermediate level radioactive wastes (MLW) from the TVO I and TVO II BWR's and the spent fuel interim store at Olkiluoto. The disposal rooms have been excavated at a depth of 60... 100 meters in the crystalline bedrock. They consist of two rock silos - one for the LLW and the other for MLW. Low level waste is usually packed in steel drums and steel boxes. Medium level wastes consists of bituminized resins in steel drums. Wastes packages are emplaced in concrete boxes before transportation into the repository. Low level wastes are emplaced in the shotcreted rock silo where no backfilling will used. For medium level wastes, a separate silo of reinforced concrete has been constructed inside the rock silo. No backfilling will be used inside the concrete silo and an opening will be made in the lid of the concrete silo for gas release. The microbial degradation of low level wastes is the principle gas generation process in the repository. The gas transport though the bedrock covering the repository is evaluated with the help of ground water flow study. It is recommended that the shotcrete lining on the ceiling of the repository cavern is partly removed before the final sealing of the repository. Provided that dissipation of gases from the disposal cavern into the rock can been assured, the overall effects of gas generation on the long-term safety of the repository are insignificant. 10 refs., 6 figs

  7. Perspectives on radioactive waste repository monitoring. Confirmation, compliance, confidence building, and societal vigilance

    Energy Technology Data Exchange (ETDEWEB)

    Bergmans, Anne [Antwerp Univ. (Belgium). Research Group Society and Environment; Elam, Mark [Gothenburg Univ. (Sweden); Simmons, Peter [East Anglia Univ., Norwich (United Kingdom); Sundqvist, Goeran [Oslo Univ. (Norway)

    2012-12-15

    Monitoring is now widely seen as a necessary part of programmes for the geological disposal of radioactive waste. However, we find different perspectives on the nature and role of monitoring. Among technical experts it is viewed firstly as a matter of performance confirmation, a tool for validating the safety case underlying repository construction. Among concerned citizens we find a view of monitoring as enabling the critical scrutiny of safety, an instrument for acknowledging uncertainties and detecting emergent problems in a repository. After outlining differing views on questions of whether, why, what, where and for how long to monitor we discuss monitoring in light of constant vigilance as a technical and moral principle of nuclear safety. We suggest that ''how much monitoring'' and ''how should it be organised'' are societal questions and as such need to be broadly discussed.

  8. Post-closure radiation dose assessment for Yucca Mountain repository

    International Nuclear Information System (INIS)

    Jia Mingyan; Zhang Xiabin; Yang Chuncai

    2006-01-01

    A brief introduction of post-closure long-term radiation safety assessment results was represented for the yucca mountain high-level waste geographic disposal repository. In 1 million years after repository closure, for the higher temperature repository operating mode, the peak annual dose would be 150 millirem (120 millirem under the lower-temperature operating mode) to a reasonably maximally exposed individual approximately 18 kilometers (11 miles) from the repository. The analysis of a drilling intrusion event occurring at 30,000 years indicated a peak of the mean annual dose to the reasonably maximally exposed individual approximately 18 kilometers (11 miles) downstream of the repository would be 0.002 millirem. The analysis of an igneous activity scenario, including a volcanic eruption event and igneous intrusion event indicated a peak of the mean annual dose to the reasonably maximally exposed individual approximately 18 kilometers downstream of the repository would be 0.1 millirem. (authors)

  9. Design of repository sealing systems - 1981

    International Nuclear Information System (INIS)

    Ellison, R.D.; Shukla, D.K.; Kelsall, P.C.; D'Appolonia Consulting Engineers, Albuquerque, NM)

    1982-01-01

    Isolating nuclear waste in geologic repositories will require the sealing of penetrations such as access shafts and tunnels, disposal rooms, and exploration boreholes. This paper discusses seal designs developed for a repository in bedded salt referenced to the stratigraphy of southeastern New Mexico. Designs are based on a multiple component concept whereby individual components are designed for a specific function and location. For a repository in salt the major function of the seals is to exclude groundwater inflow. Two main types of component are included for this purpose: (1) bulk-heads are dense concrete structures keyed into the walls of the penetration and are intended to reduce flow at the interface between the seal and the salt; (2) backfills are granular materials compacted in place in the penetration. In the repository the major backfill material is crushed salt, which is expected to consolidate and recrystallize as the rooms close in response to salt creep. Densely compacted clays will be used as backfill in the shafts closer to potential sources of water inflow. 22 references, 10 figures, 1 table

  10. Creation of Data Repositories to Advance Nursing Science.

    Science.gov (United States)

    Perazzo, Joseph; Rodriguez, Margaret; Currie, Jackson; Salata, Robert; Webel, Allison R

    2017-12-01

    Data repositories are a strategy in line with precision medicine and big data initiatives, and are an efficient way to maximize data utility and form collaborative research relationships. Nurse researchers are uniquely positioned to make a valuable contribution using this strategy. The purpose of this article is to present a review of the benefits and challenges associated with developing data repositories, and to describe the process we used to develop and maintain a data repository in HIV research. Systematic planning, data collection, synthesis, and data sharing have enabled us to conduct robust cross-sectional and longitudinal analyses with more than 200 people living with HIV. Our repository building has also led to collaboration and training, both in and out of our organization. We present a pragmatic and affordable way that nurse scientists can build and maintain a data repository, helping us continue to make to our understanding of health phenomena.

  11. 21 CFR 120.8 - Hazard Analysis and Critical Control Point (HACCP) plan.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Hazard Analysis and Critical Control Point (HACCP... SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS General Provisions § 120.8 Hazard Analysis and Critical Control Point (HACCP) plan. (a) HACCP plan. Each...

  12. Building the repositories to serve

    International Nuclear Information System (INIS)

    Lersch, D.

    1994-01-01

    The project to design and build the Superconducting Super Collider (SSC) Laboratory also includes the exciting opportunity to implement client/server information systems. Lab technologists were eager to take advantage of the cost savings inherent in the open systems and a distributed, client server environment and, at the same time, conscious of the need to provide secure repositories for sensitive data as well as a schedule sensitive acquisition strategy for mission critical software. During the first year of project activity, micro-based project management and business support systems were acquired and implemented to support a small study project of less than 400 people allocating contracts of less than $1 million. The transition to modern business systems capable of supporting more than 10,000 participants (world wide) who would be researching and developing the new technologies that would support the world's largest scientific instrument, a 42 Tevatron, superconducting, super collider became a mission critical event. This paper will present the SSC Laboratory's strategy to balance its commitment to open systems, structured query language (SQL) standards and its success with acquiring commercial off the shelf software to support immediate goals. Included will be an outline of the vital roles played by other labs (Livermore, CERN, Brookhaven, Fermi and others) and a discussion of future collaboration potentials to leverage the information activities of all Department of Energy funded labs

  13. Building the repositories to serve

    International Nuclear Information System (INIS)

    Lersch, D.

