repository system phase: Topics by WorldWideScience.org

Sample records for repository system phase

National Geoscience Data Repository System: Phase 2 final report

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-07-01

The American Geological Institute (AGI) has completed Phase 2 of a project to establish a National Geoscience Data Repository System (NGDRS). The project`s primary objectives are to preserve geoscience data in jeopardy of being destroyed and to make that data available to those who have a need to use it in future investigations. These data are available for donation to the public as a result of the downsizing that has occurred in the major petroleum and mining companies in the US for the past decade. In recent years, these companies have consolidated domestic operations, sold many of their domestic properties and relinquished many of their leases. The scientific data associated with those properties are no longer considered to be useful assets and are consequently in danger of being lost forever. The national repository project will make many of these data available to the geoscience community for the first time. Phase 2 encompasses the establishment of standards for indexing and cataloging of geoscience data and determination of the costs of transferring data from the private sector to public-sector data repositories. Pilot projects evaluated the feasibility of the project for transfer of different data types and creation of a Web-based metadata supercatalog and browser. Also as part of the project, a national directory of geoscience data repositories was compiled to assess what data are currently available in existing facilities. The next step, Phase 3, will focus on the initiation of transfer of geoscience data from the private sector to the public domain and development of the web-based Geotrek metadata supercatalog.
Overview of adaptive phased management repository design development

International Nuclear Information System (INIS)

Russell, S.

2011-01-01

The Nuclear Waste Management Organization is implementing Adaptive Phased Management, Canada's plan for long-term management of used nuclear fuel. The organization is proceeding with the process for selecting a site in partnership with an informed and willing host community to safely and securely container and isolate used nuclear fuel in a deep geological repository in a suitable rock formation. Adaptive Phased Management is the culmination of more than 30 years of research, development and demonstration of repository concepts in Canada. Adaptive Phased Management uses a phased and adaptive step-wise approach to the multi-barrier system which is consistent with the long-term waste management approaches being developed in many other countries with nuclear power programs such as Sweden, Finland, Switzerland, the United Kingdom and France. The Nuclear Waste Management Organization is examining and developing conceptual designs for a deep geological repository and associated facilities for the placement of used nuclear fuel in long-lived containers. This paper will examine two of these generic conceptual designs which have recently been refined and updated. These conceptual designs will be used to support a pre-project review of repository design and safety by the Canadian Nuclear Safety Commission. (author)
Synthesis of tobermorite: A cement phase expected under repository conditions

International Nuclear Information System (INIS)

Martin, S.I.

1994-11-01

In this study I have synthesized tobermorite, Ca 5 Si 6 O l6 (OH) 2. 4H 2 0, a principal crystalline phase expected to form in cementitious materials subjected to elevated temperatures in a potential nuclear waste repository. Fluids interacting with these materials may have a profound effect on the integrity of the waste package and on transport of radionuclides. At ambient temperature, Portland cement reacts with water to form an amorphous calcium-silicate-hydrate (C-S-H) gel. At elevated temperatures, crystalline phases of various hydration states form. The C-S-H system has not been well characterized at elevated temperatures up to 250 degrees C, which has been considered a bounding temperature for the potential Yucca Mountain repository. Physical, chemical, and thermodynamic data for these cement minerals that are predicted to be stable at these temperatures must be obtained from synthetic or natural samples to help predict fluid chemistry. For some of these minerals natural samples are difficult to obtain in sufficient quantity and purity. Therefore, monomineralic phases must be synthesized in order to unambiguously define their behavior. The synthetic or natural phases will be characterized as part of a comprehensive study to define the behavior of cementitious materials in a repository environment
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
Phase 1 study of metallic cask systems for spent fuel management from reactor to repository. Volume I. Phase 1 study summary

International Nuclear Information System (INIS)

1986-02-01

It was proposed to perform a systems evaluation of metallic cask systems in order to define and examine the use of various metallic cask concepts or combination of concepts for the overall inventory management of spent fuel starting with its discharge from reactors to its emplacement in geologic repositories. This systems evaluation occurs in three phases. This three phase systems evaluation leads to a definition and recommendation of a sound and practical metallic cask system to accomplish efficient and effective management of spent fuel in the back end of the nuclear fuel cycle. Phase 1 Study objectives: establish system-wide functional criteria and assumptions; perform the systems engineering needed to define the metallic cask concepts and their feasibility; perform a screening evaluation of the technical and economic merits of the concepts; and recommend those to be included for a more detailed systems evaluation in Phase 2. Phase 2 Study objectives: refine the system-wide functional criteria and assumptions; perform the design engineering needed to enhance the validity and workability of those concepts recommended in Phase 1; and perform a more detailed systems evaluation. Phase 3 Study objectives: conclude the systems evaluation and develop an implementation plan. Volume I presents an overview of the detailed systems evaluation presented in Volume II
National Geoscience Data Repository System, Phase II. Final report, January 30, 1995--January 28, 1997

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-04-01

The American Geological Institute (AGI) has completed Phase II of a project to establish a National Geoscience Data Repository System (NGDRS). The project`s primary objectives are to preserve geoscience data in jeopardy of being destroyed and to make that data available to those who have a need to use it in future investigations. These data are available for donation to the public as a result of the downsizing that has occurred in the major petroleum and mining companies in the United States for the past decade. In recent years, these companies have consolidated domestic operations, sold many of their domestic properties and relinquished many of their leases. The scientific data associated with those properties are no longer considered to be useful assets and are consequently in danger of being lost forever. The national repository project will make many of these data available to the geoscience community for the first time. To address this opportunity, AGI sought support from the Department of Energy (DOE) in 1994 to initiate the NGDRS Phase I feasibility study to determine the types and quantity of data that companies would be willing to donate. The petroleum and mining companies surveyed indicated that they were willing to donate approximately five million well logs, one hundred million miles of seismic reflection data, millions of linear feet of core and cuttings, and a variety of other types of scientific data. Based on the positive results of the Phase I study, AGI undertook Phase II of the program in 1995. Funded jointly by DOE and industry, Phase II encompasses the establishment of standards for indexing and cataloging of geoscience data and determination of the costs of transferring data from the private sector to public-sector data repositories. Pilot projects evaluated the feasibility of the project for transfer of different data types and creation of a Web-based metadata supercatalog and browser.
Development and application of a quality assurance system for waste repositories

International Nuclear Information System (INIS)

Beckmerhagen, I.; Berg, H.P.

1996-01-01

A large set of requirements are developed for the structures, systems and components of a waste repository. These requirements cover different regulations concerning planning, design, construction, operation and decommissioning of a waste repository as well as nuclear-specific requirements on the design of the plant. The implementation of a quality assurance (QA) system is an essential task in order to ensure that the requirements are fulfilled by systematic means. The QA system for the German repositories for radioactive waste is built up as a hierarchic system and described in more detail in particular covering aspects like maintenance of QA relevant systems, structures and components as well as the procedure in case of changes. For the operational phase of a repository a separate site-specific manual had to be developed. Such a manual has been elaborated for the operation of the Morsleben repository; main topics of this manual are presented
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
National radioactive waste repository site selection study. Phase 2. A report on public comment

International Nuclear Information System (INIS)

1995-11-01

Agreement was reached in principle between State/Territory and the Commonwealth of Australia Governments that a suitable site for a radioactive wastes repository must be found. The discussion papers resulting from the Phase 1 and Phase 2 of the site selection study were released for public comment. The national repository will be for disposal of low level and short-lived intermediate level radioactive wastes streaming from the medical, research and industrial use of radioisotopes in Australia. The purpose of this report is to summarise and respond in general terms to comment received on the discussion paper -Phase 2 of the study. Forty five submissions were received. Of these: 18 supported the Phase 2 study approach and the concept of a national repository; 13 did not state a clear position but either requested more information or provided constructive comment on the siting process; 7 supported the site selection approach and the repository concept but suggested that the repository should not be sited in a particular area; 3 opposed the siting of the repository in their vicinity but not necessarily the repository concept and site selection approach; 4 opposed the concept of a national repository. This compares with 124 submissions on Phase 1 of the study, of which 57 opposed the national repository concept (52 of these were from letters elicited by Greenpeace) and 48 supported the establishment of a national repository and the site selection approach proposed. 3 figs
Corrosion phase formation on container alloys in basalt repository environments

International Nuclear Information System (INIS)

Johnston, R.G.; Anantatmula, R.P.; Lutton, J.M.; Rivera, C.L.

1986-01-01

The Basalt Waste Isolation Project is evaluating the suitability of basalt in southeastern Washington State as a possible location for a nuclear waste repository. The performance of the waste package, which includes the waste form, container, and surrounding packing material, will be affected by the stability of container alloys in the repository environment. Primary corrosion phases and altered packing material containing metals leached from the container may also influence subsequent reactions between the waste form and repository environment. Copper- and iron-based alloys were tested at 50 0 to 300 0 C in an air/steam environment and in pressure vessels in ground-water-saturated basalt-bentonite packing material. Reaction phases formed on the alloys were identified and corrosion rates were measured. Changes in adhering packing material were also evaluated. The observed reactions and their possible effects on container alloy durability in the repository are discussed
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
Long-Term Information Management (LTIM) of Safeguards Data at Repositories: Phase II

International Nuclear Information System (INIS)

Haddal, Risa N.

2016-01-01

One of the challenges of implementing safeguards for geological repositories will be the long-term preservation of safeguards-related data for 100 years or more. While most countries considering the construction and operation of such facilities agree that safeguards information should be preserved, there are gaps with respect to standardized requirements, guidelines, timescales, and approaches. This study analyzes those gaps and explores research to clarify stakeholder needs, identify current policies, approaches, best practices and international standards, and explores existing safeguards information management infrastructure. The study also attempts to clarify what a safeguards data classification system might look like, how long data should be retained, and how information should be exchanged between stakeholders at different phases of a repository's life cycle. The analysis produced a variety of recommendations on what information to preserve, how to preserve it, where to store it, retention options and how to exchange information in the long term. Key findings include the use of the globally recognized international records management standard, ISO15489, for guidance on the development of information management systems, and the development of a Key Information File (KIF). The KIF could be used to identify only the most relevant, high-level safeguards information and the history of decision making about the repository. The study also suggests implementing on-site and off-site records storage in digital and physical form; developing a safeguards data classification system; long-term records retention with periodic reviews every 5 to 10 years during each phase of the repository life cycle; and establishing transition procedures well in advance so that data shepherds and records officers can transfer information with incoming facility managers effectively and efficiently. These and other recommendations are further analyzed in this study.
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
Development of the Canadian used fuel repository engineered barrier system

Energy Technology Data Exchange (ETDEWEB)

Hatton, C., E-mail: chatton@nwmo.ca [Nuclear Waste Management Organization, Toronto, ON (Canada)

2015-07-01

The Nuclear Waste Management Organization (NWMO) is responsible for the implementation of Adaptive Phased Management (APM), the federally-approved plan for the safe long-term management of Canada's used nuclear fuel. Under the APM plan, used nuclear fuel will ultimately be placed within a deep geological repository in a suitable rock formation. In implementing APM, the NWMO is committed to ensure consistency with international best practices in the development of its repository system, including any advances in technology. In 2012, the NWMO undertook an optimization study to look at both the design and manufacture of its engineered barriers. This study looked at current technologies for the design and manufacture of used fuel containers, placement technologies, repository design, and buffer and sealing systems, while taking into consideration the state of the art worldwide in repository design and acceptance. The result of that study is the current Canadian engineered barrier system, consisting of a 2.7 tonne used fuel container with a carbon-steel core, copper-coated surface and welded spherical heads. The used fuel container is encapsulated in a bentonite buffer box at the surface and then transferred underground. Once underground, the used fuel is placed into a repository room which is cut into the rock using traditional drill-and-blast technologies. This paper explains the logic for the selection of the container and sealing system design and the development of innovative technologies for their manufacture including the use of laser welding, cold spray and pulsed-electrodeposition copper coating for the manufacture of the used fuel container, isostatic presses for the production of the one-piece bentonite blocks, and slip-skid technologies for placement into the repository. (author)
Development of the Canadian used fuel repository engineered barrier system

International Nuclear Information System (INIS)

Hatton, C.

2015-01-01

The Nuclear Waste Management Organization (NWMO) is responsible for the implementation of Adaptive Phased Management (APM), the federally-approved plan for the safe long-term management of Canada's used nuclear fuel. Under the APM plan, used nuclear fuel will ultimately be placed within a deep geological repository in a suitable rock formation. In implementing APM, the NWMO is committed to ensure consistency with international best practices in the development of its repository system, including any advances in technology. In 2012, the NWMO undertook an optimization study to look at both the design and manufacture of its engineered barriers. This study looked at current technologies for the design and manufacture of used fuel containers, placement technologies, repository design, and buffer and sealing systems, while taking into consideration the state of the art worldwide in repository design and acceptance. The result of that study is the current Canadian engineered barrier system, consisting of a 2.7 tonne used fuel container with a carbon-steel core, copper-coated surface and welded spherical heads. The used fuel container is encapsulated in a bentonite buffer box at the surface and then transferred underground. Once underground, the used fuel is placed into a repository room which is cut into the rock using traditional drill-and-blast technologies. This paper explains the logic for the selection of the container and sealing system design and the development of innovative technologies for their manufacture including the use of laser welding, cold spray and pulsed-electrodeposition copper coating for the manufacture of the used fuel container, isostatic presses for the production of the one-piece bentonite blocks, and slip-skid technologies for placement into the repository. (author)
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)
Long-Term Information Management (LTIM) of Safeguards Data at Repositories: Phase II

Energy Technology Data Exchange (ETDEWEB)

Haddal, Risa N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2016-10-01

One of the challenges of implementing safeguards for geological repositories will be the long-term preservation of safeguards-related data for 100 years or more. While most countries considering the construction and operation of such facilities agree that safeguards information should be preserved, there are gaps with respect to standardized requirements, guidelines, timescales, and approaches. This study analyzes those gaps and explores research to clarify stakeholder needs, identify current policies, approaches, best practices and international standards, and explores existing safeguards information management infrastructure. The study also attempts to clarify what a safeguards data classification system might look like, how long data should be retained, and how information should be exchanged between stakeholders at different phases of a repository’s life cycle. The analysis produced a variety of recommendations on what information to preserve, how to preserve it, where to store it, retention options and how to exchange information in the long term. Key findings include the use of the globally recognized international records management standard, ISO15489, for guidance on the development of information management systems, and the development of a Key Information File (KIF). The KIF could be used to identify only the most relevant, high-level safeguards information and the history of decision making about the repository. The study also suggests implementing on-site and off-site records storage in digital and physical form; developing a safeguards data classification system; long-term records retention with periodic reviews every 5 to 10 years during each phase of the repository life cycle; and establishing transition procedures well in advance so that data shepherds and records officers can transfer information with incoming facility managers effectively and efficiently. These and other recommendations are further analyzed in this study.
Fluid flow and radionuclide transport in complex repository mines. Synthesis report part 1/2. Two-phase flow in a saline repository using the example ERAM; Fluidstroemung und Radionuklidtransport in komplexen Endlagerbergwerken. Synthesebericht Teil 1/2. Zweiphasenfluss in einem salinaren Endlager am Beispiel des ERAM

Energy Technology Data Exchange (ETDEWEB)

Kock, Ingo; Frieling, Gerd; Navarro, Martin

2016-10-15

The aim of the project is the understanding of two-phase flow processes in a complex final repository system. The consideration of two-phase flow processes for calculations concerning the modeled final repository system induces processes and effects that influence the fluid and radionuclide transport significantly. Two-phase flow processes cover not only capillary pressures and the relative permeability but also a basic competition of phases for the pore volume with respect to storage and transport and density driven vertical phase separation.
Assessing the potentialities of integrated modelling during early phases of siting and design of a geological repository: the REGIME exercise

Energy Technology Data Exchange (ETDEWEB)

Genty, A.; Certes, C.; Serres, C.; Besnus, F. [Institut de Radioprotection et de Surete Nucleaire IRSN, 92 - Fontenay aux Roses (France); Fischer-Appelt, K.; Baltes, B.; Rohlig, J. [Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH (GRS), Koeln (Germany)

2003-01-01

This paper presents the safety assessment exercise 'REGIME' (Repository Evaluation performed by GRS and IRSN through a Modelling Exercise) performed jointly by GRS and IRSN. The main objective of the project is to test the ability of integrated modelling to contribute to site selection and repository conception in the context of high-level radioactive waste disposal. The project is divided in two parts. Phase 1 consisted in studying different flow patterns in a given geological context. The selected hydrogeological contexts and three site locations potentially favourable for hosting a repository are described. Phase 2, under progress, aims at evaluating the rote of limitation of releases played by the different components of the disposal system taking into account possible dysfunctions. The main issues to be addressed in phase 2, the modelling outline and the scenarios to be studied are presented. (authors)
Local-scale modelling of density-driven flow for the phases of repository operation and post-closure at Beberg

International Nuclear Information System (INIS)

Jaquet, O.; Siegel, P.

2004-09-01

A hydrogeological model was developed for Beberg with the aim of evaluating the impact of a repository (for the operational and post-closure phases) while accounting for the effects of density-driven flow. Two embedded scales were taken into account for this modelling study: a local scale at which the granitic medium was considered as a continuum and a repository scale, where the medium is fractured and therefore was regarded to be discrete. The following step-wise approach was established to model density-driven flow at both repository and local scale: (a) modelling fracture networks at the repository scale, (b) upscaling the hydraulic properties to a continuum at local scale and (c) modelling density-driven flow to evaluate repository impact at local scale. The results demonstrate the strong impact of the repository on the flow field during the phase of operation. The distribution of the salt concentration is affected by a large upcoming effect with increased relative concentration and by the presence of fracture zones carrying freshwater from the surface. The concentrations obtained for the reference case, expressed in terms of percentage with respect to the maximum (prescribed) value in the model, are as follows: ca 30% for the phase of desaturation, and ca 20% for the resaturation phase. For the reference case, the impact of repository operations appears no longer visible after a resaturation period of about 20 years after repository closure; under resaturation conditions, evidence of the operational phase has already disappeared in terms of the observed hydraulic and concentration fields. Sensitivity calculations have proven the importance of explicitly discretising repository tunnels when assessing resaturation time and maximum concentration values. Furthermore, the definition of a fixed potential as boundary condition along the model's top surface is likely to provide underestimated values for the maximum concentration and overestimated flow rates in the

SUBSURFACE REPOSITORY INTEGRATED CONTROL SYSTEM DESIGN

International Nuclear Information System (INIS)

C.J. Fernado

1998-01-01

The purpose of this document is to develop preliminary high-level functional and physical control system architectures for the proposed subsurface repository at Yucca Mountain. This document outlines overall control system concepts that encompass and integrate the many diverse systems being considered for use within the subsurface repository. This document presents integrated design concepts for monitoring and controlling the diverse set of subsurface operations. The subsurface repository design will be composed of a series of diverse systems that will be integrated to accomplish a set of overall functions and objectives. The subsurface repository contains several Instrumentation and Control (I andC) related systems including: waste emplacement systems, ventilation systems, communication systems, radiation monitoring systems, rail transportation systems, ground control monitoring systems, utility monitoring systems (electrical, lighting, water, compressed air, etc.), fire detection and protection systems, retrieval systems, and performance confirmation systems. Each of these systems involve some level of I andC and will typically be integrated over a data communication network. The subsurface I andC systems will also integrate with multiple surface-based site-wide systems such as emergency response, health physics, security and safeguards, communications, utilities and others. The scope and primary objectives of this analysis are to: (1) Identify preliminary system level functions and interface needs (Presented in the functional diagrams in Section 7.2). (2) Examine the overall system complexity and determine how and on what levels these control systems will be controlled and integrated (Presented in Section 7.2). (3) Develop a preliminary subsurface facility-wide design for an overall control system architecture, and depict this design by a series of control system functional block diagrams (Presented in Section 7.2). (4) Develop a series of physical architectures
SUBSURFACE REPOSITORY INTEGRATED CONTROL SYSTEM DESIGN

Energy Technology Data Exchange (ETDEWEB)

C.J. Fernado

1998-09-17

The purpose of this document is to develop preliminary high-level functional and physical control system architectures for the proposed subsurface repository at Yucca Mountain. This document outlines overall control system concepts that encompass and integrate the many diverse systems being considered for use within the subsurface repository. This document presents integrated design concepts for monitoring and controlling the diverse set of subsurface operations. The subsurface repository design will be composed of a series of diverse systems that will be integrated to accomplish a set of overall functions and objectives. The subsurface repository contains several Instrumentation and Control (I&C) related systems including: waste emplacement systems, ventilation systems, communication systems, radiation monitoring systems, rail transportation systems, ground control monitoring systems, utility monitoring systems (electrical, lighting, water, compressed air, etc.), fire detection and protection systems, retrieval systems, and performance confirmation systems. Each of these systems involve some level of I&C and will typically be integrated over a data communication network. The subsurface I&C systems will also integrate with multiple surface-based site-wide systems such as emergency response, health physics, security and safeguards, communications, utilities and others. The scope and primary objectives of this analysis are to: (1) Identify preliminary system level functions and interface needs (Presented in the functional diagrams in Section 7.2). (2) Examine the overall system complexity and determine how and on what levels these control systems will be controlled and integrated (Presented in Section 7.2). (3) Develop a preliminary subsurface facility-wide design for an overall control system architecture, and depict this design by a series of control system functional block diagrams (Presented in Section 7.2). (4) Develop a series of physical architectures that
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.
Representation of two-phase flow in the vicinity of the repository in the 1996 performance assessment for the Waste Isolation Pilot Plant

International Nuclear Information System (INIS)

VAUGHN, PALMER; BEAN, J.E.; HELTON, JON CRAIG; LORD, MICHAEL E.; MACKINNON, ROBERT J.; SCHREIBER, JAMES D.

2000-01-01

The following topics related to the representation of two-phase (gas and brine) flow in the vicinity of the repository in the 1996 performance assessment (PA) for the Waste Isolation Pilot Plant (WIPP) are discussed: (1) system of nonlinear partial differential equations used to model two-phase flow, (2) incorporation of repository shafts into model (3) creep closure of repository. (4) interbed fracturing, (5) gas generation (6) capillary action in waste, (7) borebole model (8) numerical solution and (9) gas and brine flow across specified boundaries. Two-phase flow calculations are a central part of the 1996 WIPP PA and supply results that are subsequently used in the calculation of releases to the surface at the time of a drilling intrusion (i.e., spallings, direct brine releases) and long-term releases due to radionuclide transport by flowing groundwater
Construction of First Phase of Spent Fuel Repository in Finland: Lessons Learned and Success Factors

International Nuclear Information System (INIS)

Varjoranta, T.; Paltemaa, R.

2015-01-01

The Finnish nuclear legislation defines spent fuel as nuclear waste and requires that it has to be disposed of in the Finnish bedrock. Over 30 years of systematic R&D has been carried out to develop the repository concept, site selection, technologies, safety assessment and the regulatory approach. Activities are based on the Finnish Government’s long term strategies since 1983 and the public acceptance at local, Governmental and Parliament levels, approved and documented in the legal “Decision in Principle” (DiP) in 2000 to locate the repository at Olkiluoto. The DiP provided authorization to construct the first phase of the repository to the depth of the planned disposal. The construction of the 1 st phase of the repository started 2004 and has now reached the depth of 407 m. This paper identifies and discusses lessons learned and key success factors of the progress made. (author)
Multi-physical process and system analysis for geological underground repositories in clay formations in the post closure phase; Multiphysikalische Prozess- und Systemanalyse fuer geologische Tiefenlager im Tonsteingebirge in der Nachverschlussphase

Energy Technology Data Exchange (ETDEWEB)

Zhao, Juan

2017-09-21

In the framework of a safety case for repository systems in deep geological formations used for the disposal of high-level radioactive heat-generating waste, the THM-coupled long-term behaviour of such systems has to be analysed with consideration of 2-phase flow processes. These analyses are carried out for the repository near field and the isolating rock mass zone by performing numerical simulations, which require a sufficient process and system understanding with regard to the coupled physical processes involved and their interaction in the respective rock mass formation. The topic of this Ph.D. work is the analysis of the long-term system behaviour of a reference repository system built in clay stone rock mass. Therefore, numerical simulations have been carried out using the FTK-simulation tool which has been developed at the Chair in Waste Disposal and Geomechanics at the Clausthal University of Technology, in order to improve the process and system understanding for repository systems in the clay stone rock mass. In this context, the FTK-simulation tool is at first validated further by performing retrospective analyses of selected field and laboratory tests documented in the national and international literature, as well as of numerical simulation examples regarding the thermohydromechanical load-bearing behaviour of emplacement drifts. Besides, the FTK-simulation tool is used to perform a prognostic analysis concerning the laboratory investigations, which have been planned to qualitatively as well as quantitatively characterise the 2-phase flow properties of clay stone. In addition, a functional model approach is presented, which allows an abstract modeling of the secondary permeability development in the near field of drifts or shafts excavated and backfilled in clay stone rock mass as a function of the swelling pressure development in the bentonite backfill material. Finally, a comprehensive variation analysis is presented, which has been carried out for a
Two-phase flow in a saliniferous final repository using the example of ERAM. Final report; Zweiphasenfluss in einem salinaren Endlager am Beispiel des ERAM. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Kock, Ingo; Frieling, Gerd; Navarro, Martin

2016-10-15

In the frame of the research project ZIESEL the GRS enhanced the state of science and technology for the realization and evaluation of long-term safety cases for the final deposition of radioactive wastes. The superior aim was the improved understanding of two-phase flow processes in a complex final repository system. The consideration of two-phase processes in modeling of final repository systems induces processes and effects that significantly affect the transport behavior of fluid and radionuclides. Two-phase processes include not only capillary pressures and relative permeabilities but also a basic competition of phases with respect to pore volume for storage and transport and density-driven vertical separation of phases. Basically seals have been shown to be essential for the system behavior because of their influence of the gas pressure dependent control function. The system behavior is also influences by the model geometry.
System description of the Repository-Only System for the FY 1990 systems integration program studies

International Nuclear Information System (INIS)

McKee, R.W.; Young, J.R.; Konzek, G.J.

1991-07-01

This document provides both functional and physical descriptions of a conceptual high-level waste management system defined as a Repository-Only System. Its purpose is to provide a basis for required system computer modeling and system studies initiated in FY 1990 under the Systems Integration Program of the US Department of Energy's (DOE) Office of Civilian Radioactive Waste Management (OCRWM). The Repository-Only System is designed to accept 3000 MTU per year of spent fuel and 400 equivalent MTU per year of high-level wastes disposal in the geologic repository. This document contains both functional descriptions of the processes in the waste management system and physical descriptions of the equipment and facilities necessary for performance of those processes. These descriptions contain the level of detail needed for the projected systems analysis studies. The Repository-Only System contains all system components, from the waste storage facilities of the waste generators to the underground facilities for final disposal of the wastes. The major facilities in the system are the waste generator waste storage facilities, a repository facility that packages the wastes and than emplaces them in the geologic repository, and the transportation equipment and facilities for transporting the wastes between these major facilities. 18 refs., 39 figs
Reference design description for a geologic repository. Revision 02

International Nuclear Information System (INIS)

1999-01-01

This Reference Design Description explains the current design for a potential geologic repository that may be located at Yucca Mountain in Nevada. It describes the proposed design for a surface facility, subsurface repository, and waste packaging; it also presents the current design of the key engineering systems for the final four phases: operations, monitoring, closure, and postclosure. In addition, this Reference Design Description reviews the expected long-term performance of the potential repository. In accordance with current law, this design does not include an interim storage option. This document has six major sections. Section 1 describes the physical layout of the proposed repository. The second section describes the 4-phase evolution of the development of the proposed repository. Section 3 describes the reception of waste from offsite locations. The fourth section details the various systems that will package the waste and move it below ground as well as safety monitoring and closure. Section 5 describes the systems (both physical and analytical) that ensure continued safety after closure. The final section offers design options that may be adopted to increase the margin of safety
Technical realization of a closure concept for a chamber-system in the underground Richard repository in the Czech Republic

International Nuclear Information System (INIS)

Kucerka, Miroslav

2006-01-01

The Phare project CZ 632.02.04 'Realization of closure of a chamber in the Richard repository as input for establishing a safety case' is a follow up implementation phase of the Phare project, CZ 01.14.03 'Solution for closure of a chamber in the Richard repository'. Main objective of both projects is to propose and realize a disposal system in selected chambers of the Richard repository, which will eliminate burden from the past practices in waste management during the first phase of the Richard repository operation (1965 - 1980) and which will improve its overall long term safety. This objective will be assured by realization of the concept of so called 'hydraulic cage', which technical solution was developed by DBE Technology within the Phare project CZ 01.14.03. The solution is described in the previous presentation 'Hydraulic Cage Concept for Waste Chambers and its Technical Implementation for the Underground Richard Repository, Litomerice, Czech Republic'. (author)
Multibarrier system preventing migration of radionuclides from radioactive waste repository

Directory of Open Access Journals (Sweden)

Olszewska Wioleta

2015-09-01

Full Text Available Safety of radioactive waste repositories operation is associated with a multibarrier system designed and constructed to isolate and contain the waste from the biosphere. Each of radioactive waste repositories is equipped with system of barriers, which reduces the possibility of release of radionuclides from the storage site. Safety systems may differ from each other depending on the type of repository. They consist of the natural geological barrier provided by host rocks of the repository and its surroundings, and an engineered barrier system (EBS. The EBS may itself comprise a variety of sub-systems or components, such as waste forms, canisters, buffers, backfills, seals and plugs. The EBS plays a major role in providing the required disposal system performance. It is assumed that the metal canisters and system of barriers adequately isolate waste from the biosphere. The evaluation of the multibarrier system is carried out after detailed tests to determine its parameters, and after analysis including mathematical modeling of migration of contaminants. To provide an assurance of safety of radioactive waste repository multibarrier system, detailed long term safety assessments are developed. Usually they comprise modeling of EBS stability, corrosion rate and radionuclide migration in near field in geosphere and biosphere. The principal goal of radionuclide migration modeling is assessment of the radionuclides release paths and rate from the repository, radionuclides concentration in geosphere in time and human exposure to ionizing radiation
Salt Repository Project transportation system interface requirements: Transportation system/repository receiving facility interface requirements

International Nuclear Information System (INIS)

Smith, L.A.; Insalaco, J.W.; Trainer, T.A.

1988-01-01

This report is a preliminary review of the interface between the transportation system and the repository receiving facility for a nuclear waste mined geologic disposal system in salt. Criteria for generic cask and facility designs are developed. These criteria are derived by examining the interfaces that occur as a result of the operations needed to receive nuclear waste at a repository. These criteria provide the basis for design of a safe, operable, practical nuclear waste receiving facility. The processing functions required to move the shipping unit from the gate into the unloading area and back to the gate for dispatch are described. Criteria for a generic receiving facility are discussed but no specific facility design is presented or evaluated. The criteria are stated in general terms to allow application to a wide variety of cask and facility designs. 9 refs., 6 figs., 4 tabs
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.
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
National Geoscience Data Repository System: Phase 2 -- Planning and pilot study. Progress report, 1. quarter, January--March 1997

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-04-01

The NGDRS goal is to preserve and make geoscience and engineering data readily accessible to those who have an interest in using such data. To achieve this goal requires the careful management of the process for transferring data from data providers to the public domain and the creation of the information systems organization and infrastructure to allow data consumers to find and access the data. This report describes the NGDRS organization structure; the development of a directory of existing geoscience data repositories; the financial models for data transfer (seismic data transfer, core data transfer, and data browser); and the overall architecture of the repository system.
VerSi. A method for the quantitative comparison of repository systems

Energy Technology Data Exchange (ETDEWEB)

Kaempfer, T.U.; Ruebel, A.; Resele, G. [AF-Consult Switzerland Ltd, Baden (Switzerland); Moenig, J. [GRS Braunschweig (Germany)

2015-07-01

Decision making and design processes for radioactive waste repositories are guided by safety goals that need to be achieved. In this context, the comparison of different disposal concepts can provide relevant support to better understand the performance of the repository systems. Such a task requires a method for a traceable comparison that is as objective as possible. We present a versatile method that allows for the comparison of different disposal concepts in potentially different host rocks. The condition for the method to work is that the repository systems are defined to a comparable level including designed repository structures, disposal concepts, and engineered and geological barriers which are all based on site-specific safety requirements. The method is primarily based on quantitative analyses and probabilistic model calculations regarding the long-term safety of the repository systems under consideration. The crucial evaluation criteria for the comparison are statistical key figures of indicators that characterize the radiotoxicity flux out of the so called containment-providing rock zone (einschlusswirksamer Gebirgsbereich). The key figures account for existing uncertainties with respect to the actual site properties, the safety relevant processes, and the potential future impact of external processes on the repository system, i.e., they include scenario-, process-, and parameter-uncertainties. The method (1) leads to an evaluation of the retention and containment capacity of the repository systems and its robustness with respect to existing uncertainties as well as to potential external influences; (2) specifies the procedures for the system analyses and the calculation of the statistical key figures as well as for the comparative interpretation of the key figures; and (3) also gives recommendations and sets benchmarks for the comparative assessment of the repository systems under consideration based on the key figures and additional qualitative
Project JADE. Long-term function and safety. Comparison of repository systems

International Nuclear Information System (INIS)

Birgersson, Lars; Pers, K.; Wiborgh, M.

2001-12-01

A comparison of the KBS-3 V(ertical deposition), KBS-3 H(orizontal deposition) and MLH repository systems with regard to the long-term repository performance and the radionuclide migration is presented in the report. Several differences between the repository systems have been identified. The differences are mainly related to the: distance between canister and backfilled tunnels, excavated rock volumes, deposition hole direction. The overall conclusion is that the differences are in general quite small with regard to the repository function and safety. None of the differences are of such importance for the long-term repository performance and radionuclide migration that they discriminate any of the repository systems. The differences between the two KBS-3 systems are small. Based on this study, there is no reason to change from the reference system KBS-3 V to KBS-3 H. MLH has the potential to be a very robust system, especially in a long-term perspective. However, the MLH system will require extensive research, development, and analysis before it will be as confident as the reference repository system, KBS-3 V. Although the MLH and KBS-3 H systems are in some ways favourable compared to the reference system KBS-3 V, the overall conclusion is that the KBS-3 V system is still a very attractive system. A major advantage with KBS-3 V is that it is by far the most investigated and developed system. The JADE-project was initiated in 1996, and the main part of the study was carried out during 1997 and 1998. The JADE study is consequently based on presumptions that were valid a few years ago. Some of these presumptions have been modified since then. The new presumptions are however not judged to change the overall conclusions
Planning the rad waste repository - Croatian case

International Nuclear Information System (INIS)

Kucar Dragicevic, S.; Subasic, D.; Lokner, V.

1996-01-01

Radioactive waste is generated in Croatia from various nuclear applications as well as from the Krsko NPP (Slovenian and Croatian joint venture facility). The national programme on radioactive waste management is aimed at straightening existing infrastructure, establishing new (more transparent) system of responsibilities and development of new legislation. The siting of LL/ILW repository is important segments of the whole radioactive waste management cycle. The status and efficiency of the rad waste management infrastructure in the country have the significant influence on all the activities related to the project of repository construction - from the very first phases of preliminary planning and background preparations to advanced phases of the project development. The present status of the Croatian national radioactive waste infrastructure and its influence on the repository project are presented. The role of national legislation and institutional framework are specially discussed. (author)
Space Telecommunications Radio System (STRS) Application Repository Design and Analysis

Science.gov (United States)

Handler, Louis M.

2013-01-01

The Space Telecommunications Radio System (STRS) Application Repository Design and Analysis document describes the STRS application repository for software-defined radio (SDR) applications intended to be compliant to the STRS Architecture Standard. The document provides information about the submission of artifacts to the STRS application repository, to provide information to the potential users of that information, and for the systems engineer to understand the requirements, concepts, and approach to the STRS application repository. The STRS application repository is intended to capture knowledge, documents, and other artifacts for each waveform application or other application outside of its project so that when the project ends, the knowledge is retained. The document describes the transmission of technology from mission to mission capturing lessons learned that are used for continuous improvement across projects and supporting NASA Procedural Requirements (NPRs) for performing software engineering projects and NASAs release process.
Prototype Repository. Tracer dilution tests during operation phase, test campaign 3

Energy Technology Data Exchange (ETDEWEB)

Harrstroem, Johan; Andersson, Peter (Geosigma AB (Sweden))

2010-05-15

The Prototype Repository project is focused on testing and demonstrating the function of the SKB deep repository system. The third tracer dilution campaign during the Prototype Repository operation period was performed in January 2010. The purpose was to estimate the groundwater flows and hydraulic gradients in the boreholes vicinity and will function as a reference for comparison with results from modeling and prior assumptions. The test campaign consisted of tracer dilution tests in 13 different borehole sections. Each test consisted of approximately 15-55 min tracer injection time and about 1-3 days dilution test time depending on the transmissivity of the test section. The data interpretation also included estimates of the local hydraulic gradients in the vicinity of the borehole sections

Potential site selection for radioactive waste repository using GIS (Study area: Negeri Sembilan) - Phase 1

International Nuclear Information System (INIS)

Ahmad Hasnulhadi Che Kamaruddin; Faizal Azrin Abdul Razalim; Mohd Abdul Wahab Yusof; Nik Marzukee Nik Ibrahim; Nazran Harun; Muhammad Fathi Sujan; Karuppiah, T.; Surip, N.; Malik, N.N.A.; Che Musa, R.

2010-01-01

The main purpose in this paper is to create the Geographic Information System (GIS) based analysis on the potential site area for near-surface radioactive waste repository in the state of Negeri Sembilan. There are several parameters should be considered related to the safety assessment in selecting the potential site. These parameters such as land-use, urban area, soil, rainfall, lithology, lineament, geomorphology, landslide potential, slope, elevation, hydrogeology and protected land need to be considered before choosing the site. In this phase, we only consider ten parameters for determining the potential suitable site. (author)
Monitored retrievable storage (MRS) facility and salt repository integration: Engineering study report

International Nuclear Information System (INIS)

1987-07-01

This MRS Facility and Salt Repository Integration Study evaluates the impacts of an integrated MRS/Salt Repository Waste Management System on the Salt Repository Surface facilities' design, operations, cost, and schedule. Eight separate cases were studied ranging from a two phase repository design with no MRS facility to a design in which the repository only received package waste from the MRS facility for emplacement. The addition of the MRS facility to the Waste Management System significantly reduced the capital cost of the salt repository. All but one of the cases studied were capable of meeting the waste acceptance data. The reduction in the size and complexity of the Salt Repository waste handling building with the integration of the MRS facility reduces the design and operating staff requirements. 7 refs., 35 figs., 43 tabs
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
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
The Age-ility Project (Phase 1): Structural and functional imaging and electrophysiological data repository

NARCIS (Netherlands)

Karayanidis, F.; Keuken, M.C.; Wong, A.; Rennie, J.L.; de Hollander, G.; Cooper, P.S.; Fulham, W.R.; Lenroot, R.; Parsons, M.; Philips, N.; Michie, P.T.; Forstmann, B.U.

2015-01-01

Our understanding of the complex interplay between structural and functional organisation of brain networks is being advanced by the development of novel multi-modal analyses approaches. The Age-ility Project (Phase 1) data repository offers open access to structural MRI, diffusion MRI, and
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
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
Monitoring system specifications: retrieval of surf from a salt repository

International Nuclear Information System (INIS)

1980-01-01

The task of developing specifications for a reference monitoring system determined by repository environmental conditions, retrieval operations, and federal regulatory criteria is discussed. The monitoring system specified in this report is capable of measuring (1) package position and orientation, (2) vault deformation, (3) brine accumulation, (4) spent fuel dissolution, (5) temperature, (6) nuclear radiation, and (7) package condition with sufficient accuracy to provide data input to a general risk assessment model. In order to define a monitoring system which can provide probabilistic data on radiological risk to operating personnel and the general public for a salt mine repository, the following information is required: (1) a complete design of the salt SURF repository including inventory, density and waste package design details; (2) probalistic failure rate data on containment integrity of the SURF waste package; (3) probabilistic failure rate data on the monitoring system components
Design and Implementation of a Hybrid Ontological-Relational Data Repository for SIEM Systems

Directory of Open Access Journals (Sweden)

Igor Saenko

2013-07-01

Full Text Available The technology of Security Information and Event Management (SIEM becomes one of the most important research applications in the area of computer network security. The overall functionality of SIEM systems depends largely on the quality of solutions implemented at the data storage level, which is purposed for the representation of heterogeneous security events, their storage in the data repository, and the extraction of relevant data for analytical modules of SIEM systems. The paper discusses the key issues of design and implementation of a hybrid SIEM data repository, which combines relational and ontological data representations. Based on the analysis of existing SIEM systems and standards, the ontological approach is chosen as a core component of the repository, and an example of the ontological data model for vulnerabilities representation is outlined. The hybrid architecture of the repository is proposed for implementation in SIEM systems. Since the most of works on the repositories of SIEM systems is based on the relational data model, the paper focuses mainly on the ontological part of the hybrid approach. To test the repository we used the data model intended for attack modeling and security evaluation, which includes both ontological and relational dimensions.
Design perspectives for the low and intermediate level radioactive waste repository in Korea

International Nuclear Information System (INIS)

Kim, Young Ki; Koh, Kwang Hoon; Lee, Sang Sun; Lee, Byung Sik; Choi, Gi Won

2007-01-01

The underground waste repository is located at Gyeongju and is designed for the disposal of all the Low- and Intermediate Level Radioactive Waste(LILW). It is scheduled to commence operations in the beginning of 2009. The repository, with a disposal capacity of 800,000 drums, will be constructed in granite rock near the seashore at the Gyeongju site. The repository will be designed to be constructed in phases to reach its final capacity 800,000 drums. In the first phase of construction, the repository will have a capacity to store 100,000 drums. The repository will house all LILW generated in the Republic of Korea. The first phase of the repository design consists of an assess shaft, a construction tunnel, an operating tunnel, an unloading tunnel, and six(6) silos. The silos are located at 80 to 130 meters below Mean Sea level (MSL), in bedrock. Each silo is 24.8m in diameter and 52.4m in height. The silo will be reinforced with concrete lining for rock supports which will also act aas an engineered barrier in limiting radioactive nuclide release aft closure. After serving its intended function the repository will be filled and sealed. The primary objective of filling and sealing is to prevent ground water flow into the silo through the tunnel system and to prevent inadvertent intrusion into the repository after closure
Groundwater movements around a repository. Phase 1, State of the art and detailed study plan

International Nuclear Information System (INIS)

Lindblom, U.

1977-02-01

The report was prepared as the first phase of a study of the groundwater movements around a repository for spent nuclear fuel in the precambrian bedrock of Sweden. The objectives of these studies are to provide a state of the art review of groundwater slow in the region of a repository in granitic rock, in order to provide a basis for long term containment assessments and to prepare a detailed study plan for the continuation of the project. The different processes affecting the groundwater situation for containment are given. A state of the art review of the fluid flow, geochemical, heat transfer and rock mechanics processes as they relate to containment is presented. A detailed study plan to provide a comprehensive assessment of the hydrogeological regime around the repository during its lifetime is also presented. The groundwater flow fields will provide a basis for subsequent long term containment studies. (L.B.)
An integrated approach to isotopic study of crystalline rock for a high-level waste repository: Area phase

International Nuclear Information System (INIS)

Gilbert, L.A.

1986-01-01

An integrated approach to assessing isotopic systems in crystalline rock is planned for area phase studies. This approach combines radiogenic isotope systems with petrography in order to characterize potential crystalline repository media. The coeval use of selected isotope systems will minimize the limitations of each method and provide intensive parameters yielding data on alteration timing, secondary mineral formation, temperature history, and radionuclide species migration. Isotope systems will be selected in order to measure differences in sensitivity to thermal disturbances and mobility due to fluid interaction. Comparative evaluation of isotope pair behavior may be used in combination with mineral versus whole-rock dates to provide data on heating and mobilization of alkali elements, lanthanides, and gases, caused by future introduction of waste
Development of the design and reliability analysis of a seabed repository system

International Nuclear Information System (INIS)

1987-06-01

This study examines the seabed repository scheme proposed in 1979 for the long term disposal of heat generating radio-active waste and develops it to a standard sufficient to compare its reliability with the drilled emplacement and penetrator schemes. The reinforced concrete repositories contain 324 waste canisters and weigh 982 tonnes fully loaded in water. The repositories are transported up to 6000 km to the disposal area by a special purpose ship and lowered 5.5 km to the seabed on six braided nylon ropes by traction winches. Reliability of the seabed repository system, measured in terms of accidents per year involving loss of one or more canisters, was comparable with the other systems. (author)
Reference Design Description for a Geologic Repository

International Nuclear Information System (INIS)

2000-01-01

One of the current major national environmental problems is the safe disposal of large quantities of spent nuclear fuel and high-level radioactive waste materials, which are rapidly accumulating throughout the country. These radioactive byproducts are generated as the result of national defense activities and from the generation of electricity by commercial nuclear power plants. At present, spent nuclear fuel is accumulating at over 70 power plant sites distributed throughout 33 states. The safe disposal of these high-level radioactive materials at a central disposal facility is a high national priority. This Reference Design Description explains the current design for a potential geologic repository that may be located at Yucca Mountain in Nevada for the disposal of spent nuclear fuel and high-level radioactive waste materials. This document describes a possible design for the three fundamental parts of a repository: a surface facility, subsurface repository, and waste packaging. It also presents the current conceptual design of the key engineering systems for the final four phases of repository processes: operations, monitoring, closure, and postclosure. In accordance with current law, this design does not include an interim storage option. In addition, this Reference Design Description reviews the expected long-term performance of the potential repository. It describes the natural barrier system which, together with the engineered systems, achieves the repository objectives. This design will protect the public and the environment by allowing the safe disposal of radioactive waste received from government-owned custodial spent fuel sites, high-level radioactive waste sites, and commercial power reactor sites. All design elements meet or exceed applicable regulations governing the disposal of high-level radioactive waste. The design will provide safe disposal of waste materials for at least a 10,000 year period. During this time interval, natural radioactive decay
General construction requirements for the deep repository in the KBS-3 system

International Nuclear Information System (INIS)

2002-10-01

The KBS-3 systems includes equipment and plants for transport of spent nuclear fuels and encapsulated spent fuels, central intermediate storage, encapsulation and deep geologic disposal. The requirements in this document concern the repository and have been put together in view of the tasks of designing, constructing and building the repository. The report presents: A general review of existing design plans; Laws and regulations relevant for the design of the repository; How the regulations have been broken down to functional demands and dimensioning requirements for the repository; How the site conditions influence the design, and how the layout of the different parts of the repository interact; Relations between the functions of the repository, the safety and the design; A foundation for developing construction plans for the repository. The requirements will be collected in a database that will develop as new knowledge is collected
Geochemical modeling of the nuclear-waste repository system. A status report

International Nuclear Information System (INIS)

Deutsch, W.J.

1980-12-01

The primary objective of the geochemical modeling task is to develop an understanding of the waste-repository geochemical system and provide a valuable tool for estimating future states of that system. There currently exists a variety of computer codes which can be used in geochemical modeling studies. Some available codes contain the framework for simulating a natural chemical system and estimating, within limits, the response of that system to environmental changes. By data-base enhancement and code development, this modeling technique can be even more usefully applied to a nuclear-waste repository. In particular, thermodynamic data on elements not presently in the data base but identified as being of particular hazard in the waste-repository system, need to be incorporated into the code to estimate the near-field as well as the far-field reactions during a hypothetical breach. A reaction-path-simulation code, which estimates the products of specific rock/water reactions, has been tested using basalt and ground water. Results show that the mass-transfer capabilities of the code will be useful in chemical-evolution studies and scenario analyses. The purpose of this report is to explain the status of geochemical modeling as it currently applies to the chemical system of a hypothetical nuclear-waste repository in basalt and to present the plan proposed for further developmet and application
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
Data Storing Proposal from Heterogeneous Systems into a Specialized Repository

Directory of Open Access Journals (Sweden)

Václavová Andrea

2016-12-01

Full Text Available The aim of this paper is to analyze and to propose an appropriate system for processing and simultaneously storing a vast volume of structured and unstructured data. The paper consists of three parts. The first part addresses the issue of structured and unstructured data. The second part provides the detailed analysis of data repositories and subsequent evaluation indicating which system would be for the given type and volume of data optimal. The third part focuses on the use of gathered information to transfer data to the proposed repository.
Application of systems engineering to determine performance requirements for repository waste packages

International Nuclear Information System (INIS)

Aitken, E.A.; Stimmell, G.L.

