WorldWideScience

Sample records for geological repository development

  1. The development of safeguards for geological repositories

    International Nuclear Information System (INIS)

    Van der Meer, K.

    2009-01-01

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

  2. Current Status of Deep Geological Repository Development

    International Nuclear Information System (INIS)

    Budnitz, R J

    2005-01-01

    This talk provided an overview of the current status of deep-geological-repository development worldwide. Its principal observation is that a broad consensus exists internationally that deep-geological disposal is the only long-term solution for disposition of highly radioactive nuclear waste. Also, it is now clear that the institutional and political aspects are as important as the technical aspects in achieving overall progress. Different nations have taken different approaches to overall management of their highly radioactive wastes. Some have begun active programs to develop a deep repository for permanent disposal: the most active such programs are in the United States, Sweden, and Finland. Other countries (including France and Russia) are still deciding on whether to proceed quickly to develop such a repository, while still others (including the UK, China, Japan) have affirmatively decided to delay repository development for a long time, typically for a generation of two. In recent years, a major conclusion has been reached around the world that there is very high confidence that deep repositories can be built, operated, and closed safely and can meet whatever safety requirements are imposed by the regulatory agencies. This confidence, which has emerged in the last few years, is based on extensive work around the world in understanding how repositories behave, including both the engineering aspects and the natural-setting aspects, and how they interact together. The construction of repositories is now understood to be technically feasible, and no major barriers have been identified that would stand in the way of a successful project. Another major conclusion around the world is that the overall cost of a deep repository is not as high as some had predicted or feared. While the actual cost will not be known in detail until the costs are incurred, the general consensus is that the total life-cycle cost will not exceed a few percent of the value of the

  3. PROCESS FOR LICENSE APPLICATION DEVELOPMENT FOR THE GEOLOGIC REPOSITORY

    International Nuclear Information System (INIS)

    DOUGLAS M. FRANKS AND NORMAN C. HENDERSON

    1997-01-01

    The Department of Energy (DOE), specifically the Office of Civilian Radioactive Waste Management (OCRWM) has been charged by the U.S. Congress, through the Nuclear Waste Policy Act (NWPA), with the responsibility for obtaining a license to develop a geologic repository. The NRC is the licensing authority for geologic disposal, and its regulations pertinent to construction authorization and license application are specified in 10 CFR Part 60, Disposal of High-Level Radioactive Wastes in Geologic Repositories, (section)60.21ff and (section)60.31ff. This paper discusses the process the Yucca Mountain Site Site Characterization Project (YMP) will use to identify and apply regulatory and industry guidance to development of the license application (LA) for a geologic repository at Yucca Mountain, Nevada. This guidance will be implemented by the ''Technical Guidance Document for Preparation of the License Application'' (TGD), currently in development

  4. Process for license application development for the geologic repository

    International Nuclear Information System (INIS)

    Franks, D.M.; Henderson, N.C.

    1998-01-01

    The Department of Energy (DOE), specifically the Office of Civilian Radioactive Waste Management (OCRWM) has been charged by the US Congress, through the Nuclear Waste Policy Act (NWPA), with the responsibility for obtaining a license to develop a geologic repository. The NRC is the licensing authority for geologic disposal, and its regulations pertinent to construction authorization and license application are specified in 10 CFR Part 60, Disposal of High-Level Radioactive Wastes in Geologic Repositories, section 60.21ff and section 60.31ff. This paper discusses the process the Yucca Mountain Site Characterization Project (YMP) will use to identify and apply regulatory and industry guidance to development of the license application (LA) for a geologic repository at Yucca Mountain, Nevada. This guidance will be implemented by the Technical Guidance Document for Preparation of the License Application (TGD), currently in development

  5. Safeguards for geological repositories

    International Nuclear Information System (INIS)

    Fattah, A.

    2000-01-01

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

  6. 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)

  7. Status and development of deep geological repository in Slovak republic from geological point of view

    Directory of Open Access Journals (Sweden)

    Jozef Franzen

    2007-01-01

    Full Text Available During the operation of Slovak NPPs, production of approximately 2,300 metric tons of spent fuel expressed as heavy metal (18,654 spent fuel assemblies is expected. In addition, about 5000 metric tons of radioactive waste unfit for near surface repository at Mochovce and destined for a deep geological disposal. The safe and long-term solution of back-end fuel cycle is so highly required.One of the most favorable solutions is Deep Geological Repository (DGR. The site for a DGR, along with repository design and the engineered barrier system must ensure long-term safety of the disposal system.A preliminary set of site-selection criteria for a DGR was proposed in Slovakia, based on worldwide experience and consistent with IAEA recommendations. Main groups of criteria are: 1 geological and tectonic stability of prospective sites; 2 appropriate characteristics of host rock (lithological homogeneity, suitable hydrogeological and geochemical conditions, favourable geotechnical setting, absence of mineral resources, etc.; 3 conflict of interests (natural resources, natural and cultural heritage, protected resources of thermal waters, etc..Based on the previous geological investigations, three distinct areas (five localities were determined as the most prospective sites for construction of a DGR so far. Three of them are built by granitoids rock (Tribeč Mts., Veporske vrchy Mts. and Stolicke vrchy Mts., other consist of sedimentary rock formations (Cerova vrchovina Upland and Rimavska kotlina Basin. Objective for the next investigation stage is to perform more detailed geological characterization of the prospective sites.

  8. Development of an international safeguards approach to the final disposal of spent fuel in geological repositories

    International Nuclear Information System (INIS)

    Murphey, W.M.; Moran, B.W.; Fattah, A.

    1996-01-01

    The International Atomic Energy Agency (IAEA) is currently pursuing development of an international safeguards approach for the final disposal of spent fuel in geological repositories through consultants meetings and through the Program for Development of Safeguards for Final Disposal of Spent Fuel in Geological Repositories (SAGOR). The consultants meetings provide policy guidance to IAEA; SAGOR recommends effective approaches that can be efficiently implemented by IAEA. The SAGOR program, which is a collaboration of eight Member State Support Programs (MSSPs), was initiated in July 1994 and has identified 15 activities in each of three areas (i.e. conditioning facilities, active repositories, and closed repositories) that must be performed to ensure an efficient, yet effective safeguards approach. Two consultants meetings have been held: the first in May 1991 and the last in November 1995. For nuclear materials emplaced in a geological repository, the safeguards objectives were defined to be (1) to detect the diversion of spent fuel, whether concealed or unconcealed, from the repository and (2) to detect undeclared activities of safeguards concern (e.g., tunneling, underground reprocessing, or substitution in containers)

  9. Integrated safety case development for deep geological repositories

    International Nuclear Information System (INIS)

    Kawamura, Hideki; McKinley, Ian G.

    2008-01-01

    The paper will illustrate an 'integrated safety case', which involves combining both pre-closure and post-closure safety arguments from the point of view of a repository implementer, who must also ensure that projects are practical, acceptable and economic. The post-closure safety case is based on the performance of a number of barriers, which are established during construction, operation and closure. Such barriers must be confirmed using quality assured methods, supported, as required, by inspection and monitoring. The requirement for integrated assessment means that even the final process to end institutional control and transfer any liabilities from the implementer needs to be considered at present, even though this will undoubtedly be refined and tailored to the site characteristics over the many decades that will pass before this occurs. To illustrate the practical application of this approach, assessment of variants for remote-handled emplacement of the EBS for disposal of HLW in Japan will be discussed. (author)

  10. 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

  11. Confidence in the long-term safety of deep geological repositories. Its development and communication

    International Nuclear Information System (INIS)

    1999-01-01

    The technical aspects of confidence have been the subject of considerable debate, especially the concept of model validation. The safety case that is provided at a particular stage in the planning, construction, operation or closure of a deep geological repository is a part of a broader decision basis that guides the repository-development process. The basic steps for deriving the safety case at various stages of repository development involve: a safety assessment; and the documentation of the safety assessment, a statement of confidence in the safety indicated by the assessment, and the confirmation of the appropriateness of the safety strategy. The approaches to establish confidence in the evaluation of safety should aim to ensure that the decisions taken within the incremental process of repository development are well-founded. Various aspects of confidence in the evaluation of safety, and their integration within a safety case, are presented in detail in the present report. When communicating confidence in the findings of a safety assessment, clarity in the communication of concepts is always required. Consistent with this requirement, key concepts are specifically defined in the main text of the report. (R.P.)

  12. NWTS program criteria for mined geologic disposal of nuclear waste: repository performance and development criteria. Public draft

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-07-01

    This document, DOE/NWTS-33(3) is one of a series of documents to establish the National Waste Terminal Storage (NWTS) program criteria for mined geologic disposal of high-level radioactive waste. For both repository performance and repository development it delineates the criteria for design performance, radiological safety, mining safety, long-term containment and isolation, operations, and decommissioning. The US Department of Energy will use these criteria to guide the development of repositories to assist in achieving performance and will reevaluate their use when the US Nuclear Regulatory Commission issues radioactive waste repository rules.

  13. NWTS program criteria for mined geologic disposal of nuclear waste: repository performance and development criteria. Public draft

    International Nuclear Information System (INIS)

    1982-07-01

    This document, DOE/NWTS-33(3) is one of a series of documents to establish the National Waste Terminal Storage (NWTS) program criteria for mined geologic disposal of high-level radioactive waste. For both repository performance and repository development it delineates the criteria for design performance, radiological safety, mining safety, long-term containment and isolation, operations, and decommissioning. The US Department of Energy will use these criteria to guide the development of repositories to assist in achieving performance and will reevaluate their use when the US Nuclear Regulatory Commission issues radioactive waste repository rules

  14. Development of Spherical Near Field Model for Geological Radioactive Waste Repository

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. Y.; Lee, K. J.; Chang, S. H. [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Lee, K. J.; Chang, S. H. [Khalifa Univ. of Science/Technology and Research, Abu Dhabi (United Arab Emirates)

    2012-03-15

    Modeling for geological radioactive waste repository can be divided into 3 parts. They are near field modeling related to engineered barrier, far field modeling related to natural barrier and biosphere modeling. In order to make the general application for safety assessment of geological waste repository, spherical geometry near field model has been developed. This model can be used quite extensively when users calculate equivalent spherical geometry for specific engineered barrier like equivalent waste radius, equivalent barrier radius and etc. Only diffusion was considered for general purpose but advection part can be updated. Goldsim and Goldsim Radionuclide Transport (RT) module were chosen and used as developing tool for the flexible modeling. Developer can freely make their own model with developer friendly graphic interface by using Goldsim. Furthermore, model with user friendly graphic interface can be developed by using Goldsim Dashboard Authoring module. The model has been validated by comparing the result with that of another model, inserting similar inputs and conditions. The model has been proved to be reasonably operating from the comparison result by validation process. Cylindrical model can be developed as a further work based on the knowledge and experience from this research.

  15. Development of Spherical Near Field Model for Geological Radioactive Waste Repository

    International Nuclear Information System (INIS)

    Kim, S. Y.; Lee, K. J.; Chang, S. H.; Lee, K. J.; Chang, S. H.

    2012-01-01

    Modeling for geological radioactive waste repository can be divided into 3 parts. They are near field modeling related to engineered barrier, far field modeling related to natural barrier and biosphere modeling. In order to make the general application for safety assessment of geological waste repository, spherical geometry near field model has been developed. This model can be used quite extensively when users calculate equivalent spherical geometry for specific engineered barrier like equivalent waste radius, equivalent barrier radius and etc. Only diffusion was considered for general purpose but advection part can be updated. Goldsim and Goldsim Radionuclide Transport (RT) module were chosen and used as developing tool for the flexible modeling. Developer can freely make their own model with developer friendly graphic interface by using Goldsim. Furthermore, model with user friendly graphic interface can be developed by using Goldsim Dashboard Authoring module. The model has been validated by comparing the result with that of another model, inserting similar inputs and conditions. The model has been proved to be reasonably operating from the comparison result by validation process. Cylindrical model can be developed as a further work based on the knowledge and experience from this research

  16. 10 CFR 51.67 - Environmental information concerning geologic repositories.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Environmental information concerning geologic repositories... information concerning geologic repositories. (a) In lieu of an environmental report, the Department of Energy... connection with any geologic repository developed under Subtitle A of Title I, or under Title IV, of the...

  17. New developments in measurements technology relevant to the studies of deep geological repositories in bedded salt

    International Nuclear Information System (INIS)

    Mao, N.; Ramirez, A.L.

    1980-01-01

    This report presents new developments in measurement technology relevant to the studies of deep geological repositories for nuclear waste disposal during all phases of development, i.e., site selection, site characterization, construction, operation, and decommission. Emphasis has been placed on geophysics and geotechnics with special attention to those techniques applicable to bedded salt. The techniques are grouped into sections as follows: tectonic environment, state of stress, subsurface structures, fractures, stress changes, deformation, thermal properties, fluid transport properties, and other approaches. Several areas that merit further research and developments are identified. These areas are: in situ thermal measurement techniques, fracture detection and characterization, in situ stress measurements, and creep behavior. The available instrumentations should generally be improved to have better resolution and accuracy, enhanced instrument survivability, and reliability for extended time periods in a hostile environment

  18. New developments in measurements technology relevant to the studies of deep geological repositories in bedded salt

    Science.gov (United States)

    Mao, N. H.; Ramirez, A. L.

    1980-10-01

    Developments in measurement technology are presented which are relevant to the studies of deep geological repositories for nuclear waste disposal during all phases of development, i.e., site selection, site characterization, construction, operation, and decommission. Emphasis was placed on geophysics and geotechnics with special attention to those techniques applicable to bedded salt. The techniques are grouped into sections as follows: tectonic environment, state of stress, subsurface structures, fractures, stress changes, deformation, thermal properties, fluid transport properties, and other approaches. Several areas that merit further research and developments are identified. These areas are: in situ thermal measurement techniques, fracture detection and characterization, in situ stress measurements, and creep behavior. The available instrumentations should generally be improved to have better resolution and accuracy, enhanced instrument survivability, and reliability for extended time periods in a hostile environment.

  19. New developments in measurement technology relevant to the studies of deep geological repositories in domed salt and basalt

    International Nuclear Information System (INIS)

    Ramirez, A.L.; Mao, N.H.

    1980-01-01

    This report briefly describes recent geophysical and geotechnical instrumentation developments relevant to the studies of deep geologic repositories. Special emphasis has been placed on techniques that appear to minimize measurement problems associated with repositories constructed in basalt or domed salt. Included in the listing are existing measurement capabilities and deficiencies that have been identified by a few authors and instrumentation workshops that have assessed the capabilities of existing instrumentation with respect to repository applications. These deficiencies have been compared with the reported advantages and limitations of the new developments described. Based on these comparisons, areas that merit further research and development have been identified. The report is based on a thorough literature review and on discussions with several instrumentation specialists involved in instrumentation development

  20. Source-book of International Activities Related to the Development of Safety Cases for Deep Geological Repositories

    International Nuclear Information System (INIS)

    2017-01-01

    All national radioactive waste management authorities recognise today that a robust safety case is essential in developing disposal facilities for radioactive waste. To improve the robustness of the safety case for the development of a deep geological repository, a wide variety of activities have been carried out by national programs and international organisations over the past years. The Nuclear Energy Agency, since first introducing the modern concept of the 'safety case', has continued to monitor major developments in safety case activities at the international level. This Source-book summarises the activities being undertaken by the Nuclear Energy Agency, the European Commission and the International Atomic Energy Agency concerning the safety case for the operational and post-closure phases of geological repositories for radioactive waste that ranges from low-level to high-level waste and for spent fuel. In doing so, it highlights important differences in focus among the three organisations

  1. Andra's geologic repository monitoring strategy

    International Nuclear Information System (INIS)

    Buschaert, S.; Lesoille, S.; Bertrand, J.; Landais, P.

    2012-01-01

    Document available in extended abstract form only. After having concluded a feasibility study of deep geological disposal for high-level and long-lived radioactive waste in 2005, Andra was charged by the Planning Act no. 2006-739 to design and create an industrial site for geological disposal called Cigeo which must be reversible for at least a century-long period. The French Safety Guide recommends that Andra develop a monitoring program to be implemented at repository construction and conducted until closure, and possibly after closure, with the aim to confirming prior expectations and enhancing knowledge of relevant processes. This abstract focuses on underground structure monitoring. The monitoring system is based on a combination of in-situ instrumentation and nondestructive methods to obtain the required level of reliable performance. To optimize the device distribution, we take into account both the repetitive design of disposal cells and the homogeneity of the rock properties. This resulted in distinguishing pilot disposal cells that are highly instrumented and standard disposal cells where the instrumentation density could be reduced; monitoring will rely mostly on robotic nondestructive evaluations. If monitoring technologies do not comply with all monitoring objectives, real withdrawal tests of high level wastes in some pilot disposal cells are also planned to provide the possibility of carrying out visual inspection, destructive analyses and samplings on construction materials. Such cells are planned to be dismantled because of the potential disturbance of their component performances from the testing process. Based on this overall strategy, Andra has analyzed the technical requirements that must be met by its monitoring equipment. First, these must be able to provide information on key THMCR (Thermal- Hydraulic-Mechanical-Chemical and Radiological) processes, to provide a three-dimensional image of a disposal component's behavior and thus to understand

  2. Muon Tomography for Geological Repositories.

    Science.gov (United States)

    Woodward, D.; Kudryavtsev, V.; Gluyas, J.; Clark, S. J.; Thompson, L. F.; Klinger, J.; Spooner, N. J.; Blackwell, T. B.; Pal, S.; Lincoln, D. L.; Paling, S. M.; Mitchell, C. N.; Benton, C.; Coleman, M. L.; Telfer, S.; Cole, A.; Nolan, S.; Chadwick, P.

    2015-12-01

    Cosmic-ray muons are subatomic particles produced in the upper atmosphere in collisions of primary cosmic rays with atoms in air. Due to their high penetrating power these muons can be used to image the content (primarily density) of matter they pass through. They have already been used to image the structure of pyramids, volcanoes and other objects. Their applications can be extended to investigating the structure of, and monitoring changes in geological formations and repositories, in particular deep subsurface sites with stored CO2. Current methods of monitoring subsurface CO2, such as repeat seismic surveys, are episodic and require highly skilled personnel to operate. Our simulations based on simplified models have previously shown that muon tomography could be used to continuously monitor CO2 injection and migration and complement existing technologies. Here we present a simulation of the monitoring of CO2 plume evolution in a geological reservoir using muon tomography. The stratigraphy in the vicinity of the reservoir is modelled using geological data, and a numerical fluid flow model is used to describe the time evolution of the CO2 plume. A planar detection region with a surface area of 1000 m2 is considered, at a vertical depth of 776 m below the seabed. We find that one year of constant CO2 injection leads to changes in the column density of about 1%, and that the CO2 plume is already resolvable with an exposure time of less than 50 days. The attached figure show a map of CO2 plume in angular coordinates as reconstructed from observed muons. In parallel with simulation efforts, a small prototype muon detector has been designed, built and tested in a deep subsurface laboratory. Initial calibrations of the detector have shown that it can reach the required angular resolution for muon detection. Stable operation in a small borehole within a few months has been demonstrated.

  3. Geologic environments for nuclear waste repositories

    Directory of Open Access Journals (Sweden)

    Paleologos Evan K.

    2017-01-01

    Full Text Available High-level radioactive waste (HLW results from spent reactor fuel and reprocessed nuclear material. Since 1957 the scientific consensus is that deep geologic disposal constitutes the safest means for isolating HLW for long timescales. Nuclear power is becoming significant for the Arab Gulf countries as a way to diversify energy sources and drive economic developments. Hence, it is of interest to the UAE to examine the geologic environments currently considered internationally to guide site selection. Sweden and Finland are proceeding with deep underground repositories mined in bedrock at depths of 500m, and 400m, respectively. Equally, Canada’s proposals are deep burial in the plutonic rock masses of the Canadian Shield. Denmark and Switzerland are considering disposal of their relative small quantities of HLW into crystalline basement rocks through boreholes at depths of 5,000m. In USA, the potential repository at Yucca Mountain, Nevada lies at a depth of 300m in unsaturated layers of welded volcanic tuffs. Disposal of low and intermediate-level radioactive wastes, as well as the German HLW repository favour structurally-sound layered salt stata and domes. Our article provides a comprehensive review of the current concepts regarding HLW disposal together with some preliminary analysis of potentially appropriate geologic environments in the UAE.

  4. Addressing issues raised by stakeholders in the development of a deep geological repository in the Czech Republic

    International Nuclear Information System (INIS)

    Sumberova, Vera

    2004-01-01

    The mission of the Radioactive Waste Repository Authority (RAWRA) is to ensure the safe disposal of all existing and future radioactive waste. In order to fulfil this task RAWRA, in addition to the operation of radioactive waste repositories in the Czech Republic, coordinates all those activities relating to the construction of a deep geological repository. This long-term goal implies first creating and then building upon the public's confidence in the decision making process and the project as a whole as well as in RAWRA as a competent and efficient implementer since clearly public acceptance is an essential condition for a successful final outcome. Since its establishment in 1997 RAWRA has been looking for ways in which to inform the public about its activities and how to involve the various stakeholders in the development process. The communication tools employed to achieve this goal have, to date, depended on the specific stage of the process but RAWRA has aimed at a continuous improvement in its activities; consequently a large number of changes have been made to RAWRA's policy and approach in recent years. This paper, which aims to describe RAWRA's dialogue with stakeholders (mainly local communities), provides examples of the way in which issues raised by stakeholders concerning a repository are reflected in RAWRA's approach. (author)

  5. How to Shape a Successful Repository Program: Staged Development of Geologic Repositories for High-Level Waste

    International Nuclear Information System (INIS)

    Isaacs, T.