    1993-04-01

    The project to design and build the Superconducting Super Collider (SSC) Laboratory also includes the exciting opportunity to implement client/server information systems. Lab technologists were eager to take advantage of the cost savings inherent in the open systems and a distributed, client server environment and, at the same time, conscious of the need to provide secure repositories for sensitive data as well as a schedule sensitive acquisition strategy for mission critical software. During the first year of project activity, micro-based project management and business support systems were acquired and implemented to support a small study project of less than 400 people allocating contracts of less than $1 million. The transition to modern business systems capable of supporting more than 10,000 participants (world wide) who would be researching and developing the new technologies that would support the world's largest scientific instrument, a 42 Tevatron, superconducting, super collider became a mission critical event. This paper will present the SSC Laboratory's strategy to balance our commitment to open systems, structured query language (SQL) standards and our success with acquiring commercial off the shelf software (COTS) to support our immediate goals. Included will be an outline of the vital roles played by other labs (Livermore, CERN, Brookhaven, Fermi and others) and a discussion of future collaboration potentials to leverage the information activities of all Department of Energy (DOE) funded labs

  14. Electronic Repositories of Marked Student Work and their Contributions to Formative Evaluation

    Directory of Open Access Journals (Sweden)

    Eva Heinrich

    2004-07-01

    Full Text Available The educational literature shows that formative assessment is highly conducive to learning. The tasks given to students in formative assessment generally require open-ended responses that can be given, for example, in essay-type format and that are assessed by a human marker. An essential component is the formative feedback provided by the marker that needs to assist the student in recognising knowledge gaps and in formulating steps to close these gaps. The concepts of ‘electronic repositories of marked student work’ introduced in this article suggests an approach to support learning from formative assessment. At the core of this concept lies the realisation that the artefacts submitted by students and assessed by markers are a valuable resource. This resource should not just be used by the submitting students but should be made accessible to future students studying the same concepts. These students can learn from the artefacts and the formative feedback attached to these artefacts. Self- and peer-assessment, important concepts closely linked to formative assessment, can be integrated with the repositories to develop the students’ subject knowledge, to enhance their critical thinking skills and to familiarise them with assessment procedures. This article develops the concepts of electronic repositories of marked student work. Special emphasis is put on reviewing the educational literature on formative assessment and on binding the concepts introduced into the literature findings.

  15. Reducing Psychological Resistance to Digital Repositories

    Directory of Open Access Journals (Sweden)

    Brian Quinn

    2010-06-01

    Full Text Available The potential value of digital repositories is dependent on the cooperation of scholars to deposit their work. Although many researchers have been resistant to submitting their work, the literature on digital repositories contains very little research on the psychology of resistance. This article looks at the psychological literature on resistance and explores what its implications might be for reducing the resistance of scholars to submitting their work to digital repositories. Psychologists have devised many potentially useful strategies for reducing resistance that might be used to address the problem; this article examines these strategies and how they might be applied.

  16. Augmenting interoperability across repositories architectural ideas

    CERN Multimedia

    CERN. Geneva

    2005-01-01

    The aDORe digital repository architecture designed and implemented by the Los Alamos Research Library is fully standards-based and highly modular, with the various components of the architecture interacting in a protocol-driven manner. Although aDORe was designed for use in the context of the Los Alamos Library, its modular and standards-based design has led to interesting insights regarding possible new levels of interoperability in a federation of heterogeneous repositories. The presentation will discuss these insights, and will illustrate that attractive federations of repositories can be built by introducing rather basic interoperability requirements. The presentation will also show that, once these requirements are met, a powerful service framework that overlays the federation can emerge.

  17. Executive-style briefings on selected repository design issues

    International Nuclear Information System (INIS)

    1978-01-01

    This document is a collection of executive-style briefings on selected repository design issues. Most of the briefings discuss differences between the US repository design bases presented in US Working Draft on Repository Physical Descriptions in a Salt Formation, prepared in support of INFCE discussions of May 1978 and the FRG-Netherlands design bases, presented in Design Study of a Radioactive Waste Repository to be Mined in a Medium-Size Salt Dome by Hamstra and Velzeboer, Netherlands Energy Research Foundation, January 1978. Advantages and disadvantages of the two sets of design bases are discussed, and the impacts of adopting either of these bases on the other's programs and positions are identified

  18. Repository-analog experiments of nuclear waste leaching and migration

    International Nuclear Information System (INIS)

    Seitz, M.G.

    1982-01-01

    The potential for radionuclide migration from a breached nuclear-waste repository depends on the leaching and subsequent interaction of the leached radionuclides with materials in the groundwater flow path. An attempt is made to consider all interactions using experiments that integrate repository materials. Results of a repository-analog experiment using borosilicate glass, fissured granite, and flowing water suggest: (1) plutonium was immobile possibly because of its low solubility; (2) caesium migrated down slowly because of sorption; and (3) neptunium remained oxidized even in water of low oxidation potential. By summing the effects of all interactions, not just sorption, the repository-analog experiment produced radionuclide migration that could be expected from a breached repository. (author)

  19. Compliance demonstration: What can be reasonably expected from safety assessment for geological repositories?

    International Nuclear Information System (INIS)

    Zuidema, P.; Smith, P.; Sumerling, T.

    1999-01-01

    When licensing a nuclear facility, it is important to demonstrate that it will comply with regulatory limits (e.g. individual dose limits) and also show that sufficient attention has been paid to optimisation of facility design and operation, such that any associated radiological impacts will be as low as reasonably achievable (ALARA). In general, in demonstrating compliance, experience can be drawn from the performance of existing and similar facilities, and monitoring plans can be specified that will confirm that actual radiological discharges during operations are within authorised limits for the facility. This is also true in respect of the operational period of a geological repository. For the post-closure phase of a repository, however, it is also necessary to show that possible releases will remain acceptably low even at long times in the future when, it is assumed, control of the facility has lapsed and there is no method of either monitoring releases or taking remedial action in the case of unexpected events or releases. In addition, within each country, a deep geological repository will be a first-of-a-kind development so that compliance arguments can be expected to be rigorously tested without any assistance from the precedent of licensing of similar facilities nationally. This puts heavy, and quite unusual, burdens on the long-term safety assessment for a geological repository to develop a case that is sufficiently strong to demonstrate compliance. This paper focuses on the problem of demonstrating compliance with long-term safety requirements for a geological repository, and explores: the overall aims and special difficulties of demonstrating compliance for a geological repository; the role of safety assessment in demonstrating compliance; the scope for optimisation of a geological repository and importance of robustness and lessons learnt from the application of safety assessment. In addition, some issues requiring further discussion and clarification

  20. Publishers and repositories

    CERN Multimedia

    CERN. Geneva

    2007-01-01

    The impact of self-archiving on journals and publishers is an important topic for all those involved in scholarly communication. There is some evidence that the physics arXiv has had no impact on physics journals, while 'economic common sense' suggests that some impact is inevitable. I shall review recent studies of librarian attitudes towards repositories and journals, and place this in the context of IOP Publishing's experiences with arXiv. I shall offer some possible reasons for the mis-match between these perspectives and then discuss how IOP has linked with arXiv and experimented with OA publishing. As well as launching OA journals we have co-operated with Cornell and the arXiv on Eprintweb.org, a platform that offers new features to repository users. View Andrew Wray's biography

  1. Business models for digital repositories

    CERN Document Server

    CERN. Geneva; Bjørnshauge, Lars

    2007-01-01

    Those setting up, or planning to set up, a digital repository may be interested to know more about what has gone before them. What is involved, what is the cost, how many people are needed, how have others made the case to their institution, and how do you get anything into it once it is built? I have recently undertaken a study of European repository business models for the DRIVER project and will present an overview of the findings.

  2. Waste package/repository impact study: Final report

    Energy Technology Data Exchange (ETDEWEB)

    1985-09-01

    The Waste Package/Repository Impact Study was conducted to evaluate the feasibility of using the current reference salt waste package in the salt repository conceptual design. All elements of the repository that may impact waste package parameters, i.e., (size, weight, heat load) were evaluated. The repository elements considered included waste hoist feasibility, transporter and emplacement machine feasibility, subsurface entry dimensions, feasibility of emplacement configuration, and temperature limits. The evaluations are discussed in detail with supplemental technical data included in Appendices to this report, as appropriate. Results and conclusions of the evaluations are discussed in light of the acceptability of the current reference waste package as the basis for salt conceptual design. Finally, recommendations are made relative to the salt project position on the application of the reference waste package as a basis for future design activities. 31 refs., 11 figs., 11 tabs.