1987-01-01

The waste package for a nuclear waste repository in salt must contribute substantially to the performance objectives defined by the Salt Repository Project (SRP) general requirements document governing disposal of high-level waste. The waste package is one of the engineered barriers providing containment. In establishing the performance requirements for a project focused on design and fabrication of the waste package, the systems engineering methodology has been used to translate the hierarchy requirements for the repository system to specific performance requirements for design and fabrication of the waste package, a subsystem of the repository. This activity is ongoing and requires a methodology that provides traceability and is capable of iteration as baseline requirements are refined or changed. The purpose of this summary is to describe the methodology being used and the way it can be applied to similar activities in the nuclear industry
An approach to improve Romanian geological repository planning

International Nuclear Information System (INIS)

Andrei, Veronica; Prisecaru, Ilie

2016-01-01

International standards recommend typical phases to be included within any national program for the development of a geological repository dedicated to disposal of the high level radioactive wastes generated in countries using nuclear power. However, these are not universally applicable and the content of each of these phases may need to be adapted for each national situation and regulatory and institutional framework. Several national geological repository programs have faced failures in schedules and have revised their programs to consider an adapted phased management approach. The authors have observed that in the case of those countries in the early phases of a geological repository program where boundary conditions have not been fully defined, international recommendations for handling delays/failures in the national program might not immediately help. This paper considers a case study of the influences of the national context risks on the current planning schedule of the Romanian national geological repository. It proposes an optimum solution for an integrated response to any significant adverse impact arising from these risks, enabling sustainable program planning

Monitoring during the stepwise implementation of the Swedish deep repository for spent fuel

Energy Technology Data Exchange (ETDEWEB)

Baeckblom, Goeran [Conrox (Sweden); Almen, Karl-Erik [KEA Geokonsult AB (Sweden)

2004-03-01

monitoring are to: obtain knowledge of undisturbed conditions in nature and their seasonal variations (baseline) in order to identify and evaluate the impact of activities related to the deep repository during different phases, obtain a better understanding of the function of the deep repository system to support the safety account and to test models and assumptions, monitor the environmental impact of the deep repository, provide evidence that the working environment is safe with regard to radiological and non-radiological effects, show that requirements on radioactive waste verification (safeguards) are fulfilled. The monitoring is concerned with bedrock conditions before and during construction and operation of the facilities, active design to engineer the underground facilities based on monitoring results during construction, the safe and environmental construction and operation of facilities. Experience exists from monitoring of the barrier function at SFR, the final repository for low - and intermediate level waste and at the Aespoe Hard Rock Laboratory and monitoring for safeguard at CLAB, the interim storage for spent nuclear fuel. The know-how on monitoring relates to all aspects from design, installation, operation and maintenance to decommissioning of systems. This report provides an overview of the features, processes and parameters that are collected during the site investigations to establish the Primary Baseline conditions for monitoring prior to the construction of the repository. It is also proposed that the monitoring programme should at least entail the following elements: objectives for the monitoring programme, scope for the monitoring (criteria for selection of issues to be monitored, identification of the properties, processes, phenomena and observable quantities to be monitored), identification on what methods to be used, operation of the monitoring system (identification of the duration and frequency of monitoring, including criteria for when
Integrated management system for radioactive waste repositories (SGI3R)

International Nuclear Information System (INIS)

Silva, Fabio; Tello, Cledola Cassia Oliveira de

2009-01-01

The implantation of a repository for radioactive wastes is a multidisciplinary project that needs specialists of different areas of knowledge, interaction with public and private institutions, data and information related to radioactive wastes, geology, technology etc. All the activities must be in accordance with norms, requirements and procedures, including national and international legislation. The maintenance of the waste inventory records is an important regulatory requirement and must be available even after the closure of the repository. CDTN - Center of Nuclear Technology Development - is coordinating the Project for the construction of the national repository to dispose the low -and intermediate-level wastes. In order to consolidate all information that will come from this Project, it is being developed and implanted in CDTN a manager system of database, called Integrated Management System for Radioactive Waste Repositories (SGI3R), which will also manage all data from previous work carried out in Brazil and around the world about this subject. The proposal is to build a structure of modules, having as base eight modules: inventory, site selection, types of repository, technology, partners, legislation, communication and documents. The SGI3R running comprises the data processing (inclusion, update and exclusion), integration, standardization, and consistency among the processes. The SGI3R will give support to the stages of this Project, which will allow the preservation of all the available information, preventing duplication of efforts and additional costs, improving, in this way, the Project planning and execution. Additionally the SGI3R will make possible the information access to all stakeholders. (author)
System analysis methods for geological repository of high level radioactive waste in granite

International Nuclear Information System (INIS)

Chen Weiming; Wang Ju; Li Yunfeng; Jin Yuanxin; Zhao Honggang

2009-01-01

Taking Beishan granite site as an example, this paper proposes the conceptual and structural design of repository for high level radioactive waste at first. Then the function, structure, environment and evolution of the repository are described by the methodology of system analysis. Based on these designs and descriptions, a calculation model for the repository is developed with software GoldSim. At last, this calculation model is applied to emulate the space-time distribution of repository radiotoxicity, to analyze the sensitivity of parameters in the model, to optimize the design parameters, and to predict and assess the repository performance. The results of this study can provide technical supports for resources allocation and coordination of R and D projects. (authors)
Development of database systems for safety of repositories for disposal of radioactive wastes

Energy Technology Data Exchange (ETDEWEB)

Lee, Yeong Hun; Han, Jeong Sang; Shin, Hyeon Jun; Ham, Sang Won; Kim, Hye Seong [Yonsei Univ., Seoul (Korea, Republic of)

1999-03-15

In the study, GSIS os developed for the maximizing effectiveness of the database system. For this purpose, the spatial relation of data from various fields that are constructed in the database which was developed for the site selection and management of repository for radioactive waste disposal. By constructing the integration system that can link attribute and spatial data, it is possible to evaluate the safety of repository effectively and economically. The suitability of integrating database and GSIS is examined by constructing the database in the test district where the site characteristics are similar to that of repository for radioactive waste disposal.
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
Monitoring during the stepwise implementation of the Swedish deep repository for spent fuel

International Nuclear Information System (INIS)

Baeckblom, Goeran; Almen, Karl-Erik

2004-03-01

to: obtain knowledge of undisturbed conditions in nature and their seasonal variations (baseline) in order to identify and evaluate the impact of activities related to the deep repository during different phases, obtain a better understanding of the function of the deep repository system to support the safety account and to test models and assumptions, monitor the environmental impact of the deep repository, provide evidence that the working environment is safe with regard to radiological and non-radiological effects, show that requirements on radioactive waste verification (safeguards) are fulfilled. The monitoring is concerned with bedrock conditions before and during construction and operation of the facilities, active design to engineer the underground facilities based on monitoring results during construction, the safe and environmental construction and operation of facilities. Experience exists from monitoring of the barrier function at SFR, the final repository for low - and intermediate level waste and at the Aespoe Hard Rock Laboratory and monitoring for safeguard at CLAB, the interim storage for spent nuclear fuel. The know-how on monitoring relates to all aspects from design, installation, operation and maintenance to decommissioning of systems. This report provides an overview of the features, processes and parameters that are collected during the site investigations to establish the Primary Baseline conditions for monitoring prior to the construction of the repository. It is also proposed that the monitoring programme should at least entail the following elements: objectives for the monitoring programme, scope for the monitoring (criteria for selection of issues to be monitored, identification of the properties, processes, phenomena and observable quantities to be monitored), identification on what methods to be used, operation of the monitoring system (identification of the duration and frequency of monitoring, including criteria for when monitoring may
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
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
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
Safety analysis of the post-operational phase

International Nuclear Information System (INIS)

Berg, H.P.; Ehrlich, D.

1991-01-01

The safety analysis of normal operation covers an analytical study of the system parts ultimate repository - waste forms of the ultimate repository system under normal and accidental operation. On that basis a requirement concept has been developed which entails reactions on planning and design of the repository, and requirements of waste products, packagings and permissible activities. The procedure for the operational phase is explained giving the Konrad repository project as an example. (DG) [de
Technical position on items and activities in the high-level waste geologic repository program subject to quality assurance requirements

International Nuclear Information System (INIS)

Duncan, A.B.; Bilhorn, S.G.; Kennedy, J.E.

1988-04-01

This document provides guidance on how to identify items and activities subject to Quality Assurance in the high-level nuclear waste repository program for pre-closure and post-closure phases of the repository. In the pre-closure phase, structures, systems and components essential to the prevention or mitigation of an accident that could result in an off-site radiation dose of 0.5rem or greater are termed ''important to safety''. In the post-closure phase, the barriers which are relied on to meet the containment and isolation requirements are defined as ''important to waste isolation''. These structures, systems, components, and barriers, and the activities related to their characterization, design, construction, and operation are required to meet quality assurance (QA) criteria to provide confidence in the performance of the geologic repository. The list of structures, systems, and components important to safety and engineered barriers important to waste isolation is referred to as the ''Q-List'' and lies within the scope of the QA program. 10 refs
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)
Safety analysis methodologies for radioactive waste repositories in shallow ground

International Nuclear Information System (INIS)

1984-01-01

The report is part of the IAEA Safety Series and is addressed to authorities and specialists responsible for or involved in planning, performing and/or reviewing safety assessments of shallow ground radioactive waste repositories. It discusses approaches that are applicable for safety analysis of a shallow ground repository. The methodologies, analysis techniques and models described are pertinent to the task of predicting the long-term performance of a shallow ground disposal system. They may be used during the processes of selection, confirmation and licensing of new sites and disposal systems or to evaluate the long-term consequences in the post-sealing phase of existing operating or inactive sites. The analysis may point out need for remedial action, or provide information to be used in deciding on the duration of surveillance. Safety analysis both general in nature and specific to a certain repository, site or design concept, are discussed, with emphasis on deterministic and probabilistic studies
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.
Interactions between mobilized radionuclides and secondary phases in final repository-relevant formation aquifers. Final report; Wechselwirkung mobilisierter Radionuklide mit sekundaeren Phasen in endlagerrelevanten Formationswaessern. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Curtius, H.; Kaiser, G.; Paparigas, Z.; Hansen, B.; Neumann, A.; Klinkenberg, M.; Mueller, E.; Bruecher, H.; Bosbach, D.

2010-10-15

The report on interactions between mobilized radionuclides and secondary phases in final repository-relevant formation aquifers covers the following issues: scope of study, leaching experiments, secondary phases, incorporation and sorption studies, summary and prospects. The results show that the investigated spent fuels dissolve instantaneously in contact with the repository-relevant aquifers in presence of iron ions. For the elements Cs and Sr no re-immobilization was observed. These elements have to be considered as mobile species in the radionuclide source term. The secondary phases due to corrosion processes are radionuclide sinks, i.e. actinides are re-immobilized, the retention mechanisms were clarified. The studies with irradiated nuclear fuel show that the uranium/silicon containing phases effect the molar solubility of actinides.
Demonstrating the sealing of a deep geologic repository: the RECAP project

International Nuclear Information System (INIS)

Kuzyk, G.W.; Dixon, D.A.; Martino, J.B.; Kozak, E.T.; Bilinsky, D.M.; Thompson, P.M.

2006-01-01

Atomic Energy of Canada Limited (AECL) has operated an Underground Research Laboratory (URL) for twenty-three years (1982-2005). The URL was designed and constructed to carry out in situ geotechnical R and D needed for the Canadian Nuclear Fuel Waste Management program. The facility is now being closed, the final of several phases that have included siting, site evaluation, construction and operation. The closure phase presents a unique opportunity to develop and demonstrate the methodologies needed for closure and site restoration of a deep geologic repository for used nuclear fuel. A wealth of technical background and characterization data, dating back to before the first excavation work was carried out, are available to support closure activities. A number of closure-related activities are being proposed as part of a REpository Closure And Post-closure (RECAP) project. The RECAP project is proposed to include demonstrations of shaft and borehole sealing and monitoring as well as fracture sealing (grouting), room closure and monitoring system decommissioning, all activities that would occur when closing an actual repository. In addition to the closure-related activities, the RECAP project could provide a unique opportunity to conduct intrusion-monitoring demonstrations as part of a repository safeguards demonstration. (author)
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
Simulation approaches for the two-phase flow in saline repositories using the code TOUGH2-GRS. Report in the frame of the project ZIESEL. Two-phase flow in a saline repository using the example ERAM; Ansaetze zur Simulation der Zweiphasenstroemung in salinaren Endlagern mit dem Code TOUGH2-GRS. Bericht im Vorhaben ZIESEL. Zweiphasenfluss in einem salinaren Endlager am Beispiel des ERAM

Energy Technology Data Exchange (ETDEWEB)

Navarro, Martin; Fischer, Heidemarie; Seher, Holger; Weyand, Torben

2016-10-15

The simulation approaches for the two-phase flow in saline repositories using the code TOUGH2-GRS cover the following issues: simulation of gravitational flows in horizontal galleries without vertical discretization, homogenization approach for the simulation of the two-phase flow in converging partly backfilled galleries, qualification of the convergence approach implemented by GRS into the code TOUGH2-GRS, discretization effects during replacement of liquid by gas, consequences for the system analyses in the frame of the project ZIESEL.
Concerns and issues for what to keep during the operational phase of repositories and how to keep it

International Nuclear Information System (INIS)

Nagy, Zoltan

2012-01-01

This presentation provided a detailed overview of pre-operational and operational data collection. Waste generation and pre-disposal waste management may precede the start of a planned, organized RWM program. Records Management System (RMS) should be developed as early as practicable. The importance of the early establishment of a coordinated, integrated and well managed information set was thus underlined. Information should be driven by the 'back end' of the waste management process, so that records required by the later stages are maintained throughout the earlier stages. RMSs should be systematic, given a high priority in the organisation and the ownership and responsibility of the RMS should be unambiguously clear. Each WM organisation should have a RMS group that oversees all phases of the RWL life cycle. A distinction was made between generations, pre-disposal, pre-operational and operational records. Highly relevant suggestions were given with regard to the content of the pre-operational and the operational phase, by specifying the following components: - The pre-operational phase of a repository: Planning records, Siting records, Design records, Licensing for construction records, Licensing for operation records; - The operational phase of a repository: Waste specific records, Facility and site specific records, General operational records, Closure related records. It was pointed out that we should consider both the long term retrievability and the long term usefulness of records. Reproducibility, transparency and traceability thus are important requirements. This underlines the importance of meta-data (e.g. not only measurement result but also with which measurement tool, who did the measurement and other information concerning the origin of the data). The term 'contextual data' was suggested as an alternative. Both terms require attention to the fact that creativity is needed to think about what a person with a completely different reference frame would
Update on the national low level radioactive waste repository study

International Nuclear Information System (INIS)

Veitch, S.M.

1997-01-01

Activity to establish a national repository for low-level and short-lived intermediate-level radioactive waste in Australia began in the early 1980's. From the early 1990's computer-based geographic information systems had developed sufficiently so that all of Australia could be quickly reviewed using digital data relevant to site selection criteria. A three-phased approach to site selection was commenced which included an iterative process of data collection, interpretation, and public involvement through discussion papers. All of Australia was reviewed using national-scale data, and eight broad regions were identified and reviewed using regional-scale data. A third phase report will be released shortly which includes details on the process for identifying the preferred region of the eight. This region will be the focus for public involvement and for detailed study to identify a site for the national repository

Malaysian Education Index (MEI): An Online Indexing and Repository System

Science.gov (United States)

Kabilan, Muhammad Kamarul; Ismail, Hairul Nizam; Yaakub, Rohizani; Yusof, Najeemah Mohd; Idros, Sharifah Noraidah Syed; Umar, Irfan Naufal; Arshad, Muhammad Rafie Mohd.; Idrus, Rosnah; Rahman, Habsah Abdul

2010-01-01

This "Project Sheet" describes an on-going project that is being carried out by a group of educational researchers, computer science researchers and librarians from Universiti Sains Malaysia, Penang. The Malaysian Education Index (MEI) has two main functions--(1) Online Indexing System, and (2) Online Repository System. In this brief…
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.
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.
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
The Format Converting/Transfer Agent and Repository System based on ebXML

Directory of Open Access Journals (Sweden)

KyeongRim Ahn

2004-12-01

Full Text Available As introducing XML in EC-environment, various document formats have been used due to XML characteristic. Also, other document format except XML have been used to exchange EC-related information. That is, as increasing trading partner, as increasing exchanged document format and business processing being complex. So, management difficulty and duplication problem happened as trading partners increasing. And, they want to change plural business workflow to general and uniform form as defining and arranging BP(Business Process. Therefore, in this paper, we define XML as future document standard agreement and discuss about service system architecture and Repository. Repository stores and manages document standard, information related to Business Processing, Messaging Profile, and so on. Repository structure is designed to cover various XML standards. Also, we design system to support ebXML communication protocol, MSH, as well as traditional communication protocol, such as X.25, X.400, etc. and implement to exchange information via FTP.
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
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...
SAFOD Phase III Core Sampling and Data Management at the Gulf Coast Repository

Directory of Open Access Journals (Sweden)

David Lockner

2011-03-01

Full Text Available The San Andreas Fault Observatory at Depth (SAFODproject is yielding new insight into the San Andreas Fault (Zoback et al., 2010; Zoback et al., this issue. SAFOD drilling started in 2002 with a pilot hole, and proceeded with three phrases of drilling and coring during the summers of 2004, 2005, and 2007 (Fig. 1. One key component of theproject is curation, sampling, and documentation of SAFOD core usage at the Integrated Ocean Drilling Program’s (IODP Gulf Coast Repository (GCR at Texas A&M University. We present here the milestones accomplished over the past two years of sampling Phase III core at the GCR.
The use of interaction matrices for identification, structuring and ranking of FEPs in a repository system. Application on the far-field of a deep geological repository for spent fuel

Energy Technology Data Exchange (ETDEWEB)

Skagius, K; Wiborgh, M [Kemakta, Stockholm (Sweden); Stroem, A [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

1995-11-01

The basic device in the Rock Engineering Systems approach, the interaction matrix, has been used to identify, structure and rank Features, Events, and Processes (FEPs) describing barrier performance and radionuclide behaviour in the far-field of a deep geologic repository for spent fuel. The result is a first version of the Process System (PS), for the far-field of a deep repository, structured in an interaction matrix with supporting documentation. The documentation is compiled in databases, one containing matrix specific information and one containing general FEP descriptions. The study has shown that an interaction matrix is feasible to use both for the structuring of the PS and for visualisation of the PS. The developed documentation system increases the transparency of the system description and makes it possible to trace back the judgements made during the construction of the matrix. This will facilitate review work and future revisions as well as consistent treatment of different issues in the system. This study is a first step in the application of a systematic method to establish a structured description of the PS for a deep repository for spent fuel. The work could be seen as a part of the preparation for the forthcoming performance and safety analysis. The next step would be to develop the PS for the remaining parts of the repository system to the same level as has been done for the far-field system. Before the PS is evaluated for different selected system premises, a scientific review of the contents of the PS for the whole repository system would be beneficial. 5 refs.
The use of interaction matrices for identification, structuring and ranking of FEPs in a repository system. Application on the far-field of a deep geological repository for spent fuel

International Nuclear Information System (INIS)

Skagius, K.; Wiborgh, M.; Stroem, A.

1995-11-01

The basic device in the Rock Engineering Systems approach, the interaction matrix, has been used to identify, structure and rank Features, Events, and Processes (FEPs) describing barrier performance and radionuclide behaviour in the far-field of a deep geologic repository for spent fuel. The result is a first version of the Process System (PS), for the far-field of a deep repository, structured in an interaction matrix with supporting documentation. The documentation is compiled in databases, one containing matrix specific information and one containing general FEP descriptions. The study has shown that an interaction matrix is feasible to use both for the structuring of the PS and for visualisation of the PS. The developed documentation system increases the transparency of the system description and makes it possible to trace back the judgements made during the construction of the matrix. This will facilitate review work and future revisions as well as consistent treatment of different issues in the system. This study is a first step in the application of a systematic method to establish a structured description of the PS for a deep repository for spent fuel. The work could be seen as a part of the preparation for the forthcoming performance and safety analysis. The next step would be to develop the PS for the remaining parts of the repository system to the same level as has been done for the far-field system. Before the PS is evaluated for different selected system premises, a scientific review of the contents of the PS for the whole repository system would be beneficial. 5 refs
Records for radioactive waste management up to repository closure: Managing the primary level information (PLI) set

International Nuclear Information System (INIS)

2004-07-01

The objective of this publication is to highlight the importance of the early establishment of a comprehensive records system to manage primary level information (PLI) as an integrated set of information, not merely as a collection of information, throughout all the phases of radioactive waste management. Early establishment of a comprehensive records system to manage Primary Level Information as an integrated set of information throughout all phases of radioactive waste management is important. In addition to the information described in the waste inventory record keeping system (WIRKS), the PLI of a radioactive waste repository consists of the entire universe of information, data and records related to any aspect of the repository's life cycle. It is essential to establish PLI requirements based on integrated set of needs from Regulators and Waste Managers involved in the waste management chain and to update these requirements as needs change over time. Information flow for radioactive waste management should be back-end driven. Identification of an Authority that will oversee the management of PLI throughout all phases of the radioactive waste management life cycle would guarantee the information flow to future generations. The long term protection of information essential to future generations can only be assured by the timely establishment of a comprehensive and effective RMS capable of capturing, indexing and evaluating all PLI. The loss of intellectual control over the PLI will make it very difficult to subsequently identify the ILI and HLI information sets. At all times prior to the closure of a radioactive waste repository, there should be an identifiable entity with a legally enforceable financial and management responsibility for the continued operation of a PLI Records Management System. The information presented in this publication will assist Member States in ensuring that waste and repository records, relevant for retention after repository closure
Geohydrological simulation of a deep coastal repository

International Nuclear Information System (INIS)

Follin, S.

1995-12-01

This conceptual-numerical study treats the dewatering and resaturation phases associated with the construction, use and closure of a coastal nuclear waste repository located at depth in sparsely fractured Baltic Shield rocks. The main objective is to simulate the extent and duration of saline intrusion for a reasonable set of geohydrological assumptions. Long-term changes in the chemical environment associated with saline intrusion may affect the properties of the buffer zone material (bentonite). The first part of the study deals with history matching of a simple model geometry and the second part treats the dewatering and resaturation phases of the simulated repository. The history matching supports the standpoint that the occurrence of saline ground water reflects an ongoing but incomplete Holocene flushing of the Baltic Shield. The drawdown after fifty years of dewatering is highly dependent on the permeability of the excavated damaged zone. If the permeability close the repository is unaltered the entire region between the top side of the model and the repository is more or less partially saturated at the end of the simulation period. The simulations of a fifty year long recovery period suggest that the distribution between fresh and saline ground waters may be quite close to the conditions prior to the dewatering phase already after fifty years of closure despite an incomplete pressure recovery, which is an interesting result considering the objective of the study. 12 refs
Project Guarantee 1985. Final repository for high-level radioactive wastes: The system of safety barriers

International Nuclear Information System (INIS)

Anon.

1985-01-01

Final disposal of radioactive waste involves preventing the waste from returning from the repository location into the biosphere by means of successively arranged containment measures known as safety barriers. In the present volume NGB 85-04 of the series of reports for Project 'Guarantee' 1985, the safety barrier system for the type C repository for high-level waste is described. The barrier parameters which are relevant for safety analysis are quantified and associated error limits and data scatter are given. The aim of the report is to give a summary documentation of the safety analysis input data and their scientific background. For secure containment of radioactive waste safety barriers are used which effectively limit the release of radioactive material from the repository (release barriers) and effectively retard the entry of the original radioactive material into the biosphere (time barriers). Safety barriers take the form of both technically constructed containment measures and the siting of the repository in suitable geological formations. The technical safety barrier system in the case of high-level waste comprises: the waste solidification matrix (borosilicate glass), massive steel canisters, encasement of the waste canisters, encasement of the waste canisters in highly compacted bentonite, sealing of vacant storage space and access routes on repository closure. The natural geological safety barriers - the host rock and overlying formations provide sufficiently long deep groundwater flow times from the repository location to the earth's surface and for additional lengthening of radionuclide migration times by means of various chemical and physical retardation mechanisms. The stability of the geological formations is so great that hydrogeological system is protected for a sufficient length of time from deterioration caused, in particular, by erosion. Observations in the final section of the report indicate that input data for the type C repository safety
Siting Process for HLW Repository in Japan

International Nuclear Information System (INIS)

Masuda, S.; Kitayama, K.; Umeki, H.; Naito, M.

2002-01-01

In the year 2000, the geological disposal program for high-level radioactive waste in Japan moved from the phase of generic research and development (R and D) into the phase of implementation. Following legislation entitled the ''Specified Radioactive Waste Final Disposal Act'', the Nuclear Waste Management Organization of Japan (NUMO) was established as the implementing organization. The assigned activities of NUMO include selection of the repository site, demonstration of disposal technology at the site, developing relevant licensing applications and construction, operation and closure of the repository. As the first milestone of siting process, NUMO announced to the public an overall procedure for selection of preliminary investigation areas for potential candidate sites on October 29, 2001. The procedure specifies that NUMO will solicit volunteer municipalities for preliminary investigation areas with publishing four documents as an information package. These documents are tentatively entitled ''Instructions for Application'', ''Siting Factors for the Preliminary Investigation Areas'', a ''Repository Concepts'' as well as an ''Site Investigation Community Outreach Scheme''
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
Analysis of stresses on the 1st phase support of the monitoring drifts of the radioactive waste repository

Directory of Open Access Journals (Sweden)

Hatala Jozef

1999-09-01

Full Text Available In the paper, the stability analysis of the radioactive waste repository monitoring drifts support by means of the numerical modelling - finite element method is described. The aim of this analysis was to judge to what extent the designed 1st phase supports parameters correspond with the geomechanical conditions determined by the engineering-geological survey.
Reference Design Description for a Geologic Repository, Rev. 03, ICN 02

International Nuclear Information System (INIS)

Gerald Shideler

2001-01-01

One of the current major national environmental problems is the safe disposal of large quantities of spent nuclear fuel and high-level radioactive waste materials, which are rapidly accumulating throughout the country. These radioactive byproducts are generated as the result of national defense activities and from the generation of electricity by commercial nuclear power plants. At present, spent nuclear fuel is accumulating at over 70 power plant sites distributed throughout 33 states. The safe disposal of these high-level radioactive materials at a central disposal facility is a high national priority. This Reference Design Description explains the current design for a potential geologic repository that may be located at Yucca Mountain in Nevada for the disposal of spent nuclear fuel and high-level radioactive waste materials. This document describes a possible design for the three fundamental parts of a repository: a surface facility, subsurface repository, and waste packaging. It also presents the current conceptual design of the key engineering systems for the final four phases of repository processes: operations, monitoring, closure, and postclosure. In accordance with current law, this design does not include an interim storage option. In addition, this Reference Design Description reviews the expected long-term performance of the potential repository. It describes the natural barrier system which, together with the engineered systems, achieves the repository objectives. This design will protect the public and the environment by allowing the safe disposal of radioactive waste received from government-owned custodial spent fuel sites, high-level radioactive waste sites, and commercial power reactor sites. All design elements meet or exceed applicable regulations governing the disposal of high-level radioactive waste. The design will provide safe disposal of waste materials for at least a 10,000 year period. During this time interval, natural radioactive decay
Project Guarantee 1985. Final repository for low- and intermediate-level radioactive wastes: The system of safety barriers

International Nuclear Information System (INIS)

Anon.

1985-01-01

The safety barrier system for the type B repository for low- and intermediate-level waste is described. The barrier parameters which are relevant for safety analysis are quantified and associated error limits and data scatter are given. The aim of the report is to give a summary documentation of the safety analysis input data and their scientific background. For secure containment of radioactive waste safety barriers are used which effectively limit the release of radioactive material from the repository (release barriers) and effectively retard the entry of the original radioactive material into the biosphere (time barriers). In the case of low- and intermediate-level waste the technical safety barrier system comprises: waste solidification matrix (cement, bitumen and resin), immobilisation of the waste packages in containers using liquid cement, concrete repository containers, backfilling of remaining vacant storage space with special concrete, concrete lining of the repository caverns, sealing of access tunnels on final closure of the repository. Natural geological safety barriers - host rock and overlying formations - have the following important functions. Because of its stability, the host rock in the repository zone protects the technical safety barrier system from destruction caused by climatic effects and erosion for a sufficient length of time. It also provides for low water flow and favourable chemistry (reducing conditions)
A GoldSim modeling approach to safety assessment of an LILW repository system

International Nuclear Information System (INIS)

Lee, Youn Myoung; Jeong, Jongtae; Choi, Jongwon

2011-01-01

A program for the safety assessment and performance evaluation of a low- and intermediate level waste (LILW) repository system has been developed by utilizing GoldSim. By utilizing this nuclide transport in the near- and far-field of a repository as well as a transport through a biosphere under various natural and manmade disruptive events affecting a nuclide release are modeled and evaluated. To demonstrate its usability, some illustrative cases under the selected scenarios including the influence of degradation of manmade barriers, pumping well drilling, and the natural disruptive events such as a sudden formation of preferential flow pathway have been investigated and illustrated for a hypothetical LILW repository. Even though all the parameter values applied to a hypothetical repository are assumed without any real base, the illustrative cases could be informative especially when seeing the result of the probabilistic calculation or sensitivity studies with various scenarios that possibly happen for nuclide release and further transport. (author)
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

JSS project phase 4: Experimental and modelling studies of HLW glass dissolution in repository environments

International Nuclear Information System (INIS)

1987-10-01

A goal of the JSS project was to develop a scientific basis for understanding the effects of waste package components, groundwater chemistry, and other repository conditions on glass dissolution behaviour, and to develop and refine a model for the processes governing glass dissolution. The fourth phase of the project, which was performed by the Hahn-Meitner-Institut, Berlin, FRG, dealt specifically with model development and application. Phase 4 also adressed whether basaltic glasses could serve as natural analogues for nuclear waste glasses, thus providing a means to test the capability of the model for long-term predictions. Additional experiments were performed in order to complete the data base necessary to model interactions between the glass and bentonite and between glass and steel corrosion products. More data on temperature, S/V, and pH dependence of the glass/water reaction were also collected. In this report, the data acquired during phase 4 are presented and discussed. (orig./DG)
System studies in PA: Development of process influence diagram (PID) for SFR-1 repository near-field + far-field

International Nuclear Information System (INIS)

Stenhouse, M.J.; Miller, W.M.; Chapman, N.A.

2001-05-01

Scenario development is a key component of the performance assessment (PA) process for radioactive waste disposal, the primary objective being to ensure that all relevant factors associated with the future evolution of the repository system are properly considered in PA. As part of scenario development, a list of features, events and processes (FEPs) are identified and assembled, representing the Process System, with interactions/influences between FEPs incorporated in a Process Influence Diagram (PID). This report documents the technical work conducted between 1997 and the end of 1999 under the Systems Studies Project. The overall objective of this project has been the construction of a PID for the SFR-1 repository (final repository for reactor waste), this PID being the first stage in the identification of scenarios to describe future evolution of this repository. The PIDs discussed in this report have been created using two software applications: existing commercial software (Business Modeller, Infotool AB. Stockholm, Sweden) and, more recently, a newly developed software tool SPARTA (Enviros QuantiSci, Henley, U.K.). Although the focus of this report is on the application of SPARTA to PID development, it is important to document the work carried out prior to SPARTA being available, in order to provide a complete record of the entire SFR-1 PID development effort as well as preserving the context of the multi-year project. Following a description of the different disposal sections of the SFR-1 and the various near-field barriers, the sequential development (i.e. near-field of Silo, BMA, BLA, BTF sections; far-field; integrated near-field + far-field) of the PID for SFR-1 repository system using Business Modeller is described. Owing to the complexity of the repository, in terms of number of both different disposal sections (Silo, BLA, BMA, BTF) and barriers associated with each section, the two-dimensional (2D) PID created for SFR-1 using Business Modeller is
Uncertainty and sensitivity analysis for two-phase flow in the vicinity of the repository in the 1996 performance assessment for the Waste Isolation Pilot Plant: Disturbed conditions

International Nuclear Information System (INIS)

HELTON, JON CRAIG; BEAN, J.E.; ECONOMY, K.; GARNER, J.W.; MACKINNON, ROBERT J.; MILLER, JOEL D.; SCHREIBER, J.D.; VAUGHN, PALMER

2000-01-01

Uncertainty and sensitivity analysis results obtained in the 1996 performance assessment (PA) for the Waste Isolation Pilot Plant (WIPP) are presented for two-phase flow in the vicinity of the repository under disturbed conditions resulting from drilling intrusions. Techniques based on Latin hypercube sampling, examination of scatterplots, stepwise regression analysis, partial correlation analysis and rank transformations are used to investigate brine inflow, gas generation repository pressure, brine saturation and brine and gas outflow. Of the variables under study, repository pressure and brine flow from the repository to the Culebra Dolomite are potentially the most important in PA for the WIPP. Subsequent to a drilling intrusion repository pressure was dominated by borehole permeability and generally below the level (i.e., 8 MPa) that could potentially produce spallings and direct brine releases. Brine flow from the repository to the Culebra Dolomite tended to be small or nonexistent with its occurrence and size also dominated by borehole permeability
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.
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
An Open Challenge Problem Repository for Systems Supporting Binders

OpenAIRE

Felty, A.; Momigliano, A.; Pientka, B.

2015-01-01

A variety of logical frameworks support the use of higher-order abstract syntax in representing formal systems; however, each system has its own set of benchmarks. Even worse, general proof assistants that provide special libraries for dealing with binders offer a very limited evaluation of such libraries, and the examples given often do not exercise and stress-test key aspects that arise in the presence of binders. In this paper we design an open repository ORBI (Open challenge problem Repo...
MRS system study for the repository: Yucca Mountain Site Characterization Project

International Nuclear Information System (INIS)

Sinagra, T.A.; Harig, R.

1990-12-01

The US Department of Energy (DOE), Office of Civilian Radioactive Waste Management (OCRWM), has initiated a waste management system study to identify the impacts of the presence or absence of a monitored retrievable storage facility (hereinafter referred to as ''MRS'') on system costs and program schedules. To support this study, life-cycle cost estimates and construction schedules have been prepared for the surface and underground facilities and operations geologic nuclear waste repository at Yucca Mountain, Nye County, Nevada. Nine different operating scenarios (cases) have been identified by OCRWM for inclusion in this study. For each case, the following items are determined: the repository design and construction costs, operating costs, closure and decommissioning costs, required staffing, construction schedules, uncertainties associated with the costs and schedules, and shipping cask and disposal container throughputs. This document contains A-D
MRS system study for the repository: Yucca Mountain Site Characterization Project

International Nuclear Information System (INIS)

Sinagra, T.A.; Harig, R.

1990-12-01

The US Department of Energy (DOE), Office of Civilian Radioactive Waste Management (OCRWM), has initiated a waste management system study to identify the impacts of the presence or absence of a monitored retrievable storage facility (hereinafter referred to as ''MRS'') on system costs and program schedules. To support this study, life-cycle cost estimates and construction schedules have been prepared for the surface and underground facilities and operations of a geologic nuclear waste repository at Yucca Mountain, Nye County, Nevada. Nine different operating scenarios (cases) have been identified by OCRWM for inclusion in this study. For each case, the following items are determined: the repository design and construction costs, operating costs, closure and decommissioning costs, required staffing, construction schedules, uncertainties associated with the costs and schedules, and shipping cask and disposal container throughputs. 6 refs., 83 figs., 57 tabs
The Age-ility Project (Phase 1): Structural and functional imaging and electrophysiological data repository.

Science.gov (United States)

Karayanidis, Frini; Keuken, Max C; Wong, Aaron; Rennie, Jaime L; de Hollander, Gilles; Cooper, Patrick S; Ross Fulham, W; Lenroot, Rhoshel; Parsons, Mark; Phillips, Natalie; Michie, Patricia T; Forstmann, Birte U

2016-01-01

Our understanding of the complex interplay between structural and functional organisation of brain networks is being advanced by the development of novel multi-modal analyses approaches. The Age-ility Project (Phase 1) data repository offers open access to structural MRI, diffusion MRI, and resting-state fMRI scans, as well as resting-state EEG recorded from the same community participants (n=131, 15-35 y, 66 male). Raw imaging and electrophysiological data as well as essential demographics are made available via the NITRC website. All data have been reviewed for artifacts using a rigorous quality control protocol and detailed case notes are provided. Copyright © 2015. Published by Elsevier Inc.
The Tropical and Subtropical Germplasm Repositories of The National Germplasm System

Science.gov (United States)

Germplasm collections are viewed as a source of genetic diversity to support crop improvement and agricultural research, and germplasm conservation efforts. The United States Department of Agriculture's National Plant Germplasm Repository System (NPGS) is responsible for administering plant genetic ...
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
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
Classifying Clinical Trial Eligibility Criteria to Facilitate Phased Cohort Identification Using Clinical Data Repositories.

Science.gov (United States)

Wang, Amy Y; Lancaster, William J; Wyatt, Matthew C; Rasmussen, Luke V; Fort, Daniel G; Cimino, James J

2017-01-01

A major challenge in using electronic health record repositories for research is the difficulty matching subject eligibility criteria to query capabilities of the repositories. We propose categories for study criteria corresponding to the effort needed for querying those criteria: "easy" (supporting automated queries), mixed (initial automated querying with manual review), "hard" (fully manual record review), and "impossible" or "point of enrollment" (not typically in health repositories). We obtained a sample of 292 criteria from 20 studies from ClinicalTrials.gov. Six independent reviewers, three each from two academic research institutions, rated criteria according to our four types. We observed high interrater reliability both within and between institutions. The analysis demonstrated typical features of criteria that map with varying levels of difficulty to repositories. We propose using these features to improve enrollment workflow through more standardized study criteria, self-service repository queries, and analyst-mediated retrievals.
Application of geostatistical methods to long-term safety analyses for radioactive waste repositories

International Nuclear Information System (INIS)

Roehlig, K.J.

2001-01-01

Long-term safety analyses are an important part of the design and optimisation process as well as of the licensing procedure for final repositories for radioactive waste in deep geological formations. For selected scenarios describing possible evolutions of the repository system in the post-closure phase, quantitative consequence analyses are performed. Due to the complexity of the phenomena of concern and the large timeframes under consideration, several types of uncertainties have to be taken into account. The modelling work for the far-field (geosphere) surrounding or overlaying the repository is based on model calculations concerning the groundwater movement and the resulting migration of radionuclides which possibly will be released from the repository. In contrast to engineered systems, the geosphere shows a strong spatial variability of facies, materials and material properties. The paper presented here describes the first steps towards a quantitative approach for an uncertainty assessment taking into account this variability. Due to the availability of a large amount of data and information of several types, the Gorleben site (Germany) has been used for a case study in order to demonstrate the method. (orig.)
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...
Active geothermal systems as natural analogs of HLW repositories

International Nuclear Information System (INIS)

Elders, W.A.; Williams, A.E.; Cohen, L.H.

1988-01-01

Geologic analogs of long-lived processes in high-level waste (HLW) repositories have been much studied in recent years. However, most of these occurrences either involve natural processes going on today at 25 degree C, or, if they are concerned with behavior at temperatures similar to the peak temperatures anticipated near HLW canisters, have long since ended. This paper points out the usefulness of studying modern geothermal systems as natural analogs, and to illustrate the concept with a dramatic example, the Salton Sea geothermal system (SSGS)
A data library management system for midwest FreightView and its data repository.

Science.gov (United States)

2011-03-01

Midwest FreightView (MWFV) and its associated data repository is part of a large multifaceted : effort to promote regional economic development throughout the Great Lakes : system. The main objective for the system is to promote sustainable maritime ...
Interoperability Across the Stewardship Spectrum in the DataONE Repository Federation

Science.gov (United States)

Jones, M. B.; Vieglais, D.; Wilson, B. E.

2016-12-01

Thousands of earth and environmental science repositories serve many researchers and communities, each with their own community and legal mandates, sustainability models, and historical infrastructure. These repositories span the stewardship spectrum from highly curated collections that employ large numbers of staff members to review and improve data, to small, minimal budget repositories that accept data caveat emptor and where all responsibility for quality lies with the submitter. Each repository fills a niche, providing services that meet the stewardship tradeoffs of one or more communities. We have reviewed these stewardship tradeoffs for several DataONE member repositories ranging from minimally (KNB) to highly curated (Arctic Data Center), as well as general purpose (Dryad) to highly discipline or project specific (NEON). The rationale behind different levels of stewardship reflect resolution of these tradeoffs. Some repositories aim to encourage extensive uptake by keeping processes simple and minimizing the amount of information collected, but this limits the long-term utility of the data and the search, discovery, and integration systems that are possible. Other repositories require extensive metadata input, review, and assessment, allowing for excellent preservation, discovery, and integration but at the cost of significant time for submitters and expense for curatorial staff. DataONE recognizes these different levels of curation, and attempts to embrace them to create a federation that is useful across the stewardship spectrum. DataONE provides a tiered model for repositories with growing utility of DataONE services at higher tiers of curation. The lowest tier supports read-only access to data and requires little more than title and contact metadata. Repositories can gradually phase in support for higher levels of metadata and services as needed. These tiered capabilities are possible through flexible support for multiple metadata standards and services
Materials Degradation Issues in the U.S. High-Level Nuclear Waste Repository

Energy Technology Data Exchange (ETDEWEB)

K.G. Mon; F. Hua

2005-04-12

This paper reviews the state-of-the-art understanding of the degradation processes by the Yucca Mountain Project (YMP) with focus on interaction between the in-drift environmental conditions and long-term materials degradation of waste packages and drip shields within the repository system during the first 10,000-years after repository closure. This paper provides an overview of the degradation of the waste packages and drip shields in the repository after permanent closure of the facility. The degradation modes discussed in this paper include aging and phase instability, dry oxidation, general and localized corrosion, stress corrosion cracking, and hydrogen induced cracking of Alloy 22 and titanium alloys. The effects of microbial activity and radiation on the degradation of Alloy 22 and titanium alloys are also discussed. Further, for titanium alloys, the effects of fluorides, bromides, and galvanic coupling to less noble metals are considered. It is concluded that the materials and design adopted will provide sufficient safety margins for at least 10,000-years after repository closure.
Materials Degradation Issues in the U.S. High-Level Nuclear Waste Repository

International Nuclear Information System (INIS)

Mon, K.G.; Hua, F.

2005-01-01

This paper reviews the state-of-the-art understanding of the degradation processes by the Yucca Mountain Project (YMP) with focus on interaction between the in-drift environmental conditions and long-term materials degradation of waste packages and drip shields within the repository system during the first 10,000-years after repository closure. This paper provides an overview of the degradation of the waste packages and drip shields in the repository after permanent closure of the facility. The degradation modes discussed in this paper include aging and phase instability, dry oxidation, general and localized corrosion, stress corrosion cracking, and hydrogen induced cracking of Alloy 22 and titanium alloys. The effects of microbial activity and radiation on the degradation of Alloy 22 and titanium alloys are also discussed. Further, for titanium alloys, the effects of fluorides, bromides, and galvanic coupling to less noble metals are considered. It is concluded that the materials and design adopted will provide sufficient safety margins for at least 10,000-years after repository closure

Considerations for developing seismic design criteria for nuclear waste storage repositories

International Nuclear Information System (INIS)

Owen, G.N.; Yanev, P.I.; Scholl, R.E.

1980-04-01

The function of seismic design criteria is to reduce the potential for hazards that may arise during various stages of the repository life. During the operational phase, the major concern is with the possible effects of earthquakes on surface facilities, underground facilities, and equipment. During the decommissioned phase, the major concern is with the potential effects of earthquakes on the geologic formation, which may result in a reduction in isolation capacity. Existing standards and guides or criteria used for the static and seismic design of licensed nuclear facilities were reviewed and evaluated for their applicability to repository design. This report is directed mainly toward the development of seismic design criteria for the underground structures of repositories. An initial step in the development of seismic design criteria for the underground structures of repositories is the development of performance criteria, or minimum standards of acceptable behavior. A number of possible damage modes are identified for the operating phase of the repository; however, no damage modes are foreseen that would perturb the long-term function of the repository, except for the possibility of increased permeability within the rock mass. Subsequent steps in formulating acceptable seismic design criteria for the underground structures involve the quantification of the design process. The report discusses the necessity of specifying the form of ground motion that would be needed for seismic analysis and the procedures that may be used for making ground motion predictions. Further discussions outline what is needed for analysis, including rock properties, failure criteria, modeling techniques, seismic hardening criteria for the host rock mass, and probabilistic considerations
Quality assurance records system for research and development activities in support of geologic repository programs

International Nuclear Information System (INIS)

Smith, J.W.; Ryder, D.E.

1987-01-01

The Pacific Northwest Laboratory (PNL), which is operated by Battelle Memorial Institute for the Department of Energy, is conducting site-specific research for all three candidate sites for the first geologic high-level waste repository, as well as generic research for the second repository. In conjunction with this effort, PNL has developed a quality assurance (QA) program that is applicable to all organizations that are performing research and development (R and D) activities in support of the repository programs. This QA program meets the basic and supplemental requirements of ANSI/ASME NQA-1-1983 and the Nuclear Regulatory Commission (NRC) Review Plan for QA Programs for Site Characterization of High Level Nuclear Waste Repositories. A key part of this program is the handling of QA records that may ultimately support the licensing process for the repository. This paper describes a QA records system that is flexible enough to accommodate several types of research, such as paper studies, test method development, site characterization studies, software development, and hardware design. In addition, the QA records system is acceptable to a variety of sponsors who have licensing concerns. The QA procedures and their relation to the requirements are described. Most important is the discussion on the approaches used to assure that the records are organized such that the user can readily recreate or defend data, conclusions, and recommendations resulting from the research
System studies in PA: Development of process influence diagram (PID) for SFR-1 repository near-field + far-field

Energy Technology Data Exchange (ETDEWEB)

Stenhouse, M.J. [Monitor Scientific, LLC, Denver, CO (United States); Miller, W.M.; Chapman, N.A. [QuantiSci Ltd., Melton Mowbray (United Kingdom)

2001-05-01

Scenario development is a key component of the performance assessment (PA) process for radioactive waste disposal, the primary objective being to ensure that all relevant factors associated with the future evolution of the repository system are properly considered in PA. As part of scenario development, a list of features, events and processes (FEPs) are identified and assembled, representing the Process System, with interactions/influences between FEPs incorporated in a Process Influence Diagram (PID). This report documents the technical work conducted between 1997 and the end of 1999 under the Systems Studies Project. The overall objective of this project has been the construction of a PID for the SFR-1 repository (final repository for reactor waste), this PID being the first stage in the identification of scenarios to describe future evolution of this repository. The PIDs discussed in this report have been created using two software applications: existing commercial software (Business Modeller, Infotool AB. Stockholm, Sweden) and, more recently, a newly developed software tool SPARTA (Enviros QuantiSci, Henley, U.K.). Although the focus of this report is on the application of SPARTA to PID development, it is important to document the work carried out prior to SPARTA being available, in order to provide a complete record of the entire SFR-1 PID development effort as well as preserving the context of the multi-year project. Following a description of the different disposal sections of the SFR-1 and the various near-field barriers, the sequential development (i.e. near-field of Silo, BMA, BLA, BTF sections; far-field; integrated near-field + far-field) of the PID for SFR-1 repository system using Business Modeller is described. Owing to the complexity of the repository, in terms of number of both different disposal sections (Silo, BLA, BMA, BTF) and barriers associated with each section, the two-dimensional (2D) PID created for SFR-1 using Business Modeller is
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)
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
An evaluation of repository-induced disturbances for a KBS-3 type repository

Energy Technology Data Exchange (ETDEWEB)

Savage, D.; McLeod, R.; McEwen, T. [QuantiSci, Melton Mowbray (United Kingdom)

1998-03-01

This report considers the potential physical and chemical perturbations caused by the excavation, operation and backfilling and sealing of a KBS-3 type repository for spent fuel in Sweden. Parts of the underground excavations are likely to remain open to the atmosphere for up to several decades. Time-dependent changes to the chemical environment and the properties of the geological formation will be occurring as well as the initial disturbance of construction and subsequent changes after backfilling. In addition, this report also discusses issues that arise from the co-disposal of spent fuel and intermediate level waste. The processes which are likely to act during each stage of a repository from construction through to backfilling and sealing have been reviewed and the degree to which these processes are understood and represented within the performance assessment is discussed. The areas of particular interest are: The coupling of thermal, hydrogeological and mechanical processes with particular reference to the development of the near-field; Understanding the transient process of re-saturation with particular reference to the buffer material surrounding the waste canisters, including chemical changes to the material; The impact of accidental events during the construction and operational phases of work and their possible consequence on the long term performance of the repository; Chemical issues relating to the co-disposal of spent fuel and intermediate level wastes within a single facility. When consideration of transient processes and coupling is discussed, it is apparent that numerical tools and a complete understanding to provide quantitative information is lacking. The importance of the engineered barrier system within the performance assessment for spent fuel disposal is recognised and the emphasis is placed on the understanding of the coupled processes in the evolution in the near-field of the geosphere 45 refs, 4 fig, 2 tabs
An evaluation of repository-induced disturbances for a KBS-3 type repository

International Nuclear Information System (INIS)

Savage, D.; McLeod, R.; McEwen, T.

1998-03-01

This report considers the potential physical and chemical perturbations caused by the excavation, operation and backfilling and sealing of a KBS-3 type repository for spent fuel in Sweden. Parts of the underground excavations are likely to remain open to the atmosphere for up to several decades. Time-dependent changes to the chemical environment and the properties of the geological formation will be occurring as well as the initial disturbance of construction and subsequent changes after backfilling. In addition, this report also discusses issues that arise from the co-disposal of spent fuel and intermediate level waste. The processes which are likely to act during each stage of a repository from construction through to backfilling and sealing have been reviewed and the degree to which these processes are understood and represented within the performance assessment is discussed. The areas of particular interest are: The coupling of thermal, hydrogeological and mechanical processes with particular reference to the development of the near-field; Understanding the transient process of re-saturation with particular reference to the buffer material surrounding the waste canisters, including chemical changes to the material; The impact of accidental events during the construction and operational phases of work and their possible consequence on the long term performance of the repository; Chemical issues relating to the co-disposal of spent fuel and intermediate level wastes within a single facility. When consideration of transient processes and coupling is discussed, it is apparent that numerical tools and a complete understanding to provide quantitative information is lacking. The importance of the engineered barrier system within the performance assessment for spent fuel disposal is recognised and the emphasis is placed on the understanding of the coupled processes in the evolution in the near-field of the geosphere
Distributed Web Service Repository

Directory of Open Access Journals (Sweden)

Piotr Nawrocki

2015-01-01

Full Text Available The increasing availability and popularity of computer systems has resulted in a demand for new, language- and platform-independent ways of data exchange. That demand has in turn led to a significant growth in the importance of systems based on Web services. Alongside the growing number of systems accessible via Web services came the need for specialized data repositories that could offer effective means of searching of available services. The development of mobile systems and wireless data transmission technologies has allowed the use of distributed devices and computer systems on a greater scale. The accelerating growth of distributed systems might be a good reason to consider the development of distributed Web service repositories with built-in mechanisms for data migration and synchronization.
Industrial complementarities between interim storage and reversible geological repository - 59237

International Nuclear Information System (INIS)

Hoorelbeke, Jean-Michel

2012-01-01

The French Act voted in 2006 made the choice of deep geological disposal as the reference option for the long term management of high level (HLW) and intermediate level long-lived waste. The CIGEO repository project aims at avoiding or limiting burden to future generations, which could not be achieved by the extension in time of interim storage. The reversibility as provided by the Act will maintain a liberty of choice for waste management on a duration which is comparable to new storage facility. Interim storage is required to accommodate waste as long as the repository is not available. The commissioning of the repository in 2025 will not suppress needs for interim storage. The paper describes the complementarities between existing and future interim storage facilities and the repository project: repository operational issues and planning, HLW thermal decay, support for the reversibility, etc. It shows opportunities to prepare a global optimization of waste management including the utilization at best of storage capacities and the planning of waste emplacement in the repository in such a way to facilitate operational conditions and to limit cost. Preliminary simulations of storage-disposal scenarios are presented. Thanks to an optimal use of the waste management system, provision can be made for a progressive increase of waste emplacement flow during the first operation phase of the repository. It is then possible to stabilize the industrial activity level of the repository site. An optimal utilization of interim storage can also limit the diversity of waste packages emplaced simultaneously, which facilitates the operation of the repository. 60 years minimum interim storage duration is generally required with respect to HLW thermal output. Extending this interim storage period may reduce the underground footprint of the repository. Regarding reversibility, the capability to manage waste packages potentially retrieved from the repository should be analyzed. The
DDC in DSpace: Integration of Multi-lingual Subject Access System in Institutional Digital Repositories

Directory of Open Access Journals (Sweden)

Bijan Kumar Roy

2017-12-01

Full Text Available The paper discusses the nature of Knowledge Organization Systems (KOSs and shows how these can support digital library users. It demonstrates processes related to integration of KOS like the Dewey Decimal Classification, 22nd edition (DDC22 in DSpace software (http://www.dspace.org/ for organizing and retrieving (browsing and searching scholarly objects. An attempt has been made to use the DDC22 available in Bengali language and highlights the required mechanisms for system-level integration. It may help repository administrator to build IDR (Institutional Digital Repository integrated with SKOS-enabled multilingual subject access systems for supporting subject descriptors based indexing (DC.Subject metadata element, structured navigation (browsing and efficient searching.
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
Environmental remediation of high-level nuclear waste in geological repository. Modified computer code creates ultimate benchmark in natural systems

International Nuclear Information System (INIS)

Peter, Geoffrey J.