    2004-01-01

    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

  6. How to Shape a Successful Repository Program: Staged Development of Geologic Repositories for High-Level Waste

    Energy Technology Data Exchange (ETDEWEB)

    Isaacs, T.

    2004-10-03

    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.

  7. 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

  8. 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)

  9. Economics of mined geologic repositories

    International Nuclear Information System (INIS)

    Hofmann, P.L.; Dippold, D.G.

    1983-01-01

    During 1982, Congress considered legislation to provide for the development of repositories for the disposal of high-level radioactive waste and spent nuclear fuel. The result of this legislative effort was the Nuclear Waste Policy Act of 1982 (NWPA), PL 97-425, signed into law January 7, 1983. An important part of the NWPA was the establishment of special funds in the US Treasury for Waste Disposal and Interim Storage to be financed by user fees to pay for all costs of the program. An initial fee of 1.0 mill per kilowatt-hour was specified. The Secretary was asked to annually review the amount of the fees established... to evaluate whether collection of the fee will provide sufficient revenues to offset the costs... In the event of a prospective fee cost mismatch, the Secretary was asked to propose an adjustment to the fee to insure full cost recovery. A series of studies were sponsored by DOE in 1982 to estimate program costs, to calculate the necessary fees to assure cost recovery, and to address uncertainties that could affect future program costs and consequent fee schedules. A brief summary of the 1982 cost estimates is presented. Sources of key cost uncertainties are discussed and the bases for the cost recovery fee calculations are summarized. 17 references, 2 figures, 3 tables

  10. Development of low alkaline cementitious grouting materials for a deep geological repository

    International Nuclear Information System (INIS)

    Suzuki, Kenichiro; Miura, Norihiko; Iriya, Keishiro; Kobayashi, Yasushi

    2012-01-01

    In order to reduce uncertainties of long-term safety assessment for a High Level radioactive Waste (HLW) repository system, low alkaline cementitious grouting materials have been studied. The pH of the leachate from the grouting material is targeted to be below 11.0, since the degradation of the bentonite buffer and host rock is limited. The current work focused on the effects of pozzolanic reactions to reduce pH and the development of low alkaline cementitious injection materials in which super-micro ordinary Portland cement (SOPC) was partially replaced by silica fume (SF), micro silica (MS) and fly ash (FA). As it is important to realize how the grouting material will respond to a high injection pressure into the fracture, and in order to understand the penetrability of different low alkaline cement mixes and to observe their flow behavior through the fracture, injection tests were conducted by using a simulated model fracture of 2 m diameter made from parallel plates of acrylic acid resin and stainless steel. Experimental results of the basic properties for selecting suitable materials and that of injecting into a simulated fracture to assess the grouting performance are described

  11. 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

  12. Safety analysis of the proposed Canadian geologic nuclear waste repository

    International Nuclear Information System (INIS)

    Prowse, D.R.

    1977-01-01

    The Canadian program for development and qualification of a geologic repository for emplacement of high-level and long-lived, alpha-emitting waste from irradiated nuclear fuel has been inititiated and is in its initial development stage. Fieldwork programs to locate candidate sites with suitable geological characteristics have begun. Laboratory studies and development of models for use in safety analysis of the emplaced nuclear waste have been initiated. The immediate objective is to complete a simplified safety analysis of a model geologic repository by mid-1978. This analysis will be progressively updated and will form part of an environmental Assessment Report of a Model Fuel Center which will be issued in mid-1979. The long-term objectives are to develop advanced safety assessment models of a geologic repository which will be available by 1980

  13. Complex geologic characterization of the repository environment

    Energy Technology Data Exchange (ETDEWEB)

    Harper, T R [British Petroleum Research Center, Sunberry, England; Szymanski, J S

    1982-01-01

    The present basis for characterizing geological environments is identified in this paper, and the additional requirements imposed by the need to isolate high-level waste safely are discussed. Solutions to these additional requirements are proposed. The time scale of concern and the apparent complexity of the required multidisciplinary approach are identified. It is proposed that an increased use of the geologic record, together with a recognition that all geologic processes operate within an interdependent system, be a key feature in geologic characterization of deep repositories.

  14. 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

  15. 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

  16. Geological study of radioactive waste repositories

    International Nuclear Information System (INIS)

    Oyama, Takahiro; Kitano, Koichi

    1987-01-01

    The investigation of the stability and the barrier efficiency of the deep underground radioactive waste repositories become a subject of great concern. The purpose of this paper is to gather informations on the geology, engineering geology and hydrogeology in deep galleries in Japan. Conclusion can be summarised as follows: (1) The geological structure of deep underground is complicated. (2) Stress in deep underground is greatly affected by crustal movement. (3) Rock-burst phenomena occur in the deep underground excavations. (4) In spite of deep underground, water occasionally gush out from the fractured zone of rock mass. These conclusion will be useful for feasibility study of underground waste disposal and repositories in Japan. (author)

  17. 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)

  18. 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)

  19. Development of Next-generation Technology for Integrated Site Characterization of Deep Geological Repositories

    International Nuclear Information System (INIS)

    Osawa, H.; Umeki, H.; Ota, K.; Hama, K.; Sawada, A.; Takeuchi, S.; Semba, T.; Takase, H.; McKinley, I.G.

    2009-01-01

    As site investigation proceeds and information obtained on geological environments increases, the characterization plan has to be iteratively reviewed and modified to reflect improved understanding. Such modification would also be needed when changes occur in technical or socio-political boundary conditions. JAEA teams involved in implementation of URL projects have used a geo-synthesis data flow diagram to integrate a huge amount of practical experience in order to carry out such management functions. However, much of this experience was gained in the past, when it was possible for staff to learn by taking leading roles in novel, complex and important projects and learn by successes - and mistakes - under boundary conditions that were much more casual than they are at present. It is necessary to transfer such tacit knowledge to implementing and regulatory organizations in a practical manner before it is lost with the retirement of senior staff. An option being examined involves application of advanced technology, termed the Information Synthesis and Interpretation System (ISIS), to capture experience using Knowledge Engineering methods. This is being tested for practical applicability in an exercise involving stepwise 'optimization' of a site characterization plan. (authors)

  20. Geologic repository work breakdown structure and dictionary---Development and evaluation phase (PE-02)

    International Nuclear Information System (INIS)

    1991-08-01

    Revision 2 of the OGR Work Breakdown Structure and Dictionary -- Development and Evaluation Phase (PE-02) supersedes Revision 1, August 1989, in its entirety. The revision is to delete the ''Exploratory Shaft Facility'' work scape and replace it with ''Exploratory Studies Facility'' work scape

  1. Development of the JNC geological disposal technical information integration system subjected for repository design and safety assessment

    International Nuclear Information System (INIS)

    Ishihara, Yoshinao; Ito, Takashi; Kobayashi, Shigeki; Neyama, Atsushi

    2004-02-01

    On this work, system manufacture about disposal technology and safety assessment field was performed towards construction of the JNC Geological Disposal Technical Information Integration System which systematized three fields of technical information acquired in investigation (site characteristic investigation) of geology environmental conditions, disposal technology (design of deep repository), and performance/safety assessment. The technical information database managed focusing on the technical information concerning individual research of an examination, analysis, etc. and the parameter set database managed focusing on the set up data set used in case of comprehensive evaluation are examined. In order to support and promote share and use of the technical information registered and managed by the database, utility functions, such as a technical information registration function, technical information search/browse function, analysis support function, and visualization function, are considered, and the system realized in these functions is built. The built system is installed in the server of JNC, and the functional check examination is carried out. (author)

  2. Performance Assessment Strategy Plan for the Geologic Repository Program

    International Nuclear Information System (INIS)

    1990-01-01

    Performance assessment is a major constituent of the program being conducted by the US Department of Energy (DOE) to develop a geologic repository. Performance assessment is the set of activities needed for quantitative evaluations to assess compliance with the performance requirements in the regulations for a geologic repository and to support the development of the repository. The strategy for these evaluations has been documented in the Performance Assessment Strategy Plan (DOE, 1989). The implementation of the performance assessment strategy is defined in this document. This paper discusses the scope and objectives of the implementation plan, the relationship of the plan to other program plans, summarizes the performance assessment areas and the integrated strategy of the performance assessment program. 1 fig., 3 tabs

  3. Modelling of processes occurring in deep geological repository - development of new modules in the GoldSim environment

    International Nuclear Information System (INIS)

    Vopalka, D.; Lukin, D.; Vokal, A.

    2006-01-01

    Three new modules modelling the processes that occur in a deep geological repository have been prepared in the GoldSim computer code environment (using its Transport Module). These modules help to understand the role of selected parameters in the near-field region of the final repository and to prepare an own complex model of the repository behaviour. The source term module includes radioactive decay and ingrowth in the canister, first order degradation of fuel matrix, solubility limitation of the concentration of the studied nuclides, and diffusive migration through the surrounding bentonite layer controlled by the output boundary condition formulated with respect to the rate of water flow in the rock. The corrosion module describes corrosion of canisters made of carbon steel and transport of corrosion products in the near-field region. This module computes balance equations between dissolving species and species transported by diffusion and/or advection from the surface of a solid material. The diffusion module that includes also non-linear form of the interaction isotherm can be used for an evaluation of small-scale diffusion experiments. (author)

  4. Modelling of processes occurring in deep geological repository - Development of new modules in the GoldSim environment

    Science.gov (United States)

    Vopálka, D.; Lukin, D.; Vokál, A.

    2006-01-01

    Three new modules modelling the processes that occur in a deep geological repository have been prepared in the GoldSim computer code environment (using its Transport Module). These modules help to understand the role of selected parameters in the near-field region of the final repository and to prepare an own complex model of the repository behaviour. The source term module includes radioactive decay and ingrowth in the canister, first order degradation of fuel matrix, solubility limitation of the concentration of the studied nuclides, and diffusive migration through the surrounding bentonite layer controlled by the output boundary condition formulated with respect to the rate of water flow in the rock. The corrosion module describes corrosion of canisters made of carbon steel and transport of corrosion products in the near-field region. This module computes balance equations between dissolving species and species transported by diffusion and/or advection from the surface of a solid material. The diffusion module that includes also non-linear form of the interaction isotherm can be used for an evaluation of small-scale diffusion experiments.

  5. 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

  6. 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)

  7. 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)

  8. Planning geological underground repositories - Communicating with society

    International Nuclear Information System (INIS)

    Schenkel, W.; Gallego Carrera, D.; Renn, O.; Dreyer, M.

    2009-06-01

    The project 'Planning geological underground repositories: Communicating with society', financed by the Swiss Federal Office for Energy, aimed at identifying basic principles for an appropriate information and communication strategy in the process of finding an underground site to store radioactive wastes. The topic concerns an issue increasingly discussed in modern societies: How to improve the dialogue between science, infrastructure operators, public authorities, groups in civil society and the population to answer complex problems? Against this background, in the project the following questions were taken into account: (i) How can the dialogue between science, politics, economy, and the (non-)organised public be arranged appropriately? Which principles are to be considered in organising this process? How can distrust within the population be reduced and confidence in authorities and scientific expertise be increased? (ii) How can society be integrated in the process of decision-making so that this process is perceived as comprehensible, acceptable and legitimate? To answer these questions, an analysis method based on scientific theory and methodology was developed, which compares national participation and communication processes in finding underground storage sites in selected countries. Case studies have been carried out in Germany, Sweden, Belgium, and Switzerland. By using specific criteria to evaluate communication processes, the strong points as well as the drawbacks of the country-specific concepts of information, communication and participation have been analysed in a comparing dimension. By taking into account the outcomes, prototypical scenarios have been deduced that can serve as a basis for compiling a reference catalogue of measures, which is meant to support the Swiss communication strategy in the finding of an appropriate site for a nuclear waste repository. Following conclusions can be drawn from the international comparison: (i) Open and

  9. 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

  10. Relationship of engineering geology to conceptual repository design in the Gibson Dome area, Utah

    International Nuclear Information System (INIS)

    Helgerson, R.; Henderson, N.

    1984-01-01

    The Paradox Basin in Southeastern Utah is being investigated as a potential site for development of a high-level nuclear waste repository. Geologic considerations are key areas of concern and influence repository design from a number of aspects: depth to the host rock, thickness of the host rock, and hydrologic conditions surrounding the proposed repository are of primary concern. Surface and subsurface investigations have provided data on these key geologic factors for input to the repository design. A repository design concept, based on the surface and subsurface geologic investigations conducted at Gibson Dome, was synthesized to provide needed information on technical feasibility and cost for repository siting decision purposes. Significant features of the surface and subsurface repository facilities are presented. 5 references, 4 figures

  11. Safety assessment of geologic repositories for nuclear waste

    International Nuclear Information System (INIS)

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

    1977-01-01

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

  12. Nurture of human resources for geological repository program

    International Nuclear Information System (INIS)

    Fujiwara, A.

    2004-01-01

    The Japanese geological repository program entered the implementing stage in 2002. At the implementing stage of the program, different sectors need various human resources to conduct their functions. This paper discusses a suitable framework of nurture of the human resources to progress the geological repository program. The discussion is based on considering of specific characters involved in the program and of the multidisciplinary knowledge related to geological disposal. Considering the specific characters of the project, two types of the human resources need to be nurtured. First type is the core persons with the highest knowledge on geological disposal. They are expected to communicate with the various stakeholders and pass down the whole knowledge of the project to the next generation. Another is to conduct the project as the managers, the engineers and the workers. The former human resources can be developed through the broad practice and experience in each sector. The latter human resources can be effectively developed by training of the fundamental knowledge on geological disposal at training centers as well as by conventional on-the-job training. The sectors involved in the program need to take their own roles in the nurture of these human resources. (author)

  13. 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)

  14. 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

  15. 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

  16. Geological disposal system development

    International Nuclear Information System (INIS)

    Kang, Chul Hyung; Kuh, J. E.; Kim, S. K. and others

    2000-04-01

    Spent fuel inventories to be disposed of finally and design base spent fuel were determined. Technical and safety criteria for a geological repository system in Korea were established. Based on the properties of spent PWR and CANDU fuels, seven repository alternatives were developed and the most promising repository option was selected by the pair-wise comparison method from the technology point of view. With this option preliminary conceptual design studies were carried out. Several module, e.g., gap module, congruent release module were developed for the overall assessment code MASCOT-K. The prominent overseas databases such as OECD/NEA FEP list were are fully reviewed and then screened to identify the feasible ones to reflect the Korean geo-hydrological conditions. In addition to this the well known scenario development methods such as PID, RES were reviewed. To confirm the radiological safety of the proposed KAERI repository concept the preliminary PA was pursued. Thermo-hydro-mechanical analysis for the near field of repository were performed to verify thermal and mechanical stability for KAERI repository system. The requirements of buffer material were analyzed, and based on the results, the quantitative functional criteria for buffer material were established. The hydraulic and swelling property, mechanical properties, and thermal conductivity, the organic carbon content, and the evolution of pore water chemistry were investigated. Based on the results, the candidate buffer material was selected

  17. Geological disposal system development

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Chul Hyung; Kuh, J. E.; Kim, S. K. and others

    2000-04-01

    Spent fuel inventories to be disposed of finally and design base spent fuel were determined. Technical and safety criteria for a geological repository system in Korea were established. Based on the properties of spent PWR and CANDU fuels, seven repository alternatives were developed and the most promising repository option was selected by the pair-wise comparison method from the technology point of view. With this option preliminary conceptual design studies were carried out. Several module, e.g., gap module, congruent release module were developed for the overall assessment code MASCOT-K. The prominent overseas databases such as OECD/NEA FEP list were are fully reviewed and then screened to identify the feasible ones to reflect the Korean geo-hydrological conditions. In addition to this the well known scenario development methods such as PID, RES were reviewed. To confirm the radiological safety of the proposed KAERI repository concept the preliminary PA was pursued. Thermo-hydro-mechanical analysis for the near field of repository were performed to verify thermal and mechanical stability for KAERI repository system. The requirements of buffer material were analyzed, and based on the results, the quantitative functional criteria for buffer material were established. The hydraulic and swelling property, mechanical properties, and thermal conductivity, the organic carbon content, and the evolution of pore water chemistry were investigated. Based on the results, the candidate buffer material was selected.

  18. Development of the methodology on priority of element-specific biosphere parameters for geological disposal applicable to any proposed repository site

    International Nuclear Information System (INIS)

    Kato, Tomoko; Ohi, Takao; Suzuki, Yuji

    2009-01-01

    It is difficult to acquire all of biosphere parameters for geological disposal at the repository site because several hundreds of the parameters have to be dealt with in one calculation case of the biosphere assessment. Before site-specific activities, it is important to develop the data acquisition methodology of biosphere parameters applicable to any proposed repository site. The methodology for identification of the priority of the parameters was developed for the effective data acquisition of biosphere parameters at the site. First of all, flow diagram was constructed to evaluate the availability of the existing generic biosphere dataset. It was found to be effective for the data acquisition at the site to focus on the element-specific parameters with the existing dataset. Secondly, the priority of the data acquisition was identified for element-specific parameters at the site, with considering the variation of dose rate by combining the significant element-specific parameters. The availability of the existing generic biosphere dataset and the priority on data acquisition were identified for the element-specific parameters of key radionuclides in the safety assessment of geological disposal that should be acquired at the site. This priority list would be useful for effective data acquisition at the site. (author)

  19. NAGRA - Sites for geological repositories - Geological surveys for stage 3

    International Nuclear Information System (INIS)

    2014-01-01

    This brochure published by the Swiss National Cooperative for the Disposal of Radioactive Waste (NAGRA) examines the aims involved in the selection of sites for deep geological repositories for nuclear wastes in Switzerland. Various methods involved in their implementation are described. These include 3D-seismology, deep probe drillings, shallow drillings as well as field studies, gravimetric measurements and the study of the electrical properties of the ground and rock involved. These factors are discussed in detail. Maps are presented of the locations that are to be surveyed and details of the selected perimeters are shown. Also, the layout of a sample drilling site is presented. A timescale for the various surveys and work to be done is presented

  20. Methodology for the development of scenarios for the evaluation of the behaviour of a deep geological repository for high-level radioactive waste in a granite formation

    International Nuclear Information System (INIS)

    Cortes Martin, A.; Alonso, J.; Gonzalez, E.

    1996-01-01

    In time, deep geological repositories for radioactive waste undergo significant environmental changes caused either by natural processes or by human actions. In view of a long-term safety analysis, it is fundamental to identify all the possible evolutions of the system. This process is denominated scenario development. This paper deals with the methodology used to generate scenarios within the framework of the AGP (Deep Geological Repository) project for assessing behaviour in granite medium. It begins with a brief description of the methodology used to identify the relevant factors for the safety analysis on the system. It then presents the details of the actual scenario-generating methodology which consists of dividing the entire system into barrier states or subsystems a graphic procedure by means of which the factors are represented in relation to their predictable impact or extent of their effect on the subsystems. This methodology is a good tool for displaying and grouping the most significant scenarios for the subsequent analysis of consequences. (Author)

  1. Impacts of new developments in partitioning and transmutation on the disposal of high-level nuclear waste in a mined geologic repository

    International Nuclear Information System (INIS)

    Ramspott, L.D.; Jor-Shan Choi; Halsey, W.; Pasternak, A.; Cotton, T.; Burns, J.; McCabe, A.; Colglazier, W.; Lee, W.W.L.

    1992-03-01

    During the 1970s, the United States and other countries thoroughly evaluated the options for the safe and final disposal of high-level radioactive wastes (HLW). The worldwide scientific community concluded that deep geologic disposal was clearly the most technically feasible alternative. They also ranked the partitioning and transmutation (P-T) of radionuclides among the least favored options. A 1982 report by the International Atomic Energy Agency summarized the key reasons for that ranking: ''Since the long-term hazards are already low, there is little incentive to reduce them further by P-T. Indeed the incremental costs of introducing P-T appear to be unduly high in relation to the prospective benefits.'' Recently, the delays encountered by the US geologic disposal program for HLW, along with advanced in the development of P-T concepts, have led some to propose P-T as a means of reducing the long-term risks from the radioactive wastes that require disposal and thus making it easier to site, license, and build a geologic repository. This study examines and evaluates the effects that introducing P-T would have on the US geologic disposal program

  2. 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)

  3. Safeguards policy and strategies: An IAEA perspective for spent fuel in geological repositories

    International Nuclear Information System (INIS)

    Fattah, A.

    2002-01-01

    Safeguards for nuclear materials in geologic repositories have to be continued even after the repository has been backfilled and sealed. The nuclear materials disposed in a geologic repository may pose a higher and long-term proliferation risk because the inventory is many times the 'significant quantity' needed safeguards. The safeguards measures must be flexible enough to respond to the changing development of technology and changing need for current as well as future generations. Change in social, economic, environmental and other scenarios might demand recovery of nuclear and other materials from the repository sometime in the future. (author)

  4. 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)

  5. Operational safety of geological disposal: IRSN project 'EXREV' for developing a safety assessment strategy for the operation and reversibility of a geological repository

    International Nuclear Information System (INIS)

    Tichauer, M.; Pellegrini, D.; Serres, C.; Besnus, F.