  3. Waste package/repository impact study: Final report

    International Nuclear Information System (INIS)

    1985-09-01

    The Waste Package/Repository Impact Study was conducted to evaluate the feasibility of using the current reference salt waste package in the salt repository conceptual design. All elements of the repository that may impact waste package parameters, i.e., (size, weight, heat load) were evaluated. The repository elements considered included waste hoist feasibility, transporter and emplacement machine feasibility, subsurface entry dimensions, feasibility of emplacement configuration, and temperature limits. The evaluations are discussed in detail with supplemental technical data included in Appendices to this report, as appropriate. Results and conclusions of the evaluations are discussed in light of the acceptability of the current reference waste package as the basis for salt conceptual design. Finally, recommendations are made relative to the salt project position on the application of the reference waste package as a basis for future design activities. 31 refs., 11 figs., 11 tabs

  4. Repository exploration

    International Nuclear Information System (INIS)

    Pentz, D.L.

    1984-01-01

    This paper discusses exploration objectives and requirements for a nuclear repository in the U.S.A. The importance of designing the exploration program to meet the system performance objectives is emphasized and some examples of the extent of exploration required before the License Application for Construction Authorization is granted are also discussed

  5. Analysis of Critical Issues in Biosphere Assessment Modelling and Site Investigation

    Energy Technology Data Exchange (ETDEWEB)

    Egan, M.J.; Thorne, M.C.; Little, R.H.; Pasco, R.F. [Quintessa Limited, Henley-on-Thames (United Kingdom)

    2003-07-01

    The aim of this document is to present a critical review of issues concerned with the treatment of the biosphere and geosphere-biosphere interface in long-term performance assessment studies for nuclear waste disposal in Sweden. The review covers three main areas of investigation: a review of SKB's plans for undertaking site investigations at candidate locations for the development of a deep geological repository for spent fuel; identification of critical uncertainties associated with SKB's treatment of the geosphere-biosphere interface in recent performance assessments; and a preliminary modelling investigation of the significance of features, events and processes in the near-surface environment in terms of their effect on the accumulation and redistribution of radionuclides at the geosphere-biosphere interface. Overall, SKB's proposals for site investigations are considered to be comprehensive and, if they can be carried out to the specification presented, will constitute a benchmark that other waste management organisations will have to work hard to emulate. The main concern is that expertise for undertaking the investigations and reporting the results could be stretched very thin. The authors have also identified weaknesses in the documentation concerning the collection of evidence for environmental change and on developing scenarios for future environmental change. A fundamental assumption adopted in the renewed assessment of the SFR 1 repository, which is not discussed or justified in any of the documentation that has been reviewed, is that radionuclides enter the water column of the coastal and lake models directly, without passing first through the bed sediments. The modelling study reported herein suggests that SKB's models are robust to range of alternative conceptual descriptions relating to the geosphere-biosphere interface. There are however situations, in which contaminated groundwater is released via sediment rather than directly

  6. Analysis of Critical Issues in Biosphere Assessment Modelling and Site Investigation

    International Nuclear Information System (INIS)

    Egan, M.J.; Thorne, M.C.; Little, R.H.; Pasco, R.F.

    2003-07-01

    The aim of this document is to present a critical review of issues concerned with the treatment of the biosphere and geosphere-biosphere interface in long-term performance assessment studies for nuclear waste disposal in Sweden. The review covers three main areas of investigation: a review of SKB's plans for undertaking site investigations at candidate locations for the development of a deep geological repository for spent fuel; identification of critical uncertainties associated with SKB's treatment of the geosphere-biosphere interface in recent performance assessments; and a preliminary modelling investigation of the significance of features, events and processes in the near-surface environment in terms of their effect on the accumulation and redistribution of radionuclides at the geosphere-biosphere interface. Overall, SKB's proposals for site investigations are considered to be comprehensive and, if they can be carried out to the specification presented, will constitute a benchmark that other waste management organisations will have to work hard to emulate. The main concern is that expertise for undertaking the investigations and reporting the results could be stretched very thin. The authors have also identified weaknesses in the documentation concerning the collection of evidence for environmental change and on developing scenarios for future environmental change. A fundamental assumption adopted in the renewed assessment of the SFR 1 repository, which is not discussed or justified in any of the documentation that has been reviewed, is that radionuclides enter the water column of the coastal and lake models directly, without passing first through the bed sediments. The modelling study reported herein suggests that SKB's models are robust to range of alternative conceptual descriptions relating to the geosphere-biosphere interface. There are however situations, in which contaminated groundwater is released via sediment rather than directly to the water column

  7. Status of Proposed Repository for Latin-American Spent Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Ferrada, J.J.

    2004-10-04

    This report compiles preliminary information that supports the premise that a repository is needed in Latin America and analyzes the nuclear situation (mainly in Argentina and Brazil) in terms of nuclear capabilities, inventories, and regional spent-fuel repositories. The report is based on several sources and summarizes (1) the nuclear capabilities in Latin America and establishes the framework for the need of a permanent repository, (2) the International Atomic Energy Agency (IAEA) approach for a regional spent-fuel repository and describes the support that international institutions are lending to this issue, (3) the current situation in Argentina in order to analyze the Argentinean willingness to find a location for a deep geological repository, and (4) the issues involved in selecting a location for the repository and identifies a potential location. This report then draws conclusions based on an analysis of this information. The focus of this report is mainly on spent fuel and does not elaborate on other radiological waste sources.

  8. Design and production of the KBS-3 repository

    International Nuclear Information System (INIS)

    Moren, Lena

    2010-12-01

    The report contains the common basis for a set of Production reports, presenting how the KBS-3 repository is designed, produced and inspected. The set of reports is included in the safety report for the KBS-3 repository and repository facility. The report presents the role of the Production reports within the safety report and their common purposes and objectives. An important part of the report is to present the background and sources to the principles to be applied in the design, the functions of the KBS-3 repository and the barrier functions the engineered barriers and rock. Further, the methodology to substantiate detailed design premises for the engineered barriers, underground openings and other parts of the KBS-3 repository is presented. The report also gives an overview of the KBS-3 system and its facilities and the production lines for the spent fuel, the engineered barriers and underground openings. Finally, an introduction to quality management, safety classification and their application is given

  9. Design and production of the KBS-3 repository

    Energy Technology Data Exchange (ETDEWEB)

    Moren, Lena

    2010-12-15

    The report contains the common basis for a set of Production reports, presenting how the KBS-3 repository is designed, produced and inspected. The set of reports is included in the safety report for the KBS-3 repository and repository facility. The report presents the role of the Production reports within the safety report and their common purposes and objectives. An important part of the report is to present the background and sources to the principles to be applied in the design, the functions of the KBS-3 repository and the barrier functions the engineered barriers and rock. Further, the methodology to substantiate detailed design premises for the engineered barriers, underground openings and other parts of the KBS-3 repository is presented. The report also gives an overview of the KBS-3 system and its facilities and the production lines for the spent fuel, the engineered barriers and underground openings. Finally, an introduction to quality management, safety classification and their application is given

  10. Implementing augmentative and alternative communication in critical care settings: Perspectives of healthcare professionals.