2011-01-01

Isolation of high-level nuclear waste in permanent geological repositories has been a major concern for over 30 years due to the migration of dissolved radio nuclides reaching the water table (10,000-year compliance period) as water moves through the repository and the surrounding area. Repositories based on mathematical models allow for long-term geological phenomena and involve many approximations; however, experimental verification of long-term processes is impossible. Countries must determine if geological disposal is adequate for permanent storage. Many countries have extensively studied different aspects of safely confining the highly radioactive waste in an underground repository based on the unique geological composition at their selected repository location. This paper discusses two computer codes developed by various countries to study the coupled thermal, mechanical, and chemical process in these environments, and the migration of radionuclide. Further, this paper presents the results of a case study of the Magma-hydrothermal (MH) computer code, modified by the author, applied to nuclear waste repository analysis. The MH code verified by simulating natural systems thus, creating the ultimate benchmark. This approach based on processes similar to those expected near waste repositories currently occurring in natural systems. (author)
Systems engineering management plan for the Salt Repository Project

International Nuclear Information System (INIS)

Neff, J.O.

1986-08-01

This document presents the plan for using systems engineering in conducting and managing the technical work of the Salt Repository Project (SRP) of the US Department of Energy's Civilian Radioactive Waste Management Program. The need for preparing a Systems Engineering Management Plan (SEMP) is traced back to relevant DOE directives. These directives are interpreted as SRP requirements in the context of the Mined Geologic Disposal System. The strategy for conducting systems engineering on the SRP, including the role of the systems engineering process, is then described. The SEMP also designates who in the project organization will be responsible for carrying out the activities. Finally, the management tools that are used to implement the systems engineering process, including associated documentation on the SRP, are described
Learning object repositories as knowledge management systems

Directory of Open Access Journals (Sweden)

Demetrios G. Sampson

2013-06-01

Full Text Available Over the past years, a number of international initiatives that recognize the importance of sharing and reusing digital educational resources among educational communities through the use of Learning Object Repositories (LORs have emerged. Typically, these initiatives focus on collecting digital educational resources that are offered by their creators for open access and potential reuse. Nevertheless, most of the existing LORs are designed more as digital repositories, rather than as Knowledge Management Systems (KMS. By exploiting KMSs functionalities in LORs would bare the potential to support the organization and sharing of educational communities’ explicit knowledge (depicted in digital educational resources constructed by teachers and/or instructional designers and tacit knowledge (depicted in teachers’ and students’ experiences and interactions of using digital educational resources available in LORs. Within this context, in this paper we study the design and the implementation of fourteen operating LORs from the KMSs’ perspective, so as to identify additional functionalities that can support the management of educational communities’ explicit and tacit knowledge. Thus, we propose a list of essential LORs’ functionalities, which aim to facilitate the organization and sharing of educational communities’ knowledge. Finally, we present the added value of these functionalities by identifying their importance towards addressing the current demands of web-facilitated educational communities, as well as the knowledge management activities that they execute.
Preconceptual systems and equipment for plugging of man-made accesses to a repository in basalt

International Nuclear Information System (INIS)

Taylor, C.L.; O'Rourke, J.E.; Allirot, D.; O'Connor, K.

1980-09-01

This report presents results of a study leading to preconceptual designs for plugging boreholes, shafts, and tunnels to a nuclear waste repository in basalt. Beginning design criteria include a list of preferred plug materials and plugging machines that were selected to suit the environmental conditions, and depths, diameters, and orientations of the accesses to a nuclear waste repository in the Columbia River basalts located in eastern Washington State. The environmental conditions are described. The fiscal year 1979-1980 Task II work is presented in two parts: preliminary testing of materials for plugging of man-made accesses to a repository in basalt (described in a separate report); and preconceptual systems and equipment for plugging of man-made accesses to a repository in basalt (described in this report). To fulfill the scope of the Task II work, Woodward-Clyde Consultants (WCC) was requested to: provide preconceptual systems for plugging boreholes, tunnels, and shafts in basalt; describe preconceptual borehole plugging equipment for placing the selected materials in man-made accesses; utilize the quality assurance program, program plan and schedule, and work plans previously developed for Task II; and prepare a preliminary report
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
Nuclear waste repository research at the micro- to nanoscale

Science.gov (United States)

Schäfer, T.; Denecke, M. A.

2010-04-01

Micro- and nano-focused synchrotron radiation techniques to investigate determinant processes in contaminant transport in geological media are becoming especially an increasingly used tool in nuclear waste disposal research. There are a number of reasons for this but primarily they are driven by the need to characterize actinide speciation localized in components of heterogeneous natural systems. We summarize some of the recent research conducted by researchers of the Institute of Nuclear Waste Disposal (INE) at the Karlsruhe Institute of Technology using micro- and nano-focused X-ray beams for characterization of colloids and their interaction with minerals and of elemental and phase distributions in potential repository host rocks and actinide speciation in a repository natural analogues sample. Such investigations are prerequisite to ensuring reliable assessment of the long term radiological safety for proposed nuclear waste disposal sites.
International comparison of safety criteria applied to radwaste repositories. Safety aspects of the post-operational phase

International Nuclear Information System (INIS)

Baltes, B.

1994-01-01

There is a generally accepted system of framework safety conditions governing the construction, operation, and post-operational monitoring of radwaste repositories. Although the development of these framework conditions may vary from country to country, the resulting criteria are based on the commonly accepted system of priciples and purposes established for ultimate radioactive waste disposal. The experience accumulated by GRS in the course of the plan approval procedure for the Konrad mine site and the safety-relevant studies performed for the planned Morsleben repository clearly show demand for further development of the safety criteria. In Germany, it is especially the safety criteria and detailed requirements filling the framework safety conditions that need revision and in-depth definition, as well as comparison and harmonisation with internationally applied criteria. These activities will particularly consider the international convention on radioactive waste management currently in preparation under the auspieces of the IAEA. (orig.) [de
Repository Subsurface Preliminary Fire Hazard Analysis

International Nuclear Information System (INIS)

Logan, Richard C.

2001-01-01

This fire hazard analysis identifies preliminary design and operations features, fire, and explosion hazards, and provides a reasonable basis to establish the design requirements of fire protection systems during development and emplacement phases of the subsurface repository. This document follows the Technical Work Plan (TWP) (CRWMS M and O 2001c) which was prepared in accordance with AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities''; Attachment 4 of AP-ESH-008, ''Hazards Analysis System''; and AP-3.11Q, ''Technical Reports''. The objective of this report is to establish the requirements that provide for facility nuclear safety and a proper level of personnel safety and property protection from the effects of fire and the adverse effects of fire-extinguishing agents
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.)

Computer enhanced release scenario analysis for a nuclear waste repository

International Nuclear Information System (INIS)

Stottlemyre, J.A.; Petrie, G.M.; Mullen, M.F.

1979-01-01

An interactive (user-oriented) computer tool is being developed at PNL to assist in the analysis of release scenarios for long-term safety assessment of a continental geologic nuclear waste repository. Emphasis is on characterizing the various ways the geologic and hydrologic system surrounding a repository might vary over the 10 6 to 10 7 years subsequent to final closure of the cavern. The potential disruptive phenomena are categorized as natural geologic and man-caused and tend to be synergistic in nature. The computer tool is designed to permit simulation of the system response as a function of the ongoing disruptive phenomena and time. It is designed to be operated in a determinatic manner, i.e., user selection of the desired scenarios and associated rate, magnitude, and lag time data; or in a stochastic mode. The stochastic mode involves establishing distributions for individual phenomena occurrence probabilities, rates, magnitudes, and phase relationships. A Monte-Carlo technique is then employed to generate a multitude of disruptive event scenarios, scan for breaches of the repository isolation, and develop input to the release consequence analysis task. To date, only a simplified one-dimensional version of the code has been completed. Significant modification and development is required to expand its dimensionality and apply the tool to any specific site
Depth optimization for the Korean HLW repository System within a discontinuous and saturated granitic rock mass

International Nuclear Information System (INIS)

Kim, Jhin Wung; Bae, Dae Seok; Choi, Jong Won

2005-12-01

The present study is to evaluate the material properties of the compacted bentonite, backfill material, canister cast iron insert, and the rock mass for the Korean HLW repository system. These material properties are either measured, or taken from other countries, through the evaluation of the thermal, hydraulic, and mechanical interaction behavior of a repository. After the evaluation of the material properties, the most appropriate and economical depth as well as the layout of a single layer repository is to be recommended. Material properties used for the granitic rock mass, rock joints, PWR spent fuel, disposal canister, compacted bentonite, backfill material, and ground water are the data collected domestically, and foreign data are used for some of the data not available domestically. The repository model includes a saturated granitic rock mass with joints, PWR spent fuel in a disposal canister surrounded by compacted bentonite inside a deposition hole, and backfill material in the rest of the space within a repository cavern
Identification of structures, systems, and components important to safety at the potential repository at Yucca Mountain

International Nuclear Information System (INIS)

Hartman, D.J.; Miller, D.D.; Klamerus, L.J.

1991-10-01

This study recommends which structures, systems, and components of the potential repository at Yucca Mountain are important to safety. The assessment was completed in April 1990 and uses the reference repository configuration in the Site Characterization Plan Conceptual Design Report and follows the methodology required at that time by DOE Procedure AP6.10-Q. Failures of repository items during the preclosure period are evaluated to determine the potential offsite radiation doses and associated probabilities. Items are important to safety if, in the event they fail to perform their intended function, an accident could result which causes a dose commitment greater than 0.5 rem to the whole body or any organ of an individual in an unrestricted area. This study recommends that these repository items include the structures that house spent fuel and high-level waste, the associated filtered ventilation exhaust systems, certain waste- handling equipment, the waste containers, the waste treatment building structure, the underground waste transporters, and other items listed in this report. This work was completed April 1990. 27 refs., 7 figs., 9 tabs
Stability of underground excavations in a repository system

International Nuclear Information System (INIS)

Calash, A.Y.; Greer, J.C.; Andrea, S.J.; Chowdhury, A.H.; Nguyen, V.V.

1988-01-01

The DOE is investigating the feasibility of constructing a deep geologic repository at the Hanford Site, Washington, for the permanent disposal of nuclear waste. The underground openings associated with the repository design include shafts, tunnels, emplacement rooms and boreholes. The stability of these underground openings, the extent and characteristics of the disturbed zones due to excavation, and their effects on groundwater flow path and travel time have a primary influence on the performance assessment of the Hanford Site as a nuclear waste repository. This study is being done in accordance with the requirements of the NRC. Results of structural analyses of shafts and tunnels under in situ stresses and/or medium weight are presented in this paper. Four different analyses were carried out to analyze the shaft: a plane strain model, axisymmetric model, 3-D model of a single material medium, and 3-D model of a three material medium
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
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.
Uncertainty: a discriminator for above and below boiling repository design decisions

International Nuclear Information System (INIS)

Wilder, D G; Lin, W; Buscheck, T A; Wolery, T J; Francis, N D

2000-01-01

The US nuclear waste disposal program is evaluating the Yucca Mountain (YM) site for possible disposal of nuclear waste. Radioactive decay of the waste, particularly spent fuel, generates sufficient heat to significantly raise repository temperatures. Environmental conditions in the repository system evolve in response to this heat. The amount of temperature increase, and thus environmental changes, depends on repository design and operations. Because the evolving environment cannot be directly measured until after waste is emplaced, licensing decisions must be based upon model and analytical projections of the environmental conditions. These analyses have inherent uncertainties. There is concern that elevated temperatures increase uncertainty, because most chemical reaction rates increase with temperature and boiling introduces additional complexity of vapor phase reactions and transport. This concern was expressed by the NWTRB, particularly for above boiling temperatures. They state that ''the cooler the repository, the lower the uncertainty about heat-driven water migration and the better the performance of waste package materials. Above this temperature, technical uncertainties tend to be significantly higher than those associated with below-boiling conditions.'' (Cohon 1999). However, not all uncertainties are reduced by lower temperatures, indeed some may even be increased. This paper addresses impacts of temperatures on uncertainties
High level nuclear waste repository in salt: Sealing systems status and planning report: Draft report

International Nuclear Information System (INIS)

1985-09-01

This report documents the initial conceptual design studies for a repository sealing system for a high-level nuclear waste repository in salt. The first step in the initial design studies was to review the current design level, termed schematic designs. This review identified practicality of construction and development of a design methodology as two key issues for the conceptual design. These two issues were then investigated during the initial design studies for seal system materials, seal placement, backfill emplacement, and a testing and monitoring plan. The results of these studies have been used to develop a program plan for completion of the sealing system conceptual design. 60 refs., 26 figs., 18 tabs
Planning and Design Considerations for Geological Repository Programmes of Radioactive Waste

International Nuclear Information System (INIS)

2014-11-01

Disposal in a geological repository is the generally accepted solution for the long term management of high level and/or long lived radioactive wastes, in line with the general principles defined in the IAEA Safety Fundamentals. This publication presents practical information on the way a geological repository programme for radioactive waste could be defined and planned, with special attention to all aspects having an impact on the timing. Country specific examples for repository development phases are provided, based on actual experiences from Member States
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
The importance of the retrievability of nuclear waste for the implementation of safeguard regimes for geologic repositories

International Nuclear Information System (INIS)

Swahn, J.A.

1999-01-01

To find acceptance for the construction and siting of spent fuel repositories retrievability of the spent fuel is a desired feature. In order to minimize the levels of safeguards needed for the plutonium in spent fuel repositories the retrievability should be as low as possible. These contradictory goals have be balanced against each other during the operational phase, before closure and after closure of the repository. Arguments can be made for having the spent fuel in a highly-retrievable state during the operational phase, in a semi-retrievable state at the end of the operational phase but before closure and in a low-retrievable state after closure. The spent fuel in a mined geologic repository will never be able to be considered irretrievable and surveillance of the repository will be needed for an extended time after closure. The level of safeguards needed will depend on the local, regional and global societal conditions for several hundred thousand years into the future. (author)
Aspects of igneous activity significant to a repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Krier, D.J.; Perry, F.V.

2004-01-01

Location, timing, volume, and eruptive style of post-Miocene volcanoes have defined the volcanic hazard significant to a proposed high-level radioactive waste (HLW) and spent nuclear fuel (SNF) repository at Yucca Mountain, Nevada, as a low-probability, high-consequence event. Examination of eruptive centers in the region that may be analogueues to possible future volcanic activity at Yucca Mountain have aided in defining and evaluating the consequence scenarios for intrusion into and eruption above a repository. The probability of a future event intersecting a repository at Yucca Mountain has a mean value of 1.7 x 10 -8 per year. This probability comes from the Probabilistic Volcanic Hazard Assessment (PVHA) completed in 1996 and updated to reflect change in repository layout. Since that time, magnetic anomalies representing potential buried volcanic centers have been identified fiom magnetic surveys; however these potential buried centers only slightly increase the probability of an event intersecting the repository. The proposed repository will be located in its central portion of Yucca Mountain at approximately 300m depth. The process for assessing performance of a repository at Yucca Mountain has identified two scenarios for igneous activity that, although having a very low probability of occurrence, could have a significant consequence should an igneous event occur. Either a dike swarm intersecting repository drifts containing waste packages, or a volcanic eruption through the repository could result in release of radioactive material to the accessible environment. Ongoing investigations are assessing the mechanisms and significance of the consequence scenarios. Lathrop Wells Cone (∼80,000 yrs), a key analogue for estimating potential future volcanic activity, is the youngest surface expression of apparent waning basaltic volcanism in the region. Cone internal structure, lavas, and ash-fall tephra have been examined to estimate eruptive volume, eruption
Geographical information system (GIS) suitability analysis of radioactive waste repository site in Pahang, Malaysia

International Nuclear Information System (INIS)

Faizal Azrin Abd Razalim; Noraini Surip; Ahmad Hasnulhadi; Nazran Harun; Nurul Nadia Abd Malek; Roziah Che Musa

2010-01-01

The aim of this project is to identify a suitable site for radioactive waste repository in Pahang using remote sensing and geographical information system (GIS) technologies. There are ten parameters considered in the analysis, which divided into Selection Criteria and Exclusion Criteria. The Selection Criteria parameters consists of land use, rainfall, lineament, slope, groundwater potential and elevation while Exclusion Criteria parameters consist of urban, protected land and island. Furthermore, all parameters were integrated, given weight age and ranked for site selection evaluation in GIS environment. At the first place, about twelve sites have been identified as suitable sites for radioactive waste repository throughout the study area. These sites were further analysed by ground checking on the physical setting including geological, drainage, and population density in order to finalise three most suitable sites for radioactive waste repository. (author)
Development of geological disposal system; localization of element cost data and cost evaluation on the HLW repository

Energy Technology Data Exchange (ETDEWEB)

Lee, Byung Sik; Kim, Kil Jung; Yang, Young Jin; Kim, Sung Chun [KOPEC, Taejeon (Korea)

2002-03-01

To estimate Total Life Cycle Cost (TSLCC) for Korea HLW Repository through localization of element cost data, we review and re-organize each basic element cost data for reference repository system, localize various element cost and finally estimate TSLCC considering economic parameters. As results of the study, TSLCC is estimated as 17,167,689 million won, which includes costs for site preparation, surface facilities, underground facilities and management/integration. Since HLW repository Project is an early stage of pre-conceptual design at present, the information of design and project information are not enough to perform cost estimate and cost localization for the Project. However, project cost structure is re-organized based on the local condition and Total System Life Cycle Cost is estimated using the previous cost data gathered from construction experience of the local nuclear power plant. Project results can be used as basic reference data to assume total construction cost for the local HLW repository and should be revised to more reliable cost data with incorporating detail project design information into the cost estimate in a future. 20 refs. (Author)
Functions of an engineered barrier system for a nuclear waste repository in basalt

International Nuclear Information System (INIS)

Coons, W.E.; Moore, E.L.; Smith, M.J.; Kaser, J.D.

1980-01-01

Defined in this document are the functions of components selected for an engineered barrier system for a nuclear waste repository in basalt. The definitions provide a focal point for barrier material research and development by delineating the purpose and operative lifetime of each component of the engineered system. A five-component system (comprised of waste form, canister, buffer, overpack, and tailored backfill) is discussed in terms of effective operation throughout the course of repository history, recognizing that the emplacement environment changes with time. While components of the system are mutually supporting, redundancy is provided by subsystems of physical and chemical barriers which act in concert with the geology to provide a formidable barrier to transport of hazardous materials to the biosphere. The operating philosophy of the conceptual engineered barrier system is clarified by examples pertinent to storage in basalt, and a technical approach to barrier design and material selection is proposed. A method for system validation and qualification is also included which considers performance criteria proposed by external agencies in conjunction with site-specific models and risk assessment to define acceptable levels of system performance
Aspects on the gas generation and migration in repositories for high level waste in salt formations

International Nuclear Information System (INIS)

Ruebel, Andre; Buhmann, Dieter; Meleshyn, Artur; Moenig, Joerg; Spiessl, Sabine

2013-07-01

In a deep geological repository for high-level waste, gases may be produced during the post-closure phase by several processes. The generated gases can potentially affect safety relevant features and processes of the repository, like the barrier integrity, the transport of liquids and gases in the repository and the release of gaseous radionuclides from the repository into the biosphere. German long-term safety assessments for repositories for high-level waste in salt which were performed prior 2010 did not explicitly consider gas transport and the consequences from release of volatile radionuclides. Selected aspects of the generation and migration of gases in repositories for high-level waste in a salt formation are studied in this report from the viewpoint of the performance assessment. The knowledge on the availability of water in the repository, in particular the migration of salt rock internal fluids in the temperature field of the radioactive waste repository towards the emplacement drifts, was compiled and the amount of water was roughly estimated. Two other processes studied in this report are on the one hand the release of gaseous radionuclides from the repository and their potential impact in the biosphere and on the other hand the transport of gases along the drifts and shafts of the repository and their interaction with the fluid flow. The results presented show that there is some gas production expected to occur in the repository due to corrosion of container material from water disposed of with the backfill and inflowing from the host rock during the thermal phase. If not dedicated gas storage areas are foreseen in the repository concept, these gases might exceed the storage capacity for gases in the repository. Consequently, an outflow of gases from the repository could occur. If there are failed containers for spent fuel, radioactive gases might be released from the containers into the gas space of the backfill and subsequently transported together
An OAI repository centric peer-review model

CERN Multimedia

CERN. Geneva

2005-01-01

Pre-print repositories have seen a significant increase in use over the past fifteen years across multiple research domains. Researchers are beginning to develop applications capable of using these repositories to assist the scientific community above and beyond the pure dissemination of information. The contributions set forth by this paper emphasize a deconstructed publication model where in which the peer-review certification phase of a pre-print is mediated by an OAI-compliant peer-review service. This peer-review service uses a social-network algorithm for determining potential reviewers for a submitted manuscript and for weighting the influence of each participating reviewer’s evaluations. The paper also provides a set of peer-review specific metadata tags that can accompany a pre-prints existing metadata record. The combinations of these contributions provide a unique repository-centric peer-review model within the framework of the current OAI standards existing today.
Use of One-On Analysis to Evaluate Total System Performance of the Proposed Yucca Mountain Nuclear Waste Repository

International Nuclear Information System (INIS)

Saulnier, G.J. Jr.; Lee, K.P.; Mehta, S.; Sevougian, S.D.; Kalinich, D.; McNeish, J.A.

2002-01-01

The Yucca Mountain Site Characterization Project is currently evaluating the future performance of the proposed U.S. high-level nuclear waste repository. Using the Total System Performance Assessment (TSPA) model, a stylized analysis was conducted to evaluate the relative importance of natural and engineered barriers to movement of radionuclides from the proposed repository. These stylized ''one-on'' analyses consist of sequentially adding features, components, and processes, associated with the natural and engineered barriers, incorporated within the TSPA model and evaluating the effect of these elements on repository performance, as measured by the total mean annual dose to a reasonably maximally exposed individual. The analyses are ''stylized'' in the sense that they are performed to gain insight only. They are not meant to represent a real physical system in most cases, and in some cases allow the TSPA model to simulate results using parameter ranges outside the normal bounds of the TSPA model. In particular, the analyses provide insight into the relative contributions of repository features and processes in a way that is not possible using the full TSPA performance-assessment model. For example, in the nominal scenario of the TSPA model, the contribution of the natural system is masked by the contribution of the engineered system
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
Closure development for high-level nuclear waste containers for the tuff repository; Phase 1, Final report

Energy Technology Data Exchange (ETDEWEB)

Robitz, E.S. Jr.; McAninch, M.D. Jr.; Edmonds, D.P. [Babcock and Wilcox Co., Lynchburg, VA (USA). Nuclear Power Div.]|[Babcock and Wilcox Co., Alliance, OH (USA). Research and Development Div.

1990-09-01

This report summarizes Phase 1 activities for closure development of the high-level nuclear waste package task for the tuff repository. Work was conducted under U.S. Department of Energy (DOE) Contract 9172105, administered through the Lawrence Livermore National Laboratory (LLNL), as part of the Yucca Mountain Project (YMP), funded through the DOE Office of Civilian Radioactive Waste Management (OCRWM). The goal of this phase was to select five closure processes for further evaluation in later phases of the program. A decision tree methodology was utilized to perform an objective evaluation of 15 potential closure processes. Information was gathered via a literature survey, industrial contacts, and discussions with project team members, other experts in the field, and the LLNL waste package task staff. The five processes selected were friction welding, electron beam welding, laser beam welding, gas tungsten arc welding, and plasma arc welding. These are felt to represent the best combination of weldment material properties and process performance in a remote, radioactive environment. Conceptual designs have been generated for these processes to illustrate how they would be implemented in practice. Homopolar resistance welding was included in the Phase 1 analysis, and developments in this process will be monitored via literature in Phases 2 and 3. Work was conducted in accordance with the YMP Quality Assurance Program. 223 refs., 20 figs., 9 tabs.

Identifying Tensions in the Use of Open Licenses in OER Repositories

Science.gov (United States)

Amiel, Tel; Soares, Tiago Chagas

2016-01-01

We present an analysis of 50 repositories for educational content conducted through an "audit system" that helped us classify these repositories, their software systems, promoters, and how they communicated their licensing practices. We randomly accessed five resources from each repository to investigate the alignment of licensing…
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
Repository waste-handling operations, 1998

International Nuclear Information System (INIS)

Cottam, A.E.; Connell, L.

1986-04-01

The Civilian Radioactive Waste Management Program Mission Plan and the Generic Requirements for a Mined Geologic Disposal System state that beginning in 1998, commercial spent fuel not exceeding 70,000 metric tons of heavy metal, or a quantity of solidified high-level radioactive waste resulting from the reprocessing of such a quantity of spent fuel, will be shipped to a deep geologic repository for permanent storage. The development of a waste-handling system that can process 3000 metric tons of heavy metal annually will require the adoption of a fully automated approach. The safety and minimum exposure of personnel will be the prime goals of the repository waste handling system. A man-out-of-the-loop approach will be used in all operations including the receipt of spent fuel in shipping casks, the inspection and unloading of the spent fuel into automated hot-cell facilities, the disassembly of spent fuel assemblies, the consolidation of fuel rods, and the packaging of fuel rods into heavy-walled site-specific containers. These containers are designed to contain the radionuclides for up to 1000 years. The ability of a repository to handle more than 6000 pressurized water reactor spent-fuel rods per day on a production basis for approximately a 23-year period will require that a systems approach be adopted that combines space-age technology, robotics, and sophisticated automated computerized equipment. New advanced inspection techniques, maintenance by robots, and safety will be key factors in the design, construction, and licensing of a repository waste-handling facility for 1998
Multiscale Model Simulations of Temperature and Relative Humidity for the License Application of the Proposed Yucca Mountain Repository

Science.gov (United States)

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

2003-12-01

For the proposed Yucca Mountain geologic repository for high-level nuclear waste, the planned method of disposal involves the emplacement of cylindrical packages containing the waste inside horizontal tunnels, called emplacement drifts, bored several hundred meters below the ground surface. The emplacement drifts reside in highly fractured, partially saturated volcanic tuff. An important phenomenological consideration for the licensing of the proposed repository at Yucca Mountain is the generation of decay heat by the emplaced waste and the consequences of this decay heat. Changes in temperature will affect the hydrologic and chemical environment at Yucca Mountain. A thermohydrologic-modeling tool is necessary to support the performance assessment of the Engineered Barrier System (EBS) of the proposed repository. This modeling tool must simultaneously account for processes occurring at a scale of a few tens of centimeters around individual waste packages, for processes occurring around the emplacement drifts themselves, and for processes occurring at the multi-kilometer scale of the mountain. Additionally, many other features must be considered including non-isothermal, multiphase-flow in fractured porous rock of variable liquid-phase saturation and thermal radiation and convection in open cavities. The Multiscale Thermohydrologic Model (MSTHM) calculates the following thermohydrologic (TH) variables: temperature, relative humidity, liquid-phase saturation, evaporation rate, air-mass fraction, gas-phase pressure, capillary pressure, and liquid- and gas-phase fluxes. The TH variables are determined as a function of position along each of the emplacement drifts in the repository and as a function of waste-package (WP) type. These variables are determined at various generic locations within the emplacement drifts, including the waste package and drip-shield surfaces and in the invert; they are also determined at various generic locations in the adjoining host rock
Framework for evaluating the utility of incentive systems for radioactive waste repository siting

International Nuclear Information System (INIS)

Carnes, S.A.; Soderstrom, E.J.; Sorensen, J.; Peelle, E.; Reed, J.H.; Bjornstad, D.J.; Copenhaver, E.D.

1982-01-01

The importance of social and institutional issues in siting radioactive waste repositories has been recognized in recent years. Within this set of issues, the siting of repositories over the objections of members of potential host communities is viewed as especially problematic. Incentives to potential host communities have been suggested as a means of increasing local support for and offsetting local opposition to such facilities. Incentives are classified according to their function as mitigation, compensation or reward. Our analysis of results of a 1980 survey (conducted by John Kelly, Complex Systems Group, University of New Hampshire) of 420 rural Wisconsin residents indicates that incentives may achieve the purpose of increasing support for and decreasing opposition to accepting a repository. Criteria for evaluating the utility of incentives are identified. They respond to four basic questions: (1) What is absolutely necessary. (2) Will the incentive work. (3) Can the incentive be understood. and (4) What are the consequences of implementing the incentive. It is suggested that meaningful evaluations of incentives can only be performed by members of potential host communities
Double Diffusive Natural Convection in a Nuclear Waste Repository

International Nuclear Information System (INIS)

Y. Hao; J. Nitao; T.A. Buscheck; Y. Sun

2006-01-01

In this study, we conduct a two-dimensional numerical analysis of double diffusive natural convection in an emplacement drift for a nuclear waste repository. In-drift heat and moisture transport is driven by combined thermal- and compositional-induced buoyancy forces. Numerical results demonstrate buoyancy-driven convective flow patterns and configurations during both repository heat-up and cool-down phases. It is also shown that boundary conditions, particularly on the drip-shield surface, have strong impacts on the in-drift convective flow and transport
Thermodynamic Properties of Magnesium Chloride Hydroxide Hydrate (Mg3Cl(OH)5:4H2O, Phase 5), and Its importance to Nuclear Waste Isolation in Geological Repositories in Salt Formations

Science.gov (United States)

Xiong, Y.; Deng, H.; Nemer, M. B.; Johnsen, S.

2009-12-01

-1, respectively. Phase 5, and its similar phase, phase 3 (Mg2Cl(OH)3:4H2O), could have a significant role in influencing the geochemical conditions in geological repositories for nuclear waste in salt formations where MgO or brucite is employed as engineered barriers, when Na-Mg-Cl dominated brines react with MgO or brucite. Based on our solubility constant for phase 5 in combination with the literature value for phase 3, we predict that the composition for the invariant point of phase 5 and phase 3 would be mMg = 1.70 and pmH = 8.93 in the Mg-Cl binary system. The recent WIPP Compliance Recertification Application PA Baseline Calculations indicate that phase 5 instead of phase 3 is indeed a stable phase when GWB equilibrates with actinide-source-term phases, brucite, magnesium carbonates, halite and anhydrite. 1. This research is funded by WIPP programs administered by the U.S. Department of Energy. 2. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.
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.
Ventilation planning for a prospective nuclear waste repository

International Nuclear Information System (INIS)

Wallace, K.G. Jr.

1987-01-01

In 1982, the US Congress passed the Nuclear Waste Policy Act to provide for the development of underground repositories for spent nuclear fuel. This development will be managed by the United States Department of Energy. In 1986, the President selected three areas for site characterization to determine their suitability for the development of an underground repository; those sites were: (1) A site in volcanic tuff located at Yucca Mountain in Nevada, (2) a site in bedded salt located in Deaf Smith County in Texas, and (3) a site in basalt located in Hanford, Washington. At present conceptual repository designs are being developed for each site. A key element of a repository design is the underground ventilation system required to support construction, nuclear waste emplacement, and potential waste retrieval. This paper describes the preliminary ventilation systems designed for the repository in tuff. The concept provides separate ventilation systems for the construction and waste emplacement activities. The paper further describes the means by which acceptable environmental conditions will be re-established to allow re-entry into previously closed rooms for the purpose of inspection, maintenance or retrieval
Inverse modeling for the determination of hydrogeological parameters of a two-phase system

International Nuclear Information System (INIS)

Finsterle, S.

1993-02-01

Investigations related to the disposal of radioactive wastes in Switzerland consider formations containing natural gas as potential rocks for a repository. Moreover, gas generation in the repository itself may lead to an unsaturated zone of significant extent and impact on the system's performance. The site characterization procedure requires the estimation of hydraulic properties being used as input parameters for a two-phase two-component numerical simulator. In this study, estimates of gas-related formation parameters are obtained by inverse modeling. Based on discrete observations of the system's state, model parameters can be estimated within the framework of a given conceptual model by means of optimization techniques. This study presents the theoretical background that related field data to the model parameters. A parameter estimation procedure is proposed and implemented in a computer code for automatic model calibration. This tool allows identification of key parameters affecting flow of water and gas in porous media. The inverse modeling approach is verified using data from a synthetic laboratory experiment. In addition, the Gas test performed at the Grimsel Test Site is analyzed in order to demonstrate the applicability of the proposed procedure when used with data from a real geologic environment. Estimation of hydrogeologic parameters by automatic model calibration improves the understanding of the two-phase flow processes and therefore increases the reliability of the subsequent simulation runs. (author) figs., tabs., refs
Inverse modeling for the determination of hydrogeological parameters of a two-phase system

International Nuclear Information System (INIS)

Finsterle, S.

1993-01-01

Investigations related to the disposal of radioactive wastes in Switzerland are dealing with formations containing natural gas as potential host rock for a repository. Moreover, gas generation in the repository itself may lead to an unsaturated zone of significant extent and impact on the system's performance. The site characterization procedure requires the estimation of hydraulic properties being used as input parameters for a two-phase two-component numerical simulator. In this study, estimates of gas related formation parameters are obtained by inverse modeling. Based on discrete observations of the system's state, model parameters can be estimated within the framework of a given conceptual model by means of optimization techniques. This study presents the theoretical background that relates field data to the model parameters. A parameter estimation procedure is proposed and implemented in a computer code for automatic model calibration. This tool allows to identify key parameters affecting flow of water and gas in porous media. The inverse modeling approach is verified using data from a synthetic laboratory experiment. In addition, the Gastest performed at the Grimsel Test Site is analyzed in order to demonstrate the applicability of the proposed procedure when used with data from a real geologic environment. Estimation of hydrogeologic parameters by automatic model calibration improves the understanding of the two-phase flow processes and therefore increases the reliability of the subsequent simulation runs. (author) figs., tabs., 100 refs
Geochemical performance of earthen and cementitious sealing materials for radioactive waste repositories

International Nuclear Information System (INIS)

Melchoir, D.; Glazier, R.; Marton, R.

1988-01-01

Earthen and cementitious materials are proposed as part of the sealing system for radioactive waste repositories. Compacted clay-bearing earthen materials could be used in sealing shafts and shaft entryways; and in the waste emplacement boundary areas in some repository designs. Earthen material mixtures are being considered because they can be engineered and emplaced to achieve low permeabilities, appropriate swelling characteristics, and adequate strength with little tendency to degrade during changing environmental conditions. The proposed earthen sealing materials include sodium and calcium mont-morillonites, illites, and mixtures with graded aggregates of sand. To assess the relative advantages and disadvantages of various pure and mixed materials, important geochemical processes (e.g., ion-exchange, phase transformation, dissolution, and precipitation of secondary minerals) need to be evaluated. These processes could impact seal integrity by changing permeability and/or mineral swell potential. Hydrous calcium-silicate-based cementitious materials such as grouts or concrete might also be used in some proposed sealing systems
The Geodetic Seamless Archive Centers Service Layer: A System Architecture for Federating Geodesy Data Repositories

Science.gov (United States)

McWhirter, J.; Boler, F. M.; Bock, Y.; Jamason, P.; Squibb, M. B.; Noll, C. E.; Blewitt, G.; Kreemer, C. W.

2010-12-01

Three geodesy Archive Centers, Scripps Orbit and Permanent Array Center (SOPAC), NASA's Crustal Dynamics Data Information System (CDDIS) and UNAVCO are engaged in a joint effort to define and develop a common Web Service Application Programming Interface (API) for accessing geodetic data holdings. This effort is funded by the NASA ROSES ACCESS Program to modernize the original GPS Seamless Archive Centers (GSAC) technology which was developed in the 1990s. A new web service interface, the GSAC-WS, is being developed to provide uniform and expanded mechanisms through which users can access our data repositories. In total, our respective archives hold tens of millions of files and contain a rich collection of site/station metadata. Though we serve similar user communities, we currently provide a range of different access methods, query services and metadata formats. This leads to a lack of consistency in the userís experience and a duplication of engineering efforts. The GSAC-WS API and its reference implementation in an underlying Java-based GSAC Service Layer (GSL) supports metadata and data queries into site/station oriented data archives. The general nature of this API makes it applicable to a broad range of data systems. The overall goals of this project include providing consistent and rich query interfaces for end users and client programs, the development of enabling technology to facilitate third party repositories in developing these web service capabilities and to enable the ability to perform data queries across a collection of federated GSAC-WS enabled repositories. A fundamental challenge faced in this project is to provide a common suite of query services across a heterogeneous collection of data yet enabling each repository to expose their specific metadata holdings. To address this challenge we are developing a "capabilities" based service where a repository can describe its specific query and metadata capabilities. Furthermore, the architecture of
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.)
Hydrogeological modelling for assessment of radionuclide release scenarios for the repository system 2012

Energy Technology Data Exchange (ETDEWEB)

Hartley, L.; Hoek, J.; Swan, D.; Appleyard, P.; Baxter, S.; Roberts, D.; Simpson, T. [AMEC (United Kingdom)

2013-07-15

Posiva Oy is responsible for implementing the programme for geological disposal of spent nuclear fuel produced by its owners Teollisuuden Voima Oyj (TVO) and Fortum Power and Heat Oy in Finland. Olkiluoto in Eurajoki has been selected as the primary site for the repository, subject to further detailed investigation which is currently focused on the construction of an underground rock characterisation and research facility (the ONKALO). An essential part of the assessment of long-term safety of a repository is the analysis of groundwater flow since it is the only means of transport of radionuclides to the biosphere (besides human intrusion). The analysis of long-term safety for a KBS-3 concept requires as input a description of details of the groundwater flow around and through components of the engineered barrier system as well as details of the groundwater pathway to the biosphere during the current temperate climate period, as well as indications of behaviour under future climate periods such as glacial conditions. This report describes the groundwater flow modelling study performed to provide some of the necessary inputs required by Safety Assessment (i.e. radionuclide transport analysis). Underlying this study is the understanding of the site developed during the site investigations as summarised in the site descriptive model (SDM), and in particular the description of Olkiluoto Hydrogeological DFN model (Hydro-DFN). The main focus of this study is the temperate climate period, i.e. the evolution over the next 10,000 years, but the hydrogeological situation under various glacial climate conditions is also evaluated. Primary outputs of the study are repository performance measures relating to: the distributions of groundwater flow around the deposition holes; deposition tunnels and through the EDZ; flow-related transport resistance along groundwater pathways from the repository to the surface; and their the exit locations. Other analyses consider the
Hydrogeological modelling for assessment of radionuclide release scenarios for the repository system 2012

International Nuclear Information System (INIS)

Hartley, L.; Hoek, J.; Swan, D.; Appleyard, P.; Baxter, S.; Roberts, D.; Simpson, T.

2013-07-01

Posiva Oy is responsible for implementing the programme for geological disposal of spent nuclear fuel produced by its owners Teollisuuden Voima Oyj (TVO) and Fortum Power and Heat Oy in Finland. Olkiluoto in Eurajoki has been selected as the primary site for the repository, subject to further detailed investigation which is currently focused on the construction of an underground rock characterisation and research facility (the ONKALO). An essential part of the assessment of long-term safety of a repository is the analysis of groundwater flow since it is the only means of transport of radionuclides to the biosphere (besides human intrusion). The analysis of long-term safety for a KBS-3 concept requires as input a description of details of the groundwater flow around and through components of the engineered barrier system as well as details of the groundwater pathway to the biosphere during the current temperate climate period, as well as indications of behaviour under future climate periods such as glacial conditions. This report describes the groundwater flow modelling study performed to provide some of the necessary inputs required by Safety Assessment (i.e. radionuclide transport analysis). Underlying this study is the understanding of the site developed during the site investigations as summarised in the site descriptive model (SDM), and in particular the description of Olkiluoto Hydrogeological DFN model (Hydro-DFN). The main focus of this study is the temperate climate period, i.e. the evolution over the next 10,000 years, but the hydrogeological situation under various glacial climate conditions is also evaluated. Primary outputs of the study are repository performance measures relating to: the distributions of groundwater flow around the deposition holes; deposition tunnels and through the EDZ; flow-related transport resistance along groundwater pathways from the repository to the surface; and their the exit locations. Other analyses consider the
Reference design description for a geologic repository: Revision 01

International Nuclear Information System (INIS)

1997-09-01

This document describes the current design expectations for a potential geologic repository that could be located at Yucca Mountain in Nevada. This Reference Design Description (RDD) looks at the surface and subsurface repository and disposal container design. Additionally, it reviews the expected long-term performance of the potential repository. In accordance with current legislation, the reference design for the potential repository does not include an interim storage option. The reference design presented allows the disposal of highly radioactive material received from government-owned spent fuel custodian sites; produces high-level waste sites, and commercial spent fuel sites. All design elements meet current federal, state, and local regulations governing the disposal of high-level radioactive waste and protection of the public and the environment. Due to the complex nature of developing a repository, the design will be created in three phases to support Viability Assessment, License Application, and construction. This document presents the current reference design. It will be updated periodically as the design progresses. Some of the details presented here may change significantly as more cost-effective solutions, technical advancements, or changes to requirements are identified
Monitoring a repository for high-level radioactive waste in Germany. Possibilities and limits

International Nuclear Information System (INIS)

Jobmann, M.; Haverkamp, B.; Eilers, G.

2011-01-01

Pursuant to the new BMU safety requirements of September 2010 imposed upon the final storage of radioactive waste generating heat, the operator of a repository in Germany must establish a monitoring program which furnishes relevant measured information during the operations phase and for a defined period of time after closure of the repository. Within the framework of a feasibility study, an assessment basis was established to show in what format information about the status of a closed repository mine could be obtained technically without impairing the safety of barriers, for instance, by cable ducts. As a conceptual design basis, processes and measured quantities relevant to monitoring were attributed to the components of the current safety demonstration concept. For one model variant, monitoring possibilities of these processes were shown on the basis of monitoring modules. Some first experiments are being carried out in European underground laboratories about the use of wireless transmission systems in the repository area. On the basis of those activities, experiments could also be designed in the German exploratory mine of Gorleben in order to examine to what extent information obtained by monitoring could be transmitted in a wireless mode in rock salt formations. As far as the autonomous supply of electricity to measurement systems is concerned, which must be guaranteed on a long-term basis, there is now a possibility of using thermoelectric isotope generators or betavoltaic batteries. (orig.)
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
Probabilistic safety assessment for a generic deep geological repository for high-level waste and long-lived intermediate-level waste in clay

International Nuclear Information System (INIS)

Resele, G.; Holocher, J.; Mayer, G.; Hubschwerlen, N.; Niemeyer, M.; Beushausen, M.; Wollrath, J.

2010-01-01

probabilistic safety assessment, including the probabilities of the scenarios. - Evaluation of the significance of the results. Probabilistic calculations of the radionuclide release from the wastes and the transport through the host rock formation and overlying rock are the basis for the derivation of indicator values that weight the resulting radiologic consequences of the radionuclide release in the biosphere. These indicator values will be used to perform the comparison of the safety assessments of the repositories at the clay site and at the salt site. For the clay site, using the Monte Carlo simulation software GoldSim as platform for the system-level probabilistic simulations, the radionuclide release and transport is modelled in two steps: First, the 2-phase flow considering gas generation in the repository due to anaerobic steel corrosion is calculated using TOUGH2-MP. Besides the flow, the propagation of an ideal tracer that is released from the waste forms is simulated. In a second step, the resulting water flow out of the emplacement caverns is used as input in corresponding radionuclide transport calculations with the numerical code VPAC. VPAC simulates groundwater flow and radionuclide release and transport in fully saturated heterogeneous media in 3D, considering radioactive decay and ingrowth for the total set of safety-relevant radionuclides, solubility limitations, time-dependent hydraulic conductivities, time-dependent diffusion and time-dependent sorption. Besides the gas-induced water flow from the repository, the distribution of the tracer as calculated with TOUGH2-MP is used as input to the VPAC calculations. Due to the large and complex architecture of the repository, a detailed 3D modeling of the radionuclide transport in the repository system and the entire host rock and overlying rock would require a tremendous computational effort. Therefore, only the transport along the dominating pathway is simulated using VPAC. This dominating pathway is

Radionuclides in hydrothermal systems as indicators of repository conditions

International Nuclear Information System (INIS)

Wollenberg, H.A.; Flexser, S.; Smith, A.R.

1990-11-01

Hydrothermal systems in tuffaceous and older sedimentary rocks contain evidence of the interaction of radionuclides in fluids with rock matrix minerals and with materials lining fractures, in settings somewhat analogous to the candidate repository site at Yucca Mountain, NV. Earlier studies encompassed the occurrences of U and Th in a ''fossil'' hydrothermal system in tuffaceous rock of the San Juan Mountains volcanic field, CO. More recent and ongoing studies examine active hydrothermal systems in calderas at Long Valley, CA and Valles, NM. At the Nevada Test Site, occurrences of U and Th in fractured and unfractured rhyolitic tuff that was heated to simulate the introduction of radioactive waste are also under investigation. Observations to date suggest that U is mobile in hydrothermal systems, but that localized reducing environments provided by Fe-rich minerals and/or carbonaceous material concentrate U and thus attenuate its migration. 11 refs., 6 figs., 1 tab
Final Systems Development Report for the Clark County Socioeconomic Impact Assessment of the Proposed High-Level Nuclear Waste Repository at Yucca Mountain, NV

Energy Technology Data Exchange (ETDEWEB)

NONE

1992-06-18

The Systems Development Report represents the third major step in the Clark County Socioeconomic Impact Assessment of the Proposed High-Level Nuclear Waste Repository at Yucca Mound Nevada. The first of these steps was to forge a Research Design that would serve as a guide for the overall research process. The second step was the construction of the Base Case, the purpose of which was to describe existing conditions in Clark County in the specified analytic areas of Economic-Demographic/Fiscal, Emergency Planning and Management, Transportation and Sociocultural analysis. The base case description will serve as a basis for assessing changes in these topic areas that might result from the Yucca Mountain project. These changes will be assessed by analyzing conditions with and without repository development in the county. Prior to performing such assessments, however, the snapshot type of data found in the base case must be operationalized or systematized to allow for more dynamic data utilization. In other words, a data system that can be used to analyze the consequences of the introduction of different variables (or variable values) in the Clark County context must be constructed. Such a system must be capable of being updated through subsequent data collection and monitoring efforts to both provide a rolling base case and supply information necessary to construct trend analyses. For example, during the Impact Assessment phase of the study process, the without repository analysis is accomplished by analyzing growth for the county given existing conditions and likely trends. These data are then compared to the with Yucca Mountain project conditions anticipated for the county. Similarly, once the emergency planning management and response needs associated with the repository are described, these needs will be juxtaposed against existing (and various future) capacity(ies) in order to determine the nature and magnitude of impacts in this analytic area. Analogous tasks
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
Total System Performance Assessment, 1993: An evaluation of the potential Yucca Mountain repository

International Nuclear Information System (INIS)

Andrews, R.W.; Dale, T.F.; McNeish, J.A.

1994-03-01

Total System Performance Assessments are an important component in the evaluation of the suitability of Yucca Mountain, Nevada as a potential site for a mined geologic repository for the permanent disposal of high-level radioactive wastes in the United States. The Total System Performance Assessments are conducted iteratively during site characterization to identify issues which should be addressed by the characterization and design activities as well as providing input to regulatory/licensing and programmatic decisions. During fiscal years 1991 and 1992, the first iteration of Total System Performance Assessment (hereafter referred to as TSPA 1991) was completed by Sandia National Laboratories and Pacific Northwest Laboratory. Beginning in fiscal year 1993, the Civilian Radioactive Waste Management System Management and Operating Contractor was assigned the responsibility to plan, coordinate, and contribute to the second iteration of Total System Performance Assessment (hereafter referred to as TSPA 1993). This document presents the objectives, approach, assumptions, input, results, conclusions, and recommendations associated with the Management and Operating Contractor contribution to TSPA 1993. The new information incorporated in TSPA 1993 includes (1) revised estimates of radionuclide solubilities (and their thermal and geochemical dependency), (2) thermal and geochemical dependency of spent fuel waste alteration and glass dissolution rates, (3) new distribution coefficient (k d ) estimates, (4) revised estimates of gas-phase velocities and travel times, and (5) revised hydrologic modeling of the saturated zone which provides updated estimates of the advective flux through the saturated zone
Total System Performance Assessment, 1993: An evaluation of the potential Yucca Mountain repository

Energy Technology Data Exchange (ETDEWEB)

Andrews, R.W.; Dale, T.F.; McNeish, J.A.