    2014-01-01

    A high-level waste geological disposal facility is envisioned by the legislator in the French Planning Act no. 2006-739 of 28 June 2006. This act sets major milestones for the operator (Andra) in 2013 (public debate), 2015 (licensing) and 2025 (operation). In the framework of the regulatory review process, IRSN's mission is to conduct an assessment of the safety case provided by Andra at every stage of the process for the French regulator, namely the Nuclear Safety Authority (ASN). In 2005, IRSN gathered more than twenty years of research and expertise in order to provide a comprehensive appraisal of the 'Dossier 2005' prepared by Andra, related to the feasibility of a geological disposal in the Callovo-Oxfordian clay formation. At this time, the description of the operational phase was only at a preliminary stage, but this step paved the way for developing an assessment strategy of the operational phase. In this perspective, IRSN set up the EXREV project in 2008 in order to build up a doctrine and to identify key safety issues to be dealt with. (authors)

  6. Safety assessment methodology for waste repositories in deep geological formations

    International Nuclear Information System (INIS)

    Chapuis, A.M.; Lewi, J.; Pradel, J.; Queniart, D.; Raimbault, P.; Assouline, M.

    1986-06-01

    The long term safety of a nuclear waste repository relies on the evaluation of the doses which could be transferred to man in the future. This implies a detailed knowledge of the medium where the waste will be confined, the identification of the basic phenomena which govern the migration of the radionuclides and the investigation of all possible scenarios that may affect the integrity of the barriers between the waste and the biosphere. Inside the Institute of protection and nuclear safety of the French Atomic Energy Commission (CEA/IPSN), the Department of the Safety Analysis (DAS) is currently developing a methodology for assessing the safety of future geological waste repositories, and is in charge of the modelling development, while the Department of Technical Protection (DPT) is in charge of the geological experimental studies. Both aspects of this program are presented. The methodology for risk assessment stresses the needs for coordination between data acquisition and model development which should result in the obtention of an efficient tool for safety evaluation. Progress needs to be made in source and geosphere modelling. Much more sophisticated models could be used than the ones which is described; however sensitivity analysis will determine the level of sophistication which is necessary to implement. Participation to international validation programs are also very important for gaining confidence in the approaches which have been chosen

  7. The influence of geological loading on the structural integrity of an underground nuclear waste repository

    International Nuclear Information System (INIS)

    Jakeman, N.

    1985-08-01

    Stresses are developed in underground nuclear waste repositories as a result of applied loads from geological movements caused by the encroachment of ice sheets or seismic activity for example. These stresses may induce fracturing of the waste matrix, repository vault and nearfield host geology. This fracturing will enhance the advective flow and allow more-rapid transfer of radionuclides from their encapsulation through the repository barriers and nearfield host rock. Geological loads may be applied either gradually as in crustal folding or encroachment of ice sheets, or rapidly as in the case of seismic movements. The analysis outlined in this report is conducted with a view to including the effects of geological loading in a probabilistic repository site assessment computer code such as SYVAC. (author)

  8. 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)

  9. 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

  10. Kincardine deep geologic repository proposal and the public

    International Nuclear Information System (INIS)

    Squire, T.

    2005-01-01

    'Full text:' In 2002, the Municipality of Kincardine and OPG signed a Memorandum of Understanding (MOU) regarding the long-term management of low and intermediate level radioactive wastes. The purpose of the MOU was for OPG, in consultation with Kincardine, to develop a plan for the long-term management of low and intermediate level waste at OPG's Western Waste Management Facility (WWMF) located on the Bruce site. An independent assessment, which included geotechnical feasibility and safety analyses, a community attitude survey and interviews with local residents, businesses and tourists, and economic modeling to determine the potential benefits and impacts, was completed in February 2004. Ultimately, Kincardine Council endorsed a resolution (Kincardine Council no. 2004-232) to: 'endorse the opinion of the Nuclear Waste Steering Committee and select the 'Deep Rock Vault' option as the preferred course of study in regards to the management of low and intermediate level radioactive waste'. The surrounding municipalities of Saugeen Shores, Brockton, Arran-Elderslie, and Huron-Kinloss expressed their support for the Deep Geologic Repository proposal. This presentation discusses the history, major steps and public processes surrounding the Kincardine Deep Geologic Repository proposal. (author)

  11. 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

  12. Monitoring of geological repositories for high level radioactive waste

    International Nuclear Information System (INIS)

    2001-04-01

    Geological repositories for disposal of high level radioactive waste are designed to provide isolation of the waste from human environment for many thousands of years. This report discusses the possible purposes for monitoring geological repositories at the different stages of a repository programme, the use that may be made of the information obtained and the techniques that might be applied. This report focuses on the different objectives that monitoring might have at various stages of a programme, from the initiation of work on a candidate site, to the period after repository closure. Each objective may require somewhat different types of information, or may use the same information in different ways. Having evaluated monitoring requirements, the report concludes with a brief evaluation of available monitoring techniques

  13. Analysis of the geological stability of a hypothetical radioactive waste repository in a bedded salt formation

    International Nuclear Information System (INIS)

    Tierney, M.S.; Lusso, F.; Shaw, H.R.

    1978-01-01

    This document reports on the development of mathematical models used in preliminary studies of the long-term safety of radioactive wastes deeply buried in bedded salt formations. Two analytical approaches to estimating the geological stability of a waste repository in bedded salt are described: (a) use of probabilistic models to estimate the a priori likelihoods of release of radionuclides from the repository through certain idealized natural and anthropogenic causes, and (b) a numerical simulation of certain feedback effects of emplacement of waste materials upon ground-water access to the repository's host rocks. These models are applied to an idealized waste repository for the sake of illustration

  14. Deep geological repository: Starting communication at potentially suitable sites

    International Nuclear Information System (INIS)

    Sumberova, Vera

    2001-01-01

    The siting of a deep geological repository in the Czech Republic is and will be a complicated process, since it is the first siting process of a nuclear facility designed from the start to be located at non-nuclear sites and to be organised under democratic conditions. This presentation describes the concept of radioactive waste and spent nuclear management in the Czech Republic, Communication activities of Radioactive Waste Repository Authority (RAWRA) with local representatives and lessons learned

  15. Scientific basis for a safety case of deep geological repositories

    Energy Technology Data Exchange (ETDEWEB)

    Noseck, Ulrich; Becker, Dirk-Alexander; Brasser, Thomas [and others

    2012-11-15

    Within this project strategies and methods to build a safety case for deep geological repositories are further developed. This includes also the scientific fundamentals as a basis of the safety case. In the international framework the methodology of the Safety Case is frequently applied and continuously improved. According to definitions from IAEA and NEA the Safety Case is a compilation of arguments and facts, which describe, quantify and support the safety and the degree of confidence in the safety of the geological repository. The safety of the geological repository should be demonstrated by the safety case. The safety case is the basis for essential decisions during a repository programme. It comprises the results of safety assessments in combination with additional information like multiple lines of evidence and a discussion of robustness and quality of the repository, its design and the quality of all safety assessments including the basic assumptions. A crucial element of the Safety Case is the long-term safety analysis, i.e. the systematic analysis of the hazards connected with the facility and the capability of site and repository design to ensure the required safety functions and to fulfill the technical claims. Long-term safety analysis requires a powerful and qualified programme package, which contains appropriate hardware and software as well as well trained and experienced modellers performing the model calculations. The calculation tools used within safety cases need to be checked and verified and continuously adapted to the state-of-the-art science and technology. Especially it needs to be applicable to a real repository system. For the assessment of safety a deep process understanding is necessary. The R and D work performed within this project will contribute to the improvement of process and system understanding as well as to the further development of methods and strategies applied in the safety case. Emphasis was put on the following aspects

  16. Scientific basis for a safety case of deep geological repositories

    International Nuclear Information System (INIS)

    Noseck, Ulrich; Becker, Dirk-Alexander; Brasser, Thomas

    2012-11-01

    Within this project strategies and methods to build a safety case for deep geological repositories are further developed. This includes also the scientific fundamentals as a basis of the safety case. In the international framework the methodology of the Safety Case is frequently applied and continuously improved. According to definitions from IAEA and NEA the Safety Case is a compilation of arguments and facts, which describe, quantify and support the safety and the degree of confidence in the safety of the geological repository. The safety of the geological repository should be demonstrated by the safety case. The safety case is the basis for essential decisions during a repository programme. It comprises the results of safety assessments in combination with additional information like multiple lines of evidence and a discussion of robustness and quality of the repository, its design and the quality of all safety assessments including the basic assumptions. A crucial element of the Safety Case is the long-term safety analysis, i.e. the systematic analysis of the hazards connected with the facility and the capability of site and repository design to ensure the required safety functions and to fulfill the technical claims. Long-term safety analysis requires a powerful and qualified programme package, which contains appropriate hardware and software as well as well trained and experienced modellers performing the model calculations. The calculation tools used within safety cases need to be checked and verified and continuously adapted to the state-of-the-art science and technology. Especially it needs to be applicable to a real repository system. For the assessment of safety a deep process understanding is necessary. The R and D work performed within this project will contribute to the improvement of process and system understanding as well as to the further development of methods and strategies applied in the safety case. Emphasis was put on the following aspects

  17. Communication on the Safety Case for a Deep Geological Repository

    International Nuclear Information System (INIS)

    Bailey, Lucy; Bernier, Frederik; Bollingerfehr, Wilhelm; Cunado, Miguel; Ilett, Doug; Kwong, Gloria; ); Noseck, Ulrich; Roehlig, Klaus; Van Luik, Abe; Weber, Jan; Weetjens, Eef

    2017-01-01

    Communication has a specific role to play in the development of deep geological repositories. Building trust with the stakeholders involved in this process, particularly within the local community, is key for effective communication between the authorities and the public. There are also clear benefits to having technical experts hone their communication skills and having communication experts integrated into the development process. This report has compiled lessons from both failures and successes in communicating technical information to non-technical audiences. It addresses two key questions in particular: what is the experience base concerning the effectiveness or non-effectiveness of different tools for communicating safety case results to a non-technical audience and how can communication based on this experience be improved and included into a safety case development effort from the beginning? (authors)

  18. Development of Earthquake Ground Motion Input for Preclosure Seismic Design and Postclosure Performance Assessment of a Geologic Repository at Yucca Mountain, NV

    International Nuclear Information System (INIS)

    I. Wong

    2004-01-01

    This report describes a site-response model and its implementation for developing earthquake ground motion input for preclosure seismic design and postclosure assessment of the proposed geologic repository at Yucca Mountain, Nevada. The model implements a random-vibration theory (RVT), one-dimensional (1D) equivalent-linear approach to calculate site response effects on ground motions. The model provides results in terms of spectral acceleration including peak ground acceleration, peak ground velocity, and dynamically-induced strains as a function of depth. In addition to documenting and validating this model for use in the Yucca Mountain Project, this report also describes the development of model inputs, implementation of the model, its results, and the development of earthquake time history inputs based on the model results. The purpose of the site-response ground motion model is to incorporate the effects on earthquake ground motions of (1) the approximately 300 m of rock above the emplacement levels beneath Yucca Mountain and (2) soil and rock beneath the site of the Surface Facilities Area. A previously performed probabilistic seismic hazard analysis (PSHA) (CRWMS M and O 1998a [DIRS 103731]) estimated ground motions at a reference rock outcrop for the Yucca Mountain site (Point A), but those results do not include these site response effects. Thus, the additional step of applying the site-response ground motion model is required to develop ground motion inputs that are used for preclosure and postclosure purposes

  19. Development of Earthquake Ground Motion Input for Preclosure Seismic Design and Postclosure Performance Assessment of a Geologic Repository at Yucca Mountain, NV

    Energy Technology Data Exchange (ETDEWEB)

    I. Wong

    2004-11-05

    This report describes a site-response model and its implementation for developing earthquake ground motion input for preclosure seismic design and postclosure assessment of the proposed geologic repository at Yucca Mountain, Nevada. The model implements a random-vibration theory (RVT), one-dimensional (1D) equivalent-linear approach to calculate site response effects on ground motions. The model provides results in terms of spectral acceleration including peak ground acceleration, peak ground velocity, and dynamically-induced strains as a function of depth. In addition to documenting and validating this model for use in the Yucca Mountain Project, this report also describes the development of model inputs, implementation of the model, its results, and the development of earthquake time history inputs based on the model results. The purpose of the site-response ground motion model is to incorporate the effects on earthquake ground motions of (1) the approximately 300 m of rock above the emplacement levels beneath Yucca Mountain and (2) soil and rock beneath the site of the Surface Facilities Area. A previously performed probabilistic seismic hazard analysis (PSHA) (CRWMS M&O 1998a [DIRS 103731]) estimated ground motions at a reference rock outcrop for the Yucca Mountain site (Point A), but those results do not include these site response effects. Thus, the additional step of applying the site-response ground motion model is required to develop ground motion inputs that are used for preclosure and postclosure purposes.

  20. Regional and site geological frameworks : proposed Deep Geologic Repository, Bruce County, Ontario

    Energy Technology Data Exchange (ETDEWEB)

    Raven, K.; Sterling, S.; Gaines, S.; Wigston, A. [Intera Engineering Ltd., Ottawa, ON (Canada); Frizzell, R. [Nuclear Waste Management Organization, Toronto, ON (Canada)

    2009-07-01

    The Nuclear Waste Management Organization is conducting geoscientific studies on behalf of Ontario Power Generation into the proposed development of a Deep Geologic Repository (DGR) for low and intermediate level radioactive waste (L and ILW) at the Bruce site, near Tiverton, Ontario. This paper presented a regional geological framework for the site that was based on a review of regional drilling; structural geology; paleozoic stratigraphy and sedimentology; a 3D geological framework model; a DGR geological site characterization model; bedrock stratigraphy and marker beds; natural fracture frequency data; and formation predictability. The studies have shown that the depth, thickness, orientation and rock quality of the 34 rock formations, members or units that comprise the 840 m thick Paleozoic bedrock sequence at the Bruce site are very uniform and predictable over distances of several kilometres. The proposed DGR will be constructed as an engineered facility comprising a series of underground emplacement rooms at a depth of 680 metres below ground within argillaceous limestones. The geoscientific studies are meant to provide a basis for the development of descriptive geological, hydrogeological and geomechanical models of the DGR site that will facilitate environmental and safety assessments. 11 refs., 3 tabs., 9 figs.

  1. Environmental impact assessments and geological repositories for radioactive waste

    International Nuclear Information System (INIS)

    O'Sullivan, P.; McKirdy, B.; Askarieh, M.; Bond, A.; Russell, S.

    1999-01-01

    Since 1985 it has been obligatory that facilities in the European Union designed for the permanent storage or disposal of radioactive waste be assessed to determine their effects on the environment. This assessment must be undertaken in advance of any decision by national authorities to give consent for development work to proceed. Member States are given wide discretion on how the above requirements are implemented in practice, e.g. the relevant European Council Directives call for the results of the environmental assessment to be made available to the public before development consent is granted but the detailed arrangements for dissemination of such information and procedures for public consultation are determined by individual Member States. Although the Directives require an assessment of the direct and indirect effects of a project on human beings and on various elements of the natural environment, they are non-specific as to what particular impacts should be addressed, particularly as regards the effects of a project on human beings. Therefore, for example, each Member State may decide whether or not social, health and economic impacts should be included in the assessment. This paper discusses the above issues. It proposes a model approach to environmental impact assessment in the context of geological repositories, including the role of the assessment on the overall decision processes for repository development, the scope and content of the assessment report, and approaches to public involvement

  2. Siting regions for deep geological repositories. Why just here?

    International Nuclear Information System (INIS)

    Rieser, A.

    2009-09-01

    This report helps to the popularization of the Nagra works accomplished for the management and disposal of the radioactive wastes in Switzerland. The programme for management and disposal of the radioactive wastes are extensively determined by regulations. Protection of mankind and environment is the primary objective. The basic storage process is considered as having been solved. The question addressed in the report is where the facility has to be built; the site selection procedure includes five steps: 1) according to their type the wastes have to be allocated to two different repositories: for low- and intermediate-level wastes (L/ILW), and for high-level and alpha-toxic wastes (HLW); 2) the safety concept for both repositories and the requirements on the geology have to be determined; 3) large suitable geological-tectonic zones must be found where repositories could be built; 4) in these geological zones a suitable host rock has to be identified; 5) the most important spatial geological conditions of the host rock (minimum depth with respect to surface erosion, maximum depth in terms of engineering requirements, lateral extent) have to be identified. Based on these criteria, three suitable siting regions for a HLW repository were found in the North of Switzerland. The preferred host rock is Opalinus clay because of its very low permeability; it is therefore an excellent barrier against nuclide transport. In the three proposed siting regions, Opalinus clay is present in sufficient volumes at a suitable depth. For a L/ILW repository six different possible siting regions were identified, five in Northern Switzerland and one in Central Switzerland. In the three siting regions found for a possible HLW repository, it would also be possible to built a combined repository for both HLW and L/ILW wastes

  3. Optimization method for dimensioning a geological HLW waste repository

    International Nuclear Information System (INIS)

    Ouvrier, N.; Chaudon, L.; Malherbe, L.

    1990-01-01

    This method was developed by the CEA to optimize the dimensions of a geological repository by taking account of technical and economic parameters. It involves optimizing radioactive waste storage conditions on the basis of economic criteria with allowance for specified thermal constraints. The results are intended to identify trends and guide the choice from among available options: simple and highly flexible models were therefore used in this study, and only nearfield thermal constraints were taken into consideration. Because of the present uncertainty on the physicochemical properties of the repository environment and on the unit cost figures, this study focused on developing a suitable method rather than on obtaining definitive results. The optimum values found for the two media investigated (granite and salt) show that it is advisable to minimize the interim storage time, implying the containers must be separated by buffer material, whereas vertical spacing may not be required after a 30-year interim storage period. Moreover, the boreholes should be as deep as possible, on a close pitch in widely spaced handling drifts. These results depend to a considerable extent on the assumption of high interim storage costs

  4. Environmental impact assessments and geological repositories: A model process

    International Nuclear Information System (INIS)

    Webster, S.

    2000-01-01

    In a recent study carried out for the European Commission, the scope and application of environmental impact assessment (EIA) legislation and current EIA practice in European Union Member States and applicant countries of Central and Eastern Europe was investigated, specifically in relation to the geological disposal of radioactive waste. This paper reports the study's investigations into a model approach to EIA in the context of geological repositories, including the role of the assessment in the overall decision processes and public involvement. (author)

  5. Current status of the Japanese geological repository programme

    International Nuclear Information System (INIS)

    Kitayama, Kazumi

    2007-01-01

    The programme for disposal of radioactive waste in Japan is now moving ahead on a number of fronts. On the regulatory side, responsibility for TRU waste disposal has been assigned to NUMO and guidelines for the safety goals for disposal of LLW have been published. NUMO, as the implementer for the deep geological disposal programme, has been developing the special tools for project management that are needed as a result of the decision to adopt a volunteering approach to siting. NUMO is also building up the technical infrastructure for flexible tailoring of site characterisation, repository design and the associated safety assessment to the conditions found in any volunteer site. This work requires openness and transparency in decision-making but, as several sites may need to be investigated in parallel, particular emphasis is placed on operational practicality. (author)

  6. 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

  7. Establishment of advanced integration technology for site characterization of deep geological repository. Development of information synthesis and interpretation system. Annual report 2007

    International Nuclear Information System (INIS)

    Osawa, Hideaki; Umeki, Hiroyuki; Ota, Kunio; Maekawa, Keisuke; Kunimaru, Takanori; Niizato, Tadafumi; Asamori, Koichi; Yamanaka, Yoshiaki; Shigehiro, Michiko; Abe, Hironobu; Hama, Katsuhiro; Takeuchi, Shinji; Amano, Kenji; Saegusa, Hiromitsu; Matsukawa, Toshiyuki; Miyamoto, Tetsuo; Toyoda, Gakuji; Sawada, Atsushi; Shimada, Akiomi

    2008-11-01

    This project is planned as a five-year program aiming to develop an advanced integration technology for characterization of a site for radioactive waste geological disposal. It is carried out by the Geological Isolation Research and Development Directorate of Japan Atomic Energy Agency with the fund of Agency for Natural Resources and Energy of the Ministry of Economy, Trade and Industry. This report summarizes the outcome of the first year (FY 2007) activities of the project. The site characterization is a dynamic and complex process and needs close linkage with repository design and performance assessment (PA). A geosynthesis methodology has been developed for integrating site characterization information into design and PA, and applied for e.g. on-going JAEA's studies at two generic URLs at Mizunami and Horonobe. This methodology explicitly presents an information flow (often referred to as geosynthesis data flow diagram or data flow diagram, in short) from measurements by site investigation to generating data sets for design and PA. It is a useful tool for guiding the site characterization in a transparent and traceable manner. As site investigation proceeds and information being obtained on geological environments of the site increases, the site characterization plan is iteratively reviewed and modified reflecting the updated information. Such modification would also be needed when changes would occur on socio-political boundary conditions. In fact, the data flow diagrams for two generic URL projects have been revised several times so far due to the increase in the amount of information on geological environments and changes of societal conditions. An advanced technology aimed at in this project is therefore focused on developing flexible approach and tools, which is named as Information Synthesis and Interpretation System (ISIS), to support the stepwise 'optimization' of the site characterization plan. In FY 2007, a basic concept for ISIS has been developed

  8. 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

  9. IAEA perspectives on geological repositories. Address at the international conference on geological repositories, Denver, 1 November 1999

    International Nuclear Information System (INIS)

    ElBaradei, M.

    1999-01-01

    In his address at the International Conference on Geological Repositories (Denver, 1 November 1999), the Director General of the IAEA gave a general presentation of the problem of disposal of high-level radioactive waste, and described the current situation in the countries using nuclear energy including present and future Agency's activities

  10. Aspects of the studies for construction of a deep geological repository in Republic of Bulgaria. Concept for development of a specialized database for the purposes of siting and design of a deep geological repository in Republic of Bulgaria

    International Nuclear Information System (INIS)

    Tomov, E.; Yordanova, V.