    Science.gov (United States)

    Handberg, Charlotte; Voss, Anna Katarina

    2018-01-01

    To describe the perspectives of healthcare professionals caring for intubated patients on implementing augmentative and alternative communication (AAC) in critical care settings. Patients in critical care settings subjected to endotracheal intubation suffer from a temporary functional speech disorder and can also experience anxiety, stress and delirium, leading to longer and more complicated hospitalisation and rehabilitation. Little is known about the use of AAC in critical care settings. The design was informed by interpretive descriptive methodology along with the theoretical framework symbolic interactionism, which guided the study of healthcare professionals (n = 48) in five different intensive care units. Data were generated through participant observations and 10 focus group interviews. The findings represent an understanding of the healthcare professionals' perspectives on implementing AAC in critical care settings and revealed three themes. Caring Ontology was the foundation of the healthcare professionals' profession. Cultural Belief represented the actual premise in the interactions during the healthcare professionals' work, saving lives in a biomedical setting whilst appearing competent and efficient, leading to Triggered Conduct and giving low priority to psychosocial issues like communication. Lack of the ability to communicate puts patients at greater risk of receiving poorer treatment, which supports the pressuring need to implement and use AAC in critical care. It is documented that culture in biomedical paradigms can have consequences that are the opposite of the staffs' ideals. The findings may guide staff in implementing AAC strategies in their communication with patients and at the same time preserve their caring ontology and professional pride. Improving communication strategies may improve patient safety and make a difference in patient outcomes. Increased knowledge of and familiarity with AAC strategies may provide healthcare professionals

  11. 10 CFR 51.67 - Environmental information concerning geologic repositories.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Environmental information concerning geologic repositories... information concerning geologic repositories. (a) In lieu of an environmental report, the Department of Energy... connection with any geologic repository developed under Subtitle A of Title I, or under Title IV, of the...

  12. Conceptual design of repository facilities

    International Nuclear Information System (INIS)

    Beale, H.; Engelmann, H.J.; Souquet, G.; Mayence, M.; Hamstra, J.

    1980-01-01

    As part of the European Economic Communities programme of research into underground disposal of radioactive wastes repository design studies have been carried out for application in salt deposits, argillaceous formations and crystalline rocks. In this paper the design aspects of repositories are reviewed and conceptual designs are presented in relation to the geological formations under consideration. Emphasis has been placed on the disposal of vitrified high level radioactive wastes although consideration has been given to other categories of radioactive waste

  13. GreyGuide Forum and Repository

    OpenAIRE

    Biagioni, Stefania; Farace, Dominic

    2014-01-01

    We present the GreyGuide: an online forum and repository of good practice in the field of grey literature. The launch of the GreyGuide Repository took place in December 2013 at the Fifteenth International Conference on Grey Literature. Since then, the acquisition of both proposed and published good practices are underway. The GreyGuide as an online forum is currently in a developmental stage and is influenced by the changes that have taken place in GreyNet's new infrastructure commencing in J...

  14. Aspects of operational safety and long-term structural stability of the Morsleben repository for radioactive wastes (ERAM)

    International Nuclear Information System (INIS)

    Wernicke, R.S.

    1997-01-01

    The results of safety evaluations and safety reports reveal undoubtedly, that the Morsleben final repository operations is safe and responsible. On the basis of safety-technical evaluations some need was identified for locally optimizing the repository operations and possibly also some geotechnical features of the mine. However, this does not raise safety-related questions for man and the environment. In addition to the control exercised by the supervisory body, continuing evaluations of the repository operations assure, that changes of the safety status will be recognized in a timely manner and that competent action may be taken if necessary. (orig.) [de

  15. Optimized application of systems engineering to nuclear waste repository projects

    International Nuclear Information System (INIS)

    Miskimin, P.A.; Shepard, M.

    1986-01-01

    The purpose of this presentation is to describe a fully optimized application of systems engineering methods and philosophy to the management of a large nuclear waste repository project. Knowledge gained from actual experience with the use of the systems approach on two repository projects is incorporated in the material presented. The projects are currently evaluating the isolation performance of different geologic settings and are in different phases of maturity. Systems engineering methods were applied by the principal author at the Waste Isolation Pilot Plant (WIPP) in the form of a functional analysis. At the Basalt Waste Isolation Project (BWIP), the authors assisted the intergrating contractor with the development and application of systems engineering methods. Based on this experience and that acquired from other waste management projects, an optimized plan for applying systems engineering techniques was developed. The plan encompasses the following aspects: project organization, developing and defining requirements, assigning work responsibilities, evaluating system performance, quality assurance, controlling changes, enhancing licensability, optimizing project performance, and addressing regulatory issues. This information is presented in the form of a roadmap for the practical application of system engineering principles to a nuclear waste repository project

  16. Training courses on integrated safety assessment modelling for waste repositories

    International Nuclear Information System (INIS)

    Mallants, D.

    2007-01-01

    Near-surface or deep repositories of radioactive waste are being developed and evaluated all over the world. Also, existing repositories for low- and intermediate-level waste often need to be re-evaluated to extend their license or to obtain permission for final closure. The evaluation encompasses both a technical feasibility as well as a safety analysis. The long term safety is usually demonstrated by means of performance or safety assessment. For this purpose computer models are used that calculate the migration of radionuclides from the conditioned radioactive waste, through engineered barriers to the environment (groundwater, surface water, and biosphere). Integrated safety assessment modelling addresses all relevant radionuclide pathways from source to receptor (man), using in combination various computer codes in which the most relevant physical, chemical, mechanical, or even microbiological processes are mathematically described. SCK-CEN organizes training courses in Integrated safety assessment modelling that are intended for individuals who have either a controlling or supervising role within the national radwaste agencies or regulating authorities, or for technical experts that carry out the actual post-closure safety assessment for an existing or new repository. Courses are organised by the Department of Waste and Disposal

  17. Ventilation System Strategy for a Prospective Korean Radioactive Waste Repository

    International Nuclear Information System (INIS)

    Kim, Jin; Kwon, Sang Ki

    2005-01-01

    In the stage of conceptual design for the construction and operation of the geologic repository for radioactive wastes, it is important to consider a repository ventilation system which serves the repository working environment, hygiene and safety of the public at large, and will allow safe maintenance like moisture content elimination in repository for the duration of the repositories life, construction/operation/closure, also allowing safe waste transportation and emplacement. This paper describes the possible ventilation system design criteria and requirements for the prospective Korean radioactive waste repositories with emphasis on the underground rock cavity disposal method in the both cases of low and medium-level and high-level wastes. It was found that the most important concept is separate ventilation systems for the construction (development) and waste emplacement (storage) activities. In addition, ventilation network system modeling, natural ventilation, ventilation monitoring systems and real time ventilation simulation, and fire simulation and emergency system in the repository are briefly discussed.

  18. Types of safety assessments of near surface repository for radioactive waste

    International Nuclear Information System (INIS)

    Mateeva, M.

    2004-01-01

    The purpose of this article is to presents the classification of different types safety assessments of near surface repository for low and intermediate level radioactive waste substantiated with results of safety assessments generated in Bulgaria. The different approach of safety assessments applied for old existing repository as well as for site selection for construction new repository is outlined. The regulatory requirements in Bulgaria define three main types of assessments: Safety assessment; Technical substation of repository safety; Assessment of repository influence on environment that is in form of report prepared from the Ministry of environment and waters on the base of results obtained in two first types of assessments. Additionally first type is subdivided in three categories - preliminary safety assessment, safety assessment and post closure safety assessment, which are generated using deterministic approach. The technical substation of repository safety is generated using probabilistic approach. Safety assessment results that are presented here are based on evaluation of existing old repository type 'Radon' in Novi Han and real site selection procedure for new near surface repository for low and intermediate level radioactive waste from nuclear power station in Kozloduy. The important role of safety assessment for improvement the repository safety as well as for repository licensing, correct site selection and right choice of engineer barriers and repository design is discussed using generated results. (author)

  19. MODELING OF THE GROUNDWATER TRANSPORT AROUND A DEEP BOREHOLE NUCLEAR WASTE REPOSITORY

    Energy Technology Data Exchange (ETDEWEB)