1994-03-01

Total System Performance Assessments are an important component in the evaluation of the suitability of Yucca Mountain, Nevada as a potential site for a mined geologic repository for the permanent disposal of high-level radioactive wastes in the United States. The Total System Performance Assessments are conducted iteratively during site characterization to identify issues which should be addressed by the characterization and design activities as well as providing input to regulatory/licensing and programmatic decisions. During fiscal years 1991 and 1992, the first iteration of Total System Performance Assessment (hereafter referred to as TSPA 1991) was completed by Sandia National Laboratories and Pacific Northwest Laboratory. Beginning in fiscal year 1993, the Civilian Radioactive Waste Management System Management and Operating Contractor was assigned the responsibility to plan, coordinate, and contribute to the second iteration of Total System Performance Assessment (hereafter referred to as TSPA 1993). This document presents the objectives, approach, assumptions, input, results, conclusions, and recommendations associated with the Management and Operating Contractor contribution to TSPA 1993. The new information incorporated in TSPA 1993 includes (1) revised estimates of radionuclide solubilities (and their thermal and geochemical dependency), (2) thermal and geochemical dependency of spent fuel waste alteration and glass dissolution rates, (3) new distribution coefficient (k{sub d}) estimates, (4) revised estimates of gas-phase velocities and travel times, and (5) revised hydrologic modeling of the saturated zone which provides updated estimates of the advective flux through the saturated zone.
Development of an administrative record system and information repository system to support environmental cleanup at the Hanford Site in Richland, Washington

International Nuclear Information System (INIS)

Sprouse, B.S.

1991-09-01

The purpose of this paper is to describe the development of an administrative record (AR) file system for the Hanford Site in Richland, Washington. This paper will focus on the background of the AR system and its implementation at the Hanford Site; the types of documents to be included in an AR file; the management system used to develop and implement the AR system; the unique characteristics of the AR system and the role of the information repositories. The objective of this session is to present the methodology used in developing an AR and information repository system so that common hurdles from various sites can be addressed and resolved similarly. Therefore unnecessary effort does not have to be put forth to resolve the same issues over and over again. The concepts described can be applied to all federal facility sites with a minimum amount of modification and revision. 9 refs
Staged Repository Development Programmes

International Nuclear Information System (INIS)

Isaacs, T

2003-01-01

Programs to manage and ultimately dispose of high-level radioactive wastes are unique from scientific and technological as well as socio-political aspects. From a scientific and technological perspective, high-level radioactive wastes remain potentially hazardous for geological time periods-many millennia-and scientific and technological programs must be put in place that result in a system that provides high confidence that the wastes will be isolated from the accessible environment for these many thousands of years. Of course, ''proof'' in the classical sense is not possible at the outset, since the performance of the system can only be known with assurance, if ever, after the waste has been emplaced for those geological time periods. Adding to this challenge, many uncertainties exist in both the natural and engineered systems that are intended to isolate the wastes, and some of the uncertainties will remain regardless of the time and expense in attempting to characterize the system and assess its performance. What was perhaps underappreciated in the early days of waste management and repository program development were the unique and intense reactions that the institutional, political, and public bodies would have to repository program development, particularly in programs attempting to identify and then select sites for characterization, design, licensing, and ultimate development. Reactions in most nations were strong, focused, unrelenting, and often successful in hindering, derailing, and even stopping national repository programs. The reasons for such reactions and the measures to successfully respond to them are still evolving and continue to be the focus of many national program and political leaders. Adaptive Staging suggests an approach to repository program development that reflects the unique challenges associated with the disposal of high-level radioactive waste. The step-wise, incremental, learn-as-you-go approach is intended to maximize the
An assessment of gas impact on geological repository. Methodology and material property of gas migration analysis in engineered barrier system

International Nuclear Information System (INIS)

Yamamoto, Mikihiko; Mihara, Morihiro; Ooi, Takao

2004-01-01

Gas production in a geological repository has potential hazard, as overpressurisation and enhanced release of radionuclides. Amongst data needed for assessment of gas impact, gas migration properties of engineered barriers, focused on clayey and cementitious material, was evaluated in this report. Gas injection experiments of saturated bentonite sand mixture, mortar and cement paste were carried out. In the experiments, gas entry phenomenon and gas outflow rate were observed for these materials. Based on the experimental results, two-phase flow parameters were evaluated quantitatively. A conventional continuum two-phase flow model, which is only practically used multidimensional multi-phase flow model, was applied to fit the experimental results. The simulation results have been in good agreement with the gas entry time and the outflow flux of gas and water observed in the experiments. It was confirmed that application of the continuum two-phase flow model to gas migration in cementitious materials provides sufficient degree of accuracy for assessment of repository performance. But, for sand bentonite mixture, further extension of basic two-phase flow model is needed especially for effect of stress field. Furthermore, gas migration property of other barrier materials, including rocks, but long-term gas injection test, clarification of influence of chemicals environment and large-scale gas injection test is needed for multi-barrier assessment tool development and their verification. (author)
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.
Monte Carlo simulations for generic granite repository studies

Energy Technology Data Exchange (ETDEWEB)

Chu, Shaoping [Los Alamos National Laboratory; Lee, Joon H [SNL; Wang, Yifeng [SNL

2010-12-08

In a collaborative study between Los Alamos National Laboratory (LANL) and Sandia National Laboratories (SNL) for the DOE-NE Office of Fuel Cycle Technologies Used Fuel Disposition (UFD) Campaign project, we have conducted preliminary system-level analyses to support the development of a long-term strategy for geologic disposal of high-level radioactive waste. A general modeling framework consisting of a near- and a far-field submodel for a granite GDSE was developed. A representative far-field transport model for a generic granite repository was merged with an integrated systems (GoldSim) near-field model. Integrated Monte Carlo model runs with the combined near- and farfield transport models were performed, and the parameter sensitivities were evaluated for the combined system. In addition, a sub-set of radionuclides that are potentially important to repository performance were identified and evaluated for a series of model runs. The analyses were conducted with different waste inventory scenarios. Analyses were also conducted for different repository radionuelide release scenarios. While the results to date are for a generic granite repository, the work establishes the method to be used in the future to provide guidance on the development of strategy for long-term disposal of high-level radioactive waste in a granite repository.
Report of the Task Force on the MRS/repository interface

International Nuclear Information System (INIS)

1986-02-01

In April 1985, the DOE established an MRS/repository interface task force to analyze the cost and schedule impacts of implementing an integrated waste-management system on the repository and the MRS facility. The intended end products of the study were preliminary conceptual designs of repository and MRS facilities, cost and schedule estimates, and other analyses that would advance the definition of the role and function of the MRS facility, support the preparation of the MRS proposal to Congress, and serve as a source of baseline data for further studies of the integrated waste-management system. From the general overall objectives, specific equations were developed to guide the task-force effort, e.g., What would the surface facilities at the repository look like and cost with an MRS facility in the system. In order to address these questions, five scenarios were defined and analyzed. (A number of other scenarios and associated issues were also explored to a lesser extent.) These five scenarios are as follows. Scenario 1: reference case (no MRS facility). Scenario 2: MRS facility with overpacking of both spent fuel and defense high-level waste. Scenario 3: MRS facility with overpacking of spent fuel only (defense-waste overpacking at the repository). Scenario 4: MRS facility with all overpacking at the repository. Scenario 5: MRS facility with all overpacking at the repository and western fuel shipped directly to the repository. It is apparent that, with such a limited set of scenarios, determination of the optimum system was not an objective of this study. Furthermore, time constraints limited the level of detail to which facility designs could be developed; this level can best be characterized as ''preconceptual.'' These limitations are, however, compatible with the intent of the study, which was to make general comparisons between the several systems on an internally consistent basis
Encapsulation plant preliminary design, phase 2. Repository connected facility

International Nuclear Information System (INIS)

Kukkola, T.

2006-12-01

The disposal facility of the spent nuclear fuel will be located in Olkiluoto. The encapsulation plant is a part of the disposal facility. In this report, an independent encapsulation plant is located above the underground repository. In the encapsulation plant, the spent fuel is received and treated for disposal. In the fuel handling cell, the spent fuel assemblies are unloaded from the spent fuel transport casks and loaded into the disposal canisters. The gas atmosphere of the disposal canister is changed, the bolted inner canister lid is closed, and the electron beam welding method is used to close the lid of the outer copper canister. The disposal canisters are cleaned and transferred into the buffer store after the machining and inspection of the copper lid welds. From the buffer store, the disposal canisters are transferred into the repository spaces by help of the canister lift. All needed stages of operation are to be performed safely without any activity releases or remarkable personnel doses. The bentonite block interim storage is associated with the encapsulation plant. The bentonite blocks are made from bentonite powder. The bentonite blocks are used as buffer material around the disposal canister in the deposition hole. The average production rate of the encapsulation plant is 40 canisters per year. The nominal maximum production capacity is 100 canisters per year in one shift operation. (orig.)
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
The open research system: a web-based metadata and data repository for collaborative research

Science.gov (United States)

Charles M. Schweik; Alexander Stepanov; J. Morgan Grove

2005-01-01

Beginning in 1999, a web-based metadata and data repository we call the "open research system" (ORS) was designed and built to assist geographically distributed scientific research teams. The purpose of this innovation was to promote the open sharing of data within and across organizational lines and across geographic distances. As the use of the system...
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
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.
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
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
KiMoSys: a web-based repository of experimental data for KInetic MOdels of biological SYStems.

Science.gov (United States)

Costa, Rafael S; Veríssimo, André; Vinga, Susana

2014-08-13

The kinetic modeling of biological systems is mainly composed of three steps that proceed iteratively: model building, simulation and analysis. In the first step, it is usually required to set initial metabolite concentrations, and to assign kinetic rate laws, along with estimating parameter values using kinetic data through optimization when these are not known. Although the rapid development of high-throughput methods has generated much omics data, experimentalists present only a summary of obtained results for publication, the experimental data files are not usually submitted to any public repository, or simply not available at all. In order to automatize as much as possible the steps of building kinetic models, there is a growing requirement in the systems biology community for easily exchanging data in combination with models, which represents the main motivation of KiMoSys development. KiMoSys is a user-friendly platform that includes a public data repository of published experimental data, containing concentration data of metabolites and enzymes and flux data. It was designed to ensure data management, storage and sharing for a wider systems biology community. This community repository offers a web-based interface and upload facility to turn available data into publicly accessible, centralized and structured-format data files. Moreover, it compiles and integrates available kinetic models associated with the data.KiMoSys also integrates some tools to facilitate the kinetic model construction process of large-scale metabolic networks, especially when the systems biologists perform computational research. KiMoSys is a web-based system that integrates a public data and associated model(s) repository with computational tools, providing the systems biology community with a novel application facilitating data storage and sharing, thus supporting construction of ODE-based kinetic models and collaborative research projects.The web application implemented using Ruby
Evaluation of site-generated radioactive waste treatment and disposal methods for the Yucca Mountain repository

International Nuclear Information System (INIS)

Subramanian, C.V.; Jardine, L.J.

1989-01-01

This study identifies the sources of radioactive wastes that may be generated at the proposed high-level waste (HLW) repository at Yucca Mountain, NV, estimates the waste quantities and characteristics, compares technologies available for waste treatment and disposal, and develops recommended concepts for site-generated waste treatment and disposal. The scope of this study is limited to operations during the emplacement phase, in which 70,000 MTU of high-level waste will be received and emplaced at the proposed repository. The evaluations consider all radioactive wastes generated during normal operations in surface and underground facilities. Wastes generated as a result of accidents are not addressed; accidents that could result in large quantities of radioactive waste are expected to occur very infrequently and temporary, portable systems could be used for any necessary cleanup. The results of this study can be used to develop more definitive plans for managing the site-generated wastes and as a basis for the design of associated facilities at the proposed repository

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
Thermodynamic stability of actinide pyrochlore minerals in deep geologic repository environments

International Nuclear Information System (INIS)

Wang, YIFENG; Xu, HUIFANG

2000-01-01

Crystalline phases of pyrochlore (e.g., CaPuTi 2 O 7 , CaUTi 2 O 7 ) have been proposed as a durable ceramic waste form for disposal of high level radioactive wastes including surplus weapons-usable plutonium. In this paper, the authors use a linear free energy relationship to predict the Gibbs free energies of formation of pyrochlore phases (CaMTi 2 O 7 ). The Pu-pyrochlore phase is predicted to be stable with respect to PuO 2 , CaTiO 3 , and TiO 2 at room temperatures. Pu-pyrochlore is expected to be stable in a geologic repository where silica and carbonate components are absent or limited. The authors suggest that a repository in a salt formation be an ideal environment for disposal of high level, pyrochlore-based ceramic wastes. In such environment, adding CaO as a backfill will make pyrochlore minerals thermodynamically stable and therefore effectively prevent actinide release from these mineral phases
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
Applying system engineering methods to site characterization research for nuclear waste repositories

International Nuclear Information System (INIS)

Woods, T.W.

1985-01-01

Nuclear research and engineering projects can benefit from the use of system engineering methods. This paper is brief overview illustrating how system engineering methods could be applied in structuring a site characterization effort for a candidate nuclear waste repository. System engineering is simply an orderly process that has been widely used to transform a recognized need into a fully defined system. Such a system may be physical or abstract, natural or man-made, hardware or procedural, as is appropriate to the system's need or objective. It is a way of mentally visualizing all the constituent elements and their relationships necessary to fulfill a need, and doing so compliant with all constraining requirements attendant to that need. Such a system approach provides completeness, order, clarity, and direction. Admittedly, system engineering can be burdensome and inappropriate for those project objectives having simple and familiar solutions that are easily held and controlled mentally. However, some type of documented and structured approach is needed for those objectives that dictate extensive, unique, or complex programs, and/or creation of state-of-the-art machines and facilities. System engineering methods have been used extensively and successfully in these cases. The scientific methods has served well in ordering countless technical undertakings that address a specific question. Similarly, conventional construction and engineering job methods will continue to be quite adequate to organize routine building projects. Nuclear waste repository site characterization projects involve multiple complex research questions and regulatory requirements that interface with each other and with advanced engineering and subsurface construction techniques. There is little doubt that system engineering is an appropriate orchestrating process to structure such diverse elements into a cohesive, well defied project
Thermal modeling for a potential high-level nuclear waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Pruess, K.; Tsang, Y.

1994-03-01

Repository performance models based on numerical simulation of fluid and heat flows have recently been developed by several different groups. Model conceptualizations generally focus on large-scale average behavior. This comparison finds that current performance assessment (PA) models use generally similar approximations and parameters. Certain differences exist in some performance-relevant parameters, especially absolute permeabilities, characteristic curves, and thermal conductivities. These reflect present uncertainties about the most appropriate parameters applicable to Yucca Mountain and must be resolved through future field observations and laboratory measurements. For a highly heterogeneous fractured-porous hydrogeologic system such as Yucca Mountain, water infiltration through the unsaturated zone is expected to be dominated by highly localized phenomena. These include fast channelized flow along preferential paths in fractures, and frequent local ponding. The extended dry repository concept proposed by the Livermore group is reviewed. Predictions of large-scale drying around the repository on the average for large thermal loads cannot be taken to indicate that waste packages will not be contacted by liquid water, and that aqueous-phase transport of contaminants is not possible. Specifically, the authors find that modest water infiltration, on the order of a few millimeters per year, would be sufficient to overwhelm the vaporization capacity of the repository heat and inundate the waste packages within a time frame of a few thousand years. A preliminary analysis indicates that channelized flow of water may persist over large vertical distances. The vaporization-condensation cycle has a capacity for generating huge amounts of ponded water. A small fraction of the total condensate, if ponded and then episodically released, would be sufficient to cause liquid phase to make contact with the waste packages
Digital Preservation in the Context of Institutional Repositories

Science.gov (United States)

Hockx-Yu, Helen

2006-01-01

Purpose: To discuss the issues and challenges of digital preservation facing institutional repositories and to illustrate the Joint Information Systems Committee's (JISC) view on institutional repositories and its key initiatives in helping UK institutions address these issues. Design/methodology/approach: A combination of published work and JISC…
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
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
Accelerator assisted repositories, technical issue identification and economic assessment

Energy Technology Data Exchange (ETDEWEB)

Myers, T.; Favale, A.; Berwald, D. [Northrop Grumman Corp., Bethpage, NY (United States)

1995-12-31

An investigation (technical and economic) is presented to quantify the impact of accelerator assisted repository (AAR) system on the US national nuclear repository strategy. An overview of US spent fuel policy is presented which provides a means to comparatively assess competing spent fuel disposition technologies under investigation. The advantages of an AAR system are highlighted and discussed. A companion economic analysis is presented. The results indicate that although a US geologic waste repository will continue to be required, waste partitioning and accelerator transmutation of selected actinides, and long-lived fission products, can result in substantial benefits. (author) 18 refs.
Completeness and overlap in open access systems: Search engines, aggregate institutional repositories and physics-related open sources.

Science.gov (United States)

Tsay, Ming-Yueh; Wu, Tai-Luan; Tseng, Ling-Li

2017-01-01

This study examines the completeness and overlap of coverage in physics of six open access scholarly communication systems, including two search engines (Google Scholar and Microsoft Academic), two aggregate institutional repositories (OAIster and OpenDOAR), and two physics-related open sources (arXiv.org and Astrophysics Data System). The 2001-2013 Nobel Laureates in Physics served as the sample. Bibliographic records of their publications were retrieved and downloaded from each system, and a computer program was developed to perform the analytical tasks of sorting, comparison, elimination, aggregation and statistical calculations. Quantitative analyses and cross-referencing were performed to determine the completeness and overlap of the system coverage of the six open access systems. The results may enable scholars to select an appropriate open access system as an efficient scholarly communication channel, and academic institutions may build institutional repositories or independently create citation index systems in the future. Suggestions on indicators and tools for academic assessment are presented based on the comprehensiveness assessment of each system.
Thermo-hydro-mechanical processes in the nearfield around a HLW repository in argillaceous formations. Vol. I. Laboratory investigations

Energy Technology Data Exchange (ETDEWEB)

Zhang, Chun-Liang; Czaikowski, Oliver; Rothfuchs, Tilmann; Wieczorek, Klaus

2013-06-15

All over the world, clay formations are being investigated as host medium for geologic disposal of radioactive waste because of their favourable properties, such as very low hydraulic conductivity against fluid transport, good sorption capacity for retardation of radionuclides, and high potential of self-sealing of fractures. The construction of a repository, the disposal of heat-emitting high-level radioactive waste (HLW), the backfilling and sealing of the remaining voids, however, will inevitably induce mechanical (M), hydraulic (H), thermal (T) and chemical (C) disturbances to the host formation and the engineered barrier system (EBS) over very long periods of time during the operation and post-closure phases of the repository. The responses and resulting property changes of the clay host rock and engineered barriers are to be well understood, characterized, and predicted for assessing the long-term performance and safety of the repository.
The value and need for long term conservation of information regarding nuclear waste repositories

Energy Technology Data Exchange (ETDEWEB)

Eng, T. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Jensen, M. [Swedish Radiation Protection Inst., Stockholm (Sweden)

1993-12-31

An important question in safety assessment of all repositories where toxic waste is disposed is how long should information be available to society about the repository and its content? Future societies right to knowledge must be considered and actions must already today be taken to ensure that proper information conservation, transfer and retrieval are provided. Collection of relevant information must be planned for at the research, construction and the operational phase of a repository. One of the main areas for information conservation and transfer is to mitigate future human intrusion. A system for best possible mitigation of human intrusion should with the present knowledge comprise the following parts: (a) development of planning procedures for long-term conservation of gathered information (present and future national and international archives, markers etc.); (b) continuous follow up of the state-of-the-art of information media; (c) preparations for national rules and regulations on nuclear waste information; (d) participation in international cooperation on issues concerning nuclear waste information keeping, transfer and retrieval.
Backfilling and closure of the deep repository. Phase 3 - pilot tests to verify engineering feasibility. Geotechnical investigations made on unsaturated backfill materials

International Nuclear Information System (INIS)

Johannesson, Lars-Erik

2008-12-01

The investigations described in this report is a part of the third phase of the joint SKB-Posiva project 'Backfilling and Closure of the Deep Repository, BACLO'. The overall objective of the BACLO project is to develop backfilling concept for the deep repository that can be configured to meet SKB's and Posiva's requirements in the chosen repository sites. The project was divided into four phases, of which two have already been performed. The second phase of the BACLO project consisted of laboratory tests and deepened analyses of the investigated backfill materials and methods and resulted in recommendation to focus on the development and testing of the block placement concept with three alternative backfill materials. The third phase investigations comprise of laboratory and large-scale experiments aiming at testing the engineering feasibility of the concept. In addition, how site-specific constraints, backfilling method and materials affect the long-term functions of the barriers will be described and analysed in order to set design specifications for the backfill. The third phase of the BACLO project is divided into several subprojects. The work described in this report belongs to subproject 1 concerning processes during installation and saturation of the backfill that may affect the long-term function of the bentonite buffer and the backfill itself. One of the main functions of backfill is to restrict buffer expansion which can lead to decrease in buffer density in the deposition hole. The criterion used as a basis for the Baclo investigations was that the buffer density at saturation should not be below 1,950 kg/m 3 at the level of the canister. The same criterion was applied for the work described in this report. The upward swelling of the buffer and the enclosed compression of the backfill was first studied assuming that both the buffer and the backfill were saturated. The main objective of this work was to study a case where the buffer is fully saturated
Backfilling and closure of the deep repository. Phase 3 - pilot tests to verify engineering feasibility. Geotechnical investigations made on unsaturated backfill materials

Energy Technology Data Exchange (ETDEWEB)

Johannesson, Lars-Erik (Clay Technology AB, Lund (Sweden))

2008-12-15

The investigations described in this report is a part of the third phase of the joint SKB-Posiva project 'Backfilling and Closure of the Deep Repository, BACLO'. The overall objective of the BACLO project is to develop backfilling concept for the deep repository that can be configured to meet SKB's and Posiva's requirements in the chosen repository sites. The project was divided into four phases, of which two have already been performed. The second phase of the BACLO project consisted of laboratory tests and deepened analyses of the investigated backfill materials and methods and resulted in recommendation to focus on the development and testing of the block placement concept with three alternative backfill materials. The third phase investigations comprise of laboratory and large-scale experiments aiming at testing the engineering feasibility of the concept. In addition, how site-specific constraints, backfilling method and materials affect the long-term functions of the barriers will be described and analysed in order to set design specifications for the backfill. The third phase of the BACLO project is divided into several subprojects. The work described in this report belongs to subproject 1 concerning processes during installation and saturation of the backfill that may affect the long-term function of the bentonite buffer and the backfill itself. One of the main functions of backfill is to restrict buffer expansion which can lead to decrease in buffer density in the deposition hole. The criterion used as a basis for the Baclo investigations was that the buffer density at saturation should not be below 1,950 kg/m3 at the level of the canister. The same criterion was applied for the work described in this report. The upward swelling of the buffer and the enclosed compression of the backfill was first studied assuming that both the buffer and the backfill were saturated. The main objective of this work was to study a case where the buffer is
Some reflections on human intrusion into a nuclear waste repository

International Nuclear Information System (INIS)

Westerlind, M.

2002-01-01

This paper summarises some of the Swedish nuclear regulators' requirements and views related to intrusion into a repository for spent nuclear fuel, in the post-closure phase. The focus is however on experiences from the interaction with various stakeholders in the Swedish process for siting a repository. It is recognised that intrusion is not a major concern but that it is regularly raised in the debate, often in connection with issues related to retrievability. It is pointed out that more attention should be paid to the repository performance after an intrusion event, both in safety assessments and in communication with stakeholders, and not only address the immediate impacts to intruders. It is believed that international co-operation would be useful for developing methodologies for defining intrusion scenarios. (author)
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.
GaitaBase: Web-based repository system for gait analysis.

Science.gov (United States)

Tirosh, Oren; Baker, Richard; McGinley, Jenny

2010-02-01

The need to share gait analysis data to improve clinical decision support has been recognised since the early 1990s. GaitaBase has been established to provide a web-accessible repository system of gait analysis data to improve the sharing of data across local and international clinical and research community. It is used by several clinical and research groups across the world providing cross-group access permissions to retrieve and analyse the data. The system is useful for bench-marking and quality assurance, clinical consultation, and collaborative research. It has the capacity to increase the population sample size and improve the quality of 'normative' gait data. In addition the accumulated stored data may facilitate clinicians in comparing their own gait data with others, and give a valuable insight into how effective specific interventions have been for others. 2009 Elsevier Ltd. All rights reserved.
An ontology based information system for the management of institutional repository's collections

Science.gov (United States)

Tsolakidis, A.; Kakoulidis, P.; Skourlas, C.

2015-02-01

In this paper we discuss a simple methodological approach to create, and customize institutional repositories for the domain of the technological education. The use of the open source software platform of DSpace is proposed to build up the repository application and provide access to digital resources including research papers, dissertations, administrative documents, educational material, etc. Also the use of owl ontologies is proposed for indexing and accessing the various, heterogeneous items stored in the repository. Customization and operation of a platform for the selection and use of terms or parts of similar existing owl ontologies is also described. This platform could be based on the open source software Protégé that supports owl, is widely used, and also supports visualization, SPARQL etc. The combined use of the owl platform and the DSpace repository form a basis for creating customized ontologies, accommodating the semantic metadata of items and facilitating searching.
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)
Data vaults: a database welcome to scientific file repositories

NARCIS (Netherlands)

Ivanova, M.; Kargın, Y.; Kersten, M.; Manegold, S.; Zhang, Y.; Datcu, M.; Espinoza Molina, D.

2013-01-01

Efficient management and exploration of high-volume scientific file repositories have become pivotal for advancement in science. We propose to demonstrate the Data Vault, an extension of the database system architecture that transparently opens scientific file repositories for efficient in-database

Safeguards for geological repositories

International Nuclear Information System (INIS)

Fattah, A.

2000-01-01

substantially large. Change in social, economic, environmental and other scenarios might demand recovery of nuclear and other material from the repository sometime in the future. To this end, the Department of Safeguards has developed a policy paper to guide the planner, designer and operator to incorporate safeguards related features, as appropriate. In parallel, a programme for the Development of Safeguards for Final Disposal of Spent Fuel in Geological Repositories (SAGOR) was launched to foster technological advancement. The mission of SAGOR has been to ensure that the safeguards systems developed for the final disposal of spent fuel effectively meet the objectives of IAEA safeguards, optimise IAEA resources, and make best use of existing technologies while still meeting the requirements for safety and environmental protection. (author)
Assessment of Effectiveness of Geologic Isolation Systems: REFERENCE SITE INITIAL ASSESSMENT FOR A SALT DOME REPOSITORY

Energy Technology Data Exchange (ETDEWEB)

Harwell, M. A.; Brandstetter, A.; Benson, G. L.; Raymond, J. R.; Brandley, D. J.; Serne, R. J.; Soldat, J. K.; Cole, C. R.; Deutsch, W. J.; Gupta, S. K.; Harwell, C. C.; Napier, B. A.; Reisenauer, A. E.; Prater, L. S.; Simmons, C. S.; Strenge, D. L.; Washburn, J. F.; Zellmer, J. T.

1982-06-01

As a methodology demonstration for the Office of Nuclear Waste Isolation (ONWI), the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) Program conducted an initial reference site analysis of the long-term effectiveness of a salt dome repository. The Hainesville Salt Dome in Texas was chosen to be representative of the Gulf Coast interior salt domes; however, the Hainesville Site has been eliminated as a possible nuclear waste repository site. The data used for this exercise are not adequate for an actual assessment, nor have all the parametric analyses been made that would adequately characterize the response of the geosystem surrounding the repository. Additionally, because this was the first exercise of the complete AEGIS and WASTE Rock Interaction Technology (WRIT) methodology, this report provides the initial opportunity for the methodology, specifically applied to a site, to be reviewed by the community outside the AEGIS. The scenario evaluation, as a part of the methodology demonstration, involved consideration of a large variety of potentially disruptive phenomena, which alone or in concert could lead to a breach in a salt dome repository and to a subsequent transport of the radionuclides to the environment. Without waste- and repository-induced effects, no plausible natural geologic events or processes which would compromise the repository integrity could be envisioned over the one-million-year time frame after closure. Near-field (waste- and repository-induced) effects were excluded from consideration in this analysis, but they can be added in future analyses when that methodology development is more complete. The potential for consequential human intrusion into salt domes within a million-year time frame led to the consideration of a solution mining intrusion scenario. The AEGIS staff developed a specific human intrusion scenario at 100 years and 1000 years post-closure, which is one of a whole suite of possible scenarios. This scenario
Detailed design report for an operational phase panel-closure system

International Nuclear Information System (INIS)

1996-01-01

Under contract to Westinghouse Electric Corporation (Westinghouse), Waste Isolation Division (WID), IT Corporation has prepared a detailed design of a panel-closure system for the Waste Isolation Pilot Plant (WIPP). Preparation of this detailed design of an operational-phase closure system is required to support a Resource Conservation and Recovery Act (RCRA) Part B permit application and a non-migration variance petition. This report describes the detailed design for a panel-closure system specific to the WIPP site. The recommended panel-closure system will adequately isolate the waste-emplacement panels for at least 35 years. This report provides detailed design and material engineering specifications for the construction, emplacement, and interface-grouting associated with a panel-closure system at the WIPP repository, which would ensure that an effective panel-closure system is in place for at least 35 years. The panel-closure system provides assurance that the limit for the migration of volatile organic compounds (VOC) will be met at the point of compliance, the WIPP site boundary. This assurance is obtained through the inherent flexibility of the panel-closure system
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.
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.
Plan for safety case of spent fuel repository at Olkiluoto

International Nuclear Information System (INIS)

Vieno, T.; Ikonen, A.T.K.

2005-02-01

analyse the evolution of the disposal system from the emplacement of the first canisters in the repository over the various transient phases into the far future. Radiation safety and fulfilment of regulatory requirements will mainly be dealt with in the Biosphere assessment, Radionuclide transport (safety assessment) and Complementary evaluations of safety (e.g. natural analogues) reports. The Summary report draws together the key findings and arguments. According to the outlined overall schedule, new reports on Site, Characteristics of spent fuel, Canister design, Repository design, and Evolution of site and repository should be available by 2006. The central contents for the Safety Case interim reporting will then be provided by the Process report (published in 2004) and the Evolution report. By 2009, a first or second version of each main report of the Safety Case should already be available. The central contents for the outline and preliminary assessments of the Safety Case will then be provided by the Site, Process, Radionuclide transport and Complementary evaluations reports compiled between 2007 and 2009. The final reports for the Safety Case supporting the construction license application will be compiled in 2010-2012. The Safety Case Plan will be updated along the progress of the Safety Case, for example, in association with the interim reporting of 2006 and 2009. (orig.)
The deep geologic repository technology programme: toward a geoscience basis for understanding repository safety

International Nuclear Information System (INIS)

Jensen, M.R.

2007-01-01

Within the Deep Geologic Repository Technology Programme (DGRTP) several Geoscience activities are focused on advancing the understanding of groundwater flow system evolution and geochemical stability in a Canadian Shield setting as affected by long-term climate change. A key aspect is developing confidence in predictions of groundwater flow patterns and residence times as they relate to the safety of a deep geologic repository for used nuclear fuel waste. This is being achieved through a coordinated multi-disciplinary approach intent on: i) demonstrating coincidence between independent geo-scientific data; ii) improving the traceability of geo-scientific data and its interpretation within a conceptual descriptive model(s); iii) improving upon methods to assess and demonstrate robustness in flow domain prediction(s) given inherent flow domain uncertainties (i.e. spatial chemical/physical property distributions, boundary conditions) in time and space; and iv) improving awareness amongst geo-scientists as to the utility of various geo-scientific data in supporting a safety case for a deep geologic repository. This multi-disciplinary DGRTP approach is yielding an improved understanding of groundwater flow system evolution and stability in Canadian Shield settings that is further contributing to the geo-scientific basis for understanding and communicating aspects of DGR safety. (author)
SATORI: a system for ontology-guided visual exploration of biomedical data repositories.

Science.gov (United States)

Lekschas, Fritz; Gehlenborg, Nils

2018-04-01

The ever-increasing number of biomedical datasets provides tremendous opportunities for re-use but current data repositories provide limited means of exploration apart from text-based search. Ontological metadata annotations provide context by semantically relating datasets. Visualizing this rich network of relationships can improve the explorability of large data repositories and help researchers find datasets of interest. We developed SATORI-an integrative search and visual exploration interface for the exploration of biomedical data repositories. The design is informed by a requirements analysis through a series of semi-structured interviews. We evaluated the implementation of SATORI in a field study on a real-world data collection. SATORI enables researchers to seamlessly search, browse and semantically query data repositories via two visualizations that are highly interconnected with a powerful search interface. SATORI is an open-source web application, which is freely available at http://satori.refinery-platform.org and integrated into the Refinery Platform. nils@hms.harvard.edu. Supplementary data are available at Bioinformatics online.
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)
Methodology used for total system performance assessment of the potential nuclear waste repository at yucca mountain (USA)

International Nuclear Information System (INIS)

Devonec, E.; Sevougian, S.D.; Mattie, P.D.; Mcneish, J.A.; Mishra, S.

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. 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. 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 the performance of the repository when various natural or engineered barriers are assumed to be degraded. The objective of these analyses is to evaluate the performance of the potential repository system under conditions ranging from expected to highly unlikely, though physically possible conditions. (author)
Methodology used for total system performance assessment of the potential nuclear waste repository at yucca mountain (USA)

Energy Technology Data Exchange (ETDEWEB)

Devonec, E.; Sevougian, S.D.; Mattie, P.D.; Mcneish, J.A. [Duke Engineering and Services, Town Center Drive, Las Vegas (United States); Mishra, S. [Duke Engineering and Services, Austin, TX (United States)

2001-07-01

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. 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. 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 the performance of the repository when various natural or engineered barriers are assumed to be degraded. The objective of these analyses is to evaluate the performance of the potential repository system under conditions ranging from expected to highly unlikely, though physically possible conditions. (author)
Ground water movements around a repository. Rock mechanics analyses

International Nuclear Information System (INIS)

Ratigan, J.L.

1977-09-01

The determination and rational assessment of groundwater flow around a repository depends upon the accurate analysis of several interdependent and coupled phenomenological events occuring within the rock mass. In particular, the groundwater flow pathways (joints) are affected by the excavation and thermomechanical stresses developed within the rock mass, and the properties, of the groundwater are altered by the temperature perturbations in the rock mass. The objective of this report is to present the results of the rock mechanics analysis for the repository excavation and the thermally-induced loadings. Qualitative analysis of the significance of the rock mechanics results upon the groundwater flow is provided in this report whenever such an analysis can be performed. Non-linear rock mechanics calculations have been completed for the repository storage tunnels and the global repository domain. The rock mass has been assumed to possess orthoganol joint sets or planes of weakness with finite strength characteristics. In the local analyses of the repository storage tunnels the effects of jointorientation and repository ventilation have been examined. The local analyses indicated that storage room support requirements and regions of strength failure are highly dependent upon joint orientation. The addition of storage tunnel ventilation was noted to reduce regions of strength failure, particularly during the 30 year operational phase of the repository. Examination of the local stresses around the storage tunnels indicated the potential for perturbed hydraulic permeabilities. The permeabilities can be expected to be altered to a greater degree by the stresses resulting from excavation than from stresses which are thermally induced. The thermal loading provided by the instantaneous waste emplacement resulted in stress states and displacements quite similar to those provided by the linear waste emplacement sequence
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
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
Nuclear waste repository in basalt: preconceptual design guidelines

International Nuclear Information System (INIS)

1979-06-01

The development of the basalt waste isolation program parallels the growing need for permanent, environmentally safe, and secure means to store nuclear wastes. The repository will be located within the Columbia Plateau basalt formations where these ends can be met and radiological waste can be stored. These wastes will be stored such that the wastes may be retrieved from storage for a period after placement. After the retrieval period, the storage locations will be prepared for terminal storage. The terminal storage requirements will include decommissioning provisions. The facility boundaries will encompass no more than several square miles of land which will be above a subsurface area where the geologic makeup is primarily deep basaltic rock. The repository will receive, from an encapsulation site(s), nuclear waste in the form of canisters (not more than 18.5 feet x 16 inches in diameter) and containers (55-gallon drums). Canisters will contain spent fuel (after an interim 5-year storage period), solidified high-level wastes (HLW), or intermediate-level wastes (ILW). The containers (drums) will package the low-level transuranic wastes (LL-TRU). The storage capacity of the repository will be expanded in a time-phased program which will require that subsurface development (repository expansion) be conducted concurrently with waste storage operations. The repository will be designed to store the nuclear waste generated within the predictable future and to allow for reasonable expansion. The development and assurance of safe waste isolation is of paramount importance. All activities will be dedicated to the protection of public health and the environment. The repository will be licensed by the US Nuclear Regulatory Commission (NRC). Extensive efforts will be made to assure selection of a suitable site which will provide adequate isolation
Nuclear waste repository in basalt: preconceptual design guidelines

Energy Technology Data Exchange (ETDEWEB)

1979-06-01

The development of the basalt waste isolation program parallels the growing need for permanent, environmentally safe, and secure means to store nuclear wastes. The repository will be located within the Columbia Plateau basalt formations where these ends can be met and radiological waste can be stored. These wastes will be stored such that the wastes may be retrieved from storage for a period after placement. After the retrieval period, the storage locations will be prepared for terminal storage. The terminal storage requirements will include decommissioning provisions. The facility boundaries will encompass no more than several square miles of land which will be above a subsurface area where the geologic makeup is primarily deep basaltic rock. The repository will receive, from an encapsulation site(s), nuclear waste in the form of canisters (not more than 18.5 feet x 16 inches in diameter) and containers (55-gallon drums). Canisters will contain spent fuel (after an interim 5-year storage period), solidified high-level wastes (HLW), or intermediate-level wastes (ILW). The containers (drums) will package the low-level transuranic wastes (LL-TRU). The storage capacity of the repository will be expanded in a time-phased program which will require that subsurface development (repository expansion) be conducted concurrently with waste storage operations. The repository will be designed to store the nuclear waste generated within the predictable future and to allow for reasonable expansion. The development and assurance of safe waste isolation is of paramount importance. All activities will be dedicated to the protection of public health and the environment. The repository will be licensed by the US Nuclear Regulatory Commission (NRC). Extensive efforts will be made to assure selection of a suitable site which will provide adequate isolation.
Strategy for safety case development: impact of a volunteering approach to siting a japanese HLW repository

International Nuclear Information System (INIS)

Kitayama, K.; Ishiguro, K.; Takeuchi, M.; Tsuchi, H.; Kato, T.; Sakabe, Y.; Wakasugi, K.

2008-01-01

NUMO strategy for safety case development is constrained by a staged siting approach, which has been initiated by a call for volunteer municipalities to host the HLW repository. For each site, the safety case is an important factor to be considered at the selection steps which narrow down towards the preferred repository location. This is particularly challenging, however, as every site requires a tailored repository concept, with associated performance assessment and an individual site evaluation programme all of which evolve with gradually increasing understanding of the host environment. In order to maintain flexibility without losing focus, NUMO has developed a formalized tailoring procedure, termed the NUMO Structured Approach (NSA). The NSA guides the interaction of the key site characterisation, repository design and performance assessment groups and is facilitated by tools to help the decision making associated with the tailoring process (e.g. a requirements management system) and with comparison of siting and design options (e.g. multi-attribute analysis). Pragmatically, the post-closure safety case will initially emphasize near-field processes and a robust engineering barrier system, considering the limited geological information at early stages. This will be complemented by a more realistic assessment of total system performance, as needed to compare options. In addition, efforts to rigorously assess operational phase safety and the practicality of assuring quality of the constructed engineered barriers are components of the total safety case which are receiving particular attention now, as they may better discriminate between sites while information is still limited. (authors)
US Department of Energy Approach to Probabilistic Evaluation of Long-Term Safety for a Potential Yucca Mountain Repository

International Nuclear Information System (INIS)

Dr. R. Dyer; Dr. R. Andrews; Dr. A. Van Luik

2005-01-01

Regulatory requirements being addressed in the US geological repository program for spent nuclear fuel and high-level waste disposal specify probabilistically defined mean-value dose limits. These dose limits reflect acceptable levels of risk. The probabilistic approach mandated by regulation calculates a ''risk of a dose,'' a risk of a potential given dose value at a specific time in the future to a hypothetical person. The mean value of the time-dependent performance measure needs to remain below an acceptable level defined by regulation. Because there are uncertain parameters that are important to system performance, the regulation mandates an analysis focused on the mean value of the performance measure, but that also explores the ''full range of defensible and reasonable parameter distributions''...System performance evaluations should not be unduly influenced by...''extreme physical situations and parameter values''. Challenges in this approach lie in defending the scientific basis for the models selected, and the data and distributions sampled. A significant challenge lies in showing that uncertainties are properly identified and evaluated. A single-value parameter has no uncertainty, and where used such values need to be supported by scientific information showing the selected value is appropriate. Uncertainties are inherent in data, but are also introduced by creating parameter distributions from data sets, selecting models from among alternative models, abstracting models for use in probabilistic analysis, and in selecting the range of initiating event probabilities for unlikely events. The goal of the assessment currently in progress is to evaluate the level of risk inherent in moving ahead to the next phase of repository development: construction. During the construction phase, more will be learned to inform a new long-term risk evaluation to support moving to the next phase: accepting waste. Therefore, though there was sufficient confidence of safety
Archaeological data as a basis for repository marker design

International Nuclear Information System (INIS)

Kaplan, M.F.

1982-10-01

This report concerns the development of a marking system for a nuclear waste repository which is very likely to survive for 10,000 years. In order to provide a background on the subject, and for the preliminary design presented in this report, a discussion is presented about the issues involved in human interference with the repository system and the communication of information. A separate chapter summarizes six ancient man-made monuments including: materials, effects of associated textual information on our understanding of the monument, and other features of the ancient monument relevant to marking a repository site. The information presented in the two chapters is used to provide the basis and rationale for a preliminary marker system design presented in a final chapter. 86 refs., 22 figs., 1 tab
Archaeological data as a basis for repository marker design

Energy Technology Data Exchange (ETDEWEB)

Kaplan, M.F.

1982-10-01

This report concerns the development of a marking system for a nuclear waste repository which is very likely to survive for 10,000 years. In order to provide a background on the subject, and for the preliminary design presented in this report, a discussion is presented about the issues involved in human interference with the repository system and the communication of information. A separate chapter summarizes six ancient man-made monuments including: materials, effects of associated textual information on our understanding of the monument, and other features of the ancient monument relevant to marking a repository site. The information presented in the two chapters is used to provide the basis and rationale for a preliminary marker system design presented in a final chapter. 86 refs., 22 figs., 1 tab.

Completeness and overlap in open access systems: Search engines, aggregate institutional repositories and physics-related open sources.

Directory of Open Access Journals (Sweden)

Ming-Yueh Tsay

Full Text Available This study examines the completeness and overlap of coverage in physics of six open access scholarly communication systems, including two search engines (Google Scholar and Microsoft Academic, two aggregate institutional repositories (OAIster and OpenDOAR, and two physics-related open sources (arXiv.org and Astrophysics Data System. The 2001-2013 Nobel Laureates in Physics served as the sample. Bibliographic records of their publications were retrieved and downloaded from each system, and a computer program was developed to perform the analytical tasks of sorting, comparison, elimination, aggregation and statistical calculations. Quantitative analyses and cross-referencing were performed to determine the completeness and overlap of the system coverage of the six open access systems. The results may enable scholars to select an appropriate open access system as an efficient scholarly communication channel, and academic institutions may build institutional repositories or independently create citation index systems in the future. Suggestions on indicators and tools for academic assessment are presented based on the comprehensiveness assessment of each system.
VerSi - A Methodology for a Comparison of Potential Repository Sites

International Nuclear Information System (INIS)

Hund, Wilhelm

2010-09-01

In the year 2000 the moratorium on the exploration of the Gorleben salt dome as a potential repository for all kinds of radioactive waste became effective as a result of the consensus agreement between the Federal Government and the utilities about phasing out nuclear energy in Germany. All exploration activities were interrupted for at maximum ten years to clarify conceptual and safety relevant questions. A new set of safety requirements for the final disposal of heat-generating radioactive waste in deep geological formations was established in July 2009 by the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU). As the BMU intended to carry out a comparison of potential repository sites it was necessary to initiate the development of a methodology for the identification of the site with the highest level of safety. A comparison of different repository sites requires a tool ensuring most confident and objective criteria for the comparison, whereas up to present long-term safety analyses were focused on confirming the suitability of sites by meeting the protection objectives by the measures of dose and risk. Within the 2006 established project VerSi a methodology for comparing different sites in different host rocks will be developed on the basis of long-term safety analyses taking into account geoscientific databases, inventory of radioactive waste, waste containers, corresponding disposal concepts and the feasibility of appropriate backfilling and closure concepts. The development of the method is aiming at providing measures other than dose and risk for the evaluation of the level of safety. For testing the tools a HLW-repository hosted in a salt dome (Gorleben) will be compared with a generic HLW-repository in consolidated clay as a host rock. As until now in Germany no clay stone site has been investigated for hosting a HLW repository, the required data are transferred from international research projects and repository concepts
The RAGE Game Software Components Repository for Supporting Applied Game Development

Directory of Open Access Journals (Sweden)

Krassen Stefanov

2017-09-01

Full Text Available This paper presents the architecture of the RAGE repository, which is a unique and dedicated infrastructure that provides access to a wide variety of advanced technology components for applied game development. The RAGE project, which is the principal Horizon2020 research and innovation project on applied gaming, develops up to three dozens of software components (RAGE software assets that are reusable across a wide diversity of game engines, game platforms and programming languages. The RAGE repository provides storage space for assets and their artefacts and is designed as an asset life-cycle management system for defining, publishing, updating, searching and packaging for distribution of these assets. It will be embedded in a social platform for asset developers and other users. A dedicated Asset Repository Manager provides the main functionality of the repository and its integration with other systems. Tools supporting the Asset Manager are presented and discussed. When the RAGE repository is in full operation, applied game developers will be able to easily enhance the quality of their games by including selected advanced game software assets. Making available the RAGE repository system and its variety of software assets aims to enhance the coherence and decisiveness of the applied game industry.
Liquid Effluent Monitoring Information System (LEMIS) System Construction

International Nuclear Information System (INIS)

Adams, R.T.

1994-01-01

The liquid effluent sampling program is part of the effort to minimize adverse environmental impact during the cleanup operation at the Hanford Site. Of the 33 Phase I and Phase II liquid effluents, all streams actively discharged to the soil column will be sampled. The Liquid Effluent Monitoring Information System (LEMIS) is being developed as the organized information repository facility in support of the liquid effluent monitoring requirements of the Tri-Party Agreement. It is necessary to provide an automated repository into which the results from liquid effluent sampling will be placed. This repository must provide for effective retention, review, and retrieval of selected sample data by authorized persons and organizations. This System Construction document is the aggregation of the DMR P+ methodology project management deliverables. Together they represent a description of the project and its plan through four Releases, corresponding to the definition and prioritization of requirements defined by the user
A model for the analysis of a normal evolution scenarios for a deep geological granite repository for high-level radioactive waste

International Nuclear Information System (INIS)

Cormenzana Lopez, J.L.; Cunado, M.A.; Lopez, M.T.

1996-01-01

The methodology usually used to evaluate the behaviour of deep geological repositories for high-level radioactive wastes comprises three phases: Identification of factors (processes, characteristics and events) that can affect the repository. Generation of scenarios. In general, a normal evolution scenario (Reference Scenario) and various disruptive scenarios (earthquake, human intrusion, etc) are considered. Evaluation of the behaviour of the repository in each scenario. The normal evolution scenario taking into account all factors with a high probability of occurrence is the first to be analysed. The performance assessment of behaviour being carried out by ENRESA for the AGP Granite has led to the identification of 63 of these factors. To analyse repository behaviour in the normal evolution scenario, it is necessary to first of all create an integrated model of the global system. This is a qualitative model including the 63 factors identified. For a global view of a such a complex system, it is very useful to graphically display the relationship between factors in an Influence Diagram. This paper shows the Influence Diagram used in the analysis of the AGP Granite Reference Scenario. (Author)
The Pangea concept for an international radioactive waste repository

International Nuclear Information System (INIS)

Kurzeme, M.

1999-01-01

Pangea Resources Australia Pty. Ltd. is engaged in a study to investigate the feasibility of constructing and operating an international radioactive waste repository in Australia. Western Australia in particular has a unique combination of geology, topography and climate which makes it eminently suitable for a deep geological repository for the safe and permanent disposal of radioactive waste. Australia also has the political, social, legal and financial systems, together with the technical capability to make it acceptable as a host nation for an international repository. This paper reviews the origins of the Pangea concept, describes the high isolation approach to site selection, the Pangea integrated waste management system, together with its potential economic impact on Australia
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…
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
A Generic Safety Assessment Model for a Trench Type LILW Repository

International Nuclear Information System (INIS)

Lee, Youn-Myoung; Choi, Hee-Joo

2015-01-01

This program is ready for a total system performance assessment and is able to deterministically and probabilistically evaluate the nuclide release from a repository and farther transport into the geosphere and biosphere under various normal circumstances, disruptive events, and scenarios that can occur after a failure of waste packages with associated uncertainty. Despite the conceptual design of a trench type LILW repository system, all parameter values associated with the repository system were assumed for the time being, and the generic model developed through this study should be helpful because the evaluation of such releases is very important. A simple and effective model for a safety assessment of a conceptual trench repository system, in which an LILW that arises from a nuclear power plant and other sources, has been developed. The computer program based on this model has also been developed as a GoldSim template using the commercial GoldSim development tool
A Generic Safety Assessment Model for a Trench Type LILW Repository

Energy Technology Data Exchange (ETDEWEB)

Lee, Youn-Myoung; Choi, Hee-Joo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-05-15

This program is ready for a total system performance assessment and is able to deterministically and probabilistically evaluate the nuclide release from a repository and farther transport into the geosphere and biosphere under various normal circumstances, disruptive events, and scenarios that can occur after a failure of waste packages with associated uncertainty. Despite the conceptual design of a trench type LILW repository system, all parameter values associated with the repository system were assumed for the time being, and the generic model developed through this study should be helpful because the evaluation of such releases is very important. A simple and effective model for a safety assessment of a conceptual trench repository system, in which an LILW that arises from a nuclear power plant and other sources, has been developed. The computer program based on this model has also been developed as a GoldSim template using the commercial GoldSim development tool.
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.
Oceanographic Data Repositories: An Analysis of the International Situation

Directory of Open Access Journals (Sweden)

Fabiano Couto Corrêa da Silva

2017-04-01

Full Text Available The preservation and organization of oceanographic research data enables the scientific community to consult and reuse information of different kinds, and this is made possible by the repositories, meaning the services that facilitate data storage and dissemination. This paper reviews the current situation of oceanographic data repositories across different countries and evaluates them according to a series of indicators. The writers propose that although interest in storing and reusing oceanographic data has increased in recent years, the repositories are still in the process of developing their systems for processing, disseminating and reusing data. The repositories also differ in terms of architecture and the organizational level of the content they offer.
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
Postclosure safety assessment of a used fuel repository in sedimentary rock

International Nuclear Information System (INIS)

Gobien, M.; Garisto, F.; Hunt, N.; Kremer, E.