    2009-01-01

    The strategy for the management of spent nuclear fuel and radioactive waste there are considered three options for spent fuel management : Transportation of the all spent fuel for storage and reprocessing; Removal of a part of the spent fuel for storage and reprocessing and store the rest in the repository for long-term dry storage for at least 50 years, i e postponement of the decision making; Transportation of the spent fuel to Russia for storage and processing, return of the high-level activity waste from processing for storage and disposal in Bulgaria, further storage of the spent fuel at NPP Kozloduy

  11. 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

  12. Effects of heat from high-level waste on performance of deep geological repository components

    International Nuclear Information System (INIS)

    1984-11-01

    This report discusses the effects of heat on the deep geological repository systems and its different components. The report is focussed specifically on effects due to thermal energy release solely from high-level waste or spent fuel. It reviews the experimental data and theoretical models of the effects of heat both on the behaviour of engineered and natural barriers. A summary of the current status of research and repository development including underground test facilities is presented

  13. Diversion path analysis for the Swedish geological repository

    International Nuclear Information System (INIS)

    Fritzell, Anni; Meer, Klaas Van Der

    2008-02-01

    The Swedish strategy to handle the spent fuel from the nuclear power plants is direct disposal in a geological repository. The safeguards regime covering all nuclear material in the state will be expanded to cover the new repository, which will require a novel safeguards approach due mainly to the inaccessibility of the fuel after disposal. The safeguards approach must be able to provide a high level of assurance that the fuel in the repository not diverted, but must also be resource efficient. An attractive approach with regards to use of resources is to monitor only the access points to the repository, i.e. the openings. The implementation of such an approach can only be allowed if it is shown to be sufficiently secure. With the purpose of determining the applicability of this 'black box' approach, a diversion path analysis for the Swedish geological repository has been carried out. The result from the analysis shows that all credible diversion paths could be covered by the black-box safeguards approach provided that the identified boundary conditions can be met

  14. Diversion path analysis for the Swedish geological repository

    Energy Technology Data Exchange (ETDEWEB)

    Fritzell, Anni (Dept. of Physics and Astronomy, Uppsala Univ., Uppsala (Sweden)); Meer, Klaas Van Der (Belgian Nuclear Research Center SCK.CEN (BG))

    2008-02-15

    The Swedish strategy to handle the spent fuel from the nuclear power plants is direct disposal in a geological repository. The safeguards regime covering all nuclear material in the state will be expanded to cover the new repository, which will require a novel safeguards approach due mainly to the inaccessibility of the fuel after disposal. The safeguards approach must be able to provide a high level of assurance that the fuel in the repository not diverted, but must also be resource efficient. An attractive approach with regards to use of resources is to monitor only the access points to the repository, i.e. the openings. The implementation of such an approach can only be allowed if it is shown to be sufficiently secure. With the purpose of determining the applicability of this 'black box' approach, a diversion path analysis for the Swedish geological repository has been carried out. The result from the analysis shows that all credible diversion paths could be covered by the black-box safeguards approach provided that the identified boundary conditions can be met

  15. 10 CFR 63.161 - Emergency plan for the geologic repository operations area through permanent closure.

    Science.gov (United States)

    2010-01-01

    ... Planning Criteria § 63.161 Emergency plan for the geologic repository operations area through permanent... 10 Energy 2 2010-01-01 2010-01-01 false Emergency plan for the geologic repository operations area... may occur at the geologic repository operations area, at any time before permanent closure and...

  16. The development of biosphere codes for use in assessment of the radiological impact of geological repositories for radioactive waste

    International Nuclear Information System (INIS)

    Coughtrey, P.J.; Kane, P.; Thorne, M.C.

    1982-12-01

    A statement of radiological protection criteria and measures of dose, forms the preface to a review of extant biosphere codes. Consideration is given to the implementation of the codes FOODII and NEPTUN for use with SYVAC. The selection of nuclides for consideration in SYVAC is discussed. Detailed specifications are provided for biosphere model developments desirable in the longer term. (author)

  17. Modelling of gas generation in deep geological repositories after closure

    International Nuclear Information System (INIS)

    Poller, A.; Mayer, G.; Darcis M; Smith, P.

    2016-12-01

    In deep geological repositories for radioactive waste, significant quantities of gases will be generated in the long term as a result of various processes, notably the anaerobic corrosion of metals and the degradation of organic materials. Therefore, the impact of gas production on post-closure safety of the repositories needs to be assessed as part of a safety case. The present report provides a comprehensive description of the quantitative modelling of gas generation and associated water consumption during the post-closure phase of deep geological repositories in Opalinus Clay based on current scientific knowledge and on current preliminary repository designs. This includes a presentation of the modelling basis, namely the conceptual and mathematical models, the input data used, the computer tools developed, the relevant uncertainties and principal programme / design options, as well as the derivation, analysis and discussion of specific assessment cases. The modelling is carried out separately for the two main sources of gas, which are the emplaced waste including the disposal containers; and the construction materials. The contribution of construction materials to gas generation rates in emplacement tunnels for spent fuel (SF) and vitrified high-level waste (HLW) is significant during several thousand years after closure. In the long term, however, the corrosion of the disposal canisters, which are in the reference case assumed to be fabricated of carbon steel, accounts for the vast majority of the total gas produced in these tunnels. The contribution of construction materials in emplacement caverns for long lived intermediate-level waste (ILW) and low- and intermediate-level waste (L/ILW) to gas generation is generally small. In ILW emplacement caverns, gas generation is generally dominated by hydrogen generation from the corrosion of cast iron Mosaik-II waste containers for PWR internals and from the corrosion of aluminium in operational waste from the

  18. Modelling of gas generation in deep geological repositories after closure

    Energy Technology Data Exchange (ETDEWEB)

    Poller, A. [National Cooperative for the Disposal of Radioactive Waste (NAGRA), Wettingen (Switzerland); Mayer, G.; Darcis M [AF-Consult Switzerland Ltd, Baden-Dättwil, (Switzerland); Smith, P. [Safety Assessment Management Ltd, Henley-On-Thames, Oxfordshire (United Kingdom)

    2016-12-15

    In deep geological repositories for radioactive waste, significant quantities of gases will be generated in the long term as a result of various processes, notably the anaerobic corrosion of metals and the degradation of organic materials. Therefore, the impact of gas production on post-closure safety of the repositories needs to be assessed as part of a safety case. The present report provides a comprehensive description of the quantitative modelling of gas generation and associated water consumption during the post-closure phase of deep geological repositories in Opalinus Clay based on current scientific knowledge and on current preliminary repository designs. This includes a presentation of the modelling basis, namely the conceptual and mathematical models, the input data used, the computer tools developed, the relevant uncertainties and principal programme / design options, as well as the derivation, analysis and discussion of specific assessment cases. The modelling is carried out separately for the two main sources of gas, which are the emplaced waste including the disposal containers; and the construction materials. The contribution of construction materials to gas generation rates in emplacement tunnels for spent fuel (SF) and vitrified high-level waste (HLW) is significant during several thousand years after closure. In the long term, however, the corrosion of the disposal canisters, which are in the reference case assumed to be fabricated of carbon steel, accounts for the vast majority of the total gas produced in these tunnels. The contribution of construction materials in emplacement caverns for long lived intermediate-level waste (ILW) and low- and intermediate-level waste (L/ILW) to gas generation is generally small. In ILW emplacement caverns, gas generation is generally dominated by hydrogen generation from the corrosion of cast iron Mosaik-II waste containers for PWR internals and from the corrosion of aluminium in operational waste from the

  19. Methodology developed at the CEA/IPSN for logn term performance assessment of nuclear waste repositories in geological formations

    International Nuclear Information System (INIS)

    Raimbault, P.; Lewi, J.

    1985-05-01

    The CEA/ISPN is currently developing a methodology for safety evaluation of disposal site projects in granite, clay and bedded salt, host rocks formations. In the Institute of Protection and Nuclear Safety, the Department of Safety Analysis (DAS) is responsible for the coordination of the modeling effort which is performed in several specialized groups. The models are commissionned and utilized at the IPSN for specific safety evaluations. They are improved as needed and validated through international exercices (INTRACOIN-HYDROCOIN-ATKINS) and experimental programs. The DAS develops as well a global performance assessment code named MELODIE which structure allows to couple the individual models. This code participates to international joint studies such as PAGIS, in order to test its ability to model specific sites. This should help to control the adequation of the individual models to the risk assessment evaluation in order to insure the availability of specific data and to identify the most sensitive parameters. This approach should allow to coordinate the action between experimentation, code development and safety rules determination in order to be ready to perform safety assessment on chosen sites. The current status of the different aspects of this work is presented. The model development concerns mainly: transport, hydrogeology, source term, dose calculation and sensitivity studies. Its connection with data collection and model validation is stressed in the field of source modeling, hydrogeology, geochemistry and geoprospective. The description of the first version of MELODIE is presented. Some results of the interactive evaluation of the source term, the groundwater flow and the transport of radionuclides in a granite site are presented as well

  20. The application of geological computer modelling systems to the characterisation and assessment of radioactive waste repositories

    International Nuclear Information System (INIS)

    White, M.J.; Del Olmo, C.

    1996-01-01

    The deep disposal of radioactive waste requires the collection and analysis of large amounts of geological data. These data give information on the geological and hydrogeological setting of repositories and research sites, including the geological structure and the nature of the groundwater. The collection of these data is required in order to develop an understanding of the geology and the geological evolution of sites and to provide quantitative information for performance assessments. An integrated approach to the interpretation and provision of these data is proposed in this paper, via the use of computer systems, here termed geological modelling systems. Geological modelling systems are families of software programmes which allow the incorporation of site investigation data into integrated 3D models of sub-surface geology

  1. International Conference on Geological Repositories 2016. Conference Synthesis, 7-9 December 2016, Paris, France

    International Nuclear Information System (INIS)

    Walke, Russell; Kwong, Gloria; )

    2017-01-01

    Worldwide consensus exists within the international community that geological repositories can provide the necessary long-term safety and security to isolate long-lived radioactive waste from the human environment over long timescales. Such repositories are also feasible to construct using current technologies. However, proving the technical merits and safety of repositories, while satisfying societal and political requirements, has been a challenge in many countries. Building upon the success of previous conferences held in Denver (1999), Stockholm (2003), Berne (2007) and Toronto (2012), the ICGR 2016 brought together high-level decision makers from regulatory and local government bodies, waste management organisations and public stakeholder communities to review current perspectives of geological repository development. This publication provides a synthesis of the 2016 conference on continued engagement and safe implementation of repositories, which was designed to promote information and experience sharing, particularly in the development of polices and regulatory frameworks. Repository safety, and the planning and implementation of repository programs with societal involvement, as well as ongoing work within different international organisations, were also addressed at the conference. (authors)

  2. Three-dimensional Geological and Geo-mechanical Modelling of Repositories for Nuclear Waste Disposal in Deep Geological Structures

    International Nuclear Information System (INIS)

    Fahland, Sandra; Hofmann, Michael; Bornemann, Otto; Heusermann, Stefan

    2008-01-01

    To prove the suitability and safety of underground structures for the disposal of radioactive waste extensive geo-scientific research and development has been carried out by BGR over the last decades. Basic steps of the safety analysis are the geological modelling of the entire structure including the host rock, the overburden and the repository geometry as well as the geo-mechanical modelling taking into account the 3-D modelling of the underground structure. The geological models are generated using the special-construction openGEO TM code to improve the visualisation an d interpretation of the geological data basis, e.g. borehole, mine, and geophysical data. For the geo-mechanical analysis the new JIFE finite-element code has been used to consider large 3-D structures with complex inelastic material behaviour. To establish the finite-element models needed for stability and integrity calculations, the geological models are simplified with respect to homogenous rock layers with uniform material behaviour. The modelling results are basic values for the evaluation of the stability of the repository mine and the long-term integrity of the geological barrier. As an example of application, the results of geological and geo-mechanical investigations of the Morsleben repository based on 3-D modelling are presented. (authors)

  3. Safeguarding of spent fuel conditioning and disposal in geological repositories

    International Nuclear Information System (INIS)

    Forsstroem, H.; Richter, B.

    1997-01-01

    Disposal of spent nuclear fuel in geological formations, without reprocessing, is being considered in a number of States. Before disposal the fuel will be encapsulated in a tight and corrosion resistant container. The method chosen for disposal and the design of the repository will be determined by the geological conditions and the very strict requirements on long-term safety. From a safeguards perspective spent fuel disposal is a new issue. As the spent fuel still contains important amounts of material under safeguards and as it can not be considered practicably irrecoverable in the repository, the IAEA has been advised not to terminate safeguards, even after closure of the repository. This raises a number of new issues where there could be a potential conflict of interests between safety and safeguards demands, in particular in connection with the safety principle that burdens on future generations should be avoided. In this paper some of these issues are discussed based on the experience gained in Germany and Sweden about the design and future operation of encapsulation and disposal facilities. The most important issues are connected to the required level of safeguards for a closed repository, the differences in time scales for waste management and safeguards, the need for verification of the fissile content in the containers and the possibility of retrieving the fuel disposed of. (author)

  4. Evaluation of Five Sedimentary Rocks Other Than Salt for Geologic Repository Siting Purposes

    Energy Technology Data Exchange (ETDEWEB)

    Croff, A.G.; Lomenick, T.F.; Lowrie, R.S.; Stow, S.H.

    2003-11-15

    The US Department of Energy (DOE), in order to increase the diversity of rock types under consideration by the geologic disposal program, initiated the Sedimary ROck Program (SERP), whose immediate objectiv eis to evaluate five types of secimdnary rock - sandstone, chalk, carbonate rocks (limestone and dolostone), anhydrock, and shale - to determine the potential for siting a geologic repository. The evaluation of these five rock types, together with the ongoing salt studies, effectively results in the consideration of all types of relatively impermeable sedimentary rock for repository purposes. The results of this evaluation are expressed in terms of a ranking of the five rock types with respect to their potential to serve as a geologic repository host rock. This comparative evaluation was conducted on a non-site-specific basis, by use of generic information together with rock evaluation criteria (RECs) derived from the DOE siting guidelines for geologic repositories (CFR 1984). An information base relevant to rock evaluation using these RECs was developed in hydrology, geochemistry, rock characteristics (rock occurrences, thermal response, rock mechanics), natural resources, and rock dissolution. Evaluation against postclosure and preclosure RECs yielded a ranking of the five subject rocks with respect to their potential as repository host rocks. Shale was determined to be the most preferred of the five rock types, with sandstone a distant second, the carbonate rocks and anhydrock a more distant third, and chalk a relatively close fourth.

  5. Evaluation of Five Sedimentary Rocks Other Than Salt for Geologic Repository Siting Purposes

    International Nuclear Information System (INIS)

    Croff, A.G.; Lomenick, T.F.; Lowrie, R.S.; Stow, S.H.

    2003-01-01

    The US Department of Energy (DOE), in order to increase the diversity of rock types under consideration by the geologic disposal program, initiated the Sedimary ROck Program (SERP), whose immediate objectiv eis to evaluate five types of secimdnary rock - sandstone, chalk, carbonate rocks (limestone and dolostone), anhydrock, and shale - to determine the potential for siting a geologic repository. The evaluation of these five rock types, together with the ongoing salt studies, effectively results in the consideration of all types of relatively impermeable sedimentary rock for repository purposes. The results of this evaluation are expressed in terms of a ranking of the five rock types with respect to their potential to serve as a geologic repository host rock. This comparative evaluation was conducted on a non-site-specific basis, by use of generic information together with rock evaluation criteria (RECs) derived from the DOE siting guidelines for geologic repositories (CFR 1984). An information base relevant to rock evaluation using these RECs was developed in hydrology, geochemistry, rock characteristics (rock occurrences, thermal response, rock mechanics), natural resources, and rock dissolution. Evaluation against postclosure and preclosure RECs yielded a ranking of the five subject rocks with respect to their potential as repository host rocks. Shale was determined to be the most preferred of the five rock types, with sandstone a distant second, the carbonate rocks and anhydrock a more distant third, and chalk a relatively close fourth.

  6. Site selection for deep geologic repositories - Consequences for society, economy and environment

    International Nuclear Information System (INIS)

    2010-03-01

    In a few years, Switzerland will make the decision regarding site selection for geological underground repositories for the storage of radioactive wastes. Besides the safety issue, many citizens are interested in how such a repository will affect environment, economy and society in the selected site's region. This brochure summarizes the results of many studies on the socio-economic impacts of nuclear waste repositories. Radioactive wastes must be stored in such a way that mankind and environment are safely protected for a long period of time. How this goal may be achieved, is already known: geologic deep repositories warrant long-term safety. For the oncoming years in Switzerland the question is where the repository will be built. The search for an appropriate site for a repository in the proposed regions will launch discussions. Within the participative framework the regions may bring their requests. The demonstration of the safety of potential repository sites has the highest priority in the selection process. In the third procedural step additional rock investigations will be made. The socio-economic studies and the experience with existing plants show that radioactive waste management plants can be built and operated in good agreement with environmental requirements. The radioactive wastes in a deep underground repository are stored many hundred meters below the Earth's surface. There, they are isolated from our vital space. Technical barriers and the surrounding dense rock confinement prevent the release of radioactive materials into the environment. A deep repository has positive consequences for the regional economy. It increases trade and value creation and creates work places. The socio-economic impacts practically extend over one century, but strongly vary with time; they are the largest during the building period. High life quality and a positive population development in the selected site region are compatible with a deep repository. A fair and

  7. Overly Honest Data Repository Development

    Directory of Open Access Journals (Sweden)

    Colleen Fallaw

    2016-10-01

    Full Text Available After a year of development, the library at the University of Illinois at Urbana-Champaign has launched a repository, called the Illinois Data Bank (https://databank.illinois.edu/, to provide Illinois researchers with a free, self-serve publishing platform that centralizes, preserves, and provides persistent and reliable access to Illinois research data. This article presents a holistic view of development by discussing our overarching technical, policy, and interface strategies. By openly presenting our design decisions, the rationales behind those decisions, and associated challenges this paper aims to contribute to the library community's work to develop repository services that meet growing data preservation and sharing needs.

  8. Evolution of waste-package design at the potential U.S. geologic repository

    International Nuclear Information System (INIS)

    Benton, H.; Harkins, B.

    2000-01-01

    This paper describes the evolution of the waste-package design at the potential geologic repository for spent nuclear fuel and high-level waste at Yucca Mountain in Nevada. Because the potential repository is the first of its kind, the design of its components must be flexible and capable of evolving in response to continuing scientific study, development efforts, and changes to performance criteria. The team of scientists and engineers at the Yucca Mountain Project has utilized a systematic, scientific approach to design the potential geologic nuclear-waste repository. As a result of continuing development efforts, the design has incorporated a growing base of scientific and engineering information to ensure that regulatory and performance requirements are met. (authors)

  9. Proposals of geological sites for L/ILW and HLW repositories. Geological background. Text volume

    International Nuclear Information System (INIS)

    2008-01-01

    On April 2008, the Swiss Federal Council approved the conceptual part of the Sectoral Plan for Deep Geological Repositories. The Plan sets out the details of the site selection procedure for geological repositories for low- and intermediate-level waste (L/ILW) and high-level waste (HLW). It specifies that selection of geological siting regions and sites for repositories in Switzerland will be conducted in three stages, the first one (the subject of this report) being the definition of geological siting regions within which the repository projects will be elaborated in more detail in the later stages of the Sectoral Plan. The geoscientific background is based on the one hand on an evaluation of the geological investigations previously carried out by Nagra on deep geological disposal of HLW and L/ILW in Switzerland (investigation programmes in the crystalline basement and Opalinus Clay in Northern Switzerland, investigations of L/ILW sites in the Alps, research in rock laboratories in crystalline rock and clay); on the other hand, new geoscientific studies have also been carried out in connection with the site selection process. Formulation of the siting proposals is conducted in five steps: A) In a first step, the waste inventory is allocated to the L/ILW and HLW repositories; B) The second step involves defining the barrier and safety concepts for the two repositories. With a view to evaluating the geological siting possibilities, quantitative and qualitative guidelines and requirements on the geology are derived on the basis of these concepts. These relate to the time period to be considered, the space requirements for the repository, the properties of the host rock (depth, thickness, lateral extent, hydraulic conductivity), long-term stability, reliability of geological findings and engineering suitability; C) In the third step, the large-scale geological-tectonic situation is assessed and large-scale areas that remain under consideration are defined. For the L

  10. 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)

  11. Site characterization information needs for a high-level waste geologic repository

    International Nuclear Information System (INIS)

    Gupta, D.C.; Nataraja, M.S.; Justus, P.S.