    N. Lubchenko; M. Rodríguez-Buño; E.A. Bates; R. Podgorney; E. Baglietto; J. Buongiorno; M.J. Driscoll

    2015-04-01

    The concept of disposal of high-level nuclear waste in deep boreholes drilled into crystalline bedrock is gaining renewed interest and consideration as a viable mined repository alternative. A large amount of work on conceptual borehole design and preliminary performance assessment has been performed by researchers at MIT, Sandia National Laboratories, SKB (Sweden), and others. Much of this work relied on analytical derivations or, in a few cases, on weakly coupled models of heat, water, and radionuclide transport in the rock. Detailed numerical models are necessary to account for the large heterogeneity of properties (e.g., permeability and salinity vs. depth, diffusion coefficients, etc.) that would be observed at potential borehole disposal sites. A derivation of the FALCON code (Fracturing And Liquid CONvection) was used for the thermal-hydrologic modeling. This code solves the transport equations in porous media in a fully coupled way. The application leverages the flexibility and strengths of the MOOSE framework, developed by Idaho National Laboratory. The current version simulates heat, fluid, and chemical species transport in a fully coupled way allowing the rigorous evaluation of candidate repository site performance. This paper mostly focuses on the modeling of a deep borehole repository under realistic conditions, including modeling of a finite array of boreholes surrounded by undisturbed rock. The decay heat generated by the canisters diffuses into the host rock. Water heating can potentially lead to convection on the scale of thousands of years after the emplacement of the fuel. This convection is tightly coupled to the transport of the dissolved salt, which can suppress convection and reduce the release of the radioactive materials to the aquifer. The purpose of this work has been to evaluate the importance of the borehole array spacing and find the conditions under which convective transport can be ruled out as a radionuclide transport mechanism

  20. Data Stewardship: Environmental Data Curation and a Web-of-Repositories

    Directory of Open Access Journals (Sweden)

    Karen S. Baker

    2009-10-01

    Full Text Available Scientific researchers today frequently package measurements and associated metadata as digital datasets in anticipation of storage in data repositories. Through the lens of environmental data stewardship, we consider the data repository as an organizational element central to data curation. One aspect of non-commercial repositories, their distance-from-origin of the data, is explored in terms of near and remote categories. Three idealized repository types are distinguished – local, center, and archive - paralleling research, resource, and reference collection categories respectively. Repository type characteristics such as scope, structure, and goals are discussed. Repository similarities in terms of roles, activities and responsibilities are also examined. Data stewardship is related to care of research data and responsible scientific communication supported by an infrastructure that coordinates curation activities; data curation is defined as a set of repeated and repeatable activities focusing on tending data and creating data products within a particular arena. The concept of “sphere-of-context” is introduced as an aid to distinguishing repository types. Conceptualizing a “web-of-repositories” accommodates a variety of repository types and represents an ecologically inclusive approach to data curation.

  1. A free-piston Stirling engine/linear alternator controls and load interaction test facility

    Science.gov (United States)

    Rauch, Jeffrey S.; Kankam, M. David; Santiago, Walter; Madi, Frank J.

    1992-01-01

    A test facility at LeRC was assembled for evaluating free-piston Stirling engine/linear alternator control options, and interaction with various electrical loads. This facility is based on a 'SPIKE' engine/alternator. The engine/alternator, a multi-purpose load system, a digital computer based load and facility control, and a data acquisition system with both steady-periodic and transient capability are described. Preliminary steady-periodic results are included for several operating modes of a digital AC parasitic load control. Preliminary results on the transient response to switching a resistive AC user load are discussed.

  2. The environmental constraint needs for design improvements to the Saligny I/LLW-repository near Cernavoda NPP

    International Nuclear Information System (INIS)

    Barariu, Gheorghe

    2007-01-01

    The paper presents the new perspectives on the development of the L/ILW Final Repository Project which will be built near Cernavoda NPP. The Repository is designed to satisfy the main performance objectives in accordance to IAEA recommendation. Starting in October 1996, Romania became a country with an operating nuclear power plant. Reactor 2 reached the criticality on May 6, 2007 and it will be put in commercial operation in September 2007. The Ministry of Economy and Finance has decided to proceed with the commissioning of Units 3 and 4 of Cernavoda NPP till 2014. The Strategy for radioactive waste management was elaborated by National Agency for Radioactive Waste (ANDRAD), the jurisdictional authority for definitive disposal and the coordination of nuclear spent fuel and radioactive waste management (Order 844/2004) with attributions established by Governmental Decision (GO) 31/2006. The Strategy specifies the commissioning of the Saligny L/IL Radwaste Repository near Cernavoda NPP in 2014. When designing the L/IL Radwaste Repository, the following prerequisites have been taken into account: 1) Cernavoda NPP will be equipped with 4 Candu 6 units. 2) National Legislation in radwaste management will be reviewed and/or completed to harmonize with UE standards 3) The selected site is now in process of confirmation after a comprehensive set of interdisciplinary investigations. (author)

  3. Harvesting NASA's Common Metadata Repository

    Science.gov (United States)

    Shum, D.; Mitchell, A. E.; Durbin, C.; Norton, J.

    2017-12-01

    As part of NASA's Earth Observing System Data and Information System (EOSDIS), the Common Metadata Repository (CMR) stores metadata for over 30,000 datasets from both NASA and international providers along with over 300M granules. This metadata enables sub-second discovery and facilitates data access. While the CMR offers a robust temporal, spatial and keyword search functionality to the general public and international community, it is sometimes more desirable for international partners to harvest the CMR metadata and merge the CMR metadata into a partner's existing metadata repository. This poster will focus on best practices to follow when harvesting CMR metadata to ensure that any changes made to the CMR can also be updated in a partner's own repository. Additionally, since each partner has distinct metadata formats they are able to consume, the best practices will also include guidance on retrieving the metadata in the desired metadata format using CMR's Unified Metadata Model translation software.

  4. Development of an Alternative Glass Formulation for Vitrification of Excess Plutonium

    International Nuclear Information System (INIS)

    MARRA, JAMES

    2006-01-01

    compositional region of potential glass-in-glass phase separation toward a region near a low melting eutectic trough. The resulting LaBS Frit X composition was fabricated and tested. The chemical durability of the LaBS Frit X glass was shown to be equivalent to the reference Frit B composition as measured by the Product Consistency Test (PCT). The Frit X composition demonstrated improved component solubility in surrogate and plutonium testing. This composition also exhibited improved devitrification behavior that could translate to lower glass processing temperatures and minimize any negative impacts on glass pouring. Testing with the LaBS Frit X composition also indicated the potential to intentionally precipitate a PuO 2 -HfO 2 solid solution phase. This could result in a means to dramatically improve the plutonium leach performance in the repository by the formation of a highly insoluble phase with an inherent neutron absorber. Preliminary testing indicated that glass heat treatment could be used to intentionally form this phase in the glass. This study identified an alternative LaBS glass composition (Frit X) that should be tested further. Specifically, the suite of performance tests currently being conducted on the reference Frit B composition should be conducted on the Frit X composition to provide the necessary data for repository modeling. The potential to form a PuO 2 -HfO 2 phase in the glass should also be further pursued as a potential means to improve waste form performance and criticality control. Additionally, as the feed stream chemistry destined for disposition via vitrification is better defined, a thorough glass formulation variability study should be performed to demonstrate that feed variations can be accommodated in the glass. Finally, this composition should be utilized in melter testing to support project design initiatives

  5. Groundwater salinity at Olkiluoto and its effects on a spent fuel repository

    Energy Technology Data Exchange (ETDEWEB)

    Vieno, T. [VTT Energy, Espoo (Finland)

    2000-06-01

    significantly decrease the swelling pressure and increase the hydraulic conductivity of such a backfill. The most promising alternative backfill options are natural mixed-layer clay (Friedland clay) and crushed rock backfill combined with special sealing structures. It is recommended that for a repository to be constructed at the depth of about 500 metres at Olkiluoto, all engineered barriers should be designed to perform properly at groundwater salinities ranging from fresh water to 35 g/l. Geochemistry and salinity of groundwater will be a key area in the further characterisation of Olkiluoto, in supporting research, as well as in performance assessment. Posiva will participate in studies and large-scale experiments on the performance of bentonite-based as well as alternative backfill and buffer materials in the projects to be launched within the 5th Framework Programme of the European Commission and in the Prototype Repository in the Hard Rock Laboratory at Aespoe. (orig.)