2014-01-01

The Nuclear Waste Management Organization (NWMO) is responsible for the implementation of Adaptive Phased Management (APM), the federally-approved plan for safe long-term management of Canada's used nuclear fuel. Under the APM plan, used nuclear fuel will ultimately be placed within a deep geological repository in a suitable rock formation. This paper summarizes an illustrative case study of the current multi-barrier design and postclosure safety of a deep geological repository in a hypothetical sedimentary Michigan Basin setting. The purpose of this postclosure safety assessment is to determine potential effects of the repository on the health and safety of persons and the environment. Results are compared against acceptance criteria established for the protection of persons and the environment from potential radiological and non-radiological hazards. (author)
Postclosure safety assessment of a used fuel repository in sedimentary rock

Energy Technology Data Exchange (ETDEWEB)

Gobien, M.; Garisto, F.; Hunt, N.; Kremer, E. [Nuclear Waste Management Organization, Toronto, ON (Canada)

2014-07-01

The Nuclear Waste Management Organization (NWMO) is responsible for the implementation of Adaptive Phased Management (APM), the federally-approved plan for safe long-term management of Canada's used nuclear fuel. Under the APM plan, used nuclear fuel will ultimately be placed within a deep geological repository in a suitable rock formation. This paper summarizes an illustrative case study of the current multi-barrier design and postclosure safety of a deep geological repository in a hypothetical sedimentary Michigan Basin setting. The purpose of this postclosure safety assessment is to determine potential effects of the repository on the health and safety of persons and the environment. Results are compared against acceptance criteria established for the protection of persons and the environment from potential radiological and non-radiological hazards. (author)
Dry storage systems using casks for long term storage in an AFR and repository

International Nuclear Information System (INIS)

Einfeld, K.; Popp, F.W.

1986-01-01

In conclusion it can be stated that two basic routes with respect to spent fuel storage casks are feasible. One is the Multiple Transport Cask, which with certain modifications can be upgraded to meet the criteria for intermediate storage. Its status is characterized by the licensing of several types of Castor Casks for an intermediate storage period of 30 years in the AFR Storage Facility of DWK at Gorleben in the FRG. The other one is the Final Disposal (Repository) Cask, which can be made suitable for long term storage before a final decision with respect to a repository application is taken. The licensing procedure for a Pilot Conditioning Facility with the Pollux Cask System as reference case will be initiated by DWK in the near future. Under the assumption that in addition to the present Multiple Transport/Storage Casks a license for a Final disposal Cask with respect to long term storage is available, the relative merits of different cask storage systems would have to be evaluated
Repository Planning, Design, and Engineering: Part II-Equipment and Costing.

Science.gov (United States)

Baird, Phillip M; Gunter, Elaine W

2016-08-01

Part II of this article discusses and provides guidance on the equipment and systems necessary to operate a repository. The various types of storage equipment and monitoring and support systems are presented in detail. While the material focuses on the large repository, the requirements for a small-scale startup are also presented. Cost estimates and a cost model for establishing a repository are presented. The cost model presents an expected range of acquisition costs for the large capital items in developing a repository. A range of 5,000-7,000 ft(2) constructed has been assumed, with 50 frozen storage units, to reflect a successful operation with growth potential. No design or engineering costs, permit or regulatory costs, or smaller items such as the computers, software, furniture, phones, and barcode readers required for operations have been included.
Surface facilities for geological deep repositories - Measures against dangers during construction and operation

International Nuclear Information System (INIS)

2013-09-01

This brochure published by the Swiss National Cooperative for the Disposal of Radioactive Waste (NAGRA) discusses the measures that are to be taken to address the dangers encountered during the construction and operation of deep geological repositories for nuclear wastes. Firstly, the operation of such repositories during the emplacement of nuclear wastes is discussed and examples of possible repositories for fuel rods and highly-radioactive waste are presented. Various emission-protection issues and safety measures to be taken during construction of such repositories are looked at as is the protection of ground water. Safety considerations during the operational phase are discussed, including inclusion methods used for the wastes and radiation protection. The handling of radioactive wastes, the recognition of dangers and measures to be taken to counteract them are discussed. Various possible accidents are looked at
Preliminary total-system analysis of a potential high-level nuclear waste repository at Yucca Mountain

International Nuclear Information System (INIS)

Eslinger, P.W.; Doremus, L.A.; Engel, D.W.; Miley, T.B.; Murphy, M.T.; Nichols, W.E.; White, M.D.; Langford, D.W.; Ouderkirk, S.J.

1993-01-01

The placement of high-level radioactive wastes in minded repositories deep underground is considered a disposal method that would effectively isolate these wastes from the environment for long periods of time. This report describes modeling performed at PNL for Yucca Mountain between May and November 1991 addressing the performance of the entire repository system related to regulatory criteria established by the EPA in 40 CFR Part 191. The geologic stratigraphy and material properties used in this study were chosen in cooperation with performance assessment modelers at Sandia National Laboratories (SNL). Sandia modeled a similar problem using different computer codes and a different modeling philosophy. Pacific Northwest Laboratory performed a few model runs with very complex models, and SNL performed many runs with much simpler (abstracted) models
Preliminary total-system analysis of a potential high-level nuclear waste repository at Yucca Mountain

Energy Technology Data Exchange (ETDEWEB)

Eslinger, P.W.; Doremus, L.A.; Engel, D.W.; Miley, T.B.; Murphy, M.T.; Nichols, W.E.; White, M.D. [Pacific Northwest Lab., Richland, WA (United States); Langford, D.W.; Ouderkirk, S.J. [Westinghouse Hanford Co., Richland, WA (United States)

1993-01-01

The placement of high-level radioactive wastes in mined repositories deep underground is considered a disposal method that would effectively isolate these wastes from the environment for long periods of time. This report describes modeling performed at PNL for Yucca Mountain between May and November 1991 addressing the performance of the entire repository system related to regulatory criteria established by the EPA in 40 CFR Part 191. The geologic stratigraphy and material properties used in this study were chosen in cooperation with performance assessment modelers at Sandia National Laboratories (SNL). Sandia modeled a similar problem using different computer codes and a different modeling philosophy. Pacific Northwest Laboratory performed a few model runs with very complex models, and SNL performed many runs with much simpler (abstracted) models.

The Hidden Risk Decisions in Waste Repository Regulation

International Nuclear Information System (INIS)

Frishman, Steve

2001-01-01

The move toward risk-informed, performance-based regulation of activities involving radioactive materials is becoming wide spread and broadly applied. While this approach may have some merit in specific applications in which there is a considerable body of experience, its strict application in regulation of geologic repositories for highly radioactive wastes may not be appropriate for this unproven and socially controversial technology. The U.S. Nuclear Regulatory Commission describes risk-informed, performance-based regulation as 'an approach in which risk insights, engineering analysis and judgement (eg. defense in depth), and performance history are used to (1) focus attention on the most important activities, (2) establish objective criteria based upon risk insights for evaluating performance, (3) develop measurable or calculable parameters for monitoring system and licensee performance, and (4) focus on the results as the primary basis for regulatory decision-making.' Both the risk-informed and performance-based elements of the approach are problematic when considering regulation of geologic repositories for highly radioactive wastes - an activity yet to be accomplished by any nation. In investigating potential sites for geologic repositories there will always be residual uncertainty in understanding the natural system and the events and processes that affect it. The more complex the natural system, the greater will be the uncertainty in both the data and the models used to describe the characteristics of the site's natural barriers, and the events and processes that could affect repository waste isolation. The engineered barriers also are subject to uncertainties that are important to the repository system. These uncertainties translate themselves into a range of probabilities that certain events or processes, detrimental to waste isolation, will occur. The uncertainties also translate to a range of consequences and magnitudes of consequences, should the
Data Vaults: a Database Welcome to Scientiﬁc File Repositories

NARCIS (Netherlands)

M.G. Ivanova (Milena); Y. Kargin (Yagiz); M.L. Kersten (Martin); S. Manegold (Stefan); Y. Zhang (Ying); M. Datcu (Mihai); D. Espinoza Molina

2013-01-01

textabstractEfficient management and exploration of high-volume scientific file repositories have become pivotal for advancement in science. We propose to demonstrate the Data Vault, an extension of the database system architecture that transparently opens scientific file repositories for efficient
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)
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
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
Source terms for analysis of accidents at a high level waste repository

International Nuclear Information System (INIS)

Mubayi, V.; Davis, R.E.; Youngblood, R.

1989-01-01

This paper describes an approach to identifying source terms from possible accidents during the preclosure phase of a high-level nuclear waste repository. A review of the literature on repository safety analyses indicated that source term estimation is in a preliminary stage, largely based on judgement-based scoping analyses. The approach developed here was to partition the accident space into domains defined by certain threshold values of temperature and impact energy density which may arise in potential accidents and specify release fractions of various radionuclides, present in the waste form, in each domain. Along with a more quantitative understanding of accident phenomenology, this approach should help in achieving a clearer perspective on scenarios important to preclosure safety assessments of geologic repositories. 18 refs., 3 tabs
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)
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)
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

This status report aims at describing and assessing the interactions of the radioactive waste emplaced in a low- and intermediate level waste (L/ILW) 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 arising principally from the heat generated by the waste and the setting of cement. - Rock-mechanical effects: i.e. effects arising from the mechanical disturbance to the rock caused by the excavation of the emplacement caverns 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. Deep geological repositories are designed to avoid or mitigate the impact of potentially detrimental repository-induced effects on long-term safety. For the repository under consideration in the present report, an assessment of those repository-induced effects that remain shows that detrimental chemical and mechanical impacts are largely confined to the rock adjacent to the excavations, thermal impacts are minimal and gas effects can be mitigated by appropriate design measures to reduce gas production and provide pathways for gas transport that limit gas pressure build-up (engineered gas transport system, or EGTS). Specific measures that are part of the current reference design are discussed in relation to their significance with respect to repository-induced effects. The disposal system described in this report provides a system of passive barriers with multiple safety functions. The disposal
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

This status report aims at describing and assessing the interactions of the radioactive waste emplaced in a low- and intermediate level waste (L/ILW) 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 arising principally from the heat generated by the waste and the setting of cement. - Rock-mechanical effects: i.e. effects arising from the mechanical disturbance to the rock caused by the excavation of the emplacement caverns 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. Deep geological repositories are designed to avoid or mitigate the impact of potentially detrimental repository-induced effects on long-term safety. For the repository under consideration in the present report, an assessment of those repository-induced effects that remain shows that detrimental chemical and mechanical impacts are largely confined to the rock adjacent to the excavations, thermal impacts are minimal and gas effects can be mitigated by appropriate design measures to reduce gas production and provide pathways for gas transport that limit gas pressure build-up (engineered gas transport system, or EGTS). Specific measures that are part of the current reference design are discussed in relation to their significance with respect to repository-induced effects. The disposal system described in this report provides a system of passive barriers with multiple safety functions. The disposal
Schematic designs for penetration seals for a reference repository in bedded salt

International Nuclear Information System (INIS)

Kelsall, P.C.; Case, J.B.; Meyer, D.; Coons, W.E.

1982-11-01

The isolation of radioactive wastes in geologic repositories requires that man-made penetrations such as shafts, tunnels, or boreholes are adequately sealed. This report describes schematic seal designs for a repository in bedded salt referenced to the straitigraphy of southeastern New Mexico. The designs are presented for extensive peer review and will be updated as site-specific conceptual designs when a site for a repository in salt has been selected. The principal material used in the seal system is crushed salt obtained from excavating the repository. It is anticipated that crushed salt will consolidate as the repository rooms creep close to the degree that mechanical and hydrologic properties will eventually match those of undisturbed, intact salt. For southeastern New Mexico salt, analyses indicate that this process will require approximately 1000 years for a seal located at the base of one of the repository shafts (where there is little increase in temperature due to waste emplacement) and approximately 400 years for a seal located in an access tunnel within the repository. Bulkheads composed of contrete or salt bricks are also included in the seal system as components which will have low permeability during the period required for salt consolidation
Study on a monitoring strategy to support decision making for geological repository closure

International Nuclear Information System (INIS)

Suyama, Yasuhiro; Tanabe, Hiromi; Eto, Jiro; Yoshimura, Kimitaka

2010-01-01

Japan currently plans to dispose of high-level radioactive wastes (vitrified HLWs) produced from the reprocessing of spent nuclear fuel in deep geological formations, in order to isolate the radioactive wastes from the human environment for tens of thousands of years. Such a geological repository must be designed to ensure operational safety and post-closure safety. Then, following the closure of the geological repository, post-closure safety will be provided by an engineered barrier system (EBS) and a natural barrier system (NBS) without relying on monitoring or institutional control. However, from a technical standpoint, monitoring has been required during backfilling in current studies. Additionally, there has been strong social pressure to continue monitoring during all the phases including post-closure. On the basis of the current situations, a monitoring strategy for geological disposal must be studied to ensure the long term safety of geological disposal. Focusing on decision making for geological repository closure, the authors have created a basic logical structure for the decision making process with the principles for ensuring safety and have developed a monitoring strategy based on the logical structure. The monitoring strategy is founded on three key aspects: the role of monitoring, boundary conditions of monitoring at the time of decision making, and a methodology for monitoring planning. Then, the monitoring strategy becomes a starting point of monitoring planning during site characterization, construction, operation and staged closure, as well as post-closure with institutional control, and of social science studies. (author)
Radioactive waste transport to a Nirex deep repository

International Nuclear Information System (INIS)

Bennett, D.; Appleton, P.R.; Eastman, C.R.

1989-01-01

Nirex is addressing the transport of radioactive wastes, repository construction materials, personnel and spoil as part of their development of a deep repository. An integrated transport system will be developed for wastes which may involve, road, rail and sea transport. The possible application and the scale of operation of the transport system is described. Environmental impact assessments will be carried out, and the proposed approach to these is described. A methodology for the assessment of transport safety has been established and the results of a preliminary assessment are given. (author)
Data Mining Learning Models and Algorithms on a Scada System Data Repository

Directory of Open Access Journals (Sweden)

Mircea Rîşteiu

2010-06-01

Full Text Available This paper presents three data mining techniques applied
on a SCADA system data repository: NaÄ³ve Bayes, k-Nearest Neighbor and Decision Trees. A conclusion that k-Nearest Neighbor is a suitable method to classify the large amount of data considered is made finally according to the mining result and its reasonable explanation. The experiments are built on the training data set and evaluated using the new test set with machine learning tool WEKA.
Nuclide release calculation in the near-field of a reference HLW repository

International Nuclear Information System (INIS)

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

2004-01-01

The HLW-relevant R and D program for disposal of high-level radioactive waste has been carried out at Korea Atomic Energy Research Institute (KAERI) since early 1997 in order to develop a conceptual Korea Reference Repository System for direct disposal of nuclear spent fuel by the end of 2007. A preliminary reference geologic repository concept considering such established criteria and requirements as waste and generic site characteristics in Korea was roughly envisaged in 2003 focusing on the near-field components of the repository system. According to above basic repository concept, which is similar to that of Swedish KBS-3 repository, the spent fuel is first encapsulated in corrosion resistant canisters, even though the material has not yet been determined, and then emplaced into the deposition holes surrounded by high density bentonite clay in tunnels constructed at a depth of about 500 m in a stable plutonic rock body. Not only to demonstrate how much a reference repository is safe in the generic point of view with several possible scenarios and cases associated with a preliminary repository concept by conducting calculations for nuclide release and transport in the near-field components of the repository, even though enough information has not been available that much yet, but also to show a methodology by which a generic safety assessment could be performed for further development of Korea reference repository concept, nuclide release calculation study strongly seems to be necessary
Long-Term Information Management (LTIM) of Safeguards Data at Geological Repositories

International Nuclear Information System (INIS)

Haddal, R.; Finch, R.; Baldwin, G.

2016-01-01

Full text: The International Atomic Energy Agency (IAEA) has noted that long-term information management (LTIM) of safeguards data at geological repositories will be a significant challenge in the future as information and records management systems evolve and permanent disposal of nuclear materials becomes a high-priority in many countries. Identifying approaches to how information on buried high-level nuclear waste will be managed, handled, organized, archived, read, interpreted, and secured for the long-term (1000 years after repository closure and beyond) will be key to safeguards at repositories). The purpose of this study is to explore various long-term information management systems and how they may or may not be adapted for geological repositories for high-level waste. The study will also examine what types of safeguards-related data should be included in such a system. The study will also consider hypotheses about future needs and analyze the pros and cons of very long-term information management. (author
Some concepts of model uncertainty for performance assessments of nuclear waste repositories

International Nuclear Information System (INIS)

Eisenberg, N.A.; Sagar, B.; Wittmeyer, G.W.

1994-01-01

Models of the performance of nuclear waste repositories will be central to making regulatory decisions regarding the safety of such facilities. The conceptual model of repository performance is represented by mathematical relationships, which are usually implemented as one or more computer codes. A geologic system may allow many conceptual models, which are consistent with the observations. These conceptual models may or may not have the same mathematical representation. Experiences in modeling the performance of a waste repository representation. Experiences in modeling the performance of a waste repository (which is, in part, a geologic system), show that this non-uniqueness of conceptual models is a significant source of model uncertainty. At the same time, each conceptual model has its own set of parameters and usually, it is not be possible to completely separate model uncertainty from parameter uncertainty for the repository system. Issues related to the origin of model uncertainty, its relation to parameter uncertainty, and its incorporation in safety assessments are discussed from a broad regulatory perspective. An extended example in which these issues are explored numerically is also provided
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
General conceptual design study for a high-level radioactive waste repository in a granite formation

International Nuclear Information System (INIS)

1982-01-01

The object of the general conceptual design study for a high level radioactive wastes repository in a deep lying granite formation is to ensure that technology available in 1980 is suitable for building, operating and finally closing such a repository. It is feasible to build and operate a 1000 m deep repository, located in a granite batholith, receiving 30000 AVM canisters (after 30 years surface cooling), the disposal rate being 1000 canisters per year. Cost of the operation amounts to 1,3% of the corresponding amount of electricity. The building, operating and final closing phases will take 81 years
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...

Approach to geologic repository post closure system performance assessment

International Nuclear Information System (INIS)

Pahwa, S.B.; Felton, W.; Duguid, J.O.

1992-01-01

An essential part of the license application for a geologic repository will be the demonstration of compliance with the standards set by the Environmental Protection Agency. The performance assessments that produce the demonstration must rely on models of various levels of detail. The most detailed of these models are needed for understanding thoroughly the complex physical and chemical processes affecting the behavior of the system. For studying the behavior of major components of the system, less detailed models are often useful. For predicting the behavior of the total system, models of a third kind may be needed. These models must cover all the important processes that contribute to the behavior of the system, because they must estimate the behavior under all significant conditions for 10,000 years. In addition, however, computer codes that embody these models must calculate very rapidly because of the EPA standard's requirement for probabilistic estimates, which will be produced by sampling thousands of times from probability distributions of parameters. For this reason, the total-system models must be less complex than the detailed-process and subsystem models. The total-system performance is evaluated through modeling of the following components: Radionuclide release from the engineered-barrier system. Fluid flow in the geologic units. Radionuclide transport to the accessible environment. Radionuclide release to the accessible environment and dose to man
Schematic designs for penetration seals for a repository in the Paradox Basin

International Nuclear Information System (INIS)

Kelsall, P.C.; Meyer, D.; Case, J.B.; Coons, W.E.

1985-12-01

The isolation of radioactive wastes in geologic repositories requires that human-made penetrations such as shafts, tunnels, or boreholes are adequately sealed. This report describes schematic seal designs for a repository in bedded salt referenced to the stratigraphy of the Paradox Basin. The designs are presented for extensive peer review and will be updated as conceptual designs if the Paraodx Basin is selected as a candidate repository site. The principal components used in the shaft seal system are concrete bulkheads interspersed with highly compacted bentonite-rich earth fill. In the repository-level tunnels and rooms, the principal material used in the seal system is crushed salt obtained from excavating the repository. It is anticipated that crushed salt will consolidate in response to closure of the repository rooms, to the degree that mechanical and hydrologic properties will eventually match those of undisturbed, intact salt. For Paradox Basin Cycle 6 salt, analyses indictate that this process will require approximately 300 years for a seal located at the base of one of the repository shafts (where there is little increase in temperature due to waste emplacement) and approximately 140 years for a seal located in a main passageway within the repository. These analyses are based on uncertain laboratory data regarding intact salt creep rates and crushed salt consolidation characteristics, and must be regarded as preliminary
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
Underground repository for radioactive wastes

International Nuclear Information System (INIS)

Cassibba, R.O.

1989-01-01

In the feasibility study for an underground repository in Argentina, the conceptual basis for the final disposal of high activity nuclear waste was set, as well as the biosphere isolation, according to the multiple barrier concept or to the engineering barrier system. As design limit, the container shall act as an engineering barrier, granting the isolation of the radionuclides for approximately 1000 years. The container for reprocessed and vitrified wastes shall have three metallic layers: a stainless steel inner layer, an external one of a metal to be selected and a thick intermediate lead layer preselected due to its good radiological protection and corrosion resistance. Therefore, the study of the lead corrosion behaviour in simulated media of an underground repository becomes necessary. Relevant parameters of the repository system such as temperature, pressure, water flux, variation in salt concentrations and oxidants supply shall be considered. At the same time, a study is necessary on the galvanic effect of lead coupled with different candidate metals for external layer of the container in the same experimental conditions. Also temporal evaluation about the engineering barrier system efficiency is presented in this thesis. It was considered the extrapolated results of corrosion rates and literature data about the other engineering barriers. Taking into account that corrosion is of a generalized type, the integrity of the lead shall be maintained for more than 1000 years and according to temporal evaluation, the multiple barrier concept shall retard the radionuclide dispersion to the biosphere for a period of time between 10 4 and 10 6 years. (Author) [es
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
Operational analysis supporting the definition of the repository/transportation interface

International Nuclear Information System (INIS)

Peterson, R.W.; Smith, L.A.; Wampler, J.A.

1985-06-01

This report discusses progress made to date in an on-going effort to analyze operations at the repository-transportation interface of the Mined Geologic Disposal System of the Salt Repository Project (SRP). The interface is where the two systems actually are in physical contact with one another. The overall intent of the on-going effort is to to evaluate several interface design concepts for the extent to which workers are exposed to radiation, for the time required to receive and process transportation casks, and for the associated capital and operating costs. The design criteria report will outline interface functional requirements, which when incorporated into the interfacing systems (transportation-repository receiving), will ensure their physical compatibility, their optimal operation, and their compliance with performance standards. The final design criteria report will subsequently serve as an input to the receiving facility design portions of the SRP System Design Description (SDD), and System Requirements Specifications (SRS), and to the transportation cask design specifications. 6 refs., 13 figs., 6 tabs
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)
Dose calculation for accident situations at WWR-S type spent nuclear fuel repository

International Nuclear Information System (INIS)

Margeanu, S.; Florescu, G.

2006-01-01

Full text: The Spent Nuclear Fuel Repository at IFIN-HH Bucharest (SNFR IFIN-HH) consists in four pools, repository hall, radiological monitoring system, ventilation system and auxiliary systems. At the moment the remaining activity in the repository is about 3500 Ci. Despite of the small activity, for emergency preparedness purposes, several accident scenarios, with a non zero probability of occurrence during the repository lifetime, have been postulated. Evaluations of radiological consequences to personnel, general public and environment, for each accident scenario have been performed. The radioactive inventory was evaluated with ORIGEN code from SCALE computer code system and radiological consequences were evaluated with COSYMA computer code. Assumptions for the source term determination, meteorological conditions and release, are presented. The calculated values of doses and risk are also presented. The impact of these accident scenarios on population and environment is also discussed. (authors)
Nuclear waste repository transparency technology test bed demonstrations at WIPP

International Nuclear Information System (INIS)

Betsill J, David; Elkins, Ned Z.; Wu, Chuan-Fu; Mewhinney, James D.; Aamodt, Paul

2000-01-01

Secretary of Energy, Bill Richardson, has stated that one of the nuclear waste legacy issues is ''The challenge of managing the fuel cycle's back end and assuring the safe use of nuclear power.'' Waste management (i.e., the back end) is a domestic and international issue that must be addressed. A key tool in gaining acceptance of nuclear waste repository technologies is transparency. Transparency provides information to outside parties for independent assessment of safety, security, and legitimate use of materials. Transparency is a combination of technologies and processes that apply to all elements of the development, operation, and closure of a repository system. A test bed for nuclear repository transparency technologies has been proposed to develop a broad-based set of concepts and strategies for transparency monitoring of nuclear materials at the back end of the fuel/weapons cycle. WIPP is the world's first complete geologic repository system for nuclear materials at the back end of the cycle. While it is understood that WIPP does not currently require this type of transparency, this repository has been proposed as realistic demonstration site to generate and test ideas, methods, and technologies about what transparency may entail at the back end of the nuclear materials cycle, and which could be applicable to other international repository developments. An integrated set of transparency demonstrations was developed and deployed during the summer, and fall of 1999 as a proof-of-concept of the repository transparency technology concept. These demonstrations also provided valuable experience and insight into the implementation of future transparency technology development and application. These demonstrations included: Container Monitoring Rocky Flats to WIPP; Underground Container Monitoring; Real-Time Radiation and Environmental Monitoring; Integrated level of confidence in the system and information provided. As the world's only operating deep geologic
Direct Investigations Of The Immobilization Of Radionuclides In The Alteration Phases Of Spent Nuclear Fuel

International Nuclear Information System (INIS)

Burns, Peter C.; Finch, Robert J.; Wronkiewicz, David J.

2003-01-01

radionuclides considered in the TSPA-VA (Total System Performance Analysis - Viability Assessment) Base Case Performance Analysis (CRWMS, 1998, cf. Table 3-14 in section 3.5.1) are of special concern because of their long half-lives, radiological toxicities, and potential mobilities under repository conditions. These are five actinide isotopes, Np-237, Pu-239, Pu-242, U-234, and Pa- 231, and four fission products, Tc-99, I-129, Se-79, and C-14. In addition, Am-241 is important because it is a parent of Np-237. An understanding of the behaviors of these elements under repository-relevant conditions is essential to safe disposal. Natural analogue studies of the mineral uraninite, UO2+x (an analogue for UO2 in spent fuel), as well as several laboratory-scale simulations, confirm that spent fuel is unstable under the moist, oxidizing conditions expected in the proposed repository at Yucca Mountain. Once containers are breached, alteration of the spent fuel m ay be rapid, with the most abundant alteration products being uranyl (U6+) phases. Shortly after groundwater or condensed water vapor contacts spent fuel in the proposed repository, uranyl phases are likely to be abundant in the vicinity of the spent fuel. Most of the uranyl phases that will form in the repository are already known as minerals from natural systems. Many of these uranyl phases can persist for thousands of years, as demonstrated by studies of natural analogues (Finch et al. 1996). It is likely that uranyl phases forming due to the alteration of spent fuel will incorporate many of the radionuclides contained in the spent fuel (Burns et al. 1997), thus having a profound impact upon the mobility of the radionuclides. Our ongoing research is leading to an understanding of the impact of incorporation of radionuclides into uranyl phases. Such information is essential to an understanding of the long-term performance of the geological repository. Knowledge of the crystal structures, chemistries, stabilities and
The Use of Underground Research Laboratories to Support Repository Development Programs. A Roadmap for the Underground Research Facilities Network.

Energy Technology Data Exchange (ETDEWEB)

MacKinnon, Robert J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-10-26

Under the auspices of the International Atomic Energy Agency (IAEA), nationally developed underground research laboratories (URLs) and associated research institutions are being offered for use by other nations. These facilities form an Underground Research Facilities (URF) Network for training in and demonstration of waste disposal technologies and the sharing of knowledge and experience related to geologic repository development, research, and engineering. In order to achieve its objectives, the URF Network regularly sponsors workshops and training events related to the knowledge base that is transferable between existing URL programs and to nations with an interest in developing a new URL. This report describes the role of URLs in the context of a general timeline for repository development. This description includes identification of key phases and activities that contribute to repository development as a repository program evolves from an early research and development phase to later phases such as construction, operations, and closure. This information is cast in the form of a matrix with the entries in this matrix forming the basis of the URF Network roadmap that will be used to identify and plan future workshops and training events.
Initial design process of the repository

International Nuclear Information System (INIS)

Osmanlioglu, A.E.

2001-01-01

The concept of the final disposal of high level wastes is to isolate the waste from the biosphere for extremely long periods of time by emplacement of wastes into deep stable geological formations. Several geological formations have been considered as candidate host environments for high level waste disposal and several techniques have been developed for repository design. In this study, interrelationships of main parameters of a general repository design have been defined and effective parameters are shown at each step. Initial design process is based on the long term stability of underground openings as disposal galleries. For this reason, this design process includes two main analyses: mechanical analysis and thermal analysis. Each of the analysis systems is directly related to each other by technical precautions. As a result of this design process, general information about the acceptable depth of the repository, layout and emplacement pattern can be taken. Final design study can be established on the result of initial design process. (author)
Final repository for spent nuclear fuel. Underground design Simpevarp, Layout D1

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-04-15

This report is a compilation of the results of the underground design work carried out in design phase D1 of the Repository Design Project within the Deep Repository Project for the Simpevarp site. Similar reports are also being produced for the Laxemar and Forsmark sites. The design phase coincides with the initial site investigation phase. The main purpose of phase D1 is to answer the question 'Can a final repository be accommodated within the designated site', but also to test the design methodology and provide feedback to the modelling project. Design was carried out in accordance with the methodology described in UDP (Underground Design Premises), SKB R-04-60, and was based on preliminary data from various disciplines in the site modelling project. The preliminary input data used were then cross-checked against data in the final Site Descriptive Model SDM v 1.2 and significant differences were integrated in the design work. The design results from each design topic were presented by the designer at presentation meetings for SKB's design management and the reviewers engaged by SKB for the specific topic. After the presentation meeting the designer wrote up the work reports for the topic in question. The work reports were then reviewed by SKB's review team. The results of the review were compiled in a statement that was submitted to the designer to be dealt with. In the statement the designer documented which comments were dealt with and how. This report is a compilation of the entire design phase D1 for Simpevarp. The 3D layout with coordinate lists for deposition holes and tunnels that was drawn to illustrate a possible layout was used in the Preliminary safety evaluation of the Simpevarp subarea and the hydro modelling of the Open Repository, both activities within the Deep Repository Project. According to current plans for the Swedish nuclear programme, the minimum required number of canister positions in the repository is estimated to be
The preliminary design and feasibility study of the spent fuel and high level waste repository in the Czech Republic

International Nuclear Information System (INIS)

Valvoda, Z.; Holub, J.; Kucerka, M.

1996-01-01

In the year 1993, began the Program of Development of the Spent Fuel and High Level Waste Repository in the Conditions of the Czech Republic. During the first phase, the basic concept and structure of the Program has been developed, and the basic design criteria and requirements were prepared. In the conditions of the Czech Republic, only an underground repository in deep geological formation is acceptable. Expected depth is between 500 to 1000 meters and as host rock will be granites. A preliminary variant design study was realized in 1994, that analyzed the radioactive waste and spent fuel flow from NPPs to the repository, various possibilities of transportation in accordance to the various concepts of spent fuel conditioning and transportation to the underground structures. Conditioning and encapsulation of spent fuel and/or radioactive waste is proposed on the repository site. Underground disposal structures are proposed at one underground floor. The repository will have reserve capacity for radioactive waste from NPPs decommissioning and for waste non acceptable to other repositories. Vertical disposal of unshielded canisters in boreholes and/or horizontal disposal of shielded canisters is studied. As the base term of the start up of the repository operation, the year 2035 has been established. From this date, a preliminary time schedule of the Project has been developed. A method of calculating leveled and discounted costs within the repository lifetime, for each of selected 5 variants, was used for economic calculations. Preliminary expected parametric costs of the repository are about 0,1 Kc ($0.004) per MWh, produced in the Czech NPPs. In 1995, the design and feasibility study has gone in more details to the technical concept of repository construction and proposed technologies, as well as to the operational phase of the repository. Paper will describe results of the 1995 design work and will present the program of the repository development in next period
Deep geological isolation of nuclear waste: numerical modeling of repository scale hydrology

International Nuclear Information System (INIS)

Dettinger, M.D.

1980-04-01

The Scope of Work undertaken covers three main tasks, described as follows: (Task 1) CDM provided consulting services to the University on modeling aspects of the study having to do with transport processes involving the local groundwater system near the repository and the flow of fluids and vapors through the various porous media making up the repository system. (Task 2) CDM reviewed literature related to repository design, concentrating on effects of the repository geometry, location and other design factors on the flow of fluids within the repository boundaries, drainage from the repository structure, and the eventual transport of radionucldies away from the repository site. (Task 3) CDM, in a joint effort with LLL personnel, identified generic boundary and initial conditions, identified processes to be modeled, and recommended a modeling approach with suggestions for appropriate simplifications and approximations to the problem and identifiying important parameters necessary to model the processes. This report consists of two chapters and an appendix. The first chapter (Chapter III of the LLL report) presents a detailed description and discussion of the modeling approach developed in this project, its merits and weaknesses, and a brief review of the difficulties anticipated in implementing the approach. The second chapter (Chapter IV of the LLL report) presents a summary of a survey of researchers in the field of repository performance analysis and a discussion of that survey in light of the proposed modeling approach. The appendix is a review of the important physical processes involved in the potential hydrologic transport of radionuclides through, around and away from deep geologic nuclear waste repositories
Initial demonstration of the NRC`s capability to conduct a performance assessment for a High-Level Waste Repository

Energy Technology Data Exchange (ETDEWEB)

Codell, R.; Eisenberg, N.; Fehringer, D.; Ford, W.; Margulies, T.; McCartin, T.; Park, J.; Randall, J.

1992-05-01

In order to better review licensing submittals for a High-Level Waste Repository, the US Nuclear Regulatory Commission staff has expanded and improved its capability to conduct performance assessments. This report documents an initial demonstration of this capability. The demonstration made use of the limited data from Yucca Mountain, Nevada to investigate a small set of scenario classes. Models of release and transport of radionuclides from a repository via the groundwater and direct release pathways provided preliminary estimates of releases to the accessible environment for a 10,000 year simulation time. Latin hypercube sampling of input parameters was used to express results as distributions and to investigate model sensitivities. This methodology demonstration should not be interpreted as an estimate of performance of the proposed repository at Yucca Mountain, Nevada. By expanding and developing the NRC staff capability to conduct such analyses, NRC would be better able to conduct an independent technical review of the US Department of Energy (DOE) licensing submittals for a high-level waste (HLW) repository. These activities were divided initially into Phase 1 and Phase 2 activities. Additional phases may follow as part of a program of iterative performance assessment at the NRC. The NRC staff conducted Phase 1 activities primarily in CY 1989 with minimal participation from NRC contractors. The Phase 2 activities were to involve NRC contractors actively and to provide for the transfer of technology. The Phase 2 activities are scheduled to start in CY 1990, to allow Sandia National Laboratories to complete development and transfer of computer codes and the Center for Nuclear Waste Regulatory Analyses (CNWRA) to be in a position to assist in the acquisition of the codes.
Long-term environmental impacts of geologic repositories

International Nuclear Information System (INIS)

Pigford, T.H.

1983-05-01

This paper summarizes a study of the long-term environmental impacts of geologic repositories for radioactive wastes. Conceptual repositories in basalt, granite, salt, and tuff were considered. Site-specific hydrological and geochemical parameters were used wherever possible, supplemented with generic parameters when necessary. Radiation doses to future maximally exposed individuals who use the contaminated groundwater and surface water were calculated and compared with a performance criterion of 10 -4 Sv/yr for radiation exposures from probable events. The major contributors to geologic isolation are the absence of groundwater if the repository is in natural salt, the slow dissolution of key radioelements as limited by solubility and by diffusion and convection in groundwater, long water travel times from the waste to the environment, and sorption retardation in the media surrounding the repository. In addition, dilution by surface water can considerably reduce the radiation exposures that result from the small fraction of the waste radioactivity that may ultimately reach the environment. Estimates of environmental impacts are made both for unreprocessed spent fuel and for reprocessing wastes. Accelerated dissolution of waste exposed to groundwater during the period of repository heating is also considered. This study of environmental impacts is a portion of a more comprehensive study of geologic waste disposal carried out by the Waste Isolation System Panel of the US National Research Council
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.
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.
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

Safety- and performance indicators for a generic deep geological repository in clay

International Nuclear Information System (INIS)

Resele, G.; Niemeyer, M.; Wilhelm, St.; Heimer, St.; Mohlfeld, M.; Eilers, G.; Preuss, J.; Wollrath, J.

2010-01-01

Document available in extended abstract form only. As a first step of an impartial survey for an optimal site selection for a deep geological repository in Germany, potentially suitable regions shall be identified and localised according to their suitability. During the early phases of such a site selection procedure the information about the properties of the host rock and the geological situation at the potential sites is not very precise. As site investigation procedures are both expensive and time-consuming, it is essential to identify those properties of the geological barrier system that are most relevant for long-term safety. Furthermore, adequate indicators have to be chosen that allow a simple but efficient assessment of the suitability of the potential regions. Definition and application of 'exclusion criteria' based on single parameter values, e.g. the hydraulic conductivity of the host rock, is inadequate because the long-term safety depends on the interaction of many features and properties of the barrier system. In a research project, indicators have been developed which depend on the most relevant properties of the geological barriers and estimate the overall performance of a repository system. The application of these indicators on the barrier properties which have been found during the investigations of potential repository sites in clay located in Germany, Switzerland and France demonstrates how, for instance, an unfavourably high hydraulic permeability of the clay can be compensated by a large vertical extension of the clay layer and small hydraulic gradients. Other indicators evaluate the importance of hydraulic discontinuities and define the minimal requirements on technical barriers like seals and backfill of emplacement tunnels. When the information of the radionuclide inventory and the biosphere, especially the diluting aquifer is included, the indicators allow the estimation of the resulting dose which matches the result of a
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
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
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
Development Support Environment of Business ApplicationsBased on a Multi-Grain-Size Repository

Science.gov (United States)

Terai, Koichi; Izumi, Noriaki; Yamaguchi, Takahira

In order to build the Web-based application as a shopping site on the Web, various ideas from the different viewpoints are required, such as enterprise modeling, workflow modeling, software development, and so on. From the above standpoint, this paper proposes an integrated environment to support the whole development process of analysis, design and implementation of business application. In order to reuse know-hows of various ideas in the business application development, we device a multi-grain-size repository, which consists of coarse-, middle-, and fine-grain-size repositories that correspond to the enterprise models, workflow models, and software models, respectively. We also provide a methodology that rebuilds heterogeneous information resources required for the business applications development into a multi-grain-size repository based on ontologies. The contents of the repositories are modeled by the is-a, has-a, and E-R relations, and described by the XML language. We have implemented Java-based prototype environment with the tools dealing with the multi-layered repository and confirmed that it supports us in various phases of business application development including business model manifestation, detailed business model definition and an implementation of business software applications.
Licensing process characteristics of Small Modular Reactors and spent nuclear fuel repository

Energy Technology Data Exchange (ETDEWEB)

Söderholm, Kristiina, E-mail: kristiina.soderholm@fortum.com [Fortum Power (Finland); Tuunanen, Jari, E-mail: jari.tuunanen@fortum.com [Fortum Power (Finland); Amaba, Ben, E-mail: baamaba@us.ibm.com [IBM Complex Systems (United States); Bergqvist, Sofia, E-mail: sofia.bergqvist@se.ibm.com [IBM Rational Software (Sweden); Lusardi, Paul, E-mail: plusardi@nuscalepower.com [NuScale Power (United States)

2014-09-15

for spent nuclear fuel, such as the one planned to be built to Olkiluoto, Finland, is based on modular design and phased construction. In this case the disposal tunnels, bentonite buffer and backfill and the disposal canisters can be considered as modules. Due to its phased construction the facility has similar licensing characteristics of SMRs. A common licensing process needs to be simple and clear to ensure the feasibility of construction and deployment of SMR's as well as the deep geological repositories. One of the important aspects of nuclear licensing is the compliance to licensing requirements. In a discrete and transparent matter, systems engineering (SE) and requirements engineering (RE) are discussed with the licensing development. The sheer number of licensing requirements is daunting, interconnected in a complex fashion and long-lasting. The process and tools play a critical role in the success of the licensing effort. A few proposed examples of combined SMR and deep repository licensing applications are discussed using SE and RE principles. A synergistic discussion on licensing models, nuclear licensing simplification, as well as international approach in licensing, will be needed in the future. This would be a natural continuation to the collaborative efforts in Europe underway for existing and new large reactors.
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)
TURVA-2012: Assessment of radionuclide release scenarios for the repository system

International Nuclear Information System (INIS)

Smith, Paul; Poteri, Antti; Nordman, Henrik; Cormenzana, Jose Luis; Snellman, Margit; Marcos, Nuria; Hjerpe, Thomas; Koskinen, Lasse

2014-01-01

TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR) and application for a construction licence for a repository for disposal of spent nuclear fuel at the Olkiluoto site in south-western Finland. This paper gives a summary of the analyses of the radionuclide release scenarios formulated in a companion paper, TURVA-2012: Formulation of Radionuclide Release Scenarios (Marcos, 2014). The scenarios and the analyses take into account major uncertainties in the initial state of the barriers and possible paths for the evolution of the repository system identified in a further paper: TURVA-2012: Performance Assessment (Hellae, 2014). For each scenario, calculation cases are analysed to evaluate compliance of the proposed repository with regulatory requirements on radiological protection, as well as to illustrate the impact of specific uncertainties or combinations of uncertainties on the calculated results. Each case illustrates different possibilities for how the repository might evolve and perform over time, taking into account uncertainties in the models and parameter values used to represent radionuclide release, retention and transport and, for biosphere assessment calculation cases, radiation exposure. The calculation cases each address a single, failed canister, where three possible modes of failure are considered: - The presence of an initial defect in the copper overpack of the canister that penetrates the overpack completely (subsequent corrosion of the insert may then lead to an enlargement of the defect). - Corrosion of the copper overpack, which occurs most rapidly in scenarios in which buffer density is reduced, e.g. by erosion. - Shear movements on fractures intersecting the deposition holes. However, the likelihood and consequences of more than one canister failure occurring during the assessment time fame are also considered, generally based on the findings from the single canister calculations. Quantitative
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.
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
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...
Compliance with NRC subsystem requirements in the repository licensing process

International Nuclear Information System (INIS)

Minwalla, H.

1994-01-01

Section 121 of the Nuclear Waste Policy Act of 1982 requires the Nuclear Regulatory Commission (Commission) to issue technical requirements and criteria, for the use of a system of multiple barriers in the design of the repository, that are not inconsistent with any comparable standard promulgated by the Environmental Protection Agency (EPA). The Administrator of the EPA is required to promulgate generally applicable standards for protection of the general environment from offsite releases from radioactive material in repositories. The Commission's regulations pertaining to geologic repositories are provided in 10 CFR part 60. The Commission has provided in 10 CFR 60.112 the overall post-closure system performance objective which is used to demonstrate compliance with the EPA high-level waste (HLW) disposal standard. In addition, the Commission has provided, in 10 CFR 60.113, subsystem performance requirements for substantially complete containment, fractional release rate, and groundwater travel time; however, none of these subsystem performance requirements have a causal technical nexus with the EPA HLW disposal standard. This paper examines the issue of compliance with the conflicting dual regulatory role of subsystem performance requirements in the repository licensing process and recommends several approaches that would appropriately define the role of subsystem performance requirements in the repository licensing process
Development of an object-oriented simulation code for repository performance assessment

International Nuclear Information System (INIS)

Tsujimoto, Keiichi; Ahn, J.

1999-01-01

As understanding for mechanisms of radioactivity confinement by a deep geologic repository improves at the individual process level, it has become imperative to evaluate consequences of individual processes to the performance of the whole repository system. For this goal, the authors have developed a model for radionuclide transport in, and release from, the repository region by incorporating multiple-member decay chains and multiple waste canisters. A computer code has been developed with C++, an object-oriented language. By utilizing the feature that a geologic repository consists of thousands of objects of the same kind, such as the waste canister, the repository region is divided into multiple compartments and objects for simulation of radionuclide transport. Massive computational tasks are distributed over, and executed by, multiple networked workstations, with the help of parallel virtual machine (PVM) technology. Temporal change of the mass distribution of 28 radionuclides in the repository region for the time period of 100 million yr has been successfully obtained by the code
The Management System for the Development of Disposal Facilities for Radioactive Waste

International Nuclear Information System (INIS)

2011-01-01

Currently, many Member States are safely operating near surface disposal facilities and some are in the initial or advanced stages of planning geological repositories. As for other nuclear facilities and their operational phase, all activities associated with the disposal of radioactive waste need to be carefully planned and systematic actions undertaken in order to maintain adequate confidence that disposal systems will meet performance as well as prescribed safety requirements and objectives. The effective development and application of a management system (integrating requirements for safety, protection of health and the environment, security, quality and economics into one coherent system) which addresses every stage of repository development is essential. It provides assurance that the objectives for repository performance and safety, as well as environmental and quality criteria, will be met. For near surface repositories, a management system also provides the opportunity to re-evaluate existing disposal systems with respect to new safety, environmental or societal requirements which could arise during the operational period of a facility. The topic of waste management and disposal continues to generate public interest and scrutiny. Implementation of a formal management system provides documentation, transparency and accountability for the various activities and processes associated with radioactive waste disposal. This information can contribute to building public confidence and acceptance of disposal facilities. The objective of this report is to provide Member States with practical guidance and relevant information on management system principles and expectations for management systems that can serve as a basis for developing and implementing a management system for three important stages; the design, construction/upgrading and operation of disposal facilities. To facilitate the understanding of management system implementation at the different stages of a
Understanding large scale groundwater flow to aid in repository siting

International Nuclear Information System (INIS)

Davison, C.C.; Brown, A.; Gascoyne, M.; Stevenson, D.R.; Ophori, D.U.

1996-01-01

Atomic Energy of Canada Limited (AECL) with support from Ontario Hydro has developed a concept for the safe disposal of Canada's nuclear fuel waste in a deep (500 to 1000 m) mined repository in plutonic rocks of the Canadian Shield. The disposal concept involves the use of multiple engineered and natural barriers to ensure long-term safety. The geosphere, comprised of the enclosing rock mass and the groundwater which occurs in cracks and pores in the rock, is expected to serve as an important natural barrier to the release and migration of wastes from the engineered repository. Although knowledge of the physical and chemical characteristics of the groundwater in the rock at potential repository sites is needed to help design the engineered barriers of the repository it can also be used to aid in repository siting, to take greater advantage of natural conditions in the geosphere to enhance its role as a barrier in the overall disposal system
gLibrary/DRI: A grid-based platform to host multiple repositories for digital content

International Nuclear Information System (INIS)

Calanducci, A.; Gonzalez Martin, J. M.; Ramos Pollan, R.; Rubio del Solar, M.; Tcaci, S.

2007-01-01

In this work we present the gLibrary/DRI (Digital Repositories Infrastructure) platform. gLibrary/DRI extends gLibrary, a system with a easy-to-use web front-end designed to save and organize multimedia assets on Grid-based storage resources. The main goal of the extended platform is to reduce the cost in terms of time and effort that a repository provider spends to get its repository deployed. This is achieved by providing a common infrastructure and a set of mechanisms (APIs and specifications) that the repository providers use to define the data model, the access to the content (by navigation trees and filters) and the storage model. DRI offers a generic way to provide all this functionality; nevertheless the providers can add specific behaviours to the default functions for their repositories. The architecture is Grid based (VO system, data federation and distribution, computing power, etc). A working example based on a mammograms repository is also presented. (Author)
Preliminary analyses of scenarios for potential human interference for repositories in three salt formations

International Nuclear Information System (INIS)

1985-10-01

Preliminary analyses of scenarios for human interference with the performance of a radioactive waste repository in a deep salt formation are presented. The following scenarios are analyzed: (1) the U-Tube Connection Scenario involving multiple connections between the repository and the overlying aquifer system; (2) the Single Borehole Intrusion Scenario involving penetration of the repository by an exploratory borehole that simultaneously connects the repository with overlying and underlying aquifers; and (3) the Pressure Release Scenario involving inflow of water to saturate any void space in the repository prior to creep closure with subsequent release under near lithostatic pressures following creep closure. The methodology to evaluate repository performance in these scenarios is described and this methodology is applied to reference systems in three candidate formations: bedded salt in the Palo Duro Basin, Texas; bedded salt in the Paradox Basin, Utah; and the Richton Salt Dome, Mississippi, of the Gulf Coast Salt Dome Basin
Borehole plugging of man-made accesses to a basalt repository: a preliminary study

International Nuclear Information System (INIS)

Taylor, C.L.; Anttonen, G.J.; O'Rourke, J.E.; Niccum, M.R.