    1987-01-01

    At each of the three candidate sites recommended for site characterization for High-Level Waste Geologic Repository development, the DOE has proposed to conduct both surface-based testing and in situ exploration and testing at the depths that wastes would be emplaced. The basic information needs and consequently the planned surface-based and in situ testing program will be governed to a large extent by the amount of credit taken for individual components of the geologic repository in meeting the performance objectives and siting criteria. Therefore, identified information to be acquired from site characterization activities should be commensurate with DOE's assigned performance goals for the repository system components on a site-specific basis. Because of the uncertainties that are likely to be associated with initial assignment of performance goals, the information needs should be both reasonably and conservatively identified

  12. Natural analogues: studies of geological processes relevant to radioactive waste disposal in deep geological repositories

    Energy Technology Data Exchange (ETDEWEB)

    Russel, A.W. [Bedrock Geosciences, Auenstein (Switzerland); Reijonen, H.M. [Saanio and Rickkola Oy, Helsinki (Finland); McKinley, I.G. [MCM Consulting, Baden-Daettwil (Switzerland)

    2015-06-15

    The geological disposal of radioactive wastes is generally accepted to be the most practicable approach to handling the waste inventory built up from over 70 years accumulation of power production, research-medical-industrial and military wastes. Here, a brief overview of the approach to geological disposal is presented along with some information on repository design and the assessment of repository post-closure safety. One of the significant challenges for repository safety assessment is how to extrapolate the likely long-term (i.e. ten thousand to a million years) behaviour of the repository from the necessarily short term data from analytical laboratories and underground rock laboratories currently available. One approach, common to all fields of the geosciences, but also in such diverse fields as philosophy, biology, linguistics, law, etc., is to utilise the analogue argumentation methodology. For the specific case of radioactive waste management, the term 'natural analogue' has taken on a particular meaning associated with providing supporting arguments for a repository safety assessment. This approach is discussed here with a brief overview of how the study of natural (and, in particular, geological) systems can provide supporting information on the likely long-term evolution of a deep geological waste repository. The overall approach is discussed and some relevant examples are presented, including the use of uranium ore bodies to assess waste form stability, the investigation of native metals to define the longevity of waste containers and how natural clays can provide information on the stability of waste tunnel backfill material. (authors)

  13. Natural analogues: studies of geological processes relevant to radioactive waste disposal in deep geological repositories

    International Nuclear Information System (INIS)

    Russel, A.W.; Reijonen, H.M.; McKinley, I.G.

    2015-01-01

    The geological disposal of radioactive wastes is generally accepted to be the most practicable approach to handling the waste inventory built up from over 70 years accumulation of power production, research-medical-industrial and military wastes. Here, a brief overview of the approach to geological disposal is presented along with some information on repository design and the assessment of repository post-closure safety. One of the significant challenges for repository safety assessment is how to extrapolate the likely long-term (i.e. ten thousand to a million years) behaviour of the repository from the necessarily short term data from analytical laboratories and underground rock laboratories currently available. One approach, common to all fields of the geosciences, but also in such diverse fields as philosophy, biology, linguistics, law, etc., is to utilise the analogue argumentation methodology. For the specific case of radioactive waste management, the term 'natural analogue' has taken on a particular meaning associated with providing supporting arguments for a repository safety assessment. This approach is discussed here with a brief overview of how the study of natural (and, in particular, geological) systems can provide supporting information on the likely long-term evolution of a deep geological waste repository. The overall approach is discussed and some relevant examples are presented, including the use of uranium ore bodies to assess waste form stability, the investigation of native metals to define the longevity of waste containers and how natural clays can provide information on the stability of waste tunnel backfill material. (authors)

  14. MONITORED GEOLOGIC REPOSITORY LIFE CYCLE COST ESTIMATE ASSUMPTIONS DOCUMENT

    International Nuclear Information System (INIS)

    R.E. Sweeney

    2001-01-01

    The purpose of this assumptions document is to provide general scope, strategy, technical basis, schedule and cost assumptions for the Monitored Geologic Repository (MGR) life cycle cost (LCC) estimate and schedule update incorporating information from the Viability Assessment (VA) , License Application Design Selection (LADS), 1999 Update to the Total System Life Cycle Cost (TSLCC) estimate and from other related and updated information. This document is intended to generally follow the assumptions outlined in the previous MGR cost estimates and as further prescribed by DOE guidance

  15. Monitored Geologic Repository Life Cycle Cost Estimate Assumptions Document

    International Nuclear Information System (INIS)

    Sweeney, R.

    2000-01-01

    The purpose of this assumptions document is to provide general scope, strategy, technical basis, schedule and cost assumptions for the Monitored Geologic Repository (MGR) life cycle cost estimate and schedule update incorporating information from the Viability Assessment (VA), License Application Design Selection (LADS), 1999 Update to the Total System Life Cycle Cost (TSLCC) estimate and from other related and updated information. This document is intended to generally follow the assumptions outlined in the previous MGR cost estimates and as further prescribed by DOE guidance

  16. Geologic software for nuclear waste repository studies: A quality assurance program

    International Nuclear Information System (INIS)

    Figuli, S.; English, S.L.

    1987-04-01

    This paper discusses a Quality Assurance (QA) program that Kent State University (KSU) has implemented for the development of geologic software. The software being developed at KSU will be used in the site characterization of nuclear waste repositories and must meet the requirements of federal regulations. This QA program addresses the development of models that will be used in the evaluation of the long-term climatic stability of three sites in the western US

  17. A safeguards approach for a closed geological repository for spent fuel

    International Nuclear Information System (INIS)

    Meer, K. van der; Carchon, R.

    1999-01-01

    After closure of a geological repository a diversion of fissile material can only take place by excavating spent fuel containers and bringing them to the surface. Therefore mining activities are required, either by reopening the original shaft, by creating a new shaft or by approaching the containers underground via a neighbouring mine The recovery time of the stored spent fuel plays an important role in the determination of the timeliness criterion and, therefore, the inspection frequency of the site. Obviously, this frequency can create a financial constraint due to the infinite character of the spent fuel storage in a geological repository. Anomalies for detection of a possible diversion are undeclared mining activities. The safeguards approach has to assure Continuity Of Knowledge (COK) of the fissile material. By consequence, a safeguards approach that is developed for a closed repository, is influenced by the safeguards approach applied to an open. repository and a conditioning facility. A closed repository is verified by DIV. To perform the DIV satellite monitoring could be performed for surface verification and e.g. seismic techniques could be used for verification that no undeclared mining activities underground take place. Visual inspections of the site by inspectors have to reveal concealment methods used by a potential diverter. These measures should guarantee that the disposed spent fuel remains untouched. (author)

  18. 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

  19. Stockholm international conference 2003 on geological repositories: Political and technical progress

    International Nuclear Information System (INIS)

    2004-01-01

    The conference reviewed global progress made as well as current perspectives on the activities to develop geologic repositories. The objectives were to review the progress in policy making as well as technical issues and to strengthen international co-operation on waste management and disposal issues. The first day of the conference addressed the policy aspects of geological repositories and the second day featured the more technical issues. Session 1: International progress in performing long-term safety studies and security of geological disposal were discussed and reviewed with examples from OECD/NEA, Belgium, Sweden, USA, Switzerland and Russia. Session 2: Views on stakeholder involvement and decision making process were presented by international organisations and national implementers from Japan, United Kingdom, Belgium and OECD/NEA. Session 3: Views on stakeholder involvement and decision making process were presented by regional and local stakeholders from France, Finland, Korea and Sweden. Session 4: International instruments assisting in the implementation of geological repositories were discussed, for example ICRP and IAEA/NEA safety documents, Joint Convention, Safeguard agreements, Nuclear Liability Conventions, etc. Session 5: The contribution of Research, Development and Demonstration was discussed with overviews of the progress achieved on scientific and technical issues over the past four years. Progress and key issues were presented from Switzerland, USA, Finland, Japan, Sweden and IAEA. Each of the papers and poster presentations have been analysed and indexed separately

  20. Repository development status in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Beceiro, Alvaro; Zuloaga, Pablo [ENRESA (Spain)

    2009-06-15

    The paper describes the status of repository development for the different waste categories. Low and Intermediate Waste Disposal facility of El Cabril was commissioned in 1992 and is in normal operation. The major modifications and activities during the last years are the adaptation to waste streams not initially foreseen such as some decommissioning waste or waste from steel industry, and the improvement of its performance assessment, supported by a R and D and refined models. As part of this facility, a new disposal facility specifically intended for very low activity waste has been constructed and commissioned in July 2008. Its design is based on the European Directive for hazardous waste disposal. National policy for Nuclear Spent Fuel and High-Level waste is focused on the development of a centralized storage facility of the vault type, whose site location would be selected through a volunteering process. Meanwhile, with the aim of solving specific problems, three individual storage facilities are in different status at reactor sites. Research on final solution, including some repository aspects as well as separation and transmutation are being carried out in accordance to ENRESA's R and D program. ENRESA has developed conceptual designs for non site specific repositories, both in granite and clay, and has carried out their corresponding performance assessment exercises. (authors)

  1. Geologic, stratigraphic, thermal, and mechanical factors which influence repository design in the bedded salt environment

    International Nuclear Information System (INIS)

    Ashby, J.P.; Nair, O.; Ortman, D.; Rowe, J.

    1979-12-01

    This report describes the geologic, stratigraphic, thermal, and mechanical considerations applicable to repository design. The topics discussed in the report include: tectonic activity; geologic structure; stratigraphy; rock mechanical properties; and hydrologic properties

  2. 3D numerical modelling of the thermal state of deep geological nuclear waste repositories

    Science.gov (United States)

    Butov, R. A.; Drobyshevsky, N. I.; Moiseenko, E. V.; Tokarev, Yu. N.

    2017-09-01

    One of the important aspects of the high-level radioactive waste (HLW) disposal in deep geological repositories is ensuring the integrity of the engineered barriers which is, among other phenomena, considerably influenced by the thermal loads. As the HLW produce significant amount of heat, the design of the repository should maintain the balance between the cost-effectiveness of the construction and the sufficiency of the safety margins, including those imposed on the thermal conditions of the barriers. The 3D finite-element computer code FENIA was developed as a tool for simulation of thermal processes in deep geological repositories. Further the models for mechanical phenomena and groundwater hydraulics will be added resulting in a fully coupled thermo-hydro-mechanical (THM) solution. The long-term simulations of the thermal state were performed for two possible layouts of the repository. One was based on the proposed project of Russian repository, and another features larger HLW amount within the same space. The obtained results describe the spatial and temporal evolution of the temperature filed inside the repository and in the surrounding rock for 3500 years. These results show that practically all generated heat was ultimately absorbed by the host rock without any significant temperature increase. Still in the short time span even in case of smaller amount of the HLW the temperature maximum exceeds 100 °C, and for larger amount of the HLW the local temperature remains above 100 °C for considerable time. Thus, the substantiation of the long-term stability of the repository would require an extensive study of the materials properties and behaviour in order to remove the excessive conservatism from the simulations and to reduce the uncertainty of the input data.

  3. On ocean island geological repository - a second-generation option for disposal of spent fuel and high-level waste

    International Nuclear Information System (INIS)

    Forsberg, C.W.

    1993-01-01

    The concept of an ocean subseabed geological high-level waste repository with access via an ocean island is discussed. The technical advantages include, in addition to geologic waste isolation, geographical isolation, near-zero groundwater flow through the disposal site, and near-infinite ocean dilution as a backup in the event of a failure of the repository geological waste isolation system. The institutional advantages may include reduced siting problems and the potential of creating an international waste repository. Establishment of a repository accepting wastes from many countries would allow cost sharing, aid international nonproliferation goals, and ensure proper disposal of spent fuel from developing countries. Major uncertainties that are identified in this concept are the uncertainties in rock conditions at waste disposal depths, costs, and ill-defined institutional issues

  4. 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)

  5. Radionuclide transport behavior in a generic geological radioactive waste repository.

    Science.gov (United States)

    Bianchi, Marco; Liu, Hui-Hai; Birkholzer, Jens T

    2015-01-01

    We performed numerical simulations of groundwater flow and radionuclide transport to study the influence of several factors, including the ambient hydraulic gradient, groundwater pressure anomalies, and the properties of the excavation damaged zone (EDZ), on the prevailing transport mechanism (i.e., advection or molecular diffusion) in a generic nuclear waste repository within a clay-rich geological formation. By comparing simulation results, we show that the EDZ plays a major role as a preferential flowpath for radionuclide transport. When the EDZ is not taken into account, transport is dominated by molecular diffusion in almost the totality of the simulated domain, and transport velocity is about 40% slower. Modeling results also show that a reduction in hydraulic gradient leads to a greater predominance of diffusive transport, slowing down radionuclide transport by about 30% with respect to a scenario assuming a unit gradient. In addition, inward flow caused by negative pressure anomalies in the clay-rich formation further reduces transport velocity, enhancing the ability of the geological barrier to contain the radioactive waste. On the other hand, local high gradients associated with positive pressure anomalies can speed up radionuclide transport with respect to steady-state flow systems having the same regional hydraulic gradients. Transport behavior was also found to be sensitive to both geometrical and hydrogeological parameters of the EDZ. Results from this work can provide useful knowledge toward correctly assessing the post-closure safety of a geological disposal system. © 2014, National Ground Water Association.

  6. From the repository to the deep geological repository - and back to the Terrain surface?

    International Nuclear Information System (INIS)

    Lahodynsky, R.

    2011-01-01

    How deep is 'safe'? How long is long-term? How and for how long will something be isolated? Which rock, which formation and which location are suitable? A repository constructed for the safekeeping of radioactive or highly toxic wastes can be erected either on the surface, near the surface or underground. Radioactive waste is currently often stored at near-surface locations. The storage usually takes place nearby of a nuclear power plant in pits or concrete tombs (vaults). However, repositories can also be found in restricted areas, e.g. near nuclear weapon production or reprocessing plants (WAA) or nuclear weapons test sites (including Tomsk, Russia, Hanford and Nevada desert, USA), or in extremely low rainfall regions (South Africa). In addition there are disused mines which are now used as underground repositories. Low-level and medium-active (SMA) but also high-level waste (HAA) are stored at these types of sites (NPP, WAA, test areas, former mines). In Russia (Tomsk, Siberia) liquid radioactive waste has been injected into deep geological formations for some time (Minatom, 2001). However, all these locations are not the result of a systematic, scientific search or a holistic process for finding a location, but the result of political decisions, sometimes ignoring scientific findings. Why underground storage is given preference over high-security landfill sites (HSD) often has economic reasons. While a low safety standard can significantly reduce the cost of an above-ground high-security landfill as a waste disposal depot, spending remains high, especially due to the need for capital formation to cover operating expenses after filling the HSD. In the case of underground storage, on the other hand, no additional expenses are required for the period after backfilling. The assumption of lower costs for a deep repository runs through the past decades and coincides with the assumption that the desired ideal underground conditions actually exist and will

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

    International Nuclear Information System (INIS)

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

    2009-11-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-11-15

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

  9. Handling encapsulated spent fuel in a geologic repository environment

    International Nuclear Information System (INIS)

    Ballou, L.B.

    1983-02-01

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

  10. Site selection factors for repositories of solid high-level and alpha-bearing wastes in geological formations

    International Nuclear Information System (INIS)

    1977-01-01

    The purpose of this report is to provide guidelines for the selection and evaluation of suitable areas and sites for the disposal of solid high-level and alpha-bearing wastes into geological formations. This report is also intended to provide summary information on many types of geological formations underlying the land masses that might be considered as well as guidance on the geological and hydrological factors that should be investigated to demonstrate the suitability of the formations. In addition, other factors that should be considered in selecting a site for a radioactive waste repository are discussed briefly. The information, as presented, was developed to the extent of current technology for application to the evaluation of deep (greater than about 300 metres below ground level) geological formations in the selection of suitable areas for the disposal of solid or solidified high-level and alpha-bearing wastes. The extreme complexity of many geological environments and of the rock features that govern the presence and circulation of groundwater does not make it feasible to derive strict criteria for the selection of a site for a radioactive waste repository in a geological formation. Each potential repository location must be evaluated according to its own unique geological and hydrological setting. Therefore, only general guidance is offered, and this is done through discussion of the many factors that need to be considered in order to obtain the necessary assurances that the radionuclides will be confined in the geological repository over the required period of time

  11. Site selection factors for repositories of solid high-level and alpha-bearing wastes in geological formations

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    The purpose of this report is to provide guidelines for the selection and evaluation of suitable areas and sites for the disposal of solid high-level and alpha-bearing wastes into geological formations. This report is also intended to provide summary information on many types of geological formations underlying the land masses that might be considered as well as guidance on the geological and hydrological factors that should be investigated to demonstrate the suitability of the formations. In addition, other factors that should be considered in selecting a site for a radioactive waste repository are discussed briefly. The information, as presented, was developed to the extent of current technology for application to the evaluation of deep (greater than about 300 meters below ground level) geological formations in the selection of suitable areas for the disposal of solid or solidified high-level and alpha-bearing wastes. The extreme complexity of many geological environments and of the rock features that govern the presence and circulation of groundwater does not make it feasible to derive strict criteria for the selection of a site for a radioactive waste repository in a geological formation. Each potential repository location must be evaluated according to its own unique geological and hydrological setting. Therefore, only general guidance is offered, and this is done through discussion of the many factors that need to be considered in order to obtain the necessary assurances that the radionuclides will be confined in the geological repository over the required period of time.

  12. Geotechnical support and topical studies for nuclear waste geologic repositories

    International Nuclear Information System (INIS)

    1989-01-01

    The present report lists the technical reviews and comments made during the fiscal year 1988 and summarizes the technical progress of the topical studies. In the area of technical assistance, there were numerous activities detailed in the next section. These included 24 geotechnical support activities, including reviews of 6 Study Plans (SP) and participation in 6 SP Review Workshops, review of one whole document Site Characterization Plan (SCP) and participation in the Assembled Document SCP Review Workshops by 6 LBL reviewers; the hosting of a DOE program review, the rewriting of the project statement of work, 2 trips to technical and planning meetings; preparation of proposed work statements for two new topics for DOE, and 5 instances of technical assistance to DOE. These activities are described in a Table in the following section entitled ''Geoscience Technical Support for Nuclear Waste Geologic Repositories.''

  13. Experiments on thermal conductivity in buffer materials for geologic repository

    International Nuclear Information System (INIS)

    Kanno, T.; Yano, T.; Wakamatsu, H.; Matsushima, E.

    1989-01-01

    Engineered barriers for geologic disposal for HLW are planned to consist of canister, overpack and buffer elements. One of important physical characteristics of buffer materials is determining temperature profiles within the near field in a repository. Buffer materials require high thermal conductivity to disperse radiogenic heat away to the host rock. As the buffer materials, compacted blocks of the mixture of sodium bentonite and sand have been the most promising candidate in some countries, e.g. Sweden, Switzerland and Japan. The authors have been carrying out a series of thermal dispersion experiments to evaluate thermal conductivity of bentonite/quartz sand blocks. In this study, the following two factors considered to affect thermal properties of the near field were examined: effective thermal conductivities of buffer materials, and heat transfer characteristics of the gap between overpack and buffer materials

  14. A Rock Mechanics and Coupled Hydro mechanical Analysis of Geological Repository of High Level Nuclear Waste in Fractured Rocks

    International Nuclear Information System (INIS)

    Min, Kibok

    2011-01-01

    This paper introduces a few case studies on fractured hard rock based on geological data from Sweden, Korea is one of a few countries where crystalline rock is the most promising rock formation as a candidate site of geological repository of high level nuclear waste. Despite the progress made in the area of rock mechanics and coupled hydro mechanics, extensive site specific study on multiple candidate sites is essential in order to choose the optimal site. For many countries concerned about the safe isolation of nuclear wastes from the biosphere, disposal in a deep geological formation is considered an attractive option. In geological repository, thermal loading continuously disturbs the repository system in addition to disturbances a recent development in rock mechanics and coupled hydro mechanical study using DFN(Discrete Fracture Network) - DEM(Discrete Element Method) approach mainly applied in hard, crystalline rock containing numerous fracture which are main sources of deformation and groundwater flow

  15. LISA: A performance assessment code for geological repositories of radioactive waste

    International Nuclear Information System (INIS)

    Bertozzi, G.; Saltelli, A.

    1985-01-01

    LISA, developed at JRC-Ispra, is a statistical code, which calculates the radiation exposures and risks associated with radionuclide releases from geological repositories of nuclear waste. The assessment methodology is described briefly. It requires that a number of probabilistic components be quantified and introduced in the analysis; the results are thus expressed in terms of risk. The subjective judgment of experts may be necessary to quantify the probabilities of occurrence of rare geological events. Because of large uncertainties in input data, statistical treatment of the Monte Carlo type is utilized for the analysis; thus, the output from LISA is obtained in the form of distributions. A few results of an application to a probabilistic scenario for a repository mined in a clay bed are illustrated

  16. Parameters and criteria influencing the selection of waste emplacement configurations in mined geologic repositories

    International Nuclear Information System (INIS)

    Bechthold, W.; Closs, K.D.; Papp, R.

    1988-01-01

    Reference concepts for repositories in deep geological formations have been developed in several countries. For these concepts, emplacement configurations vary within a wide range that comprises drift emplacement of unshielded or self-shielded packages and horizontal or vertical borehole emplacement. This is caused by different parameters, criteria, and criteria weighting factors. Examples for parameters are the country's nuclear power program and waste management policy, its geological situation, and safety requirements, examples for criteria and repository area requirements, expenditures of mining and drilling, and efforts for emplacement and, if required, retrieval. Due to the variety of these factors and their ranking in different countries, requirements for a safe, dependable and cost-effective disposal of radioactive waste can be met in various ways

  17. Key radionuclides and parameters that determine performance of geologic repositories for high-level radioactive wastes

    International Nuclear Information System (INIS)

    Joonhong Ahn; Atsuyuki Suzuki

    1993-01-01

    This paper presents results of a mathematical analysis for performance of the engineered barriers of high-level radioactive waste repositories. The main body of the mathematical model developed in this study is mass transport of actinides in a bentonite region. In an analysis of actinide transport, radioactive decay chain and effects of low solubilities must be taken into account. In many previous models for mass transport in engineered barriers including radioactive decay chain, however, boundary conditions at the interface between the waste form and the bentonite region cannot be determined flexibly. In some models, solubility-limited boundary condition is assumed for all the members in a chain. In order to investigate what are key radionuclides and parameters that control performance of engineered barriers of a geologic repository, we must evaluate mass transport with the source boundary condition determined by a detailed analysis on mass transfer at the boundary. In this study, we developed a mathematical model, which can determine whether the inner boundary condition is solubility-limited or congruent release, based on a mathematical analysis for mass transfer at the glass dissolution location, and how long the solubility-limited boundary condition applies. Based on the mathematical model, we point out radionuclides and parameters that have primary influences on the performance of a repository, and investigate a reasonable strategy for coupling geologic disposal and partitioning of those key radionuclides from the standpoint of reducing hazard of geologic disposal. (authors). 4 tabs., 2 figs., 8 refs

  18. Plans for characterization of the potential geologic repository site at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Dobson, D.C.; Blanchard, M.B.; Voegele, M.D.; Younker, J.L.