  6. Core Certification of Data Repositories: Trustworthiness and Long-Term Stewardship

    Science.gov (United States)

    de Sherbinin, A. M.; Mokrane, M.; Hugo, W.; Sorvari, S.; Harrison, S.

    2017-12-01

    Scientific integrity and norms dictate that data created and used by scientists should be managed, curated, and archived in trustworthy data repositories thus ensuring that science is verifiable and reproducible while preserving the initial investment in collecting data. Research stakeholders including researchers, science funders, librarians, and publishers must also be able to establish the trustworthiness of data repositories they use to confirm that the data they submit and use remain useful and meaningful in the long term. Data repositories are increasingly recognized as a key element of the global research infrastructure and the importance of establishing their trustworthiness is recognised as a prerequisite for efficient scientific research and data sharing. The Core Trustworthy Data Repository Requirements are a set of universal requirements for certification of data repositories at the core level (see: https://goo.gl/PYsygW). They were developed by the ICSU World Data System (WDS: www.icsu-wds.org) and the Data Seal of Approval (DSA: www.datasealofapproval.org)—the two authoritative organizations responsible for the development and implementation of this standard to be further developed under the CoreTrustSeal branding . CoreTrustSeal certification of data repositories involves a minimally intensive process whereby repositories supply evidence that they are sustainable and trustworthy. Repositories conduct a self-assessment which is then reviewed by community peers. Based on this review CoreTrustSeal certification is granted by the CoreTrustSeal Standards and Certification Board. Certification helps data communities—producers, repositories, and consumers—to improve the quality and transparency of their processes, and to increase awareness of and compliance with established standards. This presentation will introduce the CoreTrustSeal certification requirements for repositories and offer an opportunity to discuss ways to improve the contribution of

  7. United States Crystalline Repository Project - key research areas

    International Nuclear Information System (INIS)

    Patera, E.S.

    1986-01-01

    The Crystalline Repository Project is responsible for siting the second high-level nuclear waste repository in crystalline rock for the US Department of Energy. A methodology is being developed to define data and information needs and a way to evaluate that information. The areas of research the Crystalline Repository Project is involved in include fluid flow in a fractured network, coupled thermal, chemical and flow processes and cooperation in other nations and OECD research programs

  8. Towards Content Development For Institutional Digital Repository ...

    African Journals Online (AJOL)

    The growth in Information and Communication Technology has lead to the emergence of Institutional Digital Repository, a digital archive for the preservation and dissemination of institutional research outputs. Institutional Digital Repositories make possible global dissemination of research outputs through the use of the ...

  9. SR 97. Alternative models project. Stochastic continuum modelling of Aberg

    International Nuclear Information System (INIS)

    Widen, H.; Walker, D.

    1999-08-01

    As part of studies into the siting of a deep repository for nuclear waste, Swedish Nuclear Fuel and Waste Management Company (SKB) has commissioned the Alternative Models Project (AMP). The AMP is a comparison of three alternative modelling approaches to bedrock performance assessment for a single hypothetical repository, arbitrarily named Aberg. The Aberg repository will adopt input parameters from the Aespoe Hard Rock Laboratory in southern Sweden. The models are restricted to an explicit domain, boundary conditions and canister location to facilitate the comparison. The boundary conditions are based on the regional groundwater model provided in digital format. This study is the application of HYDRASTAR, a stochastic continuum groundwater flow and transport-modelling program. The study uses 34 realisations of 945 canister locations in the hypothetical repository to evaluate the uncertainty of the advective travel time, canister flux (Darcy velocity at a canister) and F-ratio. Several comparisons of variability are constructed between individual canister locations and individual realisations. For the ensemble of all realisations with all canister locations, the study found a median travel time of 27 years, a median canister flux of 7.1 x 10 -4 m/yr and a median F-ratio of 3.3 x 10 5 yr/m. The overall pattern of regional flow is preserved in the site-scale model, as is reflected in flow paths and exit locations. The site-scale model slightly over-predicts the boundary fluxes from the single realisation of the regional model. The explicitly prescribed domain was seen to be slightly restrictive, with 6% of the stream tubes failing to exit the upper surface of the model. Sensitivity analysis and calibration are suggested as possible extensions of the modelling study

  10. Groundwater flow modelling of an abandoned partially open repository

    Energy Technology Data Exchange (ETDEWEB)

    Bockgaard, Niclas (Golder Associates AB (Sweden))

    2010-12-15

    As a part of the license application, according to the nuclear activities act, for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. The modelling study presented here serves as an input for analyses of so-called future human actions that may affect the repository. The objective of the work was to investigate the hydraulic influence of an abandoned partially open repository. The intention was to illustrate a pessimistic scenario of the effect of open tunnels in comparison to the reference closure of the repository. The effects of open tunnels were studied for two situations with different boundary conditions: A 'temperate' case with present-day boundary conditions and a generic future 'glacial' case with an ice sheet covering the repository. The results were summarized in the form of analyses of flow in and out from open tunnels, the effect on hydraulic head and flow in the surrounding rock volume, and transport performance measures of flow paths from the repository to surface

  11. Groundwater flow modelling of an abandoned partially open repository

    International Nuclear Information System (INIS)

    Bockgaard, Niclas

    2010-12-01

    As a part of the license application, according to the nuclear activities act, for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. The modelling study presented here serves as an input for analyses of so-called future human actions that may affect the repository. The objective of the work was to investigate the hydraulic influence of an abandoned partially open repository. The intention was to illustrate a pessimistic scenario of the effect of open tunnels in comparison to the reference closure of the repository. The effects of open tunnels were studied for two situations with different boundary conditions: A 'temperate' case with present-day boundary conditions and a generic future 'glacial' case with an ice sheet covering the repository. The results were summarized in the form of analyses of flow in and out from open tunnels, the effect on hydraulic head and flow in the surrounding rock volume, and transport performance measures of flow paths from the repository to surface

  12. Current Status of Deep Geological Repository Development

    International Nuclear Information System (INIS)

    Budnitz, R J

    2005-01-01

    This talk provided an overview of the current status of deep-geological-repository development worldwide. Its principal observation is that a broad consensus exists internationally that deep-geological disposal is the only long-term solution for disposition of highly radioactive nuclear waste. Also, it is now clear that the institutional and political aspects are as important as the technical aspects in achieving overall progress. Different nations have taken different approaches to overall management of their highly radioactive wastes. Some have begun active programs to develop a deep repository for permanent disposal: the most active such programs are in the United States, Sweden, and Finland. Other countries (including France and Russia) are still deciding on whether to proceed quickly to develop such a repository, while still others (including the UK, China, Japan) have affirmatively decided to delay repository development for a long time, typically for a generation of two. In recent years, a major conclusion has been reached around the world that there is very high confidence that deep repositories can be built, operated, and closed safely and can meet whatever safety requirements are imposed by the regulatory agencies. This confidence, which has emerged in the last few years, is based on extensive work around the world in understanding how repositories behave, including both the engineering aspects and the natural-setting aspects, and how they interact together. The construction of repositories is now understood to be technically feasible, and no major barriers have been identified that would stand in the way of a successful project. Another major conclusion around the world is that the overall cost of a deep repository is not as high as some had predicted or feared. While the actual cost will not be known in detail until the costs are incurred, the general consensus is that the total life-cycle cost will not exceed a few percent of the value of the

  13. CRITICALITY CONTROL DURING THE DISMANTLING OF A URANIUM CONVERSION PLANT

    International Nuclear Information System (INIS)