1979-09-01

This report describes the status of work currently in progress for the Basalt Borehole Plugging Program (BBPP). The primary objectives of the BBPP outlined in this report have been met during this first phase of work. These objectives included: (1) the preparation of a preliminary list of candidate plug materials; (2) a description of available machinery capable of placing candidate plug materials; and (3) the development of physical and geochemical testing programs to help evaluate the chemical stability and physical properties of candidate plug materials. The most significant finding from work to date is that given reasonable regulatory criteria, nothing has been identified which would prevent design of a plug system to seal manmade openings leading to a nuclear waste repository in Columbia River basalt for significantly long periods of time (on the order of thousands of years). Work accomplished to date indicates that this plug system can be designed using both natural and manufactured materials and can be emplaced with existing placement machinery and modifications of that machinery. The objectives of Task II are to conduct laboratory tests to evaluate the suitability of preferred candidate materials for plugging boreholes in the proposed repository, select plug system(s), initiate preconceptual machinery design for the placement of materials in plug system(s), and prepare a preliminary Task II report. As with Task I project organization, Task II is divided into subtasks that are identified by written subtask work summaries
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

The calculated post-closure performance of a radioactive waste repository is generally quantified in terms of radiological dose or risk to humans, with safety being determined by whether the calculated exposure values are consistent with predetermined target criteria which are deemed to represent acceptable radiological hazards. Despite their general acceptance, however, dose and risk are not perfect measures of repository safety because, in order to calculate them, gross assumptions must be made for future human behaviour patterns. Such predictions clearly become increasingly uncertain as forecasts are made further into the future. As a consequence, there has been a growing interest in developing other ways of assessing repository safety which do not require assumptions to be made for future human behaviour. One proposed assessment method is to use the distributions of naturally-occurring chemical species in the environment, expressed either as concentrations or fluxes of elements, radionuclides or radioactivity, as natural safety indicators which may be compared with the PA predictions of repository releases. Numerous comparisons are possible between the repository and natural systems. The primary objective is to use the natural system to provide context to the hazard presented by the repository releases. Put simply, if it can be demonstrated that the flux to the biosphere from the repository is not significant compared with the natural flux from the geosphere, then its radiological significance should not be of great or priority concern. Natural safety indicators may be quantified on a site specific basis, using information derived from a repository site characterisation programme, and can be compared to the outputs from the associated site specific PAs. Such calculations and comparisons may be very detailed and might examine, for example, the spatial and temporal variations in the distributions and fluxes of naturally-occurring chemical species arising from
Technology needs for selecting and evaluating high-level waste repository sites in crystalline rock

International Nuclear Information System (INIS)

1988-12-01

This report describes properties and processes that govern the performance of the geological barrier in a nuclear waste isolation system in crystalline rock and the state-of-the-art in the understanding of these properties and processes. Areas and topics that require further research and development as well as technology needs for investigating and selecting repository sites are presented. Experiences from the Swedish site selection program are discussed, and a general investigation strategy is presented for an area characterization phase of an exploratory program in crystalline rocks. 255 refs., 65 figs., 10 tabs

Oxidation-reduction reactions. Overview and implications for repository studies

International Nuclear Information System (INIS)

Apted, Michael J.; Arthur, Randolph C.; Sasamoto, Hiroshi; Yui, Mikazu; Iwatsuki, Teruki

2001-02-01

The purpose of this report is to provide a survey and review on oxidation-reduction ('redox') reactions, with particular emphasis on implications for disposal of high-level waste (HLW) in deep geological formations. As an overview, the focus is on basic principles, problems, and proposed research related specifically to the assessment of redox for a HLW repository in Japan. For a more comprehensive treatment of redox and the myriad associated issues, the reader is directed to the cited textbooks used as primary references in this report. Low redox conditions in deep geological formations is a key assumption in the 'Second Progress Report on Research and Development for the Geological Disposal of HLW in Japan' (hereafter called H12'). The release behavior of multi-valent radioelements (e.g., Tc, Se, U, Pu, Np), as well as daughter radioelements of these radioelements, from a deep geological repository are sensitively related to redox conditions. Furthermore, the performance of certain barrier materials, such as overpack and buffer, may be impacted by redox conditions. Given this importance, this report summarizes some key topics for future technical studies supporting site characterization and repository performance as follows: To fully test the conceptual models for system Eh, it will be necessary to measure and evaluate trace element and isotopic information of both coexisting groundwater and reactive minerals of candidate rocks. Because of importance of volatile species (e.g., O 2 , H 2 etc.) in redox reactions, and given the high total pressure of a repository located 500 to 1000 meter deep, laboratory investigations of redox will necessarily require use of pressurized test devices that can fully simulate repository conditions. The stability (redox capacity) of the repository system with respect to potential changes in redox boundary condition induced by oxidizing waters intrusion should be established experimentally. An overall conceptual model that unifies
The impact of thermal loading on repository performance at Yucca Mountain

International Nuclear Information System (INIS)

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

1992-01-01

In the unsaturated zone at Yucca Mountain, liquid flow along preferential fracture pathways is the only credible mechanism capable of bringing water to waste packages and transporting radionuclide to the water table. Three categories of features or mechanisms will mitigate the impact of flow along preferential fracture pathways: (1) discontinuity in fracture pathways, (2) liquid-phase dispersion in fracture networks, and (3) fracture-matrix interaction. For repository areal power densities (APDs) that are too low to result in significant boiling or rock dry-out effects, the primary mode of fracture-matrix interaction is matrix imbibition. For high APDs, boiling and enhanced matrix imbibition due to rock dry-out significantly add to the capacity of the unsaturated zone to retard fracture-dominated flow. With the use of V-TOUGH code, hydrothermal flow calculations are made for a range of APDs and spent fuel ages. For APD > 20 kW/acre, repository-heat-generated flow of vapor and liquid in fractures is found to dominate the ambient hydrological system. For high APDs, boiling conditions can persist for 10,000 yr or longer and rock-dry benefits for at least 100,000 yr
Process for selecting a site for Canada's deep geological repository for used nuclear fuel

International Nuclear Information System (INIS)

Facella, J.; Belfadhel, M.B.

2011-01-01

The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management, the approach selected by the Government of Canada for long-term management of used nuclear fuel waste generated by Canadian nuclear reactors. The ultimate objective of Adaptive Phased Management is the centralized containment and isolation of Canada's used nuclear fuel in a Deep Geological Repository in a suitable crystalline or sedimentary rock formation at a depth of about 500m. The repository will consist of a series of access and service shafts and a series of tunnels leading to placement rooms where used fuel will be placed and sealed in competent rock using a multi-barrier system which includes long lived specially designed containers, sealing materials such as bentonite and the rock itself. The used fuel will be monitored throughout all phases of implementation and will also remain retrievable for an extended period of time. In May 2010, the NWMO published the site selection process that serves as the road map to decision-making on the location for the deep geological repository. NWMO initiated the process with a first stage that invites communities to learn more about the project and the site selection process. NWMO is actively building awareness of the project and, on request of communities, is delivering briefings, supporting community capacity building and undertaking high-level screenings of site suitability. The paper provides a brief description of: Adaptive Phased Management including the deep geological repository which is its ultimate goal, and the design of the site selection process, and importantly the approach to assessing the suitability of sites from both a social and technical perspective. The paper will outline how NWMO sought to develop a socially-acceptable site selection process as a firm foundation for future decisions on siting. Through a two-year collaborative process, NWMO sought to understand the expectations of
Integrated management data system for radioactive waste repositories (SGI3R) - development of the inventory module

International Nuclear Information System (INIS)

Silva, Fabio; Tello, Cledola Cassia O. de

2011-01-01

In Brazil, CNEN is responsible for the intermediate and final storage of radioactive waste generated in the country. The CDTN/CNEN coordinates the RBMN Project for the implementation of the National Repository for disposal radioactive waste of low- and intermediate-level. The results of this Project should be presented so that all data being easily retrievable and useful for all institutions involved, including the regulators. To achieve this goal it was developed at the Waste Management Department - SEGRE/CDTN - a management database system, called 'Integrated Management System for the Management of Repository for Radioactive Waste' (SGI3R). The System consists of relational tables, forms and reports, preserving all available information, avoiding duplication of efforts, additional costs, and it will additionally give support to improve the management of RBMN Project. This paper presents a summary of this development with emphasis on the INVENTORY Module. The data from the inventory of disused sealed sources, which are stored in CDTN, were used to test the functionality of this module and of the SGI3R. These sources were categorized according to guidelines of the IAEA, and it was also presented how they should be safely managed over time. (author)
The study on safety facility criteria for radioactive waste repository

International Nuclear Information System (INIS)

Lee, S. H.; Choi, M. H.; Han, S. H. and others

1992-12-01

The radioactive waste repository are necessary to install the engineered safety systems to secure the safety for operation of the repository in the event of fire and earthquake. Since the development of safety facility criteria requires a thorough understanding about the characteristics of the engineered safety systems, we should investigate by means of literature survey and visit SKB. In particular, definition, composition of the systems, functional requirement of the systems, engineered safety systems of foreign countries, system design, operation and maintenance requirement should be investigated : fire protection system, ventilation system, drainage system, I and C system, electric system, radiation monitoring system. This proposed criteria consist of purpose, scope of application, ventilation system, fire protection system, drainage system, electric system and this proposed criteria can be applied as a basic reference for the final criteria
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.
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.
Bases for an environmental liability management system: application to a repository for radioactive waste

International Nuclear Information System (INIS)

Tostes, Marcelo Mallat

1999-03-01

This thesis aims the establishment of conceptual bases for the development of Environmental Liability Management System - instruments designed to provide financial and managerial coverage to financial liabilities arising from activities that impact the environment. The document analyses the theories that link the evolution of economic thought and environment, as a means of establish the necessary framework for the development of up-to-date environmental policy instruments. From these concepts and from the analysis of environmental liability system being implemented in several countries, the bases for environmental liability systems development are drawn. Finally, a study is carried out on the application of these bases for the development of an environmental liability management system for a radioactive waste repository. (author)
Preliminary Criticality Calculation on Conceptual Deep Borehole Disposal System for Trans-metal Waste during Operational Phase

International Nuclear Information System (INIS)

Kim, In Young; Choi, Heui Joo; Cho, Dong Geun

2013-01-01

The primary function of any repository is to prevent spreading of dangerous materials into surrounding environment. In the case of high-level radioactive waste repository, radioactive material must be isolated and retarded during sufficient decay time to minimize radiation hazard to human and surrounding environment. Sub-criticality of disposal canister and whole disposal system is minimum requisite to prevent multiplication of radiation hazard. In this study, criticality of disposal canister and DBD system for trans-metal waste is calculated to check compliance of sub-criticality. Preliminary calculation on criticality of conceptual deep borehole disposal system and its canister for trans-metal waste during operational phase is conducted in this study. Calculated criticalities at every temperature are under sub-criticalities and criticalities of canister and DBD system considering temperature are expected to become 0.34932 and 0.37618 approximately. There are obvious limitations in this study. To obtain reliable data, exact elementary composition of each component, system component temperature must be specified and applied, and then proper cross section according to each component temperature must be adopted. However, many assumptions, for example simplified elementary concentration and isothermal component temperature, are adopted in this study. Improvement of these data must be conducted in the future work to progress reliability. And, post closure criticality analyses including geo, thermal, hydro, mechanical, chemical mechanism, especially fissile material re-deposition by precipitation and sorption, must be considered to ascertain criticality safety of DBD system as a future work
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
Evaluation of the Overall Costs for the Croatian Repository: Varying Site, Design and Financial Parameters

International Nuclear Information System (INIS)

Kucar-Dragicevic, S.; Subasic, D.; Lebegner, J.

2000-01-01

Preliminary preparations for the construction of a LILW repository in Croatia included a number of activities and projects related to the siting process, safety assessment, disposal technology and repository design, and public acceptance issues. Costs evaluations have always been a part of the developing project documentation. However, only the estimates of the facility construction and equipment acquisition costs had been included, while other costs associated with the project development and management have not been considered up to now. For the first time the infrastructure status at the potential sites has been evaluated, and the costs of the repository operations as well as the post-closure management has been estimated. Cost parameters have been considered from both technical and fiscal points of view, comparing their relative influence on the overall repository costs. Assessment of the total project costs in eight cases for the four preferential sites and two repository designs gave a clearer picture of the development and management costs differences for the considered options. Without considerations of the operational and post-operational repository management expenses, the total project costs appear to have been heavily underestimated. Also, while the construction costs for the tunnel and the surface type repositories are significantly different, this influence of the repository type on the total project costs becomes far less important when the later phases management expenses are added. Finally, the role of fiscal parameters may further diminish the site and technology impacts on the overall costs. (author)
The impact of repository heat on thermo-hydrological performance at Yucca Mountain

International Nuclear Information System (INIS)

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

1993-09-01

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 a waste package (WP), accelerate its failure rate, and eventually transport radionuclides to the water table. These analyses have demonstrated that the only significant source of liquid water is nonequilibrium fracture flow from: (1) meteoric sources, (2) condensate drainage generated under boiling conditions, and (3) condensate drainage generated under sub-boiling conditions. The first source of liquid water arises from the ambient system; the second and third sources are generated by repository heat. Buoyant vapor flow, occurring either on a sub-repository scale or on a mountain scale, may play an important role in the generation of the second and third sources of liquid water. By considering a wide range in bulk permeability, k b , the authors identify the threshold k b (called k b hyd ) at which buoyant, vapor convection begins to dominate hydrological behavior, and the threshold k b (called k b th ) at which this convection begins to dominate thermal behavior. They find that k b th is generally an order of magnitude larger than k b hyd and that the development of a large above-boiling zone suppresses the effects of buoyant vapor flow. Of particular concern are conditions that promote the focusing of vapor flow and condensate drainage, which could result in persistent two-phase conditions (often referred to as the heat-pipe effect) in the vicinity of WPs. The results of this study underscore the need for in situ heater tests to help diagnose the potential for the major repository-heat-driven sources of fracture flow
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
SBR-Blood: systems biology repository for hematopoietic cells.

Science.gov (United States)

Lichtenberg, Jens; Heuston, Elisabeth F; Mishra, Tejaswini; Keller, Cheryl A; Hardison, Ross C; Bodine, David M

2016-01-04

Extensive research into hematopoiesis (the development of blood cells) over several decades has generated large sets of expression and epigenetic profiles in multiple human and mouse blood cell types. However, there is no single location to analyze how gene regulatory processes lead to different mature blood cells. We have developed a new database framework called hematopoietic Systems Biology Repository (SBR-Blood), available online at http://sbrblood.nhgri.nih.gov, which allows user-initiated analyses for cell type correlations or gene-specific behavior during differentiation using publicly available datasets for array- and sequencing-based platforms from mouse hematopoietic cells. SBR-Blood organizes information by both cell identity and by hematopoietic lineage. The validity and usability of SBR-Blood has been established through the reproduction of workflows relevant to expression data, DNA methylation, histone modifications and transcription factor occupancy profiles. Published by Oxford University Press on behalf of Nucleic Acids Research 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Important parameters in the performance of a potential repository at Yucca Mountain (TSPA-1995)

International Nuclear Information System (INIS)

Atkins, J.E.; Sevougian, S.D.; Lee, J.H.; Andrews, R.W.; McNeish, J.A.

1996-01-01

A total system performance assessment (TSPA) was conducted to determine how a potential repository at Yucca Mountain would behave. Using the results of this TSPA, regression was done to determine which parameters had the most important effect on the repository performance. These results were consistent with the current conceptual understanding of the repository
Stress, strain, and temperature induced permeability changes in potential repository rocks

International Nuclear Information System (INIS)

Heard, H.C.; Duba, A.

1977-01-01

Work is in progress to assess the permeability characteristics of coarse-grained igneous rocks as affected by pressure, deviatoric stress, and temperature. In order to predict the long-term behavior of these rocks, both virgin and fractured, permeability and all principal strains resulting from an imposed deviatoric stress under various simulated lithostatic pressures are being measured. In addition, compressional as well as shear velocities and electrical conductivity are being evaluated along these principal directions. These simultaneous measurements are being made initially at 25 0 C on a 15 cm diameter by 30 cm long sample in a pressure apparatus controlled by a mini-computer. Correlation of these data with similar field observations should then allow simplified exploration for a suitable repository site as well as the prediction of the response of a mined cavity with both distance and time at this site. After emplacement of the waste canisters, the mechanical stability and hydrologic integrity of this mined repository will be directly influenced by the fracturing of the surrounding rock which results from local temperature differences and the thermal expansion of that rock. Temperatures (and, hence, these differences) in the vicinity of the repository are expected to be affected by the presence of pore fluids (single- or two-phase) in the rock, the heat capacity and the thermal conductivity of this system. In turn, these are all dependent upon lithostatic pressure, pore pressure, and stress. Thermal expansion (and fracturing) will also be affected by the lithostatic (and effective) pressure, the deviatoric stress field, and the initial anisotropy of the rock
Optimizing Resources for Trustworthiness and Scientific Impact of Domain Repositories

Science.gov (United States)

Lehnert, K.

2017-12-01

Domain repositories, i.e. data archives tied to specific scientific communities, are widely recognized and trusted by their user communities for ensuring a high level of data quality, enhancing data value, access, and reuse through a unique combination of disciplinary and digital curation expertise. Their data services are guided by the practices and values of the specific community they serve and designed to support the advancement of their science. Domain repositories need to meet user expectations for scientific utility in order to be successful, but they also need to fulfill the requirements for trustworthy repository services to be acknowledged by scientists, funders, and publishers as a reliable facility that curates and preserves data following international standards. Domain repositories therefore need to carefully plan and balance investments to optimize the scientific impact of their data services and user satisfaction on the one hand, while maintaining a reliable and robust operation of the repository infrastructure on the other hand. Staying abreast of evolving repository standards to certify as a trustworthy repository and conducting a regular self-assessment and certification alone requires resources that compete with the demands for improving data holdings or usability of systems. The Interdisciplinary Earth Data Alliance (IEDA), a data facility funded by the US National Science Foundation, operates repositories for geochemical, marine Geoscience, and Antarctic research data, while also maintaining data products (global syntheses) and data visualization and analysis tools that are of high value for the science community and have demonstrated considerable scientific impact. Balancing the investments in the growth and utility of the syntheses with resources required for certifcation of IEDA's repository services has been challenging, and a major self-assessment effort has been difficult to accommodate. IEDA is exploring a partnership model to share
Overview of the current CRWMS repository design

International Nuclear Information System (INIS)

Daniel, R.B.; Teraoka, G.M.

1998-01-01

This paper summarizes the current design for a potential geologic repository for spent fuels and high-level wastes at Yucca Mountain, Nevada. The objective of the paper is to present the key design features of the Mined Geologic Disposal System (MGDS) surface facilities and MGDS subsurface facilities. The paper describes the following: surface layout; waste handling operations design; subsurface design; and the underground transport and emplacement design. A more detailed presentation of key features is provided in the ''Reference design description for a geologic repository'' which is located on the YMP Homepage at www.ymp.gov
Achieving transparency in the total system performance assessment of a potential high level radioactive waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Bailey, J.; Rickertsen, L.; Cotton, T.

1999-01-01

This paper has presented an approach to quantitative assessment of the degree of postclosure defense-in-depth provided by the reference system of the VA (Viability Assessment). This approach identifies principal barriers, assesses barriers for common uncertainty and failure mode, conducts barrier neutralization analyses, and evaluates overall defense-in-depth. The neutralization approach of step 3 is particularly useful in untangling the contributions of various barriers to the results calculated by performance assessments. In fact, it provides the only way of assessing the contribution of barriers that are fully redundant with one another. The approach has been applied to the VA reference system. It shows how the natural transport barriers contribute to performance of the system. Since their individual contributions are redundant, uncertainties in those individual contributions are reduced in importance. The analyses also suggest uncertainties common to both of these barriers are important to the safety assessment. Thus, the approach appears to be capable of determining the contribution of the principal barriers to system performance. The ability to use performance assessment to show not only how the repository system is expected to perform, but also how it achieves that performance, should contribute substantially towards providing needed transparency to the safety case for a geologic repository. It is also a valuable tool during the development of the repository design and associated safety case, by identifying areas in which performance would be enhanced by increased redundancy
10 CFR 60.112 - Overall system performance objective for the geologic repository after permanent closure.

Science.gov (United States)

2010-01-01

... repository after permanent closure. 60.112 Section 60.112 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTES IN GEOLOGIC REPOSITORIES Technical Criteria Performance... environment following permanent closure conform to such generally applicable environmental standards for...

Review of Quality Assurance in SKB's Repository Research Experiments

International Nuclear Information System (INIS)

Hicks, T.W.

2007-01-01

SKB is preparing licence applications for a spent nuclear fuel encapsulation plant and repository which will be supported by the SR-Site safety report. A separate safety report, SR-Can, has been produced by SKB in preparation for the SR-Site report. SKI is in the process of reviewing the SR-Can safety report. In preparation for this review, and with a view to building confidence in SKB's research activities and understanding SKB's handling of data and other information, SKI has examined SKB's application of QA measures in the management and conduct of repository research and development projects that support the SR-Can safety assessment. These preliminary investigations will serve to support the preparation of more detailed quality and technical audits of SKB's repository safety assessment after the submission of a licence application. SKI's approach to this QA review is based on the consideration of quality-affecting aspects of a selection of SKB's research and development activities. As part of this review, SKI identified the need to examine quality-related aspects of some of the many experiments and investigations that form part of SKB's repository research programme. This report presents the findings of such a review, focusing on experiments concerned with the properties and performance of the engineered barrier system. First, in order to establish a broad understanding of QA requirements for repository scientific investigations, QA procedures implemented in the management of research and development activities for the low-level radioactive waste repository near Drigg in the UK and the Waste Isolation Pilot Plant and Yucca Mountain repository projects in the US were studied. The QA procedures for experiments and tests undertaken in these projects were compared with those implemented by SKB. Key findings are: QA programmes have been implemented for each repository development programme in response to regulatory requirements. The need for regular audits of the
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.
Waste package/engineered barrier system design concepts for the direct disposal of spent fuel in the potential United States' repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Stahl, D.; Harrison, D.J.

1993-01-01

The goal of the US Department of Energy's (DOE) Yucca Mountain Site Characterization Project (YMP) waste package development program is to design a waste package and associated engineered barrier system (EBS) that meets the applicable regulatory requirements for safe disposal of spent nuclear fuel and solidified high-level waste (HLW) in a geologic repository. Attainment of this goal relies on a multi-barrier approach, the unsaturated nature of the Yucca Mountain site, consideration of technical alternatives, and sufficient resolution of technical and regulatory uncertainties. To accomplish this, an iterative system engineering approach will be used. The NWPA of 1982 limits the content of the first US repository to 70,000 metric tons of heavy metal (MTHM). The DOE Mission Plan describes the implementation of the provisions of the NWPA for the waste management system. The Draft 1988 approach will involve selecting candidate designs, evaluating them against performance requirements, and then selecting one or two preferred designs for further detailed evaluation and final design. The reference design of the waste package described in the YMP Site Characterization Plan is a thin-walled, vertical borehole-emplaced waste package with an air gap between the package and the rock wall. The reference design appeared to meet the design requirement. However, the degree of uncertainty was large. This uncertainty led to considering several more-robust design concepts during the Advanced Conceptual Design phase of the program that include small, drift-emplaced packages and higher capacity, drift-emplaced packages, both partially and totally self-shielded. Metallic as well as ceramic materials are being considered
Phases, phase equilibria, and phase rules in low-dimensional systems

International Nuclear Information System (INIS)

Frolov, T.; Mishin, Y.

2015-01-01

We present a unified approach to thermodynamic description of one, two, and three dimensional phases and phase transformations among them. The approach is based on a rigorous definition of a phase applicable to thermodynamic systems of any dimensionality. Within this approach, the same thermodynamic formalism can be applied for the description of phase transformations in bulk systems, interfaces, and line defects separating interface phases. For both lines and interfaces, we rigorously derive an adsorption equation, the phase coexistence equations, and other thermodynamic relations expressed in terms of generalized line and interface excess quantities. As a generalization of the Gibbs phase rule for bulk phases, we derive phase rules for lines and interfaces and predict the maximum number of phases than may coexist in systems of the respective dimensionality
A Deterministic Safety Assessment of a Pyro-processed Waste Repository

International Nuclear Information System (INIS)

Lee, Youn Myoung; Jeong, Jong Tae; Choi, Jong Won

2012-01-01

A GoldSim template program for a safety assessment of a hybrid-typed repository system, called 'A-KRS', in which two kinds of pyro-processed radioactive wastes, low-level metal wastes and ceramic high-level wastes that arise from the pyro-processing of PWR nuclear spent fuels are disposed of, has been developed. This program is ready both for a deterministic and probabilistic total system performance assessment which is able to evaluate nuclide release from the repository and farther transport into the geosphere and biosphere under various normal, disruptive natural and manmade events, and scenarios. The A-KRS has been deterministically assessed with 5 various normal and abnormal scenarios associated with nuclide release and transport in and around the repository. Dose exposure rates to the farming exposure group have been evaluated in accordance with all the scenarios and then compared among other.
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.)
Status of the safety concept and safety demonstration for an HLW repository in salt. Summary report

Energy Technology Data Exchange (ETDEWEB)

Bollingerfehr, W.; Buhmann, D.; Filbert, W.; and others

2013-12-15

Salt formations have been the preferred option as host rocks for the disposal of high level radioactive waste in Germany for more than 40 years. During this period comprehensive geological investigations have been carried out together with a broad spectrum of concept and safety related R and D work. The behaviour of an HLW repository in salt formations, particularly in salt domes, has been analysed in terms of assessment of the total system performance. This was first carried out for concepts of generic waste repositories in salt and, since 1998, for a repository concept with specific boundary conditions, taking the geology of the Gorleben salt dome as an example. Suitable repository concepts and designs were developed, the technical feasibility has been proven and operational and long-term safety evaluated. Numerical modelling is an important input into the development of a comprehensive safety case for a waste repository. Significant progress in the development of numerical tools and their application for long-term safety assessment has been made in the last two decades. An integrated approach has been used in which the repository concept and relevant scientific and engineering data are combined with the results from iterative safety assessments to increase the clarity and the traceability of the evaluation. A safety concept that takes full credit of the favourable properties of salt formations was developed in the course of the R and D project ISIBEL, which started in 2005. This concept is based on the safe containment of radioactive waste in a specific part of the host rock formation, termed the containment providing rock zone, which comprises the geological barrier, the geotechnical barriers and the compacted backfill. The future evolution of the repository system will be analysed using a catalogue of Features, Events and Processes (FEP), scenario development and numerical analysis, all of which are adapted to suit the safety concept. Key elements of the
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...
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
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.
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)
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)
Distributed Repositories for Educational Content - Part 2: Technology

Directory of Open Access Journals (Sweden)

Christian Lukaschik

2011-07-01

Full Text Available In Part 1 of this article we discussed the need for information quality and the systematic management of learning materials and learning arrangements. Digital repositories, often called Learning Object Repositories (LOR, were introduced as a promising answer to this challenge. We also derived technological and pedagogical requirements for LORs from a concretization of information quality criteria for e-learning technology. This second part presents technical solutions that particularly address the demands of open education movements, which aspire to a global reuse and sharing culture. From this viewpoint, we develop core requirements for scalable network architectures for educational content management. We then present edu-sharing, an advanced example of a network of homogeneous repositories for learning resources, and discuss related technology. We conclude with an outlook in terms of emerging developments towards open and networked system architectures in e-learning.
Waste Package and Material Testing for the Proposed Yucca Mountain High Level Waste Repository

International Nuclear Information System (INIS)

Doering, Thomas; Pasupathi, V.

2002-01-01

Over the repository lifetime, the waste package containment barriers will perform various functions that will change with time. During the operational period, the barriers will function as vessels for handling, emplacement, and waste retrieval (if necessary). During the years following repository closure, the containment barriers will be relied upon to provide substantially complete containment, through 10,000 years and beyond. Following the substantially complete containment phase, the barriers and the waste package internal structures help minimize release of radionuclides by aqueous- and gaseous-phase transport. These requirements have lead to a defense-in-depth design philosophy. A multi-barrier design will result in a lower breach rate distributed over a longer period of time, thereby ensuring the regulatory requirements are met. The design of the Engineered Barrier System (EBS) has evolved. The initial waste package design was a thin walled package, 3/8 inch of stainless steel 304, that had very limited capacity, (3 PWR and 4 BWR assemblies) and performance characteristics, 300 to 1,000 years. This design required over 35,000 waste packages compared to today's design of just over 10,000 waste packages. The waste package designs are now based on a defense-in-depth/multi-barrier philosophy and have a capacity similar to the standard storage and rail transported spent nuclear fuel casks. Concurrent with the development of the design of the waste packages, a comprehensive waste package materials testing program has been undertaken to support the selection of containment barrier materials and to develop predictive models for the long-term behavior of these materials under expected repository conditions. The testing program includes both long-term and short-term tests and the results from these tests combination with the data published in the open literature are being used to develop models for predicting performance of the waste packages
Analysis of the processes defining radionuclide migration from deep geological repositories in porous medium

International Nuclear Information System (INIS)

Brazauskaite, A.; Poskas, P.

2004-01-01

Due to the danger of exposure arising from long-lived radionuclides to humans and environment, spent nuclear fuel (SNF) and high level waste (HLW) are not allowed to be disposed of in near surface repositories. There exists an international consensus that such high level and long-lived radioactive wastes are best disposed of in geological repositories using a system of engineered and natural barriers. At present, the geological repository of SNF and HLW has not been realized yet in any country but there is a lot of experience in the assessment of radionuclide migration from deep repositories, investigations of different processes related to the safety of a disposal system. The aim of this study was to analyze the processes related to the radionuclide migration from deep geological repositories in porous medium such as SNF matrix dissolution, release mechanism of radionuclides from SNF matrix, radionuclide solubility, sorption, diffusive, advective transport of radionuclides from the canister and through the engineered and natural barriers. It has been indicated that SNF matrix dissolution, radionuclide solubility and sorption are sensitive to ambient conditions prevailing in the repository. The approaches that could be used for modeling the radionuclide migration from deep repositories in porous medium are also presented. (author)
SAPIERR Paves the way towards European regional repository

International Nuclear Information System (INIS)

Stefula, V.; McCombie, C.

2004-01-01

development to be carried out in future. High profile will be given to so-called co-operative scenario, which is most appropriate for the European context. The identification of the potential host country was deliberately excluded from the scope of SAPIERR project in this first phase. The working group participants will correspond throughout the two year duration of the study and will meet again towards the end of the project at an international seminar in Brussels in October 2005. The objective of the seminar will be to review and disseminate results of the project to a wide audience and to agree on subsequent steps on the way towards the European Regional Repository.(author)
Development of site selection process for an LILW repository in Slovenia

International Nuclear Information System (INIS)

Zeleznik, N.; Kralj, M.; Mele, I.; Veselic, M.

2005-01-01

The activities regarding the LILW repository site selection in Slovenia are planned to meet the requirements of the Act on Ionising Radiation Protection and Nuclear Safety, especially the requirement that the site for a repository should be selected by 2008 and the repository should be in operation by 2013. In November 2004, the official administrative procedure for the siting of the repository started with the first spatial public conference on spatial planning procedure. It was carried out by the Ministry of the Environment and Spatial Planning and ARAO. Immediately after the conference the Program for the preparation of the detailed plan of national importance for the LILW repository was accepted by the Ministry. At the beginning of December 2004, ARAO invited all Slovenian local communities to participate in the site selection process and volunteer a site or area in their local community for further investigation. At the beginning of April 2005 the first phase of the bidding process was concluded. ARAO received applications from eight local communities. A pre-feasibility study to define three of the most promising locations was conducted because only three locations are foreseen by the Program for the preparation of the detailed plan of national importance. Methodologies were prepared for assessment of different parameters of technical, financial, environmental and spatial suitability as well as public acceptability. Comparative, preferential and also exclusion criteria for the respective parameters were defined. The results of the cabinet and fieldwork research were compared and further assessed in order to obtain maximum three local communities with three potential sites in which the probability of siting the LILW repository seems to be the highest. Detailed plans of national importance will be prepared for these sites. (author)
Morsleben repository - Interdependence of technical feasibility and functionality of geotechnical barriers and safety case development

International Nuclear Information System (INIS)

Wollrath, Juergen; Mauke, Ralf; Mohlfeld, Matthias; Niemeyer, Matthias; Becker, Dirk-Alexander

2014-01-01

Based on a selection procedure whereby ten existing mines had been taken into consideration, the Morsleben repository for radioactive waste (ERAM) was built in a former mine for potash and rock salt production. The specific concerns and objectives of a repository for radioactive waste could not be taken into account when the mine was built at the beginning of the last century. Irrespective of this, altogether about 37 000 m 3 of low-level and intermediate-level radioactive waste was stored in several areas of the mine between 1971 and 1991 and from 1994 to 1998. In the scope of the ongoing licensing procedure, the safety of the 'historically grown' repository needs to be demonstrated for the phase after it has been sealed. (authors)
Proposed format and content of environmental reports for deep geologic terminal repositories for radioactive material

International Nuclear Information System (INIS)

Carrell, D.J.; Jones, G.L.

1978-01-01

As the Nuclear Regulatory Commission has not yet issued a format guide for the preparation of an environmental impact statement for radioactive waste repositories, Rockwell Hanford operations has developed an annotated outline which will serve as the basis for the environmental evaluation activities until replaced by an appropriate NRC regulatory guide. According to the outline, the applicant should summarize the major environmental effects that are expected to occur during the construction, operation, and terminal isolation phases of the radioactive material repository. Compare these environmental effects with the possible effect of continued use of interim storage facilities. Unless unforeseen environmental effects become apparent, the summary should be a positive statement indicating that the short-term environmental effects are outweighed by the long-term benefits of the repository
Reactive transport predictions for an Olkiluoto. Final repository tunnel unit

International Nuclear Information System (INIS)

Luukkonen, A.; Nordman, H.

2007-09-01

The presented hydrogeochemical reactive transport calculations concentrate to a defined unit piece (unit cell) of the planned Olkiluoto repository that is under design for spent nuclear fuel. The material properties assigned to the tunnel unit are based on literature as far as possible. Calculations make up geochemical future scenarios on the repository evolution. Most recent predictions on the potential future climate at Olkiluoto are utilised together with estimates how future hydraulic conditions affect the repository. Two climate scenarios are considered in detail. The Weichselian-R scenario is based on the repetition of the last glacial cycle, while the Emissions-M scenario attempts to predict the future groundwater conditions at Olkiluoto in the situation where the atmospheric greenhouse gasses delay the next glacial cycle at least for 100,000 years. The groundwater compositions, considered active at the repository depth in future, are judged in this study. Several geochemical processes are considered active at the repository depth. Calculations concentrate on the changes occurring with time within the tunnel unit. All simulations are done in geochemically reducing conditions. It turns out that sulphur cycling in these conditions is in central role considering the safety assessment studies of Olkiluoto repository. Furthermore, groundwater salinity and cation occupancy within the exchange sites of montmorillonite contributes to sealing properties of the engineered barrier system. Calculations attempt to estimate effects of possible future scenarios for the Olkiluoto repository. The results indicate that the buffer capacities assigned to the tunnel unit are large enough, at least to next 100,000 years, to maintain dissolved sulphide contents low in the groundwater infiltrating through the tunnel engineered barrier system. Geochemical reactions raise the bicarbonate levels within the groundwater. This is a useful buffer if low pH conditions emerge in the

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)
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)
Embracing the Future: Embedding Digital Repositories in Higher Education Institutions. Research Brief

Science.gov (United States)

Hoorens, Stijn; van Dijk, Lidia Villalba; van Stolk, Christian

2009-01-01

This briefing paper captures the key findings and recommendations of a study commissioned by the Joint Information Systems Committee on aspects of the strategic commitment of institutions to repository sustainability. This project, labelled EMBRACE (EMBedding Repositories And Consortial Enhancement), is aimed at enhancing the functionality,…
Czech Republic. Dukovany repository

International Nuclear Information System (INIS)

2001-01-01

Full text: The repository at the Dukovany site is a structure located above the land surface. It consists of two double-rows of reinforced concrete vaults. Each double-row has dimensions 38x160x6 meters and contains 2x28 vaults. The internal dimensions of each vault are 18x6x5.4 meters. The repository serves for reactor wastes from the Dukovany and Temelin nuclear power plants (NPPs). Its capacity is 55,000 m 3 or 130,000 drums. The repository is a fully engineered facility with multiple barriers. The first engineered barrier is the waste form (in the case of waste from the Dukovany NPP, the waste form is mainly bitumen, but concrete and glass are also considered as suitable solidification products). The second barrier is the container (a 200 litre steel drum or a HIC container), whereas the third consists of cut-off reinforced concrete walls with asphalt-based hydro-insulation. The fourth barrier is a cap which should protect the vaults against infiltration of rainwater and should serve also as an intrusion and erosion barrier. The fifth barrier is a drainage system around the repository which is composed of layers of gravel and sand. The void space in drums around the waste is filled with specially composed grout. Such waste packages are emplaced into the disposal vault, which is covered by pre-fabricated panels. Thereafter, joints between the panels are sealed and a provisional coverage added; the final cover, however, will be constructed only over the whole row of 28 vaults, until all vaults are filled with waste. The final cover will encompass the following components: reinforced concrete pre-fabricated panels (500 mm); cement overcoat (30 mm); insulation foil; concrete layer for cap levelling (5-150 mm); layer of asphalto-propylene concrete (150 mm); soil (450 mm); geotextile foil with topsoil (top surface vegetation). (author)
A study of uranium and thorium migration at the Koongarra uranium deposit with application to actinide transport from nuclear waste repositories

International Nuclear Information System (INIS)

Payne, T.E.

1991-01-01

One way to gain confidence in modelling possible radionuclide releases is to study natural systems which are similar to components of the multibarrier waste repository. Several such analogues are currently under study and these provide useful data about radionuclide behaviour in the natural environment. One such system is the Koongarra uranium deposit in the Northern Territory. In this dissertation, the migration of actinides, primarily uranium and thorium, has been studied as an analogue for the behaviour of transuranics in the far-field of a waste repository. The major findings of this study are: 1. the main process retarding uranium migration in the dispersion fan at Koongarra is sorption, which suppresses dissolved uranium concentrations well below solubility limits, with ferrihydrite being a major sorbing phase; 2. thorium is extremely immobile, with very low dissolved concentrations and corresponding high distribution ratios for 230 Th. Overall, it is estimated that colloids are relatively unimportant in Koongarra groundwater. Uranium migrates mostly as dissolved species, whereas thorium and actinium are mostly adsorbed to larger, relatively immobile particles and the stationary phase. However, of the small amount of 230 Th that passes through a 1μm filter, a significant proportion is associated with colloidal particles. Actinium appears to be slightly more mobile than thorium and is associated with colloids to a greater extent, although generally present in low concentrations. These results support the possibility of colloidal transport of trivalent and tetravalent actinides in the vicinity of a nuclear waste repository. 112 refs., 23 tabs., 32 figs
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
Implementing adaptive phased management (APM) for Canada's used nuclear fuel

International Nuclear Information System (INIS)

King, F.

2008-01-01

This paper discusses the implementation of Adaptive Phased Management (APM) for Canada's used nuclear fuel. APM is a combination of technology and management system. The technology involves centralized containment and isolation in deep geological repository in a suitable rock formation, as well as shallow storage where used fuel remains retrievable. In both cases there is continuous monitoring. The management system consists of public engagement, phased decision-making, continuous learning and adaption, open and inclusive. Finally, it involves seeking an in formed willing host community
The Swedish approach to siting of a deep geological repository and interaction with the public

International Nuclear Information System (INIS)

Thegerstroem, C.

1993-01-01

The planned process for siting of a deep geological repository for encapsulated spent nuclear fuel in Sweden was presented in the 1992 SKB R and D programme. A first phase of the repository operation will be limited to disposal of a small amount of encapsulated spent nuclear fuel (approximately 800 tons). This phase will be followed by an evaluation of experiences as well as alternative options before deciding if, when and how to proceed with disposal of the remaining amounts of spent fuel. During the first phase it will be possible to retrieve the waste. Siting is planned to be done in stages. The field studies and safety assessments performed strongly indicate that it is possible to find geological suitable sites within many regions of Sweden. The potential for fulfilling safety requirements will be a crucial factor in site-selection. Local interest in, and attitude to a repository siting will play an important role in the siting process. It is important that an atmosphere of trust and openness can be established. Extensive geological site characterization work will be carried out at the sites selected and studies of other technical, social, economical or political matters will be equally important. Public communication and local participation will form an essential part of the siting programme from the outset. 3 refs., 3 figs
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
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
STAFAN, Fluid Flow, Mechanical Stress in Fractured Rock of Nuclear Waste Repository

International Nuclear Information System (INIS)

Huyakorn, P.; Golis, M.J.

1989-01-01

1 - Description of program or function: STAFAN (Stress And Flow Analysis) is a two-dimensional, finite-element code designed to model fluid flow and the interaction of fluid pressure and mechanical stresses in a fractured rock surrounding a nuclear waste repository. STAFAN considers flow behavior of a deformable fractured system with fracture-porous matrix interactions, the coupling effects of fluid pressure and mechanical stresses in a medium containing discrete joints, and the inelastic response of the individual joints of the rock mass subject to the combined fluid pressure and mechanical loading. 2 - Restrictions on the complexity of the problem: STAFAN does not presently contain thermal coupling, and it is unable to simulate inelastic deformation of the rock mass and variably saturated or two-phase flow in the fractured porous medium system
Physico-chemical interactions at the concrete-bitumen interface of nuclear waste repositories

Directory of Open Access Journals (Sweden)

Sablayrolles C.

2013-07-01

Full Text Available This study investigates the fate of nitrate and organic acids at the bitumenconcrete-steel interface within a repository storage cell for long-lived, intermediatelevel, radioactive wastes. The interface was simulated by a multiphase system in which cementitious matrices (CEM V-paste specimens were exposed to bitumen model leachates consisting of nitrates and acetic acid with and without oxalic acid, chemical compounds likely to be released by bitumen. Leaching experiments were conducted with daily renewal of the solutions in order to accelerate reactions. C-steel chips, simulating the presence of steel in the repository, were added in the systems for some experiments. The concentrations of anions (acetate, oxalate, nitrate, and nitrite and cations (calcium, potassium, ammonium and the pH were monitored over time. Mineralogical changes of the cementitious matrices were analysed by XRD. The results confirmed the stability of nitrates in the absence of steel, whereas, reduction of nitrates was observed in the presence of steel (production of NH4+. The action of acetic acid on the cementitious matrix was similar to that of ordinary leaching; no specific interaction was detected between acetate and cementitious cations. The reaction of oxalic acid with the cementitious phases led to the precipitation of calcium oxalate salts in the outer layer of the matrix. The concentration of oxalate was reduced by 65% inside the leaching medium.
Physico-chemical interactions at the concrete-bitumen interface of nuclear waste repositories

Science.gov (United States)

Bertron, A.; Ranaivomanana, H.; Jacquemet, N.; Erable, B.; Sablayrolles, C.; Escadeillas, G.; Albrecht, A.

2013-07-01

This study investigates the fate of nitrate and organic acids at the bitumenconcrete-steel interface within a repository storage cell for long-lived, intermediatelevel, radioactive wastes. The interface was simulated by a multiphase system in which cementitious matrices (CEM V-paste specimens) were exposed to bitumen model leachates consisting of nitrates and acetic acid with and without oxalic acid, chemical compounds likely to be released by bitumen. Leaching experiments were conducted with daily renewal of the solutions in order to accelerate reactions. C-steel chips, simulating the presence of steel in the repository, were added in the systems for some experiments. The concentrations of anions (acetate, oxalate, nitrate, and nitrite) and cations (calcium, potassium, ammonium) and the pH were monitored over time. Mineralogical changes of the cementitious matrices were analysed by XRD. The results confirmed the stability of nitrates in the absence of steel, whereas, reduction of nitrates was observed in the presence of steel (production of NH4+). The action of acetic acid on the cementitious matrix was similar to that of ordinary leaching; no specific interaction was detected between acetate and cementitious cations. The reaction of oxalic acid with the cementitious phases led to the precipitation of calcium oxalate salts in the outer layer of the matrix. The concentration of oxalate was reduced by 65% inside the leaching medium.
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
Annotated outline for the SCP conceptual design report: Office of Geologic Repositories

International Nuclear Information System (INIS)

1987-06-01

The Nuclear Waste Policy Act of 1982 (NWPA) requires that site characterization plans (SCPs) be submitted to the Nuclear Regulatory Commission (NRC), affected States and Indian tribes, and the general public for review and comment prior to the sinking of shafts at a candidate repository site. The SCP is also required by the NRC licensing procedures for the disposal of high-level waste. An Annotated Outline (AO) for Site Characterization Plans (OGR/B-5) has been prepared to provide DOE's standard format and guidance for preparation of SCPs. Consistent with the AO for SCPs. Chapter 6 of the SCP is to provide the requirements and references the media-specific design data base, describe the current design concepts, and discuss design information needs. In order to develop this design information, the Office of Geologic Repositories program is planning a SCP conceptual design phase as part of the overall repository design process. This phase is the first step in the design process, and the result and design can be expected to change as the program moves through the site characterization phase. The Annotated Outline which follows provides the standard format and guidance for the preparation of the SCP Conceptual Design Reports. It is considered to meet the intent of NRC's proposed Generic Technical Position philosophy contained therein. The SCP Conceptual Design Report will be the primary basis for preparation of Chapter 6 of the SCP and will be stand-alone reference document for the SCP. Appendix 1 to this Annotated Outline provides a correlation between Chapter 6 of the SCP and SCP Conceptual Design Report for the information purposes
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

The calculated post-closure performance of a radioactive waste repository is generally quantified in terms of radiological dose or risk to humans, with safety being determined by whether the calculated exposure values are consistent with predetermined target criteria which are deemed to represent acceptable radiological hazards. Despite their general acceptance, however, dose and risk are not perfect measures of repository safety because, in order to calculate them, gross assumptions must be made for future human behaviour patterns. Such predictions clearly become increasingly uncertain as forecasts are made further into the future. As a consequence, there has been a growing interest in developing other ways of assessing repository safety which do not require assumptions to be made for future human behaviour. One proposed assessment method is to use the distributions of naturally-occurring chemical species in the environment, expressed either as concentrations or fluxes of elements, radionuclides or radioactivity, as natural safety indicators which may be compared with the PA predictions of repository releases. Numerous comparisons are possible between the repository and natural systems. The primary objective is to use the natural system to provide context to the hazard presented by the repository releases. Put simply, if it can be demonstrated that the flux to the biosphere from the repository is not significant compared with the natural flux from the geosphere, then its radiological significance should not be of great or priority concern. Natural safety indicators may be quantified on a site specific basis, using information derived from a repository site characterisation programme, and can be compared to the outputs from the associated site specific PAs. Such calculations and comparisons may be very detailed and might examine, for example, the spatial and temporal variations in the distributions and fluxes of naturally-occurring chemical species arising from
ETD Management and Publishing in the ProQuest System and the University Repository: A Comparative Analysis

Directory of Open Access Journals (Sweden)

Gail P. Clement

2013-08-01

Full Text Available INTRODUCTION This study compares the two most popular ETD management and publishing systems used in the American higher education community today: the commercial ProQuest Dissertation Publishing system and the university repository. METHODS Characteristics of these systems are identified and categorized in order to determine the features, functions, and policies common to both, and those that uniquely characterize one or the other system. Performing such a head-to-head comparison provides valuable information and insights to decision makers responsible for managing or overhauling their university’s ETD program. RESULTS Comparison of characteristics shows the ProQuest system and the university repository both provide functional solutions for submitting, storing, disseminating, and archive ETDs using digital technology. Yet each system also has unique characteristics that distinguish it from the other. DISCUSSION & CONCLUSION The authors conclude that there is no single ‘best’ system for ETD management overall. Rather, it is up to decision makers at each institution to choose an approach that best fits their university’s values, goals and needs. Finally, the authors point out the need for a single portal for ETDs that allows for search and discovery of these unique works of scholarship wherever the full text resides. Future investigation into possible solutions for such an ETD portal would be a boon not only to universities and ETD authors, but to the broader community of researchers, students, professionals and interested citizenry who could benefit from easier access to this this growing corpus of knowledge.
A Generic Water Balance Model for a Trench Repository

International Nuclear Information System (INIS)

Lee, Youn Myoung; Choi, Hee Joo

2016-01-01

To quantify the exposure dose rates from the nuclide release and transport through the various pathways possible in the near- and far-fields of the LILW repository system, various scenarios are to be conveniently simulated in a straightforward manner and extensively with this GoldSim model, as similarly developed for other various types of repositories in previous studies. Through this study, a result from four scenario cases, each of which is or is not associated with water balance, are compared to each other to see what happens in different cases in which an overflow over a trench rooftop, stochastic rainfall on the trench cover, and an unsaturated flow scheme under the trench bottom are combined. The other two latter elements vary periodically owing to stochastic behavior of the time series data for the past rain-fall records. This program is ready for a total system performance assessment and is able to deterministically and probabilistically evaluate the nuclide release from a repository and farther transport into the geosphere and biosphere under various scenarios that can occur after a failure of waste packages with associated uncertainty. An illustration conducted through a study with a new water balance scheme shows the possibility of a stochastic evaluation associated with the stochastic behavior and various pathways that happen around the trench repository.
A Generic Water Balance Model for a Trench Repository

Energy Technology Data Exchange (ETDEWEB)

Lee, Youn Myoung; Choi, Hee Joo [KAERI, Daejeon (Korea, Republic of)

2016-05-15

To quantify the exposure dose rates from the nuclide release and transport through the various pathways possible in the near- and far-fields of the LILW repository system, various scenarios are to be conveniently simulated in a straightforward manner and extensively with this GoldSim model, as similarly developed for other various types of repositories in previous studies. Through this study, a result from four scenario cases, each of which is or is not associated with water balance, are compared to each other to see what happens in different cases in which an overflow over a trench rooftop, stochastic rainfall on the trench cover, and an unsaturated flow scheme under the trench bottom are combined. The other two latter elements vary periodically owing to stochastic behavior of the time series data for the past rain-fall records. This program is ready for a total system performance assessment and is able to deterministically and probabilistically evaluate the nuclide release from a repository and farther transport into the geosphere and biosphere under various scenarios that can occur after a failure of waste packages with associated uncertainty. An illustration conducted through a study with a new water balance scheme shows the possibility of a stochastic evaluation associated with the stochastic behavior and various pathways that happen around the trench repository.
Siting guidelines and their role in repository site selection

International Nuclear Information System (INIS)

Hanlon, C.L.

1985-01-01

The first requirement of the Nuclear Waste Policy Act was for the Secretary of Energy to issue general guidelines for siting repositories. The guidelines were to specify detailed geologic considerations that would be the primary criteria for the selection of sites in various host rocks, as well as factors that would qualify or disqualify any site from development as a repository. These guidelines were clearly intended to provide not only the framework for the siting program but also the stimulus for establishing effective communication and consultation among the parties involved in the program. The Act further required that the guidelines be a factor in the development of all future decision documents of the Office of Civilian Radioactive Waste Management, including the environmental assessments that would accompany the nomination of sites for characterization, the site-characterization plans that are to be prepared before the sinking of exploratory shafts at any candidate site, and the environmental impact statement that is to support the recommendation of a site for development as a repository. More than two years after its passage, the intention of the Act for the guidelines has been realized. Concurred in by the Nuclear Regulatory Commission on June 22, 1984, and issued by the Department in November 1984, the guidelines include postclosure technical guidelines that apply to conditions governing the long-term performance of the repository system; preclosure technical guidelines that apply to conditions governing the siting, construction, operation, and closure of the repository; and system guidelines whose objective is to ensure that the regulatory requirements of the Environmental Protection Agency and the Nuclear Regulatory Commission are met

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.
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)
Experimental investigation of hydrous pyrolysis of diesel fuel and the effect of pyrolysis products on performance of the candidate nuclear waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Jackson, K.J.; Carroll, S.A.