    1990-01-01

    Site investigations in the vicinity of the potential repository site at Yucca Mountain, Nevada, have occurred for many years. Although information from previous site investigations was adequate to support preliminary evaluations by the US Department of Energy (DOE) in the Environmental Assessment and to develop conceptual repository and waste package designs, this information is insufficient to proceed to the advanced designs and performance assessments required for the license application to the US Nuclear Regulatory Commission (NRC). Therefore, intensive site characterization is planned, as described in the December 1988 Site Characterization Plan (SCP). The data acquisition activities described in the SCP are focused on obtaining information to allow evaluations of the natural and engineered barriers considered potentially relevant to repository performance. The site data base must be adequate to allow predictions of the range of expected variation in geologic conditions over the next 10,000 years, as well as predictions of the probabilities for catastrophic geologic events that could affect repository performance. 4 refs., 4 figs

  19. 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

  20. Parametric study of geohydrologic performance characteristics for geologic waste repositories

    International Nuclear Information System (INIS)

    Bailey, C.E.; Marine, I.W.

    1980-11-01

    One of the major objectives of the National Waste Terminal Storage Program is to identify potential geologic sites for storage and isolation of radioactive waste (and possibly irradiated fuel). Potential sites for the storage and isolation of radioactive waste or spent fuel in a geologic rock unit are being carefully evaluated to ensure that radionuclides from the stored waste or fuel will never appear in the biosphere in amounts that would constitute a hazard to the health and safety of the public. The objective of this report is to quantify and present in graphical form the effects of significant geohydrologic and other performance characteristics that would influence the movement of radionuclides from a storage site in a rock unit to the biosphere. The effort in this study was focused on transport by groundwater because that is the most likely method of radionuclide escape. Graphs of the major performance characteristics that influence the transport of radionuclides from a repository to the biosphere by groundwater are presented. The major characteristics addressed are radioactive decay, leach rate, hydraulic conductivity, porosity, groundwater gradient, hydrodynamic dispersion, ion exchange, and distance to the biosphere. These major performance characteristics are combind with each other and with the results of certain other combinations and presented in graphical form to provide the interrelationships of values measured during field studies. The graphical form of presentation should be useful in the screening process of site selection. An appendix illustrates the use of these graphs to assess the suitability of a site

  1. Groundwater movements around a repository. Geological and geotechnical conditions

    International Nuclear Information System (INIS)

    Stille, H.; Burgess, A.; Lindblom, U.E.

    1977-09-01

    The report was prepared as one of a series of technical reports within a study of the groundwater movements around a repository for radioactive waste in the Precambrian bedrock of Sweden. This assessment is intended to provide basic geotechnical data for the analysis. These data include properties and conditions that are representative of the intact rock, the rock mass in general, and the groundwater regime. As there exist a considerable range in the mineralogy of potentially suitable plutonic rocks and since a specific site has not yet been selected, all of the parameters presented in this report must be based on presumptive geological and hydrogeological conditions. Where possible, data for two potential site areas, namely Oskarshamn and Forsmark, are presented. This report is divided into four parts. First, a brief description of the procedure for modelling groundwater movements is presented, along with a tabulation of the important parameters. Secondly, a description of the geological and hydrogeological conditions of the Fennoscandian shield, as well as of the two general site areas, is given. The final two sections of the report provide thermomechanical and geohydrological characteristics and properties of the host rock

  2. Geological status of NWTS repository siting activities in the paradox basin

    International Nuclear Information System (INIS)

    Frazier, N.A.; Conwell, F.R.

    1981-01-01

    Emplacement of waste packages in mined geological repositories is one method being evaluated for isolating high-level nuclear wastes. Granite, dome salt, tuff, basalt and bedded salt are among the rock types being investigated. Described in this paper is the status of geological activities in the Paradox Basin of Utah and Colorado, one region being explored as a part of the National Waste Terminal Storage (NWTS) program to site a geological repository in bedded salt

  3. Center for Leadership Development (CLD) Repository

    Data.gov (United States)

    Office of Personnel Management — The Center for Leadership Development Repository stores various data including policies, procedures, governance, guidance, security, and financial documents of the...

  4. Displays for promotion of public understanding of geological repository concept and the spatial scale

    International Nuclear Information System (INIS)

    Shobu, Nobuhiro; Kashiwazaki, Hiroshi

    2003-05-01

    Japan Nuclear Cycle Development Institutes (JNC) has a few thousands of short term visitors to Geological Isolation Basic Research Facility of Tokai works in every year. From the viewpoint of promotion of the visitor's understanding and also smooth communication between researchers and visitors, the explanation of the technical information on geological disposal should be carried out in more easily understandable methods, as well as conventional tour to the engineering-scale test facility (ENTRY). This paper reports on the background information and the appearance of displays, which were installed at ENTRY, to promote public understanding of geological repository concept and the spatial scale. They have been practically used as one of the explanation tools to support visitor's understanding. (author)

  5. Use of Groundwater Lifetime Expectancy for the Performance Assessment of Deep Geologic Radioactive Waste Repositories.

    Science.gov (United States)

    Cornaton, F.; Park, Y.; Normani, S.; Sudicky, E.; Sykes, J.

    2005-12-01

    Long-term solutions for the disposal of toxic wastes usually involve isolation of the wastes in a deep subsurface geologic environment. In the case of spent nuclear fuel, the safety of the host repository depends on two main barriers: the engineered barrier and the natural geological barrier. If radionuclide leakage occurs from the engineered barrier, the geological medium represents the ultimate barrier that is relied upon to ensure safety. Consequently, an evaluation of radionuclide travel times from the repository to the biosphere is critically important in a performance assessment analysis. In this study, we develop a travel time framework based on the concept of groundwater lifetime expectancy as a safety indicator. Lifetime expectancy characterizes the time radionuclides will spend in the subsurface after their release from the repository and prior to discharging into the biosphere. The probability density function of lifetime expectancy is computed throughout the host rock by solving the backward-in-time solute transport equation subject to a properly posed set of boundary conditions. It can then be used to define optimal repository locations. In a second step, the risk associated with selected sites can be evaluated by simulating an appropriate contaminant release history. The proposed methodology is applied in the context of a typical Canadian Shield environment. Based on a statistically-generated three-dimension network of fracture zones embedded in the granitic host rock, the sensitivity and the uncertainty of lifetime expectancy to the hydraulic and dispersive properties of the fracture network, including the impact of conditioning via their surface expressions, is computed in order to demonstrate the utility of the methodology.

  6. Engineered barrier system and waste package design concepts for a potential geologic repository at Yucca Mountain

    International Nuclear Information System (INIS)

    Short, D.W.; Ruffner, D.J.; Jardine, L.J.

    1991-10-01

    We are using an iterative process to develop preliminary concept descriptions for the Engineered Barrier System and waste-package components for the potential geologic repository at Yucca Mountain. The process allows multiple design concepts to be developed subject to major constraints, requirements, and assumptions. Involved in the highly interactive and interdependent steps of the process are technical specialists in engineering, metallic and nonmetallic materials, chemistry, geomechanics, hydrology, and geochemistry. We have developed preliminary design concepts that satisfy both technical and nontechnical (e.g., programmatic or policy) requirements

  7. Staff Technical Position on geological repository operations area underground facility design: Thermal loads

    International Nuclear Information System (INIS)

    Nataraja, M.S.

    1992-12-01

    The purpose of this Staff Technical Position (STP) is to provide the US Department of Energy (DOE) with a methodology acceptable to the Nuclear Regulatory Commission staff for demonstrating compliance with 10 CFR 60.133(i). The NRC staff's position is that DOE should develop and use a defensible methodology to demonstrate the acceptability of a geologic repository operations area (GROA) underground facility design. The staff anticipates that this methodology will include evaluation and development of appropriately coupled models, to account for the thermal, mechanical, hydrological, and chemical processes that are induced by repository-generated thermal loads. With respect to 10 CFR 60.133(i), the GROA underground facility design: (1) should satisfy design goals/criteria initially selected, by considering the performance objectives; and (2) must satisfy the performance objectives 10 CFR 60.111, 60.112, and 60.113. The methodology in this STP suggests an iterative approach suitable for the underground facility design

  8. Geologic repositories for radioactive waste: the nuclear regulatory commission geologic comments on the environmental assessment

    International Nuclear Information System (INIS)

    Justus, P.S.; Trapp, J.S.; Westbrook, K.B.; Lee, R.; Blackford, M.B.; Rice, B.

    1985-01-01

    The NRC staff completed its review of the Environmental Assessments (EAs) issued by the Department of Energy (DOE) in December, 1984, in support of the site selection processes established by the Nuclear Waste Policy Act of 1982 (NWPA). The EAs contain geologic information on nine sites that DOE has identified as potentially acceptable for the first geologic repository in accordance with the requirements of NWPA. The media for the sites vary from basalt at Hanford, Washington, tuff at Yucca Mountain, Nevada, bedded salt in the Palo Duro Basin, Texas and Paradox Basin, Utah, to salt domes in Mississippi and Louisiana. Despite the diversity in media there are common areas of concern for all sites. These include; structural framework and pattern, rates of tectonic and seismic activity, characterization of subsurface features, and stratigraphic thickness, continuity and homogeneity. Site-specific geologic concerns include: potential volcanic and hydrothermal activity at Yucca Mountain, potential hydrocarbon targets and deep basalt and sub-basalt structure at Hanford, and potential dissolution at all salt sites. The NRC comments were influenced by the performance objectives and siting criteria of 10 CFR Part 60 and the environmental protection criteria in 40 CFR Part 191, the applicable standards proposed by EPA. In its review the NRC identified several areas of geologic concern that it recommended DOE re-examine to determine if alternative or modified conclusions are appropriate

  9. 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

  10. 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)

  11. Geological repositories: The last nuclear frontier. International Conference on Geological Repositories: Political and Technical Progress, 8-10 December 2003, Stockholm, Sweden

    International Nuclear Information System (INIS)

    ElBaradei, M.

    2003-01-01

    Few issues play so central a role in the public acceptance of nuclear technologies as the management and disposal of spent fuel and radioactive waste. In the current climate, geological repositories have come to be viewed not as one option among many for completing the nuclear fuel cycle, but as the only sustainable solution achievable in the near term. But despite a longstanding agreement among experts that geological disposal can be safe, technologically feasible and environmentally sound, a large part of the general public remains skeptical. This statement deals with the challenges that IAEA is facing to build public confidence related to spent fuel repositories

  12. 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

  13. 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...

  14. Proceedings of the workshop on radionuclide release scenarios for geologic repositories

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    The safety of radioactive waste disposal in geological formations cannot be verified experimentally. Safety analysis provides the only means to ensure that all risks associated with the waste repositories are acceptably low. The definition of radionuclide release scenarios, as discussed in these proceeedings, is the first step in the safety analysis of waste repositories.

  15. Deep geologic repository for low and intermediate radioactive level waste in Canada

    International Nuclear Information System (INIS)

    Liu Jianqin; Li Honghui; Sun Qinghong; Yang Zhongtian

    2012-01-01

    Ontario Power Generation (OPG) is undergoing a project for the long-term management of low and intermediate level waste (LILW)-a deep geologic repository (DGR) project for low and intermediate level waste. The waste source term disposed, geologic setting, repository layout and operation, and safety assessment are discussed. It is expected to provide reference for disposal of low and intermediate level waste that contain the higher concentration of long-lived radionuclides in China. (authors)

  16. 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

  17. Site descriptive modelling during characterization for a geological repository for nuclear waste in Sweden

    International Nuclear Information System (INIS)

    Stroem, A.; Andersson, J.; Skagius, K.; Winberg, A.

    2008-01-01

    The Swedish programme for geological disposal of spent nuclear fuel is approaching major milestones in the form of permit applications for an encapsulation plant and a deep geologic repository. This paper presents an overview of the bedrock and surface modelling work that comprises a major part of the on-going site characterization in Sweden and that results in syntheses of the sites, called site descriptions. The site description incorporates descriptive models of the site and its regional setting, including the current state of the geosphere and the biosphere as well as natural processes affecting long-term evolution. The site description is intended to serve the needs of both repository engineering with respect to layout and construction, and safety assessment, with respect to long-term performance. The development of site-descriptive models involves a multi-disciplinary interpretation of geology, rock mechanics, thermal properties, hydrogeology, hydrogeochemistry, transport properties and ecosystems using input in the form of available data for the surface and from deep boreholes

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

    International Nuclear Information System (INIS)

    1983-06-01

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

  19. Effect of reprocessing and recycling on the geologic repository dose rate : status

    International Nuclear Information System (INIS)

    Morris, E. E.; Nutt, W. M.; Wigeland, R. A.; Nuclear Engineering Division

    2007-01-01

    Two simplified repository performance assessment models are used to assess the impact of modeling changes in on conclusions regarding the impact of various reprocessing and recycling strategies. Waste streams from a pressurized water reactor (PWR) and a preliminary design for an advanced burner test reactor (ABTR) are used for this study of the effects on the estimated dose rate resulting from the release of radionuclides from a geologic repository. Calculations for the PWR make use of radionuclide discharge vectors for an assumed burnup of 51 GWd/MTIHM[1]. The repository is assumed to be filled with 70,000 MT of the spent fuel or with a glass waste form containing the radionuclides from 70,000 MT of spent PWR fuel. For the ABTR, the radionuclide inventory discharged at the end of an equilibrium cycle[2] is processed into a glass waste form for repository disposal, assuming actinide recovery efficiencies ranging from 90% to 99.99%. The recovered actinides are returned to the reactor. To compare with the PWR results, the repository is assumed to be filled with ABTR waste from fuel that has generated the same amount of thermal energy as 70,000 MT of the PWR fuel. The two repository performance assessment models, the first a simplified model[3] (SSR) based on the site recommendation model used by the Yucca Mountain Project (YMP)[4], and the second an updated simplified model (US) based on more recent modeling developments by the YMP are implemented in the computer simulation code GoldSim[5]. The updated model is based on a simplified model used to conduct a sensitivity analysis to evaluate factors that potentially influence performance of a repository at Yucca Mountain over the period of peak dose[6]. Factors that have either a minor or no effect on the peak dose either were not included in that simplified model or were included in a bounding representation. In the US model, enhancements were made to include some factors that have an effect on the dose occurring

  20. Developing criteria to establish Trusted Digital Repositories

    Science.gov (United States)

    Faundeen, John L.

    2017-01-01

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

  1. U.S. Department of Energy approaches to the assessment of radionuclide migration for the geologic repository program

    International Nuclear Information System (INIS)

    Luik, A.E. van; Apted, M.J.

    1988-01-01

    Potential radionuclide migration in geologic repositories is being addressed by the U.S. Department of Energy's Office of Civilian Radioactive Waste Management through its Office of Geologic Repositories (OGR). A diversity of geohydrologic settings is being investigated: unsaturated tuff, saturated basalt, and bedded salt. A number of approaches to assessing potential migration are being considered. Mass transfer is prominent among near-field approaches. For far-field analysis of migration in the geosphere, detailed characterizations of potential repository sites will lead to site-specific models describing radionuclide migration for a variety of postulated release scenarios. Finite-element and finite-difference codes are being used and developed to solve the mathematical equations pertinent to far-field assessments. Computational approaches presently in use generally require distribution coefficients to estimate the retardation of specific radionuclides with respect to the transport rate of water. 26 refs

  2. 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)

  3. Effects of gas overpressurisation on the geological environment of a deep repository

    International Nuclear Information System (INIS)

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

    1990-04-01

    The effect of gas generated from the deep burial of low and intermediate level radioactive wastes is being assessed. Significant volumes of gas are expected to be produced by anaerobic corrosion of metals and microbial degradation of organic materials. Work is being carried out to determine how easily the gas generated can move away from the repository, since if its flow were impeded the pressure in the repository would rise. If the flow were sufficiently impeded then the pressure rise could ultimately lead to fracturing of the vault or the flow field environment, possibly providing pathways that could accelerate the movement of radionuclides to the surface. This study considers the effects of such an overpressurisation on the integrity of the geological environment containing the repository. It attempts to quantify the pore fluid pressures at which fracturing of hard rock masses may occur by investigating a number of models of rock failure in homogeneously stressed rock and the effects of the presence of an idealised vault on the stress field. A crack opening model has also been developed which considers the effect of the overpressurisation on the dimensions of existing cracks within the rock and hence on the value of its permeability. (Author)

  4. Design information verification for spent fuel conditioning plants and for geological repositories

    International Nuclear Information System (INIS)

    Myatt, J.; Ward, M.D.

    1995-01-01

    The disposal of spent fuel is a major option for the back-end of the nuclear fuel cycle. It will require the construction, operation and eventual closure of conditioning plants and geological repositories. Consequently, a safeguards approach including Design Information Verification (DIV) must be developed for these facilities. DIV Is the examination of a completed facility to verify that it has been built to the design declared by the operator. Although DIV takes place chiefly before a plant begins routine operation, there is a continuing interest in ensuring that the plant remains as declared. That is, that the continuity of knowledge of design information is maintained during the operational phase of the plant and also post closure if necessary. A major problem with DIV of a repository is that there will be continuous structural changes during its operational life requiring advanced or special techniques for reverification. Some of these are briefly reviewed. Furthermore, since a disposal facility is expected to be operational for several decades, new mining technology may also have an impact on the DIV methods employed. Another factor in the safeguards supervision of a repository is that when the fuel has been backfilled and/or scaled in place a reassay will be a very costly exercise. The role of DIV in such novel circumstances must, therefore, be fully considered

  5. 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)

  6. Siting of the Swedish deep geological repository - experiences and plans

    International Nuclear Information System (INIS)

    Eng, T.; Backblom, G.; Thegerstrom, C.; Ahlbom, K.; Leijon, B.

    1996-01-01

    The paper provides a brief overview of the Swedish siting programme for a deep repository. A stepwise process is a key element in the planning and implementation of deep disposal of long-lived waste in Sweden. The local siting work is made in cooperation with the affected and concerned municipalities. The programs, decisions and results that so far have been reported and ongoing feasibility studies is a solid platform for the continuing siting work. It can be noted that the siting work in some cases has caused heavy opposition and negative opinions. Careful considerations on how to proceed to develop the necessary background material must therefore be made. The Environmental Impact Assessment (EIA) process that has started in conjunction with feasibility studies are judged to play an important role in the future. In this process, with extensive local involvement, critical issues can be detected at an early stage and sound ideas on both the process itself and on technical issues can be incorporated. To facilitate information exchange and cooperation between the municipalities involved and to coordinate liaison between the municipalities and county administrative boards affected by the studies, the Swedish government has appointed a National Coordinator for nuclear waste disposal. The government also has decided to provide the concerned municipalities with funding for their participation in the process. (author)

  7. 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

  8. Reliable predictions of waste performance in a geologic repository

    International Nuclear Information System (INIS)

    Pigford, T.H.; Chambre, P.L.

    1985-08-01

    Establishing reliable estimates of long-term performance of a waste repository requires emphasis upon valid theories to predict performance. Predicting rates that radionuclides are released from waste packages cannot rest upon empirical extrapolations of laboratory leach data. Reliable predictions can be based on simple bounding theoretical models, such as solubility-limited bulk-flow, if the assumed parameters are reliably known or defensibly conservative. Wherever possible, performance analysis should proceed beyond simple bounding calculations to obtain more realistic - and usually more favorable - estimates of expected performance. Desire for greater realism must be balanced against increasing uncertainties in prediction and loss of reliability. Theoretical predictions of release rate based on mass-transfer analysis are bounding and the theory can be verified. Postulated repository analogues to simulate laboratory leach experiments introduce arbitrary and fictitious repository parameters and are shown not to agree with well-established theory. 34 refs., 3 figs., 2 tabs

  9. On risk analysis for repositories in northern Switzerland: extent and probability of geological processes and events

    International Nuclear Information System (INIS)

    Buergisser, H.M.; Herrnberger, V.

    1981-01-01

    The literature study assesses, in the form of expert analysis, geological processes and events for a 1200 km 2 -area of northern Switzerland, with regard to repositories for medium- and high-active waste (depth 100 to 600 m and 600 to 2500 m, respectively) over the next 10 6 years. The area, which comprises parts of the Tabular Jura, the folded Jura and the Molasse Basin, the latter two being parts of the Alpine Orogene, has undergone a non-uniform geologic development since the Oligocene. Within the next 10 4 to 10 5 years a maximum earthquake intensity of VIII-IX (MSK-scale) has been predicted. After this period, particularly in the southern and eastern parts of the area, glaciations will probably occur, with associated erosion of possibly 200 to 300 m. Fluvial erosion as a reponse to an uplift could reach similar values after 10 5 to 10 6 years; however, there are no data on the recent relative vertical crustal movements of the area. The risk of a meteorite impact is considered small as compared to that of these factors. Seismic activity and the position and extent of faults are so poorly known within the area that the faulting probability cannot be derived at present. Flooding by the sea, intrusion of magma, diapirism, metamorphism and volcanic eruptions are not considered to be risk factors for final repositories in northern Switzerland. For the shallow-type repositories, the risk of denudation and landslides have to be judged when locality-bound projects have been proposed. (Auth.)