    LADURELLE, Laurent; LISBONNE, Pierre

    2003-01-01

    Within the Commissariat a l'Energie Atomique, in the Cadarache Research Center in southern France, the production at the Enriched Uranium Treatment Workshops started in 1965 and ended in 1995. The dismantling is in progress and will last until 2006. The decommissioning is planned in 2007. Since the authorized enrichment in 235U was 10% in some parts of the plant, and unlimited in others, the equipment and procedures were designed for criticality control during the operating period. Despite the best previous removing of the uranium in the inner parts of the equipment, evaluation of the mass of remaining fissile material by in site gamma spectrometry measurement shows that the safety of the ''clean up'' operations requires specific criticality control procedures, this mass being higher than the safe mass. The chosen method is therefore based on the mapping of fissile material in the contaminated parts of the equipment and on the respect of particular rules set for meeting the criticality control standards through mass control. The process equipment is partitioned in separated campaign, and for each campaign the equipment dismantling is conducted with a precise traceability of the pieces, from the equipment to the drum of waste, and the best final evaluation of the mass of fissile material in the drum. The first results show that the mass of uranium found in the dismantled equipment is less than the previous evaluation, and they enable us to confirm that the criticality was safely controlled during the operations. The mass of fissile material remaining in the equipment can be then carefully calculated, when it is lower than the minimal critical mass, and on the basis of a safety analysis, we will be free of any constraints regarding criticality control, this allowing to make procedures easier, and to speed up the operations

  14. Earthquakes - a danger to deep-lying repositories?

    International Nuclear Information System (INIS)

    2012-03-01

    This booklet issued by the Swiss National Cooperative for the Disposal of Radioactive Waste NAGRA takes a look at geological factors concerning earthquakes and the safety of deep-lying repositories for nuclear waste. The geological processes involved in the occurrence of earthquakes are briefly looked at and the definitions for magnitude and intensity of earthquakes are discussed. Examples of damage caused by earthquakes are given. The earthquake situation in Switzerland is looked at and the effects of earthquakes on sub-surface structures and deep-lying repositories are discussed. Finally, the ideas proposed for deep-lying geological repositories for nuclear wastes are discussed

  15. Stream-simulation experiments for waste-repository investigations

    International Nuclear Information System (INIS)

    Seitz, M.G.

    1980-01-01

    The potential for radionuclide migration by groundwater flow from a breached-water repository depends on the leaching process and on chemical changes that might occur as the radionuclide moves away from the repository. Therefore, migration involves the interactions of leached species with (1) the waste and canister, (2) the engineered barrier, and (3) the geologic materials surrounding the repository. Rather than attempt to synthesize each species and study it individually, another approach is to integrate all species and interactions using stream-simulation experiments. Interactions identified in these studies can then be investigated in detail in simpler experiments

  16. The function of packing materials in a high-level nuclear waste repository and some candidate materials: Salt Repository Project

    International Nuclear Information System (INIS)

    Bunnell, L.R.; Shade, J.W.

    1987-03-01

    Packing materials should be included in waste package design for a high-level nuclear waste repository in salt. A packing material barrier would increase confidence in the waste package by alleviating possible shortcomings in the present design and prolonging confinement capabilities. Packing materials have been studied for uses in other geologic repositories; appropriately chosen, they would enhance the confinement capabilities of salt repository waste packages in several ways. Benefits of packing materials include retarding or chemically modifying brines to reduce corrosion of the waste package, providing good thermal conductivity between the waste package and host rock, retarding or absorbing radionuclides, and reducing the massiveness of the waste package. These benefits are available at low percentage of total repository cost, if the packing material is properly chosen and used. Several candidate materials are being considered, including oxides, hydroxides, silicates, cement-based mixtures, and clay mixtures. 18 refs

  17. Management and Operational Control of Criticality

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, J. T. [Authority Health and Safety Branch, United Kingdom Atomic Energy Authority, Risley, Lancs. (United Kingdom)

    1966-05-15

    The evidence of the six process criticality accidents that have been reported to date shows that, without exception, they have been due to the failure of operational controls. In no instance has a criticality accident in processing been due to the use of wrong data 01 inaccurate calculation. Criticality accidents are least likely to occur in the production stream and are more likely to be associated with ancillary equipment and operations. Important as correct criticality calculations are, there are many other considerations which require the exercise of judgement in establishing the operational environment. No operation involving fissile material should be permitted without a formal review resulting in a documented statement of (a) the environmental assessment, (b) the nuclear safety arguments which demonstrate safety under that environment, and (c) the operational requirements which will ensure the validity of (b) under the conditions of (a). To ensure the continued viability of the environmental assessment and the continued reliability of clearance conditions there should be close supervision by operating management, and periodic checks made by site nuclear safety staff. Additionally, there should be periodic and systematic examinations by competent persons who are not responsible to the overall management of the site. (author)

  18. Salt Repository Project waste emplacement mode decision paper: Revison 1

    International Nuclear Information System (INIS)

    1987-08-01

    This paper provides a recommendation as to the mode of waste emplacement to be used as the current basis for site characterization activity for the Deaf Smith County, Texas, high level nuclear waste repository site. It also presents a plan for implementing the recommendation so as to provide a high level of confidence in the project's success. Since evaluations of high-level waste disposal in geologic repositories began in the 1950s, most studies emplacement in salt formations employed the vertical orientation for emplacing waste packages in boreholes in the floor of the underground facility. This orientation was used in trials at Project Salt Vault in the 1960s. The Waste Isolation Pilot Plant (WIPP) has recently settled on a combination of vertical and horizontal modes for various waste types. This paper analyzes the information available and develops a project position upon which to base current site characterization activities. The position recommended is that the SRP should continue to use the vertical waste emplacement mode as the reference design and to carry the horizontal mode as a ''passive'' alternative. This position was developed based upon the conclusions of a decision analysis, risk assessment, and cost/schedule impact assessment. 52 refs., 6 figs., 1 tab

  19. Representation of an open repository in groundwater flow models

    International Nuclear Information System (INIS)

    Painter, Scott; Sun, Alexander

    2005-08-01

    The effect of repository tunnels on groundwater flow has been identified as a potential issue for the nuclear waste repository being considered by SKB for a fractured granite formation in Sweden. In particular, the following pre-closure and post-closure processes have been identified as being important: inflows into open tunnels as functions of estimated grouting efficiencies, drawdown of the water table in the vicinity of the repository, upcoming of saline water, 'turnover' of surface water in the upper bedrock, and resaturation of backfilled tunnels following repository closure. The representation of repository tunnels within groundwater models is addressed in this report. The primary focus is on far-field flow that is modeled with a continuum porous medium approximation. Of particular interest are the consequences of the tunnel representation on the transient response of the groundwater system to repository operations and repository closure, as well as modeling issues such as how the water-table free surface and the coupling to near-surface hydrogeology should be handled. The overall objectives are to understand the consequences of current representations and to identify appropriate approximations for representing open tunnels in future groundwater modeling studies. The following conclusions can be drawn from the results of the simulations: 1. Two-phase flow may be induced in the vicinity of repository tunnels during repository pre-closure operations, but the formation of a two-phase flow region will not significantly affect far-field flow or inflows into tunnels. 2. The water table will be drawn down to the repository horizon and tunnel inflows will reach a steady-state value within about 5 years. 3. Steady-state inflows at the repository edge are estimated to be about 250 m 3 /year per meter of tunnel. Inflows will be greater during the transient de-watering period and less for tunnel locations closer to the repository center. 4. Significant amounts of water

  20. Representation of an open repository in groundwater flow models

    Energy Technology Data Exchange (ETDEWEB)

    Painter, Scott; Sun, Alexander [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