1994-01-01

It is thought that a significant amount of diesel fuel and other hydrocarbon-rich phases may remain inside the candidate nuclear waste repository at Yucca Mountain after construction and subsequent emplacement of radioactive waste. Although the proposed repository horizon is above the water table, the remnant hydrocarbon phases may react with hydrothermal solutions generated by high temperature conditions that will prevail for a period of time in the repository. The preliminary experimental results of this study show that diesel fuel hydrous pyrolysis is minimal at 200 degrees C and 70 bars. The composition of the diesel fuel remained constant throughout the experiment and the concentration of carboxylic acids in the aqueous phases was only slightly above the detection limit (1-2 ppm) of the analytical technique
Long-Term Safety Analysis of Baldone Radioactive Waste Repository and Updating of Waste Acceptance Criteria

International Nuclear Information System (INIS)

2001-12-01

The main objective of the project was to provide advice to the Latvian authorities on the safety enhancements and waste acceptance criteria for near surface radioactive waste disposal facilities of the Baldone repository. The project included the following main activities: Analysis of the current status of the management of radioactive waste in Latvia in general and, at the Baldone repository in particular Development of the short and long-term safety analysis of the Baldone repository, including: the planned increasing of capacity for disposal and long term storage, the radiological analysis for the post-closure period Development of the Environment Impact Statement, for the new foreseen installations, considering the non radiological components Proposal of recommendations for future updating of radioactive waste acceptance criteria Proposal of recommendations for safety upgrades to the facility. The work programme has been developed in phases and main tasks as follows. Phase 0: Project inception, Phase 1: Establishment of current status, plans and practices (Legislation, regulation and standards, Radioactive waste management, Waste acceptance criteria), Phase 2: Development of future strategies for long-term safety management and recommendations for safety enhancements. The project team found the general approach use at the installation, the basic design and the operating practices appropriate to international standards. Nevertheless, a number of items subject to potential improvements were also identified. These upgrading recommendations deal with general aspects of the management (mainly storage versus disposal of long-lived sources), site and environmental surveillance, packaging (qualification of containers, waste characterization requirements), the design of an engineered cap and strategies for capping. (author)
Audit and Certification Process for Science Data Digital Repositories

Science.gov (United States)

Hughes, J. S.; Giaretta, D.; Ambacher, B.; Ashley, K.; Conrad, M.; Downs, R. R.; Garrett, J.; Guercio, M.; Lambert, S.; Longstreth, T.; Sawyer, D. M.; Sierman, B.; Tibbo, H.; Waltz, M.

2011-12-01

Science data digital repositories are entrusted to ensure that a science community's data are available and useful to users both today and in the future. Part of the challenge in meeting this responsibility is identifying the standards, policies and procedures required to accomplish effective data preservation. Subsequently a repository should be evaluated on whether or not they are effective in their data preservation efforts. This poster will outline the process by which digital repositories are being formally evaluated in terms of their ability to preserve the digitally encoded information with which they have been entrusted. The ISO standards on which this is based will be identified and the relationship of these standards to the Open Archive Information System (OAIS) reference model will be shown. Six test audits have been conducted with three repositories in Europe and three in the USA. Some of the major lessons learned from these test audits will be briefly described. An assessment of the possible impact of this type of audit and certification on the practice of preserving digital information will also be provided.
The industrial organization of the repository. Pitfall or logical?; Slutfoervarets industriella organisering. Fallgrop eller foeljdriktighet?

Energy Technology Data Exchange (ETDEWEB)

Frostenson, Magnus (Dept. of Business Studies, Uppsala Univ., Uppsala (Sweden))

2010-11-15

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
A scoping review of online repositories of quality improvement projects, interventions and initiatives in healthcare.

Science.gov (United States)

Bytautas, Jessica P; Gheihman, Galina; Dobrow, Mark J

2017-04-01

Quality improvement (QI) is becoming an important focal point for health systems. There is increasing interest among health system stakeholders to learn from and share experiences on the use of QI methods and approaches in their work. Yet there are few easily accessible, online repositories dedicated to documenting QI activity. We conducted a scoping review of publicly available, web-based QI repositories to (i) identify current approaches to sharing information on QI practices; (ii) categorise these approaches based on hosting, scope and size, content acquisition and eligibility, content format and search, and evaluation and engagement characteristics; and (iii) review evaluations of the design, usefulness and impact of their online QI practice repositories. The search strategy consisted of traditional database and grey literature searches, as well as expert consultation, with the ultimate aim of identifying and describing QI repositories of practices undertaken in a healthcare context. We identified 13 QI repositories and found substantial variation across the five categories. The QI repositories used different terminology (eg, practices vs case studies) and approaches to content acquisition, and varied in terms of primary areas of focus. All provided some means for organising content according to categories or themes and most provided at least rudimentary keyword search functionality. Notably, none of the QI repositories included evaluations of their impact. With growing interest in sharing and spreading best practices and increasing reliance on QI as a key contributor to health system performance, the role of QI repositories is likely to expand. Designing future QI repositories based on knowledge of the range and type of features available is an important starting point for improving their usefulness and impact. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
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.
The Stability of Magnetite and its Significance as a Passivating Film in the Repository Environment

International Nuclear Information System (INIS)

Hermansson, Hans-Peter

2004-01-01

A literature review was made in order to highlight if magnetite could be formed as a passivating film on iron in the expected repository environment. The possibility to form other types of passivating films has also been regarded, e.g. other iron oxides or mixed oxides of iron and copper and also sulfides. The conditions for the formation of different types of films have been discussed as well as their compositions and properties. It is concluded that magnetite could certainly be formed on iron at repository combinations of Eh and pH in the absence of sulphide and chloride. However, magnetite could easily be outnumbered by other solid phases that could be formed at the simultaneous presence of copper. CuFeO 2 is such a phase that could appear in a simple Fe-Cu-O-H system. As soon as sulphide and chloride are present other phases like CuFeS 2 could also be responsible for the passivation of iron. The probability that magnetite is the passivating film on cast iron at the actual conditions is therefore not very large. It is more likely that the passivating film instead consists of CuFeO 2 and/or CuFeS 2 , the latter depending on the concentration of sulphur in the system. The protective ability of the alternate compounds as passivating films could be discussed. A suggested ranking order of the protective ability is given in the discussion part. If magnetite is not stable, the integrity of the cast iron insert could therefore in such cases be dependent on the protection by less effective passivating substances. The hypothesis of the formation and nature of alternative passivating films should be tested at relevant conditions in laboratory experiments
A Nuclide Release Model for a Deep Well Scenario near a Repository

International Nuclear Information System (INIS)

Lee, Youn Myoung; Jung, Jong Tae; Choi, Jong Won

2010-01-01

Recently several template programs ready for the safety assessment of a high-level radioactive waste repository (HLW) and a low- and intermediate level radioactive waste repository (LILW) systems, that are conceptually modeled, have been developed by utilizing GoldSim and AMBER at KAERI. During the last few years, such template programs have been utilized for the evaluation of nuclide transports in the nearand far-field of a repository as well as transport through the biosphere under various normal and disruptive release scenarios with assumed data. The GoldSim program, another template program by which influence due to a well located very near to the repository has been modeled and evaluated for an assumed case in order to simulate the worst exposure scenario. This seems very useful to evaluate an accidental event a long time after closure of the repository has been developed and illustrated
Review. Deep repository for spent nuclear fuel SR 97 - Post-closure safety

Energy Technology Data Exchange (ETDEWEB)

Stephansson, Ove [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Civil and Environmental Engineering

2000-12-01

SKB states that the chosen scenarios provide good coverage of future evolutionary pathways for the deep repository. This is not the case. SKB has not made full use of the established interaction matrices and the new method of THMC diagrams to generate the relevant and important scenarios and to construct the important pathways of variables and processes, either in the established interaction matrices and the presented THMC diagrams. Hence, SKB is demonstrating in SR 97 that they lack a well thought through, sound and solid method to select and evaluate scenarios for the purpose of demonstrating the safety of a deep repository for spent nuclear fuel. The evolution of the system is presented for the components of the repository system (fuel, canister, buffer/backfill, geosphere) and the effects of four different scenarios, but time only enters into the system for discrete events or processes, e.g. description of the relative radiotoxicity and heat decay of the fuel, temperature distribution, iron exchange process, pH in buffer, redox capacity and radionuclear release at the three sites. There is a lack of method and way of describing the evolution of the complete repository system, including the major scenarios, as a function of time. It is essential that SKB is able to: - consider the full range of potential scenarios, - grade the scenarios according to their significance for repository design and performance and safety assessment, - consider whether simple engineering actions could be taken to inhibit the development of adverse scenarios. This cannot be done with the system presented in SR 97, and so SKB do not have a full predictive capability - which is required for the engineering design of such an important and costly structure as a repository. Geoscientific investigation material for three selected sites are presented by SKB in the technical report dealing with waste, repository design and sites. Here a general overview is missing of the geological and rock
Institutional Repositories, Open Access, and Scholarly Communication: A Study of Conflicting Paradigms

Science.gov (United States)

Cullen, Rowena; Chawner, Brenda

2011-01-01

The Open Access movement of the past decade, and institutional repositories developed by universities and academic libraries as a part of that movement, have openly challenged the traditional scholarly communication system. This article examines the growth of repositories around the world, and summarizes a growing body of evidence of the response…
Evaluation of radiological safety assessment of a repository in a clay rock formation

International Nuclear Information System (INIS)

1999-01-01

This report presents a comprehensive description of the post-closure radiological safety assessment of a repository for the spent fuel arisings resulting from the Spanish nuclear program excavated in a clay host rock formation. In this report three scenarios have been analysed in detail. The first scenario represents the normal in detail. The first scenario represents the normal evolution of the repository (Reference Scenario); and includes a set of variants to investigate the relative importance of the various repository components and examine the sensitivity of the performance to parameters variations. Two altered scenarios have also been considered: deep well construction and poor sealing of the repository. This document contains a detailed description of the repository system, the methodology adopted for the scenarios generation, the process modelling approach and the results of the consequences analysis. (Author)
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)
Object linking in repositories

Science.gov (United States)

Eichmann, David (Editor); Beck, Jon; Atkins, John; Bailey, Bill

1992-01-01

This topic is covered in three sections. The first section explores some of the architectural ramifications of extending the Eichmann/Atkins lattice-based classification scheme to encompass the assets of the full life cycle of software development. A model is considered that provides explicit links between objects in addition to the edges connecting classification vertices in the standard lattice. The second section gives a description of the efforts to implement the repository architecture using a commercially available object-oriented database management system. Some of the features of this implementation are described, and some of the next steps to be taken to produce a working prototype of the repository are pointed out. In the final section, it is argued that design and instantiation of reusable components have competing criteria (design-for-reuse strives for generality, design-with-reuse strives for specificity) and that providing mechanisms for each can be complementary rather than antagonistic. In particular, it is demonstrated how program slicing techniques can be applied to customization of reusable components.
Results from an International Simulation Study on Couples Thermal, Hydrological, and Mechanical (THM) Processes Near Geological Nuclear Waste Repositories

International Nuclear Information System (INIS)

J. Rutqvist; J.T. Birkholzer; M. Chijimatsu; O. Kolditz; Q.S. Liu; Y. Oda; W. Wang; C.Y. Zhang

2006-01-01

As part of the ongoing international code comparison project DECOVALEX, four research teams used five different models to simulate coupled thermal, hydrological, and mechanical (THM) processes near underground waste emplacement drifts. The simulations were conducted for two generic repository types with open or back-filled repository drifts under higher and lower post-closure temperature, respectively. In the completed first model inception phase of the project, a good agreement was achieved between the research teams in calculating THM responses for both repository types, although some disagreement in hydrological responses are currently being resolved. Good agreement in the basic thermal-mechanical responses was achieved for both repository types, even with some teams using relatively simplified thermal-elastic heat-conduction models that neglect complex near-field thermal-hydrological processes. The good agreement between the complex and simplified (and well-known) process models indicates that the basic thermal-mechanical responses can be predicted with a relatively high confidence level. The research teams have now moved on to the second phase of the project, the analysis of THM-induced permanent (irreversible) changes and the impact of those changes on the fluid flow field near an emplacement drift
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
Assessment of effectiveness of geologic isolation systems. Test case release consequence analysis for a spent fuel repository in bedded salt

International Nuclear Information System (INIS)

Raymond, J.R.; Bond, F.W.; Cole, C.R.; Nelson, R.W.; Reisenauer, A.E.; Washburn, J.F.; Norman, N.A.; Mote, P.A.; Segol, G.

1980-01-01

Geologic and geohydrologic data for the Paradox Basin have been used to simulate movement of ground water and radioacrtive contaminants from a hypothetical nuclear reactor spent fuel repository after an assumed accidental release. The pathlines, travel times and velocity of the ground water from the repository to the discharge locale (river) were determined after the disruptive event by use of a two-dimensional finite difference hydrologic model. The concentration of radioactive contaminants in the ground water was calculated along a series of flow tubes by use of a one-dimensional mass transport model which takes into account convection, dispersion, contaminant/media interactions and radioactive decay. For the hypothetical site location and specific parameters used in this demonstration, it is found that Iodine-129 (I-129) is tthe only isotope reaching the Colorado River in significant concentration. This concentration occurs about 8.0 x 10 5 years after the repository has been breached. This I-129 ground-water concentration is about 0.3 of the drinking water standard for uncontrolled use. The groundwater concentration would then be diluted by the Colorado River. None of the actinide elements reach more than half the distance from the repository to the Colorado River in the two-million year model run time. This exercise demonstrates that the WISAP model system is applicable for analysis of contaminant transport. The results presented in this report, however, are valid only for one particular set of parameters. A complete sensitivity analysis must be performed to evaluate the range of effects from the release of contaminants from a breached repository
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
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.

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
Geologic nuclear waste repository site selection studies in the Paradox Basin, Utah

International Nuclear Information System (INIS)

Rogers, T.H.; Conwell, F.R.

1981-01-01

During Phase I regional-level studies, a literature review was conducted to ascertain geologic characteristics pertinent to repository siting factors. On the basis of the regional screening results, four areas in southeastern Utah were selected as being suitable for more detailed study in Phase II: Elk Ridge and Gibson Dome, containing nearly horizontal bedded salt deposits; Salt Valley, containing a diapiric salt anticline; and Lisbon Valley, containing a non-diapiric salt anticline. During current Phase II area studies, the four study areas are being characterized in greater detail than in Phase I. Phase II will culminate in the identification of a potentially suitable location(s), if any, that will be recommended for study in still greater detail in a subsequent phase of work. 5 refs
Building on existing institutions to perpetuate knowledge of waste repositories

International Nuclear Information System (INIS)

Weitzberg, A.

1982-08-01

Purpose of this report is to examine the function of several existing institutions and to show how they could be effectively used to transmit information about waste repositories for long times into the future. Scope of this report is limited to a discussion of four institutional approaches to the dissemination and retention of information: Widely distributed maps, the marker system of the National Geodetic Survey, the archiving of documents, and one-call systems designed to protect underground utility installations from inadvertent damage by the public. Each of these approaches is discussed in an independent section that describes the background of the institutional approach, discusses methods for applying it to waste repositories, and assesses its potential value. The sole intent of this report is to present supporting data for future decisions about the kinds of communication measures that should be implemented to advise future generations about the locations and hazards of waste repositories
Use of a United States mid-Pacific Island territory for a Pacific Island Repository System (PIRS): Extended summary

International Nuclear Information System (INIS)

Forsberg, C.W.

1987-08-01

The concept of using a mid-ocean island for a geologic high-level waste repository was investigated. The technical advantages include geographical isolation and near-infinite ocean dilution as a backup to repository geological waste isolation. The institutional advantages are reduced siting problems and the potential of creating an international waste repository. Establishment of international waste repository would allow cost sharing, aid US nonproliferation goals, and assure proper disposal of spent fuel from developing countries. The major uncertainties in this concept are rock conditions at waste disposal depths and costs. 13 refs., 2 tabs
Review. Deep repository for spent nuclear fuel SR 97 - Post-closure safety

International Nuclear Information System (INIS)

Stephansson, Ove

2000-01-01

SKB states that the chosen scenarios provide good coverage of future evolutionary pathways for the deep repository. This is not the case. SKB has not made full use of the established interaction matrices and the new method of THMC diagrams to generate the relevant and important scenarios and to construct the important pathways of variables and processes, either in the established interaction matrices and the presented THMC diagrams. Hence, SKB is demonstrating in SR 97 that they lack a well thought through, sound and solid method to select and evaluate scenarios for the purpose of demonstrating the safety of a deep repository for spent nuclear fuel. The evolution of the system is presented for the components of the repository system (fuel, canister, buffer/backfill, geosphere) and the effects of four different scenarios, but time only enters into the system for discrete events or processes, e.g. description of the relative radiotoxicity and heat decay of the fuel, temperature distribution, iron exchange process, pH in buffer, redox capacity and radionuclear release at the three sites. There is a lack of method and way of describing the evolution of the complete repository system, including the major scenarios, as a function of time. It is essential that SKB is able to: - consider the full range of potential scenarios, - grade the scenarios according to their significance for repository design and performance and safety assessment, - consider whether simple engineering actions could be taken to inhibit the development of adverse scenarios. This cannot be done with the system presented in SR 97, and so SKB do not have a full predictive capability - which is required for the engineering design of such an important and costly structure as a repository. Geoscientific investigation material for three selected sites are presented by SKB in the technical report dealing with waste, repository design and sites. Here a general overview is missing of the geological and rock
National waste terminal storage conceptual reference repository description

International Nuclear Information System (INIS)

Odgers, I.L.; Collings, J.L.

1981-01-01

The conceptual reference repository description (CRRD) discusses, from a conceptual engineering standpoint, the structures, systems, equipment, and operations necessary to: (1) receive unreprocessed spent fuel assemblies in standard casks; (2) unload these assemblies; (3) place them in canisters; (4) transport the canisters to underground storage locations in the salt dome; and (5) place the canisters in terminal storage. The CRRD also elaborates on the concepts for retrieval and recovery of the spent fuel after burial and describes the development of the shafts and the underground areas, as well as the supporting operational utility and administrative features of the repository
The physical and chemical environment and radionuclide migration in a low level radioactive waste repository

International Nuclear Information System (INIS)

Torok, J.; Buckley, L.P.

1988-01-01

The expected physical and chemical environment within the low-level radioactive waste repository to be sited at Chalk River is being studied to establish the rate of radionuclide migration. Chemical conditions in the repository are being assessed for their effect on buffer performance and the degradiation of the concrete structure. Experimental programs include the effect of changes in solution chemistry on radionuclide distribution between buffer/backfill materials and the aqueous phase; the chemical stability of the buffer materials and the determination of the controlling mechanism for radionuclide transport during infiltration
Corrosion of the copper canister in the repository environment

Energy Technology Data Exchange (ETDEWEB)

Hermansson, H.P.; Eriksson, Sture [Studsvik Material AB, Nykoeping (Sweden)

1999-12-01

The present report accounts for studies on copper corrosion performed at Studsvik Material AB during 1997-1999 on commission by SKI. The work has been focused on localised corrosion and electrochemistry of copper in the repository environment. The current theory of localised copper corrosion is not consistent with recent practical experiences. It is therefore desired to complete and develop the theory based on knowledge about the repository environment and evaluations of previous as well as recent experimental and field results. The work has therefore comprised a thorough compilation and up-date of literature on copper corrosion and on the repository environment. A selection of a 'working environment', defining the chemical parameters and their ranges of variation has been made and is used as a fundament for the experimental part of the work. Experiments have then been performed on the long-range electrochemical behaviour of copper in selected environments simulating the repository. Another part of the work has been to further develop knowledge about the thermodynamic limits for corrosion in the repository environment. Some of the thermodynamic work is integrated here. Especially thermodynamics for the system Cu-Cl-H-O up to 150 deg C and high chloride concentrations are outlined. However, there is also a rough overview of the whole system Cu-Fe-Cl-S-C-H-O as a fundament for the discussion. Data are normally accounted as Pourbaix diagrams. Some of the conclusions are that general corrosion on copper will probably not be of significant importance in the repository as far as transportation rates are low. However, if such rates were high, general corrosion could be disastrous, as there is no passivation of copper in the highly saline environment. The claim on knowledge of different kinds of localised corrosion and pitting is high, as pitting damages can shorten the lifetime of a canister dramatically. Normal pitting can happen in oxidising environment, but
Corrosion of the copper canister in the repository environment

International Nuclear Information System (INIS)

Hermansson, H.P.; Eriksson, Sture

1999-12-01

The present report accounts for studies on copper corrosion performed at Studsvik Material AB during 1997-1999 on commission by SKI. The work has been focused on localised corrosion and electrochemistry of copper in the repository environment. The current theory of localised copper corrosion is not consistent with recent practical experiences. It is therefore desired to complete and develop the theory based on knowledge about the repository environment and evaluations of previous as well as recent experimental and field results. The work has therefore comprised a thorough compilation and up-date of literature on copper corrosion and on the repository environment. A selection of a 'working environment', defining the chemical parameters and their ranges of variation has been made and is used as a fundament for the experimental part of the work. Experiments have then been performed on the long-range electrochemical behaviour of copper in selected environments simulating the repository. Another part of the work has been to further develop knowledge about the thermodynamic limits for corrosion in the repository environment. Some of the thermodynamic work is integrated here. Especially thermodynamics for the system Cu-Cl-H-O up to 150 deg C and high chloride concentrations are outlined. However, there is also a rough overview of the whole system Cu-Fe-Cl-S-C-H-O as a fundament for the discussion. Data are normally accounted as Pourbaix diagrams. Some of the conclusions are that general corrosion on copper will probably not be of significant importance in the repository as far as transportation rates are low. However, if such rates were high, general corrosion could be disastrous, as there is no passivation of copper in the highly saline environment. The claim on knowledge of different kinds of localised corrosion and pitting is high, as pitting damages can shorten the lifetime of a canister dramatically. Normal pitting can happen in oxidising environment, but there is
Two-phase flow in fractured rock

International Nuclear Information System (INIS)

Davies, P.; Long, J.; Zuidema, P.

1993-11-01

This report gives the results of a three-day workshop on two-phase flow in fractured rock. The workshop focused on two-phase flow processes that are important in geologic disposal of nuclear waste as experienced in a variety of repository settings. The goals and objectives of the workshop were threefold: exchange information; describe the current state of understanding; and identify research needs. The participants were divided into four subgroups. Each group was asked to address a series of two-phase flow processes. The following groups were defined to address these processes: basic flow processes; fracture/matrix interactions; complex flow processes; and coupled processes. For each process, the groups were asked to address these four issues: (1) describe the two-phase flow processes that are important with respect to repository performance; (2) describe how this process relates to the specific driving programmatic issues given above for nuclear waste storage; (3) evaluate the state of understanding for these processes; and (4) suggest additional research to address poorly understood processes relevant to repository performance. The reports from each of the four working groups are given here
Groundwater flow modelling of the excavation and operational phases - Forsmark

Energy Technology Data Exchange (ETDEWEB)

Svensson, Urban (Computer-aided Fluid Engineering AB, Lyckeby (Sweden)); Follin, Sven (SF GeoLogic AB, Taeby (Sweden))

2010-07-15

As a part of the license application 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 climate conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. The modelling study reported here presents calculated inflow rates, drawdown of the groundwater table and upconing of deep saline water for different levels of grouting efficiency during the excavation and operational phases of a final repository at Forsmark. The inflow calculations are accompanied by a sensitivity study, which among other matters handles the impact of parameter heterogeneity, different deposition hole rejection criteria, and the SFR facility (the repository for short-lived radioactive waste located approximately 1 km to the north of the investigated candidate area for a final repository at Forsmark). The report also presents tentative modelling results for the duration of the saturation phase, which starts once the used parts of the repository are being backfilled.
Groundwater flow modelling of the excavation and operational phases - Forsmark

International Nuclear Information System (INIS)

Svensson, Urban; Follin, Sven

2010-07-01

As a part of the license application 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 climate conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. The modelling study reported here presents calculated inflow rates, drawdown of the groundwater table and upconing of deep saline water for different levels of grouting efficiency during the excavation and operational phases of a final repository at Forsmark. The inflow calculations are accompanied by a sensitivity study, which among other matters handles the impact of parameter heterogeneity, different deposition hole rejection criteria, and the SFR facility (the repository for short-lived radioactive waste located approximately 1 km to the north of the investigated candidate area for a final repository at Forsmark). The report also presents tentative modelling results for the duration of the saturation phase, which starts once the used parts of the repository are being backfilled
Multiphase flow in the geosphere around a repository for spent nuclear fuels. Inventory of the present knowledge

International Nuclear Information System (INIS)

Aalen, Bengt

2004-10-01

Important quantities of gas can form in an underground repository for nuclear wastes. Gas can be formed through: corroding metals; water and certain organic substances that undergo radiolysis; organic material degrading through microbial activity. The last point is of concern mainly for intermediate-level wastes, which can hold large amounts of organic materials. The first point is the main process for high-level wastes. The gas could transport radioactive substances through the buffer and the geosphere into the biosphere, or affect the performance of the repository in a negative way. The present report gives a review of the knowledge about two-phase flow in connection with deep geologic repositories for spent nuclear fuel
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.
Influence of Groundwater Flow Rate on Nuclide Releases from Pyro-processed Waste Repository

International Nuclear Information System (INIS)

Lee, Youn Myoung; Jeong, Jong Tae

2011-01-01

Since the early 2000s several template programs for the safety assessment of a high-level radioactive waste repository as well as a low- and intermediate level radioactive waste repository systems have been developed by utilizing GoldSim and AMBER at KAERI. Very recently, another template program for a conceptual hybrid-typed repository system, called 'A-KRS' in which two kinds of pyroprocessed radioactive wastes, low-level metal wastes and ceramic high-level wastes that arise from pyroprocessing of PWR nuclear spent fuels has been developed and are to be disposed of by separate disposal strategies. The A-KRS is considered to be constructed at two different depths in geological media: 200m depth, at which a possible human intrusion is considered to be limited after closure, for the pyroprocessed metal wastes with lower or no decay heat producing nuclides, and 500m depth, believed to be in the reducing condition for nuclides with a rather higher radioactivity and heat generation rate. This program is ready for total system performance assessment which is able to evaluate nuclide release from the repository and farther transport into the geosphere and biosphere under various normal, disruptive natural and manmade events, and scenarios that can occur after a failure of waste package and canister. To quantify a nuclide release and transport through the possible various pathways especially in the near-fields of the A-KRS repository system, some illustrative evaluations have been made through the study. Even though all parameter values associated with the A-KRS were assumed for the time being, the illustrative results should be informative since the evaluation of such releases is very important not only in view of the safety assessment of the repository, but also for design feedback of its performance
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)
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...
Effective summary evaluators for deep nuclear waste repositories: geohydrologic response function

International Nuclear Information System (INIS)

Nelson, R.W.; Dove, F.H.

1981-03-01

Useful insight has been gained over the past four years as hydrologic system modeling has been applied to evaluate hypothetical, waste-repository sites in various geologic media. The Geohydrologic Response Functions, described in this paper, are shown to: blend extensive results of technical analysis into simple summary relationships, and to potentially help the public and decision makers to evaluate the magnitude of any loss in repository integrity
Waste inventory, waste characteristics and waste repositories in Japan

International Nuclear Information System (INIS)

Shimooka, K.

1997-01-01

There are two types of repositories for the low level radioactive wastes in Japan. One is a trench type repository only for concrete debris generated from the dismantling of the research reactor. According to the safety assurance system, Japan Atomic Energy Research Institute (JAERI) has disposed of the concrete debris arose from the dismantling of the Japan Power Demonstration Reactor (JPDR). The other type is the concreted pit with engineered barriers. Rokkasho Low Level Radioactive Waste Disposal Center has this type of repository mainly for the power plant wastes. Japan Nuclear Fuel Ltd. (JNFL) established by electric power companies is the operator of the LLW disposal project. JNFL began the storage operation in 1992 and buried approximately 60,000 drums there. Two hundred thousand drums of uniformly solidified, waste may be buried ultimately. 4 refs, 3 tabs
Backfilling and closure of the deep repository. Assessment of backfill concepts

International Nuclear Information System (INIS)

Gunnarsson, David; Boergesson, Lennart; Keto, Paula; Tolppanen, Pasi; Hansen, Johanna

2004-06-01

This report presents the results from work made in Phase 1 of the joint SKB-Posiva project 'Backfilling and Closure of the Deep Repository' aiming at selecting and developing materials and techniques for backfilling and closure of a KBS-3 type repository for spent nuclear fuel. The aim of phase 1, performed as a desk study, was to describe the potential of the suggested backfill concepts in terms of meeting SKB and Posiva requirements, select the most promising ones for further investigation, and to describe methods that can be used for determining the performance of the concepts. The backfilling concepts described in this report differ from each other with respect to backfill materials and installation techniques. The concepts studied are the following: Concept A: Compaction of a mixture of bentonite and crushed rock in the tunnel. Concept B: Compaction of natural clay with swelling ability in the tunnel. Concept C: Compaction of non-swelling soil type in the tunnel combined with application of pre-compacted bentonite blocks at the roof. Concept D: Placement of pre-compacted blocks; a number of materials are considered. Concept E: Combination of sections consisting of a) crushed rock compacted in the tunnel and b) pre-compacted bentonite blocks. The bentonite sections are installed regularly above every disposal hole. Concept F: Combination of sections consisting of a) crushed rock compacted in the tunnel and b) pre-compacted bentonite blocks. The distance between the bentonite sections is adapted to the local geology and hydrology.The assessment of the concepts is based on performance requirements set for the backfill in the deposition tunnels for providing a stable and safe environment for the bentonite buffer and canister for the repository service time. In order to do this, the backfill should follow certain guidelines, 'design criteria' concerning compressibility, hydraulic conductivity, swelling ability, long-term stability, effects on the barriers and

Backfilling and closure of the deep repository. Assessment of backfill concepts

Energy Technology Data Exchange (ETDEWEB)

Gunnarsson, David; Boergesson, Lennart [Clay Technology AB, Lund (Sweden); Keto, Paula [Saanio Riekkola Oy (Finland); Tolppanen, Pasi [Jaakko Poeyry Infra (Finland); Hansen, Johanna [Posiva Oy, Helsinki (Finland)

2004-06-01

This report presents the results from work made in Phase 1 of the joint SKB-Posiva project 'Backfilling and Closure of the Deep Repository' aiming at selecting and developing materials and techniques for backfilling and closure of a KBS-3 type repository for spent nuclear fuel. The aim of phase 1, performed as a desk study, was to describe the potential of the suggested backfill concepts in terms of meeting SKB and Posiva requirements, select the most promising ones for further investigation, and to describe methods that can be used for determining the performance of the concepts. The backfilling concepts described in this report differ from each other with respect to backfill materials and installation techniques. The concepts studied are the following: Concept A: Compaction of a mixture of bentonite and crushed rock in the tunnel. Concept B: Compaction of natural clay with swelling ability in the tunnel. Concept C: Compaction of non-swelling soil type in the tunnel combined with application of pre-compacted bentonite blocks at the roof. Concept D: Placement of pre-compacted blocks; a number of materials are considered. Concept E: Combination of sections consisting of a) crushed rock compacted in the tunnel and b) pre-compacted bentonite blocks. The bentonite sections are installed regularly above every disposal hole. Concept F: Combination of sections consisting of a) crushed rock compacted in the tunnel and b) pre-compacted bentonite blocks. The distance between the bentonite sections is adapted to the local geology and hydrology.The assessment of the concepts is based on performance requirements set for the backfill in the deposition tunnels for providing a stable and safe environment for the bentonite buffer and canister for the repository service time. In order to do this, the backfill should follow certain guidelines, 'design criteria' concerning compressibility, hydraulic conductivity, swelling ability, long-term stability, effects on
Thermal Analysis of a Nuclear Waste Repository in Argillite Host Rock

Science.gov (United States)

Hadgu, T.; Gomez, S. P.; Matteo, E. N.

2017-12-01

Disposal of high-level nuclear waste in a geological repository requires analysis of heat distribution as a result of decay heat. Such an analysis supports design of repository layout to define repository footprint as well as provide information of importance to overall design. The analysis is also used in the study of potential migration of radionuclides to the accessible environment. In this study, thermal analysis for high-level waste and spent nuclear fuel in a generic repository in argillite host rock is presented. The thermal analysis utilized both semi-analytical and numerical modeling in the near field of a repository. The semi-analytical method looks at heat transport by conduction in the repository and surroundings. The results of the simulation method are temperature histories at selected radial distances from the waste package. A 3-D thermal-hydrologic numerical model was also conducted to study fluid and heat distribution in the near field. The thermal analysis assumed a generic geological repository at 500 m depth. For the semi-analytical method, a backfilled closed repository was assumed with basic design and material properties. For the thermal-hydrologic numerical method, a repository layout with disposal in horizontal boreholes was assumed. The 3-D modeling domain covers a limited portion of the repository footprint to enable a detailed thermal analysis. A highly refined unstructured mesh was used with increased discretization near heat sources and at intersections of different materials. All simulations considered different parameter values for properties of components of the engineered barrier system (i.e. buffer, disturbed rock zone and the host rock), and different surface storage times. Results of the different modeling cases are presented and include temperature and fluid flow profiles in the near field at different simulation times. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and
Prediction of inflow into the ONKALO and the repository during 2014-2125

International Nuclear Information System (INIS)

Pentti, E.; Ahokas, H.

2014-04-01

Inflow of groundwater into the planned repository for spent nuclear fuel at Olkiluoto has been estimated until its closure in the 2120's. The estimation is based on statistics on fractures and their transmissivities observed in drillholes at the site, on a realistic time dependence of the length of open tunnels throughout the operational period of the repository, and on measured inflows into already excavated rooms. The effect of two hydrogeological zones penetrated by central tunnels has also been estimated deterministically to complement the statistical analysis. Inflow into the ONKALO is estimated to reach 45 l/min by 2020 with the completion of all four vertical shafts, and expected to remain at that level until the closure of the repository. During the operational period, c. 2020-2120, inflow into central tunnels and deposition tunnels will vary with their phased excavation and backfilling. On the basis of statistical modelling of fracture data, two values for inflow per tunnel length were determined and used to predict the range of total inflow into the repository: 2 l/min/km for grouted high-quality rock and 6 l/min/km for ungrouted rock with slight fracturing. These values are in good agreement with earlier inflow estimates. The predicted total inflow into the repository ranges from 50 to 80 l/min until 2100, and after that from 60 to 100 l/min. The increase is due to penetration of hydrogeological zone HZ20. Intersections of central tunnels with the proposed zone extension HZ056ext would cause an additional inflow on the order of 5 l/min. (orig.)
U.S. DEPARTMENT OF ENERGY EXPERIENCE IN CREATING AND COMMUNICATING THE CASE FOR THE SAFETY OF A POTENTIAL YUCCA MOUNTAIN REPOSITORY

International Nuclear Information System (INIS)

W.J. Boyle; A.E. Van Luik

2005-01-01

Experience gained by the U.S. Department of Energy (the Department) in making the recommendation for the development of the Yucca Mountain site as the nation's first high-level waste and spent nuclear fuel repository is useful for creating documents to support the next phase in the repository program, the licensing phase. The experience that supported the successful site-recommendation process involved a three-tiered approach. First, was making a highly technical case for regulatory compliance. Second, was making a broader case for safety in an Environmental Impact Statement. And third, producing plain language brochures, made available to the public in hard copy and on the Internet, to explain the Department's action and its legal and scientific bases. This paper reviews lessons learned from this process, and makes suggestions for the next stage of the repository program: licensing
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)
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.
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.
Results From an International Simulation Study on Coupled Thermal, Hydrological, and Mechanical (THM) Processes Near Geological Nuclear Waste Repositories

International Nuclear Information System (INIS)

J. Rutqvist; D. Barr; J.T. Birkholzer; M. Chijimatsu; O. Kolditz; Q. Liu; Y. Oda; W. Wang; C. Zhang

2006-01-01

As part of the ongoing international DECOVALEX project, four research teams used five different models to simulate coupled thermal, hydrological, and mechanical (THM) processes near waste emplacement drifts of geological nuclear waste repositories. The simulations were conducted for two generic repository types, one with open and the other with back-filled repository drifts, under higher and lower postclosure temperatures, respectively. In the completed first model inception phase of the project, a good agreement was achieved between the research teams in calculating THM responses for both repository types, although some disagreement in hydrological responses is currently being resolved. In particular, good agreement in the basic thermal-mechanical responses was achieved for both repository types, even though some teams used relatively simplified thermal-elastic heat-conduction models that neglected complex near-field thermal-hydrological processes. The good agreement between the complex and simplified process models indicates that the basic thermal-mechanical responses can be predicted with a relatively high confidence level
Uncertainty management in radioactive waste repository site assessment

International Nuclear Information System (INIS)

Baldwin, J.f.; Martin, T.P.; Tocatlidou

1994-01-01

The problem of performance assessment of a site to serve as a repository for the final disposal of radioactive waste involves different types of uncertainties. Their main sources include the large temporal and spatial considerations over which safety of the system has to be ensured, our inability to completely understand and describe a very complex structure such as the repository system, lack of precision in the measured information etc. These issues underlie most of the problems faced when rigid probabilistic approaches are used. Nevertheless a framework is needed, that would allow for an optimal aggregation of the available knowledge and an efficient management of the various types of uncertainty involved. In this work a knowledge-based modelling of the repository selection process is proposed that through a consequence analysis, evaluates the potential impact that hypothetical scenarios will have on a candidate site. The model is organised around a hierarchical structure, relating the scenarios with the possible events and processes that characterise them, and the site parameters. The scheme provides for both crisp and fuzzy parameter values and uses fuzzy semantic unification and evidential support logic reference mechanisms. It is implemented using the artificial intelligence language FRIL and the interaction with the user is performed through a windows interface
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)
Integrated web-based viewing and secure remote access to a clinical data repository and diverse clinical systems.

Science.gov (United States)

Duncan, R G; Saperia, D; Dulbandzhyan, R; Shabot, M M; Polaschek, J X; Jones, D T

2001-01-01

The advent of the World-Wide-Web protocols and client-server technology has made it easy to build low-cost, user-friendly, platform-independent graphical user interfaces to health information systems and to integrate the presentation of data from multiple systems. The authors describe a Web interface for a clinical data repository (CDR) that was moved from concept to production status in less than six months using a rapid prototyping approach, multi-disciplinary development team, and off-the-shelf hardware and software. The system has since been expanded to provide an integrated display of clinical data from nearly 20 disparate information systems.
Climate Considerations in Long-Term Safety Assessments for Nuclear Waste Repositories

Energy Technology Data Exchange (ETDEWEB)

Naeslund, Jens-Ove; Brandefelt, Jenny; Claesson Liljedahl, Lillemor [Svensk Kaernbraenslehantering AB, Stockholm (Sweden)], E-mail: jens-ove.naslund@skb.se

2013-05-15

For a deep geological repository for spent nuclear fuel planned in Sweden, the safety assessment covers up to 1 million years. Climate scenarios range from high-end global warming for the coming 100 000 years, through deep permafrost, to large ice sheets during glacial conditions. In contrast, in an existing repository for short-lived waste the activity decays to low levels within a few tens of thousands of years. The shorter assessment period, 100 000 years, requires more focus on climate development over the coming tens of thousands of years, including the earliest possibility for permafrost growth and freezing of the engineered system. The handling of climate and climate change in safety assessments must be tailor-made for each repository concept and waste type. However, due to the uncertain future climate development on these vast time scales, all safety assessments for nuclear waste repositories require a range of possible climate scenarios.
The Yucca Mountain Repository - Too Little, Too Late

International Nuclear Information System (INIS)

Eriksson, L.G.; Pentz, D.L.

2009-01-01

In 2008, the U.S. Department of Energy (US DOE) announced that the nation's first (and only pursued) deep geological disposal system (repository) for 70,000 metric tonnes of spent nuclear fuel (SNF) and other high-level radioactive waste (HLW) at the Yucca Mountain (YM) site in Nevada would: 1. Not be able to accommodate the projected stockpile of utility-generated SNF beyond 2010. 2. Open no earlier than in 2020, i.e., more than 22 years behind the statutory-mandated opening date. In the meantime, the US DOE is legally obligated to compensate the utilities from January 31, 1998, until it takes title to the utilities' SNF. In 2005 when the YM SNF repository was projected to open in 2010, the utilities estimated that, depending upon how close to 2010 the YM repository opened, the 'breach-of-contract' compensation could be in the range of between 100 billion and 300 billion U.S. dollars ($300 B), which would exceed the 2008 projected life-cycle cost of $96 B for the YM repository. It thus seems appropriate to look beyond the YM repository and call upon the U.S. Congress to promptly act and open new avenues allowing the US DOE to more timely and cost-effectively take title to both existing and pending SNF the current fleet of 104 reactors will generate through the next 60 years. Options for SNF arising from an additional 50 reactors should also be provided. Based on our more than 60 years of combined involvement in nuclear waste management in the USA and abroad, we submit the following industrial-scale-proven, repository-related, nuclear-waste-management and disposition solutions for prompt Congressional consideration and action: 1. An increase in the disposal capacity (and perhaps mission) of the YM repository. 2. Prompt establishment of at least one large federal monitored retrievable storage (MRS) facility for utility-generated SNF. 3. Continued research in reprocessing options of existing and pending SNF with defined milestones. 4. Resurrection of a second
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 ï¬‚owing over the network; little thoughts are made regarding the consistency of these repositories. Still, for
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.
Evaluation of Nuclide Release Scenarios for a Hypothetical LILW Repository

International Nuclear Information System (INIS)

Lee, Youn Myoung; Jeong, Jong Tae

2010-11-01

A program for the safety assessment and performance evaluation of a low- and intermediate-level radioactive waste (LILW) repository system has been developed. Utilizing GoldSim (GoldSim, 2006), the program evaluates nuclide release and transport into the geosphere and biosphere under various disruptive natural and manmade events and scenarios that can occur after a waste package failure. We envisaged and illustrated these events and scenarios as occurring after the closure of a hypothetical LILW repository, and they included the degradation of various manmade barriers, pumping well drilling, and natural disruptions such as the sudden formation of a preferential flow pathway in the far-field area of the repository. Possible enhancement of nuclide transport facilitated by colloids or chelating agents is also dealt with. We used the newly-developed GoldSim template program, which is capable of various nuclide release scenarios and is greatly suited for simulating a potential repository given the geological circumstances in Korea, to create the detailed source term and near-field release scheme, various nuclide transport modes in the far-field geosphere area, and the biosphere transfer. Even though all parameter values applied to the hypothetical repository were assumed, the illustrative results, particularly the probabilistic calculations and sensitivity studies, may be informative under various scenarios
Modelling Coupled Processes in the Evolution of Repository Engineered Barrier Systems using QPAC-EBS

Energy Technology Data Exchange (ETDEWEB)

Maul, Philip; Benbow, Steven; Bond, Alex; Robinson, Peter (Quintessa Limited, Henley-on-Thames (United Kingdom))

2010-08-15

A satisfactory understanding of the evolution of repository engineered barrier systems (EBS) is an essential part of the safety case for the repository. This involves consideration of coupled Thermal (T), Hydro (H), Mechanical (M) and Chemical (C) processes. Quintessa's general-purpose modelling code QPAC is capable of representing strongly coupled non-linear processes and has been used in a wide range of applications. This code is the basis for software used by Quintessa in studies of the evolution of the EBS in a deep repository for spent nuclear fuel undertaken for SKI and then SSM since 2007. The collection of software components employed has been referred to collectively as QPAC-EBS, consisting of the core QPAC code together with relevant modules for T, H, M and C processes. QPAC-EBS employs a fundamentally different approach from dedicated codes that model such processes (although few codes can represent each type of process), enabling the specification of new processes and the associated governing equations in code input. Studies undertaken to date have demonstrated that QPAC-EBS can be used effectively to investigate both the early evolution of the EBS and important scenarios for the later evolution of the system when buffer erosion and canister corrosion may occur. A key issue for modelling EBS evolution is the satisfactory modelling of the behaviour of the bentonite buffer. Bentonite is a difficult material to model, partly because of the complex coupled mechanical, hydro and chemical processes involved in swelling during resaturation. Models employed to date have generally taken an empirical approach, but a new model developed during the EU THERESA project could be further developed to provide a better representation of these processes. QPAC-EBS could play an important role in supporting SSM.s review of the forthcoming SR-Site assessment by SKB if used by Quintessa in independent supporting calculations. To date radionuclide transport calculations
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
Development of an Integrated Natural Barrier Database System for Site Evaluation of a Deep Geologic Repository in Korea - 13527

International Nuclear Information System (INIS)

Jung, Haeryong; Lee, Eunyong; Jeong, YiYeong; Lee, Jeong-Hwan

2013-01-01

Korea Radioactive-waste Management Corporation (KRMC) established in 2009 has started a new project to collect information on long-term stability of deep geological environments on the Korean Peninsula. The information has been built up in the integrated natural barrier database system available on web (www.deepgeodisposal.kr). The database system also includes socially and economically important information, such as land use, mining area, natural conservation area, population density, and industrial complex, because some of this information is used as exclusionary criteria during the site selection process for a deep geological repository for safe and secure containment and isolation of spent nuclear fuel and other long-lived radioactive waste in Korea. Although the official site selection process has not been started yet in Korea, current integrated natural barrier database system and socio-economic database is believed that the database system will be effectively utilized to narrow down the number of sites where future investigation is most promising in the site selection process for a deep geological repository and to enhance public acceptance by providing readily-available relevant scientific information on deep geological environments in Korea. (authors)
Development of the Korean Reference Vertical Disposal System Concept for Spent Fuels

International Nuclear Information System (INIS)

Lee, J.Y.; Cho, D.K.; Kim, S.G.; Choi, H.J.; Choi, J.W.; Hahn, P.S.

2006-01-01

The development of a deep geologic disposal system for the spent fuel from nuclear power plants has been carried out since this program was launched at 1997 in Korea. In ' this paper, a pre-conceptual design of the Korean Reference HLW Vertical disposal System (KRS-V1) is presented. Though no site for the underground repository has yet been specified in Korea, a generic site with granitic rock is considered for reference HLW repository design. Depth of the repository is assumed to be 500 meters. The repository consists of the disposal area, technical rooms with four shafts to connect them to the ground level in the controlled area and technical rooms with an access tunnel and three shafts to connect them to the ground level in the uncontrolled area. Disposal area consists of disposal tunnels, panel tunnels and a central tunnel. The repository will be excavated, operated and backfilled in several phases including an Underground Research Laboratory (URL) phase. The result of this preliminary conceptual design will be used for an evaluation of the feasibility, analyses of the long term safety, information for public communication and a cost estimation etc. (authors)

A logistic and cost model for the transport of radioactive waste to a repository

International Nuclear Information System (INIS)

Hutchinson, D.L.; Gray, I.L.S.; Manville, W.D.

1997-01-01

UK Nirex Ltd is planning a deep repository for intermediate level radioactive waste, and also some low level waste. Part of this work is to develop a transport system to bring the packaged waste to the repository from nuclear industry sites across the United Kingdom. To assess the logistics and costs of this transport system and to provide inputs to the repository specification and design, Nirex has commissioned the development of a flexible computer model which can be used on a desktop PC. The requirements for the LOGCOST model are explained, and the solutions adopted, and then examples shown of the graphical and tabular outputs that LOGCOST can provide. (Author)
Technical conservatism in the design and analysis of a nuclear-waste repository in basalt

International Nuclear Information System (INIS)

Jones, K.A.

1982-01-01

The US Department of Energy's National Waste Terminal Storage Program has adopted a policy of technical conservatism to guide the design and analysis of geologic disposal systems for commercial high-level radioactive waste. Technical conservatism serves as the programmatic philosophy for managing uncertainty in the performance of the disposal system. The implementation of technical conservatism as applied to a nuclear waste repository in basalt is discussed. Preliminary assessments of the performance of the waste package, repository, and site subsystems are compared to key proposed regulatory criteria. The comparison shows that there are substantial safety margins in the predicted performance of the nuclear waste repository in basalt
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
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
Implementing the EuroFIR Document and Data Repositories as accessible resources of food composition information.

Science.gov (United States)

Unwin, Ian; Jansen-van der Vliet, Martine; Westenbrink, Susanne; Presser, Karl; Infanger, Esther; Porubska, Janka; Roe, Mark; Finglas, Paul

2016-02-15

The EuroFIR Document and Data Repositories are being developed as accessible collections of source documents, including grey literature, and the food composition data reported in them. These Repositories will contain source information available to food composition database compilers when selecting their nutritional data. The Document Repository was implemented as searchable bibliographic records in the Europe PubMed Central database, which links to the documents online. The Data Repository will contain original data from source documents in the Document Repository. Testing confirmed the FoodCASE food database management system as a suitable tool for the input, documentation and quality assessment of Data Repository information. Data management requirements for the input and documentation of reported analytical results were established, including record identification and method documentation specifications. Document access and data preparation using the Repositories will provide information resources for compilers, eliminating duplicated work and supporting unambiguous referencing of data contributing to their compiled data. Copyright © 2014 Elsevier Ltd. All rights reserved.
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)
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
Investigation on long-term safety aspects of a radioactive waste repository in a diagenic clay formation. Final report

Energy Technology Data Exchange (ETDEWEB)

Jobmann, M.; Gazul, R. [DBE Technology GmbH, Peine (Germany); Fluegge, J. [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) gGmbH, Braunschweig (Germany); and others

2017-03-28

The report presents the sealing concept developed for a Russian near surface low/intermediate level (LILW) waste repository at the ''radon site'' in the lower Cambrian ''blue clay'' formation. The radioactive wastes will be transported to the repository through a tunnel that will connect the underground disposal areas with the surface facilities. Two ventilation shafts for fresh and exhaust air will also connect the underground facilities with the surface. Specific characteristics of the flow regime in the studied area have been simulated. For the construction of a potential repository site it is necessary to know the possible contaminant transport paths to the surface and the biosphere. Due to the lack of sufficient data the calculation can only indicate tendencies that can trigger future explorations. Simulations of the radionuclide (C-14, Cl-36, Se-79, I-129) release from the repository in the liquid phase show a similar behavior as for other repositories in clay. Probabilistic simulations show a large variation of obtained results as a result of the parameter uncertainty.
Investigation of two-phase flow phenomena associated with corrosion in an SF/HLW repository in Opalinus Clay, Switzerland

International Nuclear Information System (INIS)

Senger, R.; Marschall, P.; Finsterle, S.