  10. Risk analysis for repositories in north Switzerland. Extent and probability of geologic processes and events

    Energy Technology Data Exchange (ETDEWEB)

    Buergisser, H M; Herrnberger, V

    1981-07-01

    The literature study assesses, in the form of expert analysis, geological processes and events for a 1200 km/sup 2/-area of northern Switzerland, with regard to repositories for medium- and high-active waste (depth 100 to 600 m and 600 to 2500 m, respectively) over the next 10/sup 6/ years. The area, which comprises parts of the Tabular Jura, the folded Jura and the Molasse Basin, the latter two being parts of the Alpine Orogene, has undergone a non-uniform geologic development since the Oligocene. Within the next 10/sup 4/ to 10/sup 5/ years a maximum earthquake intensity of VIII-IX (MSK-scale) has been predicted. After this period, particularly in the southern and eastern parts of the area, glaciations will probably occur, with asociated erosion of possibly 200 to 300 m. Fluvial erosion as a response to an uplift could reach similar values after 10/sup 5/ to 10/sup 6/ years; however, there are no data on the recent relative vertical crustal movements of the area. The risk of a meteorite impact is considered small as compared to that of these factors. Seismic activity and the position and extent of faults are so poorly known within the area that the faulting probability cannot be derived at present. Flooding by the sea, intrusion of magma, diapirism, metamorphism and volcanic eruptions are not considered to be risk factors for final repositories in northern Switzerland. For the shallow-type repositories, the risk of denudation and landslides have to be judged when locality-bound projects have been proposed.

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

    International Nuclear Information System (INIS)

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

    1979-11-01

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

  12. Cesium and strontium fractionation from HLW for thermal-stress reduction in a geologic repository

    International Nuclear Information System (INIS)

    McKee, R.W.

    1983-02-01

    Results are described for a study to assess the benefits and costs of fractionating the cesium and strontium components in commercial high-level waste (HLW) to a separate waste stream for the purpose of reducing geologic repository thermal stresses. System costs are developed for a broad range of conditions comparing the Cs/Sr fractionation concept with disposal of 10-year old vitrified HLW and vitrified HLW aged to achieve (through decay) the same heat output as the fractionated high-level waste (FHLW). All comparisons are based on a 50,000 metric ton equivalent (MTE) system. The FHLW and the Cs/Sr waste are both disposed of a vitrified waste but emplaced in separate areas of a basalt repository. The FHLW is emplaced in high-integrity packages at relatively high waste loading but low heat loading, while the Cs/Sr waste is emplaced in minimum integrity packages at relatively high heat loading. System cost comparisons are based on minimum cost combinations of canister diameter, waste concentration, and canister spacing in a basalt repository for each waste type. The effects on both long- and near-term safety considerations are also addressed. The major conclusion is that the Cs/Sr fractionation concept offers, potentially, a substantial total system cost advantage for HLW disposal if reduced HLW package temperatures in a basalt repository are desired. However, there is no cost advantage if currently designated maximum design temperatures are acceptable. Aging the HLW for 50 to 100 years can accomplish similar results at equivalent or loser costs

  13. Design information verification (DIV) of closed geological repositories (SAGOR activity 3c)

    International Nuclear Information System (INIS)

    Myatt, J.

    1998-02-01

    Following IAEA Advisory and Consultants Group meetings in September 1988 and in May 1991 respectively an IAEA multi-national Support Programme Task was initiated to consider the 'Development of Safeguards for Final Disposal of Spent Fuel in Geological Repositories' (SAGOR). A 'Technical Coordination Committee' (TCC) was set up with invited representatives from those Member State Support Programmes wishing to be involved. The joint programme, through the TCC, was given the task of studying the safeguards requirements in: conditioning plant (where the spent fuel is prepared for transfer to the repository); operating repositories (i.e. those in which the fuel is being emplaced); closed repositories. At the first meeting of the TCC in Washington in July 1994 the UK undertook to provide a study of the Design Information Verification (DIV) required in all three areas. For this activity the requirements, techniques and procedures for the Design Information Verification (DIV) of closed repositories have been considered. In completing the study the findings reported for activities 1b/c and 2c (descriptions of a Model Repository and Potential Diversion Paths, respectively) have been used in formulating any conclusions reached. It is also debatable as to whether this activity is strictly speaking DIV or is one of surveillance. As undeclared access can only be made to the emplacement areas of the repository by altering the physical makeup of the surrounding area; i.e. physically changing the 'design' of the surrounding area, however, this is deemed to be DIV. Although the techniques used appear to be those of surveillance they are being applied in this case as the tools of DIV. As with any facility there are a number of stages in its lifetime. For the purposes of this report the operating life of a repository is defined as being the time from inception to when it is finally decommissioned and sealed with the ground surface returned to being a green field. The repository is

  14. Finite element code FENIA verification and application for 3D modelling of thermal state of radioactive waste deep geological repository

    Science.gov (United States)

    Butov, R. A.; Drobyshevsky, N. I.; Moiseenko, E. V.; Tokarev, U. N.

    2017-11-01

    The verification of the FENIA finite element code on some problems and an example of its application are presented in the paper. The code is being developing for 3D modelling of thermal, mechanical and hydrodynamical (THM) problems related to the functioning of deep geological repositories. Verification of the code for two analytical problems has been performed. The first one is point heat source with exponential heat decrease, the second one - linear heat source with similar behavior. Analytical solutions have been obtained by the authors. The problems have been chosen because they reflect the processes influencing the thermal state of deep geological repository of radioactive waste. Verification was performed for several meshes with different resolution. Good convergence between analytical and numerical solutions was achieved. The application of the FENIA code is illustrated by 3D modelling of thermal state of a prototypic deep geological repository of radioactive waste. The repository is designed for disposal of radioactive waste in a rock at depth of several hundred meters with no intention of later retrieval. Vitrified radioactive waste is placed in the containers, which are placed in vertical boreholes. The residual decay heat of radioactive waste leads to containers, engineered safety barriers and host rock heating. Maximum temperatures and corresponding times of their establishment have been determined.

  15. Staff Technical Position on consideration of fault displacement hazards in geologic repository design

    International Nuclear Information System (INIS)

    McConnell, K.I.; Lee, M.P.

    1994-09-01

    Nuclear Regulatory Commission regulations for the disposal of spent nuclear fuel and high-level radioactive waste in a geologic repository recognize that fault displacement is a potentially adverse condition. However, they do not prohibit designing the geologic repository against the effects of such a potentially adverse condition. This Staff Technical Position recognizes the acceptability of designing the geologic repository to take into account the attendant effects (e.g., displacement) of faults of regulatory concern and expresses the staff's views on what is needed from the US Department of Energy if it chooses to locate structures, systems, and components important to safety or important to waste isolation in areas that contain faults of regulatory concern

  16. Tectonic risk forecasting through expert elicitation for geological repositories: the TOPAZ project

    Energy Technology Data Exchange (ETDEWEB)

    Goto, Junichi [NUMO, Tokyo (Japan); Kawamura, Hideki [Obayashi Corporation, Tokyo (Japan); Chapman, Neil [MCM Consulting, Baden (Switzerland)

    2013-07-01

    This paper describes the development of a probabilistic methodology for the evaluation of tectonic hazards to geological repositories in Japan. The approach is a development of NUMO's ITM methodology, which produced probabilistic hazard maps for volcanism and rock deformation for periods up to about 100,000 years in a set of Case Studies that covered a large area of the country. To address potential regulatory requirements, the TOPAZ project has extended the ITM methodology to look into the period between 100,000 and 1 million years, where significant uncertainties begin to emerge about the tectonic framework within which quantitative forecasting can be made. Part of this methodology extension has been to adopt expert elicitation techniques to capture differing expert views as a means of addressing such uncertainties. This paper briefly outlines progress in this development work to date. (authors)

  17. Proposal for the classification of scenarios for deep geological repositories in probability classes

    International Nuclear Information System (INIS)

    Beuth, Thomas

    2013-03-01

    The provided report was elaborated in the framework of the project 3609R03210 ''Research and Development for Proof of the long-term Safety of Deep Geological Repositories''. It contains a proposal for a methodology that enables the assignment of developed scenarios in the frame of Safety Cases to defined probability classes. The assignment takes place indirectly through the categorization of the defining relevant factors (so-called FEP: Features, Events and Processes) of the respective scenarios also in probability classes. Therefore, decision trees and criteria were developed for the categorization of relevant factors in classes. Besides the description of the methodology another focal point of the work was the application of the method taking into account a defined scenario. By means of the scenario the different steps of the method and the decision criteria were documented, respectively. In addition, potential subjective influences along the path of decisions regarding the assignment of scenarios in probability classes were identified.

  18. Tectonic risk forecasting through expert elicitation for geological repositories: the TOPAZ project

    International Nuclear Information System (INIS)

    Goto, Junichi; Kawamura, Hideki; Chapman, Neil

    2013-01-01

    This paper describes the development of a probabilistic methodology for the evaluation of tectonic hazards to geological repositories in Japan. The approach is a development of NUMO's ITM methodology, which produced probabilistic hazard maps for volcanism and rock deformation for periods up to about 100,000 years in a set of Case Studies that covered a large area of the country. To address potential regulatory requirements, the TOPAZ project has extended the ITM methodology to look into the period between 100,000 and 1 million years, where significant uncertainties begin to emerge about the tectonic framework within which quantitative forecasting can be made. Part of this methodology extension has been to adopt expert elicitation techniques to capture differing expert views as a means of addressing such uncertainties. This paper briefly outlines progress in this development work to date. (authors)

  19. Radioactive waste disposal programme and siting regions for geological deep repositories. Executive summary. November 2008

    International Nuclear Information System (INIS)

    2008-11-01

    There are radioactive wastes in Switzerland. Since many decades they are produced by the operation of the five nuclear power plants, by medicine, industry and research. Important steps towards the disposal of these wastes are already realized; the corresponding activities are practised. This particularly concerns handling and packaging of the radioactive wastes, their characterization and inventory, as well as the interim storage and the inferred transportations. Preparatory works in the field of scientific research on deep geological repositories have allowed to acquire high level of technical and scientific expertise in that domain. The feasibility of building long-term safe geological repositories in Switzerland was demonstrated for all types of radioactive wastes; the demonstration was accepted by the Federal Council. There is enough knowledge to propose geological siting regions for further works. The financial funds already accumulated guaranty the financing of the dismantling of the power plants as well as building deep geological repositories for the radioactive wastes. The regulations already exist and the organisational arrangements necessary for the fruitful continuation of the works already done have been taken. The programme of the disposal of radioactive wastes also describes the next stages towards the timely realization of the deep repositories as well as the level of the financial needs. The programme is updated every five years, checked by the regulatory bodies and accepted by the Federal Council who reports to the parliament. The process of choosing a site, which will be completed in the next years, is detailed in the conceptual part of the programme for deep geological repositories. The NAGRA proposals are based exclusively on technical and scientific considerations; the global evaluation taking into account also political considerations has to be performed by the authorities and the Federal Council. The programme states that at the beginning of

  20. A geologic scenario for catastrophic failure of the Yucca Mountain Nuclear Waste Repository, Nevada

    International Nuclear Information System (INIS)

    McMackin, M.R.

    1993-01-01

    A plausible combination of geologic factors leading to failure can be hypothesized for the Yucca Mountain Nuclear Waste Repository. The scenarios is constructed using elementary fault mechanics combined with geologic observations of exhumed faults and published information describing the repository site. The proposed repository site is located in the Basin and Range Province, a region of active crustal deformation demonstrated by widespread seismicity. The Yucca Mountain area has been characterized as tectonically quiet, which in the context of active crustal deformation may indicate the accumulation of the stresses approaching the levels required for fault slip, essentially stick-slip faulting. Simultaneously, dissolution of carbonate rocks in underlying karst aquifers is lowering the bulk strength of the rock that supports the repository site. Rising levels of hydrostatic stress concurrent with a climatically-driven rise in the water table could trigger faulting by decreasing the effective normal stress that currently retards fault slip. Water expelled from collapsing caverns in the underlying carbonate aquifer could migrate upward with sufficient pressure to open existing fractures or create new fractures by hydrofracturing. Water migrating through fractures could reach the repository in sufficient volume to react with heated rock and waste perhaps creating steam explosions that would further enhance fracture permeability. Closure of conduits in the underlying carbonate aquifer could lead to the elevation of the saturated zone above the level of the repository resulting in sustained saturation of radioactive waste in the repository and contamination of through-flowing groundwater

  1. Problems of geologic survey of high level radioactive waste repositories illustrated on the testing site in the Melechov Massif

    International Nuclear Information System (INIS)

    Mlcoch, B.

    1997-01-01

    Major attention is paid to problems associated with the geologic maps of the prospective repository site, which lies within the Bohemian Massif. Structural geology, survey through boreholes, and primary database are also discussed briefly. (P.A.)

  2. Siting regions for deep geological repositories. Nagra’s proposals for stage 3

    International Nuclear Information System (INIS)

    2014-01-01

    This brochure published by the Swiss National Cooperative for the Disposal of Radioactive Waste (NAGRA) discusses the selection of sites for deep geological repositories for nuclear wastes in Switzerland. The procedure proposed for the selection process is explained. The four sites for possible repositories of high-level radioactive waste as well as for low and intermediate-level wastes are described and rated with respect to the various safety factors involved. The reasons for the long-term safety measures proposed and the geological barriers involved are discussed. The four proposals for depository sites are looked at in more detail. The paper is well illustrated with several diagrams and tables

  3. The general situation of clay site for high-level waste geological disposal repository

    International Nuclear Information System (INIS)

    Wang Changxuan; Liu Xiaodong; Liu Pinghui

    2008-01-01

    Host medium is vitally important for safety of high-level radiaoactive waste (HLW) geological disposal. Clay, as host media of geological repository of HLW, has received greater attention for its inherent advantages. This paper summarizes IAEA and OECD/NEA's some safety guides on site selection and briefly introduces the process of the site selection, their studies and the characteristics of the clay formations in Switz-erland, France and Belgian. Based on these analyses, some suggestions are made to China's HLW repository clay site selection. (authors)

  4. Copper corrosion under expected conditions in a deep geologic repository

    Energy Technology Data Exchange (ETDEWEB)

    King, F. [Integrity Corrosion Consulting Ltd, Calgary, Alberta (Canada); Ahonen, L. [Geological Survey of Finland, Espoo (Finland); Taxen, C. [Swedish Corrosion Inst., Stockholm (Sweden); Vuorinen, U. [VTT Chemical Technology, Espoo (Finland); Werme, L. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    2001-12-01

    Copper has been the corrosion barrier of choice for the canister in the Swedish and Finnish, nuclear waste disposal programmes for over 20 years. During that time many studies have been carried out on the corrosion behaviour of copper under conditions likely to exist in an underground nuclear disposal repository located in he Fenno-Scandian bedrock. This review is a summary of what has been learnt about the long- term behaviour of the corrosion barrier during this period and what the implications of this knowledge are for the predicted service life of the canisters. The review is based on the existing knowledge from various nuclear waste management programs around the world and from the open literature.Various areas are considered: the expected evolution of the geochemical conditions in the groundwater and of the repository environment, the thermodynamics of copper corrosion, corrosion before and during saturation of the compacted bentonite buffer by groundwater, general and localized corrosion following saturation of the compacted bentonite buffer, stress corrosion cracking, radiation effects, the implications of corrosion on the service life of the canister, and areas for further study. Much has been learnt about the long-term corrosion behaviour of copper canisters over the past 20 years. The majority of the information reviewed here is drawn from the Swedish/Finnish and Canadian programmes. Despite differences in scientific approach, and canister and repository design, the results of these two programmes both suggest that copper provides an excellent corrosion barrier in an underground repository. The conclusion drawn from this review is that the original prediction made in 1978 of canister lifetimes exceeding 100,000 years remains valid.

  5. Copper corrosion under expected conditions in a deep geologic repository

    Energy Technology Data Exchange (ETDEWEB)

    King, F.; Ahonen, L.; Taxen, C.; Vuorinen, U.; Werme, L

    2002-01-01

    Copper has been the corrosion barrier of choice for the canister in the Swedish and Finnish, nuclear waste disposal programmes for over 20 years. During that time many studies have been carried out on the corrosion behaviour of copper under conditions likely to exist in an underground nuclear disposal repository located in the Fenno-Scandian bedrock. This review is a summary of what has been learnt about the long-term behaviour of the corrosion barrier during this period and what the implications of this knowledge are for the predicted service life of the canisters. The review is based on the existing knowledge from various nuclear waste management programs around the world and from the open literature. Various areas are considered: the expected evolution of the geochemical conditions in the groundwater and of the repository environment, the thermodynamics of copper corrosion, corrosion before and during saturation of the compacted bentonite buffer by groundwater, general and localized corrosion following saturation of the compacted bentonite buffer, stress corrosion cracking, radiation effects, the implications of corrosion on the service life of the canister, and areas for further study. Much has been learnt about the long-term corrosion behaviour of copper canisters over the past 20 years. The majority of the information reviewed here is drawn from the Swedish/Finnish and Canadian programmes. Despite differences in scientific approach, and canister and repository design, the results of these two programmes both suggest that copper provides an excellent corrosion barrier in an underground repository. The conclusion drawn from this review is that the original prediction made in 1978 of canister lifetimes exceeding 100,000 years remains valid. (orig.)

  6. Copper corrosion under expected conditions in a deep geologic repository

    International Nuclear Information System (INIS)

    King, F.; Ahonen, L.; Taxen, C.; Vuorinen, U.; Werme, L.

    2001-12-01

    Copper has been the corrosion barrier of choice for the canister in the Swedish and Finnish, nuclear waste disposal programmes for over 20 years. During that time many studies have been carried out on the corrosion behaviour of copper under conditions likely to exist in an underground nuclear disposal repository located in he Fenno-Scandian bedrock. This review is a summary of what has been learnt about the long- term behaviour of the corrosion barrier during this period and what the implications of this knowledge are for the predicted service life of the canisters. The review is based on the existing knowledge from various nuclear waste management programs around the world and from the open literature.Various areas are considered: the expected evolution of the geochemical conditions in the groundwater and of the repository environment, the thermodynamics of copper corrosion, corrosion before and during saturation of the compacted bentonite buffer by groundwater, general and localized corrosion following saturation of the compacted bentonite buffer, stress corrosion cracking, radiation effects, the implications of corrosion on the service life of the canister, and areas for further study. Much has been learnt about the long-term corrosion behaviour of copper canisters over the past 20 years. The majority of the information reviewed here is drawn from the Swedish/Finnish and Canadian programmes. Despite differences in scientific approach, and canister and repository design, the results of these two programmes both suggest that copper provides an excellent corrosion barrier in an underground repository. The conclusion drawn from this review is that the original prediction made in 1978 of canister lifetimes exceeding 100,000 years remains valid

  7. Sequential evaluation of the potential geologic repository site at Yucca Mountain, Nevada, USA

    International Nuclear Information System (INIS)

    Bjerstedt, T.W.

    1996-01-01

    This paper discusses the changes that are planned for the characterization program at Yucca Mountain due to budget changes. Yucca Mountain is the only site being studied in the US for a geologic repository. Funding for the site characterization program at Yucca Mountain program was cut by roughly one half from the 1994 projected budget to complete three major milestones. These project milestones included: (1) a time-phased determination of site suitability, and if a positive finding, (2) completion of an Environmental Impact Statement, and (3) preparation of a License Application to the US NRC to authorize repository construction. In reaction, Yucca Mountain Site Characterization Project has shifted from parallel development of these milestones to a sequenced approach with the site suitability evaluation being replaced with a management assessment. Changes to the regulatory structure for the disposal program are under consideration by DOE and the NRC. The possibility for NRC and Doe to develop a site-specific regulatory structure follows from the National Energy Policy Act of 1992 that authorized the US EPA to develop a site specific environmental standard for Yucca Mountain

  8. Siting regions for deep geological repositories. Why just here?; Standortgebiete fuer geologische Tiefenlager. Warum gerade hier?

    Energy Technology Data Exchange (ETDEWEB)

    Rieser, A

    2009-09-15

    This report helps to the popularization of the Nagra works accomplished for the management and disposal of the radioactive wastes in Switzerland. The programme for management and disposal of the radioactive wastes are extensively determined by regulations. Protection of mankind and environment is the primary objective. The basic storage process is considered as having been solved. The question addressed in the report is where the facility has to be built; the site selection procedure includes five steps: 1) according to their type the wastes have to be allocated to two different repositories: for low- and intermediate-level wastes (L/ILW), and for high-level and alpha-toxic wastes (HLW); 2) the safety concept for both repositories and the requirements on the geology have to be determined; 3) large suitable geological-tectonic zones must be found where repositories could be built; 4) in these geological zones a suitable host rock has to be identified; 5) the most important spatial geological conditions of the host rock (minimum depth with respect to surface erosion, maximum depth in terms of engineering requirements, lateral extent) have to be identified. Based on these criteria, three suitable siting regions for a HLW repository were found in the North of Switzerland. The preferred host rock is Opalinus clay because of its very low permeability; it is therefore an excellent barrier against nuclide transport. In the three proposed siting regions, Opalinus clay is present in sufficient volumes at a suitable depth. For a L/ILW repository six different possible siting regions were identified, five in Northern Switzerland and one in Central Switzerland. In the three siting regions found for a possible HLW repository, it would also be possible to built a combined repository for both HLW and L/ILW wastes.

  9. Geological boundary conditions for a safety demonstration and verification concept for a HLW repository in claystone in Germany. AnSichT

    Energy Technology Data Exchange (ETDEWEB)

    Stark, Lena; Bebiolka, Anke; Gerardi, Johannes [Federal Institute for Geosciences and Natural Resources (BGR), Hannover (Germany). Dept. of Underground Space for Storage and Economic Use; and others

    2015-07-01

    Within the framework of the R and D project ''AnSichT'', DBE TECHNOLOGY, BGR and GRS are developing a method to demonstrate the safety of a HLW repository in claystone in Germany. The methodological approach basing on a holistic concept, links the legal and geologic boundary conditions, the disposal and closure concept, the demonstration of barrier integrity, and the long-term analysis of the repository evolution as well. The geologic boundary conditions are specified by the description of the geological situation and generic models, the selection of representative parameters and geoscientific long-term predictions. They form a fundament for the system analysis.

  10. Analysis on the use of engineered barriers for geologic isolation of spent fuel in a reference salt site repository

    International Nuclear Information System (INIS)

    Cloninger, M.O.; Cole, C.R.; Washburn, J.F.

    1980-12-01

    A perspective on the potential durability and effectiveness requirements for the waste form, container and other engineered barriers for geologic disposal of spent nuclear fuel has been developed. This perspective is based on calculated potential doses to individuals who may be exposed to radioactivity released from a repository via a groundwater transport pathway. These potential dose commitments were calculated with an integrated geosphere transport and bioshpere transport model. A sensitivity analysis was accomplished by varying four important system parameters, namely the waste radionuclide release rate from the repository, the delay prior to groundwater contact with the waste (leach initiation), aquifer flow velocity and flow path length. The nuclide retarding capacity of the geologic media, a major determinant of the isolation effectiveness, was not varied as a parameter but was held constant for a particular reference site. This analysis is limited to looking only at engineered barriers whose net effect is either to delay groundwater contact with the waste form or to limit the rate of release of radionuclides into the groundwater once contact has occurred. The analysis considers only leach incident scenarios, including a water well intrusion into the groundwater near a repository, but does not consider other human intrusion events or catastrophic events. The analysis has so far been applied to a reference salt site repository system and conclusions are presented.Basically, in nearly all cases, the regional geology is the most effective barrier to release of radionuclides to the biosphere; however, for long-lived isotopes of carbon, technetium and iodine, which were poorly sorbed on the geologic media, the geology is not very effective once a leach incident is initiated

  11. Modeling of container failure and radionuclide release from a geologic nuclear waste repository

    International Nuclear Information System (INIS)

    Kim, Chang Lak; Kim, Jhin Wung; Choi, Kwang Sub; Cho, Chan Hee

    1989-02-01

    Generally, two processes are involved in leaching and dissolution; (1) chemical reactions and (2) mass transfer by diffusion. The chemical reaction controls the dissolution rates only during the early stage of exposure to groundwater. The exterior-field mass transfer may control the long-term dissolution rates from the waste solid in a geologic repository. Masstransfer analyses rely on detailed and careful application of the governing equations that describe the mechanistic processes of transport of material between and within phases. We develop analytical models to predict the radionuclide release rate into the groundwater with five different approaches: a measurement-based model, a diffusion model, a kinetics model, a diffusion-and-kinetics model, and a modified diffusion model. We also collected experimental leaching data for a partial validation of the radionuclide release model based on the mass transfer theory. Among various types of corrosions, pitting is the most significant because of its rapid growth. The failure time of the waste container, which also can be interpreted as the containment time, is a milestone of the performance of a repository. We develop analytical models to predict the pit growth rate on the container surface with three different approaches: an experimental method, a statistical method, and a mathematical method based on the diffusion theory. (Author)

  12. 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)

  13. 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)

  14. Sources/treatment of uncertainties in the performance assessment of geologic radioactive waste repositories

    International Nuclear Information System (INIS)

    Cranwell, R.M.

    1987-01-01

    Uncertainties in the performance assessment of geologic radioactive waste repositories have several sources. The more important ones include: 1) uncertainty in the conditions of a disposal system over the temporal scales set forth in regulations, 2) uncertainty in the conceptualization of the geohydrologic system, 3) uncertainty in the theoretical description of a given conceptual model of the system, 4) uncertainty in the development of computer codes to implement the solution of a mathematical model, and 5) uncertainty in the parameters and data required in the models and codes used to assess the long-term performance of the disposal system. This paper discusses each of these uncertainties and outlines methods for addressing these uncertainties

  15. The velocity dependent dissolution of spent nuclear fuel in a geologic repository

    International Nuclear Information System (INIS)

    Nutt, W.M.

    1990-02-01

    A model describing the dissolution of fission products and transuranic isotopes from spent nuclear fuel into flowing ground water has been developed. This model is divided into two parts. The first part of the model calculates the temperature within a consolidated spent fuel waste form at a given time and ground water velocity. This model was used to investigate whether water flowing at rates representative of a geological repository located at Yucca Mountain, Nevada, will cool a wasteform consisting of consolidated spent nuclear fuel pins. Time and velocity dependent temperature profiles were generated. These profiles were input into the second model, which calculates the dissolution rate of waste isotopes from a spent fuel pin. Two dissolution limiting processes were modeled; the processes are dissolution limited by the solubility limit of an isotopes in the ground water, and dissolution limited by the diffusion of waste isotopes from the interior of a spent fuel pin to the surface where dissolution can occur

  16. 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

  17. 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

  18. Evaluation of behaviour and Safety in a geologic deep repository

    International Nuclear Information System (INIS)

    1997-01-01

    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. This Safety Assessment constitutes a first step within a systematical process that will permit, thorough successive approximations, to predict the performance of the different barriers of the disposal system, and its capability to comply with the assigned safety functions and with the established safety criteria. The primary bases for this Safety Assessment are the following: The disposal concept considers the storage of the fuel assemblies in carbon steel canisters of 10 cm of thickness, emplaced horizontally in galleries excavated in granite of 2,4 m of diameter and 500 m of length, using a bentonite thickness of 75 cm around canisters as buffer material. The repository is located in a granitic site defined with available data about surface characteristics of Spanish granites. The exercise uses a probabilistic approximation in order to cope with the uncertainties associated with the different imputs parameters. (Author)

  19. Swiss plans for deep geological repositories for radioactive wastes - Basics for communication at the localities affected

    International Nuclear Information System (INIS)

    Gallego Carrera, D.; Renn, O.; Dreyer, M.

    2009-06-01

    This report for the Swiss Federal Office of Energy (SFOE) discusses the concept of how information concerning deep geological repositories for radioactive wastes should be presented and communicated to those in the areas which have been designated as potential sites for the repositories. Communication basics based on scientific knowledge in this area are discussed. The importance of a concept for general communication and risk-communication as a particular challenge are discussed. Trust and transparency are quoted as being indispensable in this connection. Ways of dealing with various target audiences and the media are examined. The report is concluded with a check-list that deals with important questions arising from the process of communicating information on deep geological repositories for radioactive wastes

  20. Site selection of a deep repository of HLRW in relation to geological conditions of Slovak Republic

    International Nuclear Information System (INIS)

    Kovacik, M.; Kovacikova, M.; Madaras, J.; Vandlikova, M.

    1996-01-01

    All countries which use nuclear energy to generate electricity face the problem of high level radioactive waste (HLRW) and spent fuel. Until 1987, this problem was addressed in Czechoslovakia by transferring the material to the former USSR. After the political changes in Central and Eastern Europe in 1989 and the division of Czechoslovakia into two states in 1993, Slovakia independently faced the complex problem of creating its own deep repository. Although Slovakia has begun to solve the problem of HLRW and spent fuel only recently, it can take advantage of the theoretical and practical knowledge of other countries in this field. The geological aspects of the setting of the deep repository of HLRW have been studied within the project R epositories of radioactive and hazardous wastes in geological environment. The assessment of the Slovak Republic for creating a repository of HLRW was based on the application of internationally determined and applied criteria

  1. Important processes affecting the release and migration of radionuclides from a deep geological repository

    International Nuclear Information System (INIS)

    Barátová, Dana; Nečas, Vladimír

    2017-01-01

    The processes that affect significantly the transport of contaminants through the near field and far field of a deep geological repository of spent nuclear fuel were studied. The processes can be generally divided into (i) processes related to the release of radionuclides from the spent nuclear fuel; (ii) processes related to the radionuclide transport mechanisms (such as advection and diffusion); and (iii) processes affecting the rate of radionuclide migration through the multi-barrier repository system. A near-field and geosphere model of an unspecified geological repository sited in a crystalline rock is also described. Focus of the treatment is on the effects of the different processes on the activity flow of the major safety-relevant radionuclides. The activity flow was simulated for one spent fuel cask by using the GoldSim simulation tool. (orig.)

  2. The application of nuclear geophysics method to evaluate the geological environment of nuclear waste repository

    International Nuclear Information System (INIS)

    Fang, Fang; Xiaoqin, Wang; Kuanliang, Li; Xinsheng, Hou; Jingliang, Zhu; Binxin, Hu

    2002-01-01

    'Cleanly land should be given back ground.' This is a task while nuclear engineering have to be retired. We applied the nuclear geophysics methods and combined with geology, hydrology, geochemistry, and other methods, to evaluate the environment of nuclear waste repository. It is the important work to renovate environment and prepare technology before ex-service of the nuclear engineering

  3. Albedo Neutron Dosimetry in a Deep Geological Disposal Repository for High-Level Nuclear Waste.

    Science.gov (United States)

    Pang, Bo; Becker, Frank

    2017-04-28

    Albedo neutron dosemeter is the German official personal neutron dosemeter in mixed radiation fields where neutrons contribute to personal dose. In deep geological repositories for high-level nuclear waste, where neutrons can dominate the radiation field, it is of interest to investigate the performance of albedo neutron dosemeter in such facilities. In this study, the deep geological repository is represented by a shielding cask loaded with spent nuclear fuel placed inside a rock salt emplacement drift. Due to the backscattering of neutrons in the drift, issues concerning calibration of the dosemeter arise. Field-specific calibration of the albedo neutron dosemeter was hence performed with Monte Carlo simulations. In order to assess the applicability of the albedo neutron dosemeter in a deep geological repository over a long time scale, spent nuclear fuel with different ages of 50, 100 and 500 years were investigated. It was found out, that the neutron radiation field in a deep geological repository can be assigned to the application area 'N1' of the albedo neutron dosemeter, which is typical in reactors and accelerators with heavy shielding. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. 10 CFR 63.113 - Performance objectives for the geologic repository after permanent closure.

    Science.gov (United States)

    2010-01-01

    ... closure. (a) The geologic repository must include multiple barriers, consisting of both natural barriers... in combination with natural barriers, radiological exposures to the reasonably maximally exposed... engineered barrier system must be designed so that, working in combination with natural barriers, releases of...

  5. An overview on the national strategy to implement a deep geological repository in Romania

    International Nuclear Information System (INIS)

    Negut, G.; Ghitescu, P.; Dupleac, D.; Prisecaru, I.

    2010-01-01

    Since 1996 in Romania was started operation Candu 700 MW Unit 1 Cernavoda Nuclear Power Station and in 2007 begun operation of the Candu 700 MW Unit 2. The energy produced by nuclear units is accompanied by radioactive waste production. According with European Union requirements in Romania was created National Agency for Radioactive Waste (ANDRAD) in 2003. ANDRAD business is radioactive waste management. ANDRAD, together with the stakeholders, worked the law of great radioactive waste generators contribution for radioactive waste management, which was approved by Governmental Ordinance in September 2007. ANDRAD is responsible manager of this fund. ANDRAD is responsible, also, with the National Strategy for radioactive waste management. Romania's National Strategy for Energy approved in 2007 by Government Ordinance says that a deep geological repository for spent fuel (SF) and High Level Waste (HLW) is to be put in operation around 2055. IAEA supported ANDRAD in a Technical Cooperation Project for a concept of a geological repository of radioactive waste. A strategy to implement o geological repository in Romania was drafted. There are problems with potential rocks and sites to host a geological repository. There are problems for funding this project and also sensitive and serious problems connected with social and political issues. Paper presents this strategy and all the problems arisen by implantation of this strategy. (authors)

  6. 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

  7. New simulation tools for long-term hydraulic design for a geological repository

    International Nuclear Information System (INIS)

    Richard, S.; Chaudon, L.

    1995-01-01

    Hydraulic concepts for a geological repository were investigated. Numerical simulations were adapted for this purpose and an experimental rheoelectric method based on an analogy between hydraulic flows and electric currents was developed. The results are discussed in this paper. A simplified representation of the host rock was adopted to account for the geometric details of the concept; this rock was described by a homogeneous porous medium associated with two major discontinuities. Steady-state hydraulic conditions were considered, and heating by the waste packages was assumed to be negligible (these conditions correspond to the long-term repository setting). The hydraulic structures obtained by the two methods are comparable, but significant differences were observed in the drained water distribution in the excavations; these discrepancies highlight the importance of the calculation mesh dimensions. Drainage barriers (drainage drifts and boreholes) surrounding the disposal boreholes may reduce water circulation in the disposal areas to their initial levels by constituting a partial hydraulic Faraday cage. This could be achieved with a reasonable number of boreholes if necessary

  8. The technical and economical optimization of the French geological repository project - 59275

    International Nuclear Information System (INIS)

    Raffard, Rodolphe; Labalette, Thibaud

    2012-01-01

    Document available in abstract form only. Full text of publication follows: The French Act of 28 June 2006 made the choice of reversible geological repository for long term management of high level and long-lived intermediate level waste. Andra is in charge of designing, building and operating the future industrial repository Cigeo. Current major issues consist in preparing the application to be examined in 2015, planning the construction so that operation would start in 2025 and optimizing the design on both technical and economical points of view. The Dossier 2005 -provided by Andra prior to the 2006 Act- established the feasibility of the project, especially towards compliance with safety and reversibility. Design options were presented at that time with the objective of demonstrating feasibility without ruling out possibilities of further optimization. Along with the scientific and technical review of Dossier 2005, a number of design optimization topics were identified in 2006. Working groups involved Andra's specialists as well as external experts. A particular attention was given to (i) the industrial experience of waste producers and (ii) the characteristics of the clay layer investigated in the Meuse/Haute-Marne Underground Research Laboratory. The 2006 optimization topics were prioritized taking into account their economical impact and the development plan of the project

  9. 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.

  10. 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

  11. 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

  12. Release consequence analysis for a hypothetical geologic radioactive waste repository in salt

    International Nuclear Information System (INIS)

    1979-08-01

    One subtask conducted under the INFCE program is to evaluate and compare the health and safety impacts of different fuel cycles in which all radioactive wastes (except those from mining and milling) are placed in a geologic repository in salt. To achieve this objective, INFCE Working Group 7 examined the radiologic dose to humans from geologic repositories containing waste arisings as defined for seven reference fuel cycles. This report examines the release consequences for a generic waste repository in bedded salt. The top of the salt formation and the top of the repository are assumed to be 250 and 600 m, respectively, below the surface. The hydrogeologic structure above the salt consists of two aquifers and two aquitards. The aquifers connect to a river 6.2 km from the repository. The regional gradient to the river is 1 m/km in all aquifers. Hydrologic, transport, and dose models were used to model two release scenarios for each fuel cycle, one without a major disturbance and one in which a major geologic perturbation breached the repository immediately after it was sealed. The purpose of the modeling was to predict the rate of transport of radioactive contaminants from the repository through the geosphere to the biosphere, and to determine the potential dose to humans. Of the many radionuclides in the waste, only 129 I and 226 Ra arrived at the river in sufficient concentrations for a measurable dose calculation. Radionuclide concentrations in the ground water pose no threat to man because the ground water is a concentrated brine and it is diluted by a factor of 10 6 to 10 7 upon entering the river

  13. Impact on geologic repository usage from limited actinide recycle in pressurized light water reactors

    International Nuclear Information System (INIS)

    Wigeland, Roald A.; Bauer, Theodore H.; Hill, Robert N.; Stillman, John A.

    2007-01-01

    A project has been conducted as part of the U.S. Department of Energy Advanced Fuel Cycle Initiative to evaluate the impact of limited actinide recycling in light water reactors on the utilization of a geologic repository where loading of the repository is constrained by the decay heat of the emplaced materials. In this study, it was assumed that spent PWR fuel was processed, removing the uranium, plutonium, americium, and neptunium, along with the fission products cesium and strontium. Previous work had demonstrated that these elements were responsible for limiting loading in the repository based on thermal constraints. The plutonium, americium, and neptunium were recycled in a PWR, with process waste and spent recycled fuel being sent to the repository. The cesium and strontium were placed in separate storage for 100-300 years to allow for decay prior to disposal. The study examined the effect of single and multiple recycles of the recovered plutonium, americium, and neptunium, as well as different processing delay times. The potential benefit to the repository was measured by the increase in utilization of repository space as indicated by the allowable linear loading in the repository drifts (tunnels). The results showed that limited recycling would provide only a small fraction of the benefit that could be achieved with repeated processing and recycling, as is possible in fast neutron reactors. (author)

  14. 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

  15. Geological investigations for the South African nuclear waste repository facility

    International Nuclear Information System (INIS)

    Hambleton-Jones, B.B.; Levin, M.; Andersen, N.J.B.; Brynard, H.J.; Toens, P.D.

    1984-02-01

    The selection of the Vaalputs site on the arid Bushmanland Plateau in the northwestern Cape of the Republic of South Africa for the disposal of low-level radioactive waste was based on a national screening phase program involving socio-economic and geological criteria. Regional geohydrological studies over an area of 27,000 km 2 and a detailed study over 1,300 km 2 indicated that in general the groundwater is saline and that Vaalputs and environs was the most favourable area. The groundwater table lies between 30 and 45 m below the surface, with 14 C ages between 2,500 and 9,000 years old in the immediate vicinity. The geology of Vaalputs consists of Proterozoic granites, gneisses, metasediments, and noritoids of the 1,050 Ma Namaqualand Metamorphic Complex. Upper cretaceous kimberlitic and basaltic intrusions occur locally. Overlying these basement rocks surficial upper Tertiary to Recent argillaceous sediments occur in the Vaalputs basin. The sediments consist of aeolian sand, calcrete, fluvial sandy to gritty clay, white kaolinised clay and very weathered basement rocks. It is in these rocks that the low-level waste trenches will be located. Extensive airborne geophysical surveys, such as aeromagnetics, INPUT, and infrared thermal line scanning, were undertaken to assist in the evaluation of the regional and local subsurface geology. Ground geophysical surveys included refraction seismics, electromagnetics, magnetics, borehole radiometrics and resistivity. Geohydrological modelling of the unsaturated and saturated zones is in progress

  16. Siting, design and construction of a deep geological repository for the disposal of high level and alpha bearing wastes

    International Nuclear Information System (INIS)

    1990-06-01

    The main objective of this document is to summarize the basic principles and approaches to siting, design and construction of a deep geological repository for disposal of high level and alpha bearing radioactive wastes, as commonly agreed upon by Member States. This report is addressed to decision makers and technical managers as well as to specialists planning for siting, design and construction of geological repositories for disposal of high level and alpha bearing wastes. This document is intended to provide Member States of the IAEA with a summary outline for the responsible implementing organizations to use for siting, designing and constructing confinement systems for high level and alpha bearing radioactive waste in accordance with the protection objectives set by national regulating authorities or derived from safety fundamentals and standards of the IAEA. The protection objectives will be achieved by the isolation of the radionuclides from the environment by a repository system, which consists of a series of man made and natural safety barriers. Engineered barriers are used to enhance natural geological containment in a variety of ways. They must complement the natural barriers to provide adequate safety and necessary redundancy to the barrier system to ensure that safety standards are met. Because of the long timescales involved and the important role of the natural barrier formed by the host rock, the site selection process is a key activity in the repository design and development programme. The choice of the site, the investigation of its geological setting, the exploration of the regional hydrogeological setting and the primary underground excavations are all considered to be part of the siting process. 16 refs

  17. Development of site suitability criteria for the high level waste repository for Lawrence Livermore Laboratories

    International Nuclear Information System (INIS)

    1977-06-01

    Results of our mining, geological and geotechnical studies provided in support of the development of site suitability criteria for the high level waste repository are presented. The primary purpose of the work was the identification and development of appropriate geotechnical descriptors and coefficients required for the Site Suitability Repository Model. This model was developed by The Analytic Sciences Corporation (TASC) of Reading, Massachusetts and is not described in this report

  18. Development of site suitability criteria for the high level waste repository for Lawrence Livermore Laboratories

    Energy Technology Data Exchange (ETDEWEB)

    1977-06-01

    Results of our mining, geological and geotechnical studies provided in support of the development of site suitability criteria for the high level waste repository are presented. The primary purpose of the work was the identification and development of appropriate geotechnical descriptors and coefficients required for the Site Suitability Repository Model. This model was developed by The Analytic Sciences Corporation (TASC) of Reading, Massachusetts and is not described in this report.

  19. Hydrogen transfer experiments and modelization in clay rocks for radioactive waste deep geological repository

    International Nuclear Information System (INIS)

    Boulin, P.

    2008-10-01

    Gases will be generated by corrosion of high radioactive