    2005-08-01

    The effect of repository tunnels on groundwater flow has been identified as a potential issue for the nuclear waste repository being considered by SKB for a fractured granite formation in Sweden. In particular, the following pre-closure and post-closure processes have been identified as being important: inflows into open tunnels as functions of estimated grouting efficiencies, drawdown of the water table in the vicinity of the repository, upcoming of saline water, 'turnover' of surface water in the upper bedrock, and resaturation of backfilled tunnels following repository closure. The representation of repository tunnels within groundwater models is addressed in this report. The primary focus is on far-field flow that is modeled with a continuum porous medium approximation. Of particular interest are the consequences of the tunnel representation on the transient response of the groundwater system to repository operations and repository closure, as well as modeling issues such as how the water-table free surface and the coupling to near-surface hydrogeology should be handled. The overall objectives are to understand the consequences of current representations and to identify appropriate approximations for representing open tunnels in future groundwater modeling studies. The following conclusions can be drawn from the results of the simulations: 1. Two-phase flow may be induced in the vicinity of repository tunnels during repository pre-closure operations, but the formation of a two-phase flow region will not significantly affect far-field flow or inflows into tunnels. 2. The water table will be drawn down to the repository horizon and tunnel inflows will reach a steady-state value within about 5 years. 3. Steady-state inflows at the repository edge are estimated to be about 250 m{sup 3}/year per meter of tunnel. Inflows will be greater during the transient de-watering period and less for tunnel locations closer to the repository center. 4. Significant

  1. Comparisons of alternative sites for the encapsulation plant

    International Nuclear Information System (INIS)

    Havel, R.

    2000-12-01

    This report discuses the pros and cons of localizing the spent fuel encapsulation plant at the planned Swedish repository for spent nuclear fuel or at CLAB (Central interim storage facility for spent nuclear fuel). After weighing together all aspects (economy, technology, safety, transports, personnel and environment) it is concluded that building the encapsulation plant in direct connection to CLAB is the most advantageous alternative

  2. The industrial organization of the repository. Pitfall or logical?

    International Nuclear Information System (INIS)

    Frostenson, Magnus

    2010-11-01

    From a systems perspective the organization of the Swedish final repository project for nuclear waste is studied. Different aspects of organization are identified in the report, covering dimensions of geographical, operative, structural, responsibility and contextual organization. Following SKB's site selection for the applications for the final repository for spent nuclear system and the closing of the surplus value agreement, issues concerning operative, structural and contextual organization tend to become particularly pressing, which is reflected in three research questions: - How will the final repository project be organized operatively and structurally over time? - Why is the final repository project organized in this way by SKB? - What kind of contextual organization takes place in the final repository project and what are the consequences of these activities? How the different industrial units of the final repository project should be run and within which structure, for example concerning ownership and integration of units, is established in the report. SKB's reasons for choosing this kind of organization are also highlighted. Apart from legal and safety-related demands that must be met together with the demands of the owners, SKB's strategic preference for insourcing conditions organizational choices. The traditional task centred operative and structural organization of SKB is also reflected in the organizational choices for the present and future units of the final depository system. Contextual organization implies deepened actor relationships between SKB's owners and SKB on the one side and the municipalities Oesthammar and Oskarshamn on the other. Through active organizing, the final repository arena 'narrows down' and the final repository issue turns into an in many respects local issue. There is a clear tendency that the roles of SKB are multiplied in order to handle the demands that central stakeholders - in particular the municipalities - place on

  3. The geochemical immobilization of uranium in a spent fuel repository in the Canadian Shield: Evidence from natural analogue investigations

    International Nuclear Information System (INIS)

    Bottomley, D.J.

    1996-04-01

    Natural analogue studies of uranium ore deposits provide valuable information on the geochemical conditions that control the mobilization of uranium and associated radionuclides in groundwaters. At Cigar Lake in northern Saskatchewan, the Pocos de Caldas site in Brazil, and at Palmottu in Finland, groundwaters are sufficiently reducing to prevent significant oxidation of U +4 to the more soluble U +6 oxidation state. Despite being one of the richest uranium deposits in the world, uranium concentrations in the groundwaters around the Cigar Lake ore are less than 5 x 10 -8 M. Even under oxiding conditions uranium may not necessarily be highly mobilized by groundwaters. Studies of the relatively shallow uranium ore deposits in the Alligator Rivers region of Australia have shown that uranium transport by groundwater can be limited because of uranium sorption onto secondary iron oxides within the aquifer. However, studies at 'negative analgoue' sites indicate that where the host rocks contain low concentrations of reductants such as iron sulphides, strongly reducing conditions are not established and high concentrations of dissolved uranium can result, even in areas where uranium ore deposits are not known to occur. The release rate of radionuclides from a spent fuel repository will be strongly dependent on the redox conditions that are established following resaturation of the repository. Groundwater at depths of 500 m in a granitic pluton may not be sufficiently reducing to prevent oxidative dissolution of uranium or oxidation of associated radionuclides such as 99 Tc. Accordingly other shield rocks richer in reductants, such as greenstone belts, should be considered as potential host rocks for a repository or the repository should be constructed at depths closer to 1000 m in granitic rock where more reducing conditions are likely to prevail. Alternatively, addition of reductants to the waste containers may be feasible as a means of maintaining reducing conditions

  4. Transfer systems in an underground repository

    International Nuclear Information System (INIS)

    Berg, H.P.; Ehrlich, D.

    1991-01-01

    In addition to logistic problem definitions taking into account the waste types of the wastes to be disposed of and the mining conditions, transport and handling of radioactive wastes in a repository, particularly require the keeping of safety technological marginal conditions mainly resulting from the accident analyses carried out. The realization of these safety technological aspects is described taking the planned Konrad repository as an example. (author)

  5. Asset Reuse of Images from a Repository

    Science.gov (United States)

    Herman, Deirdre

    2014-01-01

    According to Markus's theory of reuse, when digital repositories are deployed to collect and distribute organizational assets, they supposedly help ensure accountability, extend information exchange, and improve productivity. Such repositories require a large investment due to the continuing costs of hardware, software, user licenses, training,…

  6. Classifying decommissioning wastes for allocation to appropriate final repositories

    International Nuclear Information System (INIS)

    Alder, J.C.; Tunaboylu, K.

    1982-01-01

    For the safe disposal of radioactive wastes in different repositories, it is of advantage to classify them in well-defined conditioned categories, appropriate for final disposal. These categories, the so-called waste sorts are characterized by similar radionuclide distribution, similar nuclide-specific activity concentrations and similar waste matrix. A methodology is presented for classifying decommissioning wastes and is applied to the decommissioning wastes arising from a Swiss program of 6 GWe. The amounts and nuclide-specific activity inventories of the decommissioning waste sorts have been estimated. A first allocation into two different repository types has been performed. Such a classification enables one to define the source parameters for repository safety analysis and allows one to allocate the different waste categories into appropriate final repositories. This work presents a first iteration to determine which waste sorts belong to which repository type. The characteristics of waste sorts have to be better defined and the protective strength of the repository barriers has to be optimized. 7 references, 2 figures, 4 tables

  7. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 2. Commercial waste forms, packaging and projections for preconceptual repository design studies

    International Nuclear Information System (INIS)

    1978-04-01

    This volume, Y/OWI/TM-36/2, ''Commercial Waste Forms, Packaging and Projections for Preconceptual Repository Design Studies,'' is one of a 23-volume series, ''Technical Support for GEIS: Radioactive Waste Isolation in Geologic Formations,'' Y/OWI/TM-36, which supplements the ''Contribution to Draft Generic Environmental Impact Statement on Commercial Waste Management: Radioactive Waste Isolation in Geologic Formations,'' Y/OWI/TM-44. The series provides a more complete technical basis for the preconceptual designs, resource requirements, and environmental source terms associated with isolating commercial LWR wastes in underground repositories in salt, granit