2008-01-01

Gas generation from corrosion of the waste canisters and gas accumulation in the backfilled emplacement tunnels is a key issue in the assessment of long-term radiological safety of the proposed repository for spent fuel and high-level waste (SF/HLW) sited in the Opalinus Clay formation of Northern Switzerland. Previous modeling studies indicated a significant pressure buildup in the backfilled emplacement tunnels for those sensitivity runs, where corrosion rates were high and the permeability of the Opalinus Clay was very low. As an extension to those studies, a refined process model of the canister corrosion phenomena has been developed, which accounts not only for the gas generation but also for the water consumption associated with the chemical reaction of corrosion of steel under anaerobic conditions. The simulations with the new process model indicate, that with increasing corrosion rates and decreasing host-rock permeability, pressure buildup increased, as expected. However, the simulations taking into account water consumption show that the pressure buildup is reduced compared to the simulation considering only gas generation. The pressure reduction is enhanced for lower permeability of the Opalinus Clay and for higher corrosion rates, which correspond to higher gas generations rates and higher water consumption rates. Moreover, the simulated two-phase flow patterns in the engineered barrier system (EBS) and surrounding Opalinus Clay show important differences at late time of the gas production phase as the generated gas continues to migrate outward into the surrounding host rock. For the case without water consumption, the water flow indicates overall downward flow due to a change in the overall density of the gas-fluid mixture from that based on the initially prescribed hydrostatic pressure gradient. For the case with water consumption, water flow converges toward the waste canister at a rate corresponding to the water consumption rate associated with the
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
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
Information basis for developing comprehensive waste management system-US-Japan joint nuclear energy action plan waste management working group phase I report.

Energy Technology Data Exchange (ETDEWEB)

Nutt, M.; Nuclear Engineering Division

2010-05-25

The activity of Phase I of the Waste Management Working Group under the United States - Japan Joint Nuclear Energy Action Plan started in 2007. The US-Japan JNEAP is a bilateral collaborative framework to support the global implementation of safe, secure, and sustainable, nuclear fuel cycles (referred to in this document as fuel cycles). The Waste Management Working Group was established by strong interest of both parties, which arise from the recognition that development and optimization of waste management and disposal system(s) are central issues of the present and future nuclear fuel cycles. This report summarizes the activity of the Waste Management Working Group that focused on consolidation of the existing technical basis between the U.S. and Japan and the joint development of a plan for future collaborative activities. Firstly, the political/regulatory frameworks related to nuclear fuel cycles in both countries were reviewed. The various advanced fuel cycle scenarios that have been considered in both countries were then surveyed and summarized. The working group established the working reference scenario for the future cooperative activity that corresponds to a fuel cycle scenario being considered both in Japan and the U.S. This working scenario involves transitioning from a once-through fuel cycle utilizing light water reactors to a one-pass uranium-plutonium fuel recycle in light water reactors to a combination of light water reactors and fast reactors with plutonium, uranium, and minor actinide recycle, ultimately concluding with multiple recycle passes primarily using fast reactors. Considering the scenario, current and future expected waste streams, treatment and inventory were discussed, and the relevant information was summarized. Second, the waste management/disposal system optimization was discussed. Repository system concepts were reviewed, repository design concepts for the various classifications of nuclear waste were summarized, and the factors
Site selection for Canada's national repository for used nuclear fuel

International Nuclear Information System (INIS)

Ben Belfadhel, M.; Watts, B.; Facella, J.

2015-01-01

In 2007, the Government of Canada selected Adaptive Phased Management as Canada's plan for the long-term management of Canada's used nuclear fuel. The approach provides for containment and isolation of the material in a deep geological repository at a safe site with an informed and willing host. The Nuclear Waste Management Organization is tasked through federal legislation with selecting the site and developing and managing all aspects of the plan. In May 2010, the organization published and initiated the site selection process that serves as a road map for decision making on the location for the deep geological repository. It continues to lead the site selection process for the repository and an associated Centre of Expertise. The screening process is advancing and, from an initial starting point of 22 communities expressing interest in learning about the project; as of September 2015, 9 communities are the focus of more detailed technical and community well-being studies. Preliminary Assessments, the third step in the 9-step site selection process are underway in these communities. The Assessments involve preliminary technical and social desktop and field assessments, engagement activities within and beyond each interested community, and involvement of Indigenous peoples and nearby municipalities in the planning and conduct of the work. This paper provides an update on the advancement of the site selection process. It describes the nature of the technical and social studies being conducted at this phase of work, including the progressively more detailed field studies that are the focus of technical work at the current stage, the approach to engagement and collaboration with communities to direct these studies, and the work underway to ensure the framework used for this assessment and engagement includes the range of priorities and perspectives of First Nations and Metis peoples and communities in the broader area. (author)
Understanding the evolution of the repository and the olkiluoto site

International Nuclear Information System (INIS)

Koskinen, K.; Pastina, B.

2008-01-01

Posiva Safety Case is organised in a portfolio including ten main reports: Site, Spent Fuel Characteristics and Inventories, Canister Design, Repository Design, Process, Evolution of the Repository and the Site, Biosphere Assessment, Radionuclide Transport, Complementary Evaluations of Safety, and Summary. This portfolio constitutes the basis of the Preliminary Safety Assessment Report, which will be presented to the authorities in 2012 as part of the repository construction license application. The Evolution report [1], which is the focus of this paper, is the main advance in the Safety Case portfolio since the implementation of the Safety Case plan [2] in 2005. The report provides the status of current knowledge with respect to the evolution of the site and the engineered barrier system and highlights areas where better understanding is needed. (authors)
A Probabilistic Safety Assessment of a Pyro-processed Waste Repository

International Nuclear Information System (INIS)

Lee, Youn Myoung; Jeong, Jong Tae

2012-01-01

A GoldSim template program for a safety assessment of a hybrid-typed repository system, called A-KRS, in which two kinds of pyro-processed radioactive wastes, low-level metal wastes and ceramic high-level wastes that arise from the pyro-processing of PWR nuclear spent fuels are disposed of, has been developed. This program is ready both for a deterministic and probabilistic total system performance assessment which is able to evaluate nuclide release from the repository and farther transport into the geosphere and biosphere under various normal, disruptive natural and manmade events, and scenarios. The A-KRS has been probabilistically assessed with 9 selected input parameters, each of which has its own statistical distribution for a normal release and transport scenario associated with nuclide release and transport in and around the repository. Probabilistic dose exposure rates to the farming exposure group have been evaluated. A sensitivity of 9 selected parameters to the result has also been investigated to see which parameter is more sensitive and important to the exposure rates.
Climate considerations in long-term safety assessments for nuclear waste repositories.

Science.gov (United States)

Näslund, Jens-Ove; Brandefelt, Jenny; Liljedahl, Lillemor Claesson

2013-05-01

For a deep geological repository for spent nuclear fuel planned in Sweden, the safety assessment covers up to 1 million years. Climate scenarios range from high-end global warming for the coming 100 000 years, through deep permafrost, to large ice sheets during glacial conditions. In contrast, in an existing repository for short-lived waste the activity decays to low levels within a few tens of thousands of years. The shorter assessment period, 100 000 years, requires more focus on climate development over the coming tens of thousands of years, including the earliest possibility for permafrost growth and freezing of the engineered system. The handling of climate and climate change in safety assessments must be tailor-made for each repository concept and waste type. However, due to the uncertain future climate development on these vast time scales, all safety assessments for nuclear waste repositories require a range of possible climate scenarios.
Postcards from the past: Archaeological and industrial analogs for deep repository materials

International Nuclear Information System (INIS)

Miller, B.; Chapman, N.

1995-01-01

Many recent performance assessments of deep geological repositories for radioactive wastes suggest that the engineered barrier system plays the cominant role in reducing releases of radionuclides to the surface environment. There is a considerable impetus to demonstrate the longevity of engineered barrier system components. Although many of the materials are familiar, the requirement for predictable behavior and longevity in a repository is unlike any other requirements of the past. A full appreciation of the acceptability of repository materials can only be reached from a combination of complementary field, laboratory, and natural analog studies. This article discusses analogs from archaelogy and industry. Topics covered include what makes a good analog; long term material behavior (from archeological studies) of metals, glass,cements and concrete, bitumens, and betonite; investigations of radionuclide transport and material interactions. 4 figs., 3 tabs
SUMO, System performance assessment for a high-level nuclear waste repository: Mathematical models

International Nuclear Information System (INIS)

Eslinger, P.W.; Miley, T.B.; Engel, D.W.; Chamberlain, P.J. II.

1992-09-01

Following completion of the preliminary risk assessment of the potential Yucca Mountain Site by Pacific Northwest Laboratory (PNL) in 1988, the Office of Civilian Radioactive Waste Management (OCRWM) of the US Department of Energy (DOE) requested the Performance Assessment Scientific Support (PASS) Program at PNL to develop an integrated system model and computer code that provides performance and risk assessment analysis capabilities for a potential high-level nuclear waste repository. The system model that has been developed addresses the cumulative radionuclide release criteria established by the US Environmental Protection Agency (EPA) and estimates population risks in terms of dose to humans. The system model embodied in the SUMO (System Unsaturated Model) code will also allow benchmarking of other models being developed for the Yucca Mountain Project. The system model has three natural divisions: (1) source term, (2) far-field transport, and (3) dose to humans. This document gives a detailed description of the mathematics of each of these three divisions. Each of the governing equations employed is based on modeling assumptions that are widely accepted within the scientific community
Summary of four release consequence analyses for hypothetical nuclear waste repositories in salt and granite

International Nuclear Information System (INIS)

Cole, C.R.; Bond, F.W.

1980-12-01

Release consequence methology developed under the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) program has now been applied to four hypothetical repository sites. This paper summarizes the results of these four studies in order to demonstrate that the far-field methodology developed under the AEGIS program offers a practical approach to the post-closure safety assessment of nuclear waste repositories sited in deep continental geologic formations. The four studies are briefly described and compared according to the following general categories: physical description of the repository (size, inventory, emplacement depth); geologic and hydrologic description of the site and the conceptual hydrologic model for the site; description of release scenario; hydrologic model implementation and results; engineered barriers and leach rate modeling; transport model implementation and results; and dose model implementation and results. These studies indicate the following: numerical modeling is a practical approach to post-closure safety assessment analysis for nuclear waste repositories; near-field modeling capability needs improvement to permit assessment of the consequences of human intrusion and pumping well scenarios; engineered barrier systems can be useful in mitigating consequences for postulated release scenarios that short-circuit the geohydrologic system; geohydrologic systems separating a repository from the natural biosphere discharge sites act to mitigate the consequences of postulated breaches in containment; and engineered barriers of types other than the containment or absorptive type may be useful
Disruption scenarios for a high-level waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Ross, B.

1986-01-01

A high-level waste repository located in unsaturated welded tuff at Yucca Mountain, Nevada, would rely on six different, although not entirely independent, barriers to prevent escape of radioactivity. These barriers are the waste canister, fuel cladding, slow dissolution of the spent fuel itself, and slow movement of released contaminants in three different hydrogeologic units: the unsaturated Topopah Spring welded tuff unit, the unsaturated Calico Hills nonwelded tuff unit, and the saturated tuff aquifer. Fifty-eight processes and events that might affect such a repository were reviewed. Eighty-three different sequences were identified by which these processes and events could lead to failure of one or more barriers. Sequences which had similar consequences were grouped, yielding 17 categories. The repository system has considerable redundancy; most of the more likely disruptions affect only one or a few barriers. Occurrence of more than one disruption is needed before such disruptions would cause release of radioactivity. Future studies of repository performance must assess the likelihood and consequences of multiple-disruption scenarios to evaluate how well the repository meets performance standards

The international INTRAVAL project. Phase 2, Summary report

International Nuclear Information System (INIS)

Larsson, A.; Pers, K.; Skagius, K.; Dverstorp, B.

1997-01-01

The international project INTRAVAL addresses the validation of models of transport of radionuclides through groundwater in the geosphere. Such models are used in the assessment of the long-term safety of radioactive waste disposal systems. The second phase of INTRAVAL, which started in 1990, was concluded at the end of 1993. The objective of Phase 2 was to increase the understanding how various geophysical, geohydrological and geochemical phenomena of importance for radionuclide transport from a repository to the biosphere could be described by mathematical models and to study the model validation process. Summarized results from Phase 2 of the INTRAVAL study are presented in this report. (K.A.)
GIS for the needs of the Radioactive Waste Repository Authority

Directory of Open Access Journals (Sweden)

Jitka Mikšová

2007-06-01

Full Text Available The Radioactive Waste Repository Authority (RAWRA is a state organisation responsible for the management of activities related to the disposal of all existing and future radioactive waste and spent nuclear fuel classed as a waste in Czech Republic. Worldwide, a deep geological repository is considered the highest degree of safety for a nuclear waste disposal. Such a repository has to be built in a stable geological environment ensuring the isolation of the stored radioactive waste from the surrounding environment for a long period of time. The selection of suitable site for the deep geological repository construction is a complicated and long term process. Considering this fact and also in respect to an assumed volume of varied datasets the GIS RAWRA was established to ensure convenient management and availability of data containing spatial information.The system is based on ESRI (ArcInfo including extensions, ArcSDE, ArcIMS, Leica Geosystems (Image Analysis and Microsoft software (MS SQL Server. Resulting datasets from six recommended potentially suitable sites for the location of a geological repository have been incorporated into the geodatabase to date. The necessary analysis was made using ESRI software tools and, in addition, custom applications were developed including the metadata editor, etc. This analysis was carried out with respect to existing geological and non-geological criteria defined for a nuclear waste repository. Finally, all six investigated sites with a total area of 240 km2 were reduced in area, each of them resulting in an area of approximately 10km2 for further detailed characterisation.
Low and medium level radioactive waste repository: risk perception

International Nuclear Information System (INIS)

Aquino, Afonso Rodrigues de; Bueno, Lilian de Oliveira; Vieira, Martha Marques Ferreira; Fonseca, Edvaldo Roberto Paiva da; Bellintani, Sandra Aparecida

2009-01-01

This paper focuses on the risk perception associated to the installation of low and intermediate level radioactive waste (LLRW and ILRW) disposal facilities. The purpose is to give support for the implementation of a repository in Brazil. Public acceptance results from a long term work and trust is vital for the process as it takes long to be conquered but might be shortly lost. Therefore, it is essential to care about the way each step is conducted. The knowledge about the system and the risks, the comprehension about these risks, the commitment with safety, adequate support systems for the project (legislation, involved institutions) and the excellence as a goal to be reached are extremely important parameters. The involvement of all interested parties in the decision-making process is condition for a successful and publicly acceptable implementation of such project. The steps for public acceptance of a repository are summarized as follow: Risk perception: to verify how the local population understand and feel the installation of a repository in the region. Media observatory: to continuously follow the news reaching the region where the repository will be installed, including different media. Local population social/economical/cultural profile identification: to determine the local population social/economical/cultural profile; to conduct a survey to know their expectations, allowing the proposal of compensation and incentives to fully account for their expectations. Finally, the philosophy governing this Project is: on doubt, the public must be heard and only after this public hearing the policies concerning the project shall be formulated. (author)
Low and medium level radioactive waste repository: risk perception

Energy Technology Data Exchange (ETDEWEB)

Aquino, Afonso Rodrigues de; Bueno, Lilian de Oliveira; Vieira, Martha Marques Ferreira; Fonseca, Edvaldo Roberto Paiva da; Bellintani, Sandra Aparecida [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: araquino@ipen.br, e-mail: lbueno@ipen.br, e-mail: mmvieira@ipen.br, e-mail: efonseca@ipen.br, e-mail: sbellint@ipen.br

2009-07-01

This paper focuses on the risk perception associated to the installation of low and intermediate level radioactive waste (LLRW and ILRW) disposal facilities. The purpose is to give support for the implementation of a repository in Brazil. Public acceptance results from a long term work and trust is vital for the process as it takes long to be conquered but might be shortly lost. Therefore, it is essential to care about the way each step is conducted. The knowledge about the system and the risks, the comprehension about these risks, the commitment with safety, adequate support systems for the project (legislation, involved institutions) and the excellence as a goal to be reached are extremely important parameters. The involvement of all interested parties in the decision-making process is condition for a successful and publicly acceptable implementation of such project. The steps for public acceptance of a repository are summarized as follow: Risk perception: to verify how the local population understand and feel the installation of a repository in the region. Media observatory: to continuously follow the news reaching the region where the repository will be installed, including different media. Local population social/economical/cultural profile identification: to determine the local population social/economical/cultural profile; to conduct a survey to know their expectations, allowing the proposal of compensation and incentives to fully account for their expectations. Finally, the philosophy governing this Project is: on doubt, the public must be heard and only after this public hearing the policies concerning the project shall be formulated. (author)
Review of Quality Assurance in SKB's Repository Research Experiments

Energy Technology Data Exchange (ETDEWEB)

Hicks, T.W. [Galson Sciences Ltd, 5 Grosvenor House, Melton Road, Oakham(United Kingdom)

2007-01-15

SKB is preparing licence applications for a spent nuclear fuel encapsulation plant and repository which will be supported by the SR-Site safety report. A separate safety report, SR-Can, has been produced by SKB in preparation for the SR-Site report. SKI is in the process of reviewing the SR-Can safety report. In preparation for this review, and with a view to building confidence in SKB's research activities and understanding SKB's handling of data and other information, SKI has examined SKB's application of QA measures in the management and conduct of repository research and development projects that support the SR-Can safety assessment. These preliminary investigations will serve to support the preparation of more detailed quality and technical audits of SKB's repository safety assessment after the submission of a licence application. SKI's approach to this QA review is based on the consideration of quality-affecting aspects of a selection of SKB's research and development activities. As part of this review, SKI identified the need to examine quality-related aspects of some of the many experiments and investigations that form part of SKB's repository research programme. This report presents the findings of such a review, focusing on experiments concerned with the properties and performance of the engineered barrier system. First, in order to establish a broad understanding of QA requirements for repository scientific investigations, QA procedures implemented in the management of research and development activities for the low-level radioactive waste repository near Drigg in the UK and the Waste Isolation Pilot Plant and Yucca Mountain repository projects in the US were studied. The QA procedures for experiments and tests undertaken in these projects were compared with those implemented by SKB. Key findings are: QA programmes have been implemented for each repository development programme in response to regulatory requirements
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)
Electronic repository and standardization of processes and electronic documents in transport

Directory of Open Access Journals (Sweden)

Tomasz DĘBICKI

2007-01-01

Full Text Available The article refers to the idea of the use of electronic repository to store standardised scheme of processes between a Logistics Service Provider and its business partners. Application of repository for automatic or semi-automatic configuration of interoperability in electronic data interchange between information systems of differentcompanies based on transport (road, rail, sea and combined related processes. Standardisation includes processes, scheme of cooperation and related to them, electronic messages.
Concepts and examples of safety analyses for radioactive waste repositories in continental geological formations

International Nuclear Information System (INIS)

1983-01-01

This document is addressed to authorities and specialists responsible for or involved in planning, performing and/or reviewing safety assessments of underground radioactive waste repositories. It is a companion to a general introductory document on the subject ''Safety Assessment for the Underground Disposal of Radioactive Wastes'', IAEA Safety Series No. 56, 1981, and reference to this earlier document will facilitate the reader's understanding of the present report. Since examples of safety analyses are summarized here, it is hoped that this document will contribute to providing a basis for a common understanding among authorities and specialists concerned with the numerous studies involving a variety of scientific disciplines. While providing technical information, this document is also intended to stimulate further international discussion. The purposes of this report are: a) to identify the factors to be taken into account in radiological safety analyses of deep geological repositories, indicating as far as possible their relative importance during the various phases of system development; b) to show how these factors have been analysed in various safety assessment studies; and c) to comment on the merits of the selected and alternative approaches
Concepts and examples of safety analyses for radioactive waste repositories in continental geological formations

Energy Technology Data Exchange (ETDEWEB)

1983-01-01

This document is addressed to authorities and specialists responsible for or involved in planning, performing and/or reviewing safety assessments of underground radioactive waste repositories. It is a companion to a general introductory document on the subject ''Safety Assessment for the Underground Disposal of Radioactive Wastes'', IAEA Safety Series No. 56, 1981, and reference to this earlier document will facilitate the reader's understanding of the present report. Since examples of safety analyses are summarized here, it is hoped that this document will contribute to providing a basis for a common understanding among authorities and specialists concerned with the numerous studies involving a variety of scientific disciplines. While providing technical information, this document is also intended to stimulate further international discussion. The purposes of this report are: a) to identify the factors to be taken into account in radiological safety analyses of deep geological repositories, indicating as far as possible their relative importance during the various phases of system development; b) to show how these factors have been analysed in various safety assessment studies; and c) to comment on the merits of the selected and alternative approaches.
Designing Learning Object Repositories as Systems for Managing Educational Communities Knowledge

Science.gov (United States)

Sampson, Demetrios G.; Zervas, Panagiotis

2013-01-01

Over the past years, a number of international initiatives that recognize the importance of sharing and reusing digital educational resources among educational communities through the use of Learning Object Repositories (LORs) have emerged. Typically, these initiatives focus on collecting digital educational resources that are offered by their…
Hydrological and hydrogeological effects of an open repository in Forsmark. Final MIKE SHE flow modelling results for the Environmental Impact Assessment

International Nuclear Information System (INIS)

Maartensson, Erik; Gustafsson, Lars-Goeran

2010-07-01

This report presents methodology and modelling results concerning a deep-rock repository for spent nuclear fuel in Forsmark. Specifically, the modelling tools MIKE SHE, MIKE 11 and MOUSE are used to quantify the groundwater inflow to the repository and associated hydrological and hydrogeological effects during the construction and operation phases. The modelling results presented in the report provide input to the Environmental Impact Assessment (EIA) that will be part of a permit application according to the Environmental Code. Based on an existing MIKE SHE model for Forsmark, the first step of the modelling process was to implement an updated hydrogeological model of the bedrock and to increase the vertical and horizontal extents of the model domain. Other model updates involve the vegetation classification, and implementation of SFR (final repository for short-lived radioactive waste) and the subsurface drainage system at the nearby nuclear power plant. The updated model was calibrated using measured data on groundwater levels in the Quaternary deposits and the bedrock, water levels in lakes, and stream discharges. The calibrated model was then used for simulation of undisturbed conditions (i.e. without the repository) as a reference for modelling results obtained for disturbed conditions (with the repository). The modelling results for undisturbed conditions that are presented in the report closely resemble those of the final MIKE SHE site descriptive modelling (SDM-Site Forsmark). The repository layout was implemented as pipe links (segments) in the modelling tool MOUSE, and the implemented layout was used for the modelling of disturbed conditions. The study uses an updated and verified MIKE SHE-MOUSE coupling routine that is specifically adapted for calculation of groundwater inflow to grouted rock tunnels. The vertical shafts of the repository are implemented in the form of MIKE SHE grid cells with atmospheric pressure. Modelling results for disturbed
Hydrological and hydrogeological effects of an open repository in Forsmark. Final MIKE SHE flow modelling results for the Environmental Impact Assessment

Energy Technology Data Exchange (ETDEWEB)

Maartensson, Erik; Gustafsson, Lars-Goeran (DHI Sverige AB (Sweden))

2010-07-15

This report presents methodology and modelling results concerning a deep-rock repository for spent nuclear fuel in Forsmark. Specifically, the modelling tools MIKE SHE, MIKE 11 and MOUSE are used to quantify the groundwater inflow to the repository and associated hydrological and hydrogeological effects during the construction and operation phases. The modelling results presented in the report provide input to the Environmental Impact Assessment (EIA) that will be part of a permit application according to the Environmental Code. Based on an existing MIKE SHE model for Forsmark, the first step of the modelling process was to implement an updated hydrogeological model of the bedrock and to increase the vertical and horizontal extents of the model domain. Other model updates involve the vegetation classification, and implementation of SFR (final repository for short-lived radioactive waste) and the subsurface drainage system at the nearby nuclear power plant. The updated model was calibrated using measured data on groundwater levels in the Quaternary deposits and the bedrock, water levels in lakes, and stream discharges. The calibrated model was then used for simulation of undisturbed conditions (i.e. without the repository) as a reference for modelling results obtained for disturbed conditions (with the repository). The modelling results for undisturbed conditions that are presented in the report closely resemble those of the final MIKE SHE site descriptive modelling (SDM-Site Forsmark). The repository layout was implemented as pipe links (segments) in the modelling tool MOUSE, and the implemented layout was used for the modelling of disturbed conditions. The study uses an updated and verified MIKE SHE-MOUSE coupling routine that is specifically adapted for calculation of groundwater inflow to grouted rock tunnels. The vertical shafts of the repository are implemented in the form of MIKE SHE grid cells with atmospheric pressure. Modelling results for disturbed
The technical challenge of mechanized excavation for nuclear waste repositories

International Nuclear Information System (INIS)

Smith, A.I.

1991-01-01

This paper presents the historical background of the tunnel boring machine and discusses its integration into the design of a nuclear waste repository. It is essential that the designers of a project utilize the productivity of the system to their advantage. An example would be the construction of a pair of small tunnels instead of a single large diameter access ramp. The pair of tunnels would be more effective in use and less expensive to bore than the single all-purpose tunnel. The designers of an underground nuclear waste repository must recognize the capabilities of the Tunnel Boring Machine system and tailor their design to employ the technological advantages which have been made in recent years
Direct investigations of the immobilization of radionuclides in the alteration phases of spent nuclear fuel. 1998 annual progress report

International Nuclear Information System (INIS)

Burns, P.C.; Finch, R.J.

1998-01-01

'In an oxidizing environment, such as in the proposed repository at Yucca Mountain, rapid alteration rates are expected for spent nuclear fuel. Lab.-scale simulations have repeatedly shown that the dominant alteration products under repository conditions will be uranyl phases. There is an inadequate database that relates to the effects of the alteration products on the release of radionuclides, but this information is essential to provide a radionuclide release estimate. It is likely that many of the radionuclides contained in the fuel will be incorporated into the alteration products that form, potentially with a profound impact on the future mobility of radionuclides in the repository. The authors objective is to characterize the incorporation of radionuclides into alteration products by synthesis of uranyl phases doped with radionuclides, appropriate surrogate elements, or non-radioactive isotopes, followed by detailed phase characterization by diffraction and spectroscopic techniques. The research will permit a more realistic estimate of the release rates of the radionuclides from the near-field environment. This report summarizes work after 8 months of a 3-year project. The objective of investigating radionuclide incorporation in uranyl phases has required the development of synthesis techniques for various uranyl phases that are expected to form under repository conditions. The authors have synthesized and determined the structures of several uranyl phases that are new to science and that may be important alteration products under repository conditions. They have also undertaken the determination and refinement of the crystal structures of various uranyl phases that are likely to form under repository conditions. Other experiments include the investigation of the ion-exchange properties of uranyl phases under repository conditions.'
Monitoring in the post-closure phase. Development of wireless techniques for data transmission from the repository to the surface

International Nuclear Information System (INIS)

Schroeder, Thomas J.; Rosca-Bocancea, Ecaterina; Hart, Jaap

2015-01-01

When the in-situ monitoring in a geological disposal facility is continued during the post-closure phase, monitoring data need to be transmitted wirelessly from the repository to the surface. Wireless data transmission is used today in many applications, but the large attenuation by the geologic medium between the disposal facility and the surface makes the application of high-frequency based techniques impractical. As part of the EURATOM FP-7 project MoDeRn (Monitoring Developments for safe Repository operation and staged closure), NRG has investigated the feasibility of wireless data transmission through an argillaceous host rock (Boom Clay), making use of low frequency magnetic fields. The main focus of the contribution was to analyze and optimize the energy efficiency of this technique. Therefore, a mathematical model description has been developed that allows to estimate the expected signal strength on the earth's surface on basis of the most relevant characteristics of transmitter, receiver and transmission path. The model is used to analyze the complex interactions of different system parameters, and is applied to design an optimized set-up for through-the-earth data transmission and to estimate minimum energy demands for signal transmission. To demonstrate the potentials of this technique, experiments were performed in the 225 m deep underground research facility HADES in Mol, Belgium. Signal propagation and attenuation by the geologic medium between the HADES and the surface has been measured, and the site-specific magnetic background noise at the surface in Mol has been characterized. Based on the results, optimum conditions for signal transmission have been derived and data transmission experiments have been performed. Results show that despite large local interferences on the surface in Mol, wireless data transmission through 225 m of a geological medium is possible. Data transmission rates up to 100 bit/s has been successfully tested. The
Monitoring in the post-closure phase. Development of wireless techniques for data transmission from the repository to the surface

Energy Technology Data Exchange (ETDEWEB)

Schroeder, Thomas J.; Rosca-Bocancea, Ecaterina; Hart, Jaap [Nuclear Research and Consultancy Group (NRG), Petten (Netherlands)

2015-07-01

When the in-situ monitoring in a geological disposal facility is continued during the post-closure phase, monitoring data need to be transmitted wirelessly from the repository to the surface. Wireless data transmission is used today in many applications, but the large attenuation by the geologic medium between the disposal facility and the surface makes the application of high-frequency based techniques impractical. As part of the EURATOM FP-7 project MoDeRn (Monitoring Developments for safe Repository operation and staged closure), NRG has investigated the feasibility of wireless data transmission through an argillaceous host rock (Boom Clay), making use of low frequency magnetic fields. The main focus of the contribution was to analyze and optimize the energy efficiency of this technique. Therefore, a mathematical model description has been developed that allows to estimate the expected signal strength on the earth's surface on basis of the most relevant characteristics of transmitter, receiver and transmission path. The model is used to analyze the complex interactions of different system parameters, and is applied to design an optimized set-up for through-the-earth data transmission and to estimate minimum energy demands for signal transmission. To demonstrate the potentials of this technique, experiments were performed in the 225 m deep underground research facility HADES in Mol, Belgium. Signal propagation and attenuation by the geologic medium between the HADES and the surface has been measured, and the site-specific magnetic background noise at the surface in Mol has been characterized. Based on the results, optimum conditions for signal transmission have been derived and data transmission experiments have been performed. Results show that despite large local interferences on the surface in Mol, wireless data transmission through 225 m of a geological medium is possible. Data transmission rates up to 100 bit/s has been successfully tested. The
Monitoring a repository for high-level radioactive waste in Germany. Possibilities and limits; Ueberwachung eines Endlagers fuer hochradioaktive Abfaelle in Deutschland. Moeglichkeiten und Grenzen

Energy Technology Data Exchange (ETDEWEB)

Jobmann, M.; Haverkamp, B. [DBE Technology GmbH, Peine (Germany); Eilers, G. [Bundesamt fuer Strahlenschutz, Salzgitter (Germany)

2011-11-15

Pursuant to the new BMU safety requirements of September 2010 imposed upon the final storage of radioactive waste generating heat, the operator of a repository in Germany must establish a monitoring program which furnishes relevant measured information during the operations phase and for a defined period of time after closure of the repository. Within the framework of a feasibility study, an assessment basis was established to show in what format information about the status of a closed repository mine could be obtained technically without impairing the safety of barriers, for instance, by cable ducts. As a conceptual design basis, processes and measured quantities relevant to monitoring were attributed to the components of the current safety demonstration concept. For one model variant, monitoring possibilities of these processes were shown on the basis of monitoring modules. Some first experiments are being carried out in European underground laboratories about the use of wireless transmission systems in the repository area. On the basis of those activities, experiments could also be designed in the German exploratory mine of Gorleben in order to examine to what extent information obtained by monitoring could be transmitted in a wireless mode in rock salt formations. As far as the autonomous supply of electricity to measurement systems is concerned, which must be guaranteed on a long-term basis, there is now a possibility of using thermoelectric isotope generators or betavoltaic batteries. (orig.)
Audit of a Scientific Data Center for Certification as a Trustworthy Digital Repository: A Case Study

Science.gov (United States)

Downs, R. R.; Chen, R. S.

2011-12-01

Services that preserve and enable future access to scientific data are necessary to ensure that the data that are being collected today will be available for use by future generations of scientists. Many data centers, archives, and other digital repositories are working to improve their ability to serve as long-term stewards of scientific data. Trust in sustainable data management and preservation capabilities of digital repositories can influence decisions to use these services to deposit or obtain scientific data. Building on the Open Archival Information System (OAIS) Reference Model developed by the Consultative Committee for Space Data Systems (CCSDS) and adopted by the International Organization for Standardization as ISO 14721:2003, new standards are being developed to improve long-term data management processes and documentation. The Draft Information Standard ISO/DIS 16363, "Space data and information transfer systems - Audit and certification of trustworthy digital repositories" offers the potential to evaluate digital repositories objectively in terms of their trustworthiness as long-term stewards of digital resources. In conjunction with this, the CCSDS and ISO are developing another draft standard for the auditing and certification process, ISO/DIS 16919, "Space data and information transfer systems - Requirements for bodies providing audit and certification of candidate trustworthy digital repositories". Six test audits were conducted of scientific data centers and archives in Europe and the United States to test the use of these draft standards and identify potential improvements for the standards and for the participating digital repositories. We present a case study of the test audit conducted on the NASA Socioeconomic Data and Applications Center (SEDAC) and describe the preparation, the audit process, recommendations received, and next steps to obtain certification as a trustworthy digital repository, after approval of the ISO/DIS standards.
Natural geochemical analogues of the near field of high-level nuclear waste repositories

International Nuclear Information System (INIS)

Apps, J.A.

1995-01-01

United States practice has been to design high-level nuclear waste (HLW) geological repositories with waste densities sufficiently high that repository temperatures surrounding the waste will exceed 100 degrees C and could reach 250 degrees C. Basalt and devitrified vitroclastic tuff are among the host rocks considered for waste emplacement. Near-field repository thermal behavior and chemical alteration in such rocks is expected to be similar to that observed in many geothermal systems. Therefore, the predictive modeling required for performance assessment studies of the near field could be validated and calibrated using geothermal systems as natural analogues. Examples are given which demonstrate the need for refinement of the thermodynamic databases used in geochemical modeling of near-field natural analogues and the extent to which present models can predict conditions in geothermal fields
Technical Standards on the Safety Assessment of a HLW Repository in Other Countries

International Nuclear Information System (INIS)

Lee, Sung Ho; Hwang, Yong Soo

2009-01-01

The basic function of HLW disposal system is to prevent excessive radio-nuclides being leaked from the repository in a short time. To do this, many technical standards should be developed and established on the components of disposal system. Safety assessment of a repository is considered as one of technical standards, because it produces quantitative results of the future evolution of a repository based on a reasonably simplified model. In this paper, we investigated other countries' regulations related to safely assessment focused on the assessment period, radiation dose limits and uncertainties of the assessment. Especially, in the investigation process of the USA regulations, the USA regulatory bodies' approach to assessment period and peak dose is worth taking into account in case of a conflict between peak dose from safety assessment and limited value in regulation.

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.
Gas generation and migration analysis for TRU waste disposal system

International Nuclear Information System (INIS)

Ando, Kenichi; Noda, Masaru; Yamamoto, Mikihiko; Mihara, Morihiro

2005-09-01

In TRU waste disposal system, significant quantities of gases may be generated due to metal corrosion, radiolysis effect and microorganism activities. It is therefore recommended that the potential impact of gas generation and migration on TRU waste repository should be evaluated. In this study, gas generation rates were calculated in the repository and gas migration analysis in the disposal system were carried out using two phase flow model with results of gas generation rates. First, the time dependencies of gas generation rate in each TRU waste repositories were evaluated based on amounts of metal, organic matter and radioactivity. Next, the accumulation pressure of gases and expelled pore water volume nuclides in the repository were calculated by TOUGH2 code. After that, the results showed that the increase of gas pressure was the range of 1.3 to 1.4 MPa. In the repository with and without buffer, the rate of expelled pore water was 0.006 - 0.009 m 3 /y and 0.018 - 0.24m 3 /y, respectively. In addition, the radioactive gas migration through the repository and geosphere are evaluated. And re-saturation analysis is also performed to evaluate the initial condition of the system. (author)
Scientific information repository assisting reflectance spectrometry in legal medicine.

Science.gov (United States)

Belenki, Liudmila; Sterzik, Vera; Bohnert, Michael; Zimmermann, Klaus; Liehr, Andreas W

2012-06-01

Reflectance spectrometry is a fast and reliable method for the characterization of human skin if the spectra are analyzed with respect to a physical model describing the optical properties of human skin. For a field study performed at the Institute of Legal Medicine and the Freiburg Materials Research Center of the University of Freiburg, a scientific information repository has been developed, which is a variant of an electronic laboratory notebook and assists in the acquisition, management, and high-throughput analysis of reflectance spectra in heterogeneous research environments. At the core of the repository is a database management system hosting the master data. It is filled with primary data via a graphical user interface (GUI) programmed in Java, which also enables the user to browse the database and access the results of data analysis. The latter is carried out via Matlab, Python, and C programs, which retrieve the primary data from the scientific information repository, perform the analysis, and store the results in the database for further usage.
Special features of nuclear waste repository ventilation system VIS-A-VIS experiences at the Waste Isolation Pilot Plant

International Nuclear Information System (INIS)

Sethi, S.C.

1991-01-01

The paper presents an analysis and discussion of the underground ventilation system at the Waste Isolation Pilot Plant (WIPP). Particular emphasis is placed on specific repository-related requirements and the gradual evolution of engineering designs relative to the WIPP Project scope. The ventilation system for a nuclear waste facility similar to WIPP is designed to provide a suitable environment for personnel and equipment during normal activities. It is also designed to provide confinement and channeling of potential airborne radioactive material in the event of an accidental release. It is desirable to identify and design all parallel activities and the required process equipment prior to completion of the repository mine final design. Such factors as ventilation requirements, drift sizes, bulkhead sizes, and placement are dependent on these items. Mine creep closure properties must be factored into the mine and ventilation equipment design considerations. Effects of natural ventilation pressures deserve due consideration in the design. Mine ventilation requirements are dominated by the diesel equipment to be operated in the underground horizon. WIPP engineers have also found it extremely desirable to have automated real-time monitoring and control for the underground ventilation air. Final testing and balancing of the ventilation system is an extremely important startup requirement. 3 refs., 2 figs
Establishment of IAEA knowledge of integrity of the geological repository boundaries and disposed spent fuel assemblies in the context of the Finnish geological repository. Experts' Group meeting Report on Task JNT/C 1204 of the Member States' Support Programme to IAEA Safeguards

International Nuclear Information System (INIS)

Okko, O.

2004-05-01

The Geological Repository Safeguards Experts Group (Member State Support Programme tasks JNT/C1204 and C1226), agreed that annual meetings should be held to address interface issues between IAEA safeguards and radioactive waste management and to explore the use of safety and operational information to make International Atomic Energy Agency (IAEA) safeguards more effective and efficient for geological repository facilities. It has also been recognised that the safeguards measures for geological repositories are to be developed site-specifically. To address these issues to the planned Olkiluoto repository in Finland a meeting of experts in safety, geological repository operations,and safeguards from 6 States, European Commission, and IAEA was held in Olkiluoto and Rauma, Finland, during September 29 - October 4, 2003. The pre-operational phase of the Olkiluoto repository should be efficiently used by the parties involved in safeguards. The applicability and reliability of the potential new techniques and the efficient practices must be developed and proven before their implementation as safeguards measures to be applied at the subsequent stages of the repository development. The visit to the location of the proposed Olkiluoto repository and neighbouring areas and subsequent presentations enabled the working groups to discuss the various issues with reference to actual site conditions. The working groups were thus able to identify potential measurement and monitoring techniques and research and development requirements for consideration by the Finnish authorities, in addition to making recommendations to the IAEA on planned activities for carrying out before and during the early investigation phase of the proposed Olkiluoto repository. It was understood that all parties shall take good care of the implementation of the planned activities to ensure that proven means, approaches and the required verified information is at hand at the time the projected facility will
Modeling gas migration experiments in repository host rocks for the MEGAS project

International Nuclear Information System (INIS)

Worgan, K.; Impey, M.; Volckaert, G.; DePreter, P.

1993-01-01

In response to concerns over the possibility of hydrogen gas generation within an underground repository for high-level radioactive waste, and its implications for repository safety, a joint European research study (MEGAS) is underway. Its aims are to understand and characterize the behavior of gas migration within an argillacious, host-rock. Laboratory experiments are being carried out by SCK/CEN, BGS and ISMES. SCK/CEN are also conducting in situ experiments at the underground laboratory at Mol, Belgium. Modeling of gas migration is being done in parallel with the experiments, by Intera Information Technologies. A two-phase flow code, TOPAZ, has been developed specifically for this work. In this paper the authors report on the results of some preliminary calculations performed with TOPAZ, in advance of the in situ experiments
Designing shafts for handling high-level radioactive wastes in mined geologic repositories

International Nuclear Information System (INIS)

Hambley, D.F.; Morris, J.R.

1988-01-01

Waste package conceptual designs developed in the United States by the U.S. Department of Energy's Office of Civilian Radioactive Waste Management are the basis for specifying the dimensions and weights of the waste package and transfer cask combinations to be hoisted in the waste handling shafts in mined geologic repositories for high-level radioactive waste. The hoist, conveyance, counterweight, and hoist ropes are then sized. Also taken into consideration are overwind and underwind arrestors and safety features required by the U.S. Nuclear Regulatory Commission. Other design features such as braking systems, chairing system design, and hoisting speed are considered in specifying waste hoisting system parameters for example repository sites
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...
Rhode Island crystalline repository project: Technical progress report, 1984-1986

International Nuclear Information System (INIS)

1986-01-01

A Nuclear Waste Fund established by the Nuclear Waste Policy Act of 1982 provided financial support to the State of Rhode Island for its participation in the high-level radioactive waste repository siting program. In 1984, the Office of the Governor set up a multidisciplinary Project Review Team consisting of staff from three State agencies and the University of Rhode Island. Members of the Review Team attended several meetings throughout the reporting period to voice their concerns about siting directly to the US Department of Energy (DOE). Written comments were also submitted on draft plans and reports. Many of Rhode Island's recommendations in these comments were later adopted. In May, 1986, Secretary of Energy John Herrington announced the suspension of the crystalline repository siting program. The remainder of the year was spent monitoring litigation challenging that decision and pending legislation. Administrative phase-down of the program was essentially complete by the close of the calendar year
Phase Control in Nonlinear Systems

Science.gov (United States)

Zambrano, Samuel; Seoane, Jesús M.; Mariño, Inés P.; Sanjuán, Miguel A. F.; Meucci, Riccardo

The following sections are included: * Introduction * Phase Control of Chaos * Description of the model * Numerical exploration of phase control of chaos * Experimental evidence of phase control of chaos * Phase Control of Intermittency in Dynamical Systems * Crisis-induced intermittency and its control * Experimental setup and implementation of the phase control scheme * Phase control of the laser in the pre-crisis regime * Phase control of the intermittency after the crisis * Phase control of the intermittency in the quadratic map * Phase Control of Escapes in Open Dynamical Systems * Control of open dynamical systems * Model description * Numerical simulations and heuristic arguments * Experimental implementation in an electronic circuit * Conclusions and Discussions * Acknowledgments * References
Portal and repository for sharing mathematical learning objects

NARCIS (Netherlands)

Zanden, van der A.H.W.; Cuypers, H.; Luca, J.; Weippl, E.R.

2008-01-01

Now that Virtual Learning Environments are common within higher education in the Netherlands it is time to work with online validated informational resources. Technologies such as repositories are the systems to manage learning content but are most inconvenient in use. The national project NKBW aims
A Miniature Data Repository on a Raspberry Pi

NARCIS (Netherlands)

Samourkasidis, Argyrios; Athanasiadis, Ioannis N.

2017-01-01

This work demonstrates a low-cost, miniature data repository proof-of-concept. Such a system needs to be resilient to power and network failures, and expose adequate processing power for persistent, long-term storage. Additional services are required for interoperable data sharing and visualization.
Monitoring of IL/HL, LL waste repository in a clay formation: objectives, technical know-how, implementation strategy

International Nuclear Information System (INIS)

Grevoz, Arnaud; Mayer, Stefan; Dubois, Jean-Philippe

2005-01-01

In France, with regards to the monitoring of a reversible repository in a clay host formation, Andra utilised international references as input to develop its own strategy and program, e.g. IAEA TECDOC 1208 and DS-154 2004, NEA 2001 (reversibility and retrievability), EUR 21025 EN. Additionally, the French safety rule RFSIII.2.f, which aims to provide guidelines but is not a regulatory requirement, deals with 'general provisions concerning explorations'. The RFSIII.2.f distinguishes between exploration conducted from the surface, investigations to be carried out in the Underground Research Laboratory (URL) and monitoring of changes in the site while the repository is in operation. The monitoring programme responds to the three main motivations: 1. the respect of operational safety and regulatory requirements; 2. the acquisition of data to improve the understanding of processes and parameters underlying the long term safety assessment; and 3. reversibility. In that respect, Andra defines monitoring terminology by distinguishing two main activities: (i) observation (for scientific and engineering understanding and reversibility) and (ii) surveillance (related to operational and long term safety). Surveillance to contribute to the operational safety of a repository, e.g. surveillance of drift stability, fire and radiological hazards, is in line with other classical and nuclear operational safety principles and practices. Surveillance to contribute to long term safety can provide input to periodic re-evaluations of the safety analysis of a geologic repository, with a view of improving system understanding and confirming data in situ, prior to final closure of the repository. As such, it is in line with the usual regulatory guidance for Nuclear Power Plant (NPP) facilities. While it will not provide direct data on the long-term evolution of the system, it may provide some data, for example related to initial conditions or to an early transient phase, for
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
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
Groundwater flow modelling of the excavation and operational phases - Laxemar

Energy Technology Data Exchange (ETDEWEB)

Svensson, Urban (Computer-aided Fluid Engineering AB, Lyckeby (Sweden)); Rhen, Ingvar (SWECO Environment AB, Falun (Sweden))

2010-12-15

As a part of the license application 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 reported here presents calculated inflow rates, drawdown of the groundwater table and upconing of deep saline water for different levels of grouting efficiency during the excavation and operational phases of a final repository at Laxemar. The inflow calculations were accompanied by a sensitivity study, which among other matters handled the impact of different deposition hole rejection criteria. The report also presents tentative modelling results for the duration of the saturation phase, which starts once the used parts of the repository are being backfilled
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
Spent fuel performance in geologic repository environments

International Nuclear Information System (INIS)

Bradley, D.J.

1985-10-01

The performance assessment of the waste package is a current area of study in the United States program to develop a geologic repository for nuclear waste isolation. The waste package is presently envisioned as the waste form and its surrounding containers and possibly a packing material composed of crushed host rock or mixtures of that rock with clays. This waste package is tied to performance criteria set forth in recent legislation. It is the goal of the Civilian Radioactive Waste Management Program to obtain the necessary information on the waste package, in several geologic environments, to show that the waste package provides reasonable assurance of meeting established performance criteria. This paper discusses the United States program directed toward managing high-level radioactive waste, with emphasis on the current effort to define the behavior of irradiated spent fuel in repository groundwaters. Current studies are directed toward understanding the rate and nature (such as valence state, colloid form if any, solid phase controlling solubility) of radionuclide release from the spent fuel. Due to the strong interactive effect of radiation, thermal fields, and waste package components on this release, current spent fuel studies are being conducted primarily in the presence of waste package components over a wide range of potential environments
Office of Geologic Repositories issues hierarchy for a mined geologic disposal system

International Nuclear Information System (INIS)

1987-08-01

The Nuclear Regulatory Commission (NRC) has indicated that the identification of the issues that must be resolved to complete licensing assessments of site and design suitability is an important step in the licensing process. The issues hierarchy developed by the Office of Geologic Repositories (OGR) for the mined geologic disposal system (MGDS) are based on the issues-hierarchy concept presented in the Mission Plan. Specific questions are encompassed by the general issue statements in the OGR issues hierarchy. The OGR issues hierarchy is limited to the issues related to the siting and licensing requirements of applicable federal regulations and does not address the requirements of other regulations, functional or operating requirements for the MGDS, or requirements for the integration and the design/operational efficiency of the MGDS. 4 figs
NASA Life Sciences Data Repositories: Tools for Retrospective Analysis and Future Planning

Science.gov (United States)

Thomas, D.; Wear, M.; VanBaalen, M.; Lee, L.; Fitts, M.

2011-01-01

As NASA transitions from the Space Shuttle era into the next phase of space exploration, the need to ensure the capture, analysis, and application of its research and medical data is of greater urgency than at any other previous time. In this era of limited resources and challenging schedules, the Human Research Program (HRP) based at NASA s Johnson Space Center (JSC) recognizes the need to extract the greatest possible amount of information from the data already captured, as well as focus current and future research funding on addressing the HRP goal to provide human health and performance countermeasures, knowledge, technologies, and tools to enable safe, reliable, and productive human space exploration. To this end, the Science Management Office and the Medical Informatics and Health Care Systems Branch within the HRP and the Space Medicine Division have been working to make both research data and clinical data more accessible to the user community. The Life Sciences Data Archive (LSDA), the research repository housing data and information regarding the physiologic effects of microgravity, and the Lifetime Surveillance of Astronaut Health (LSAH-R), the clinical repository housing astronaut data, have joined forces to achieve this goal. The task of both repositories is to acquire, preserve, and distribute data and information both within the NASA community and to the science community at large. This is accomplished via the LSDA s public website (http://lsda.jsc.nasa.gov), which allows access to experiment descriptions including hardware, datasets, key personnel, mission descriptions and a mechanism for researchers to request additional data, research and clinical, that is not accessible from the public website. This will result in making the work of NASA and its partners available to the wider sciences community, both domestic and international. The desired outcome is the use of these data for knowledge discovery, retrospective analysis, and planning of future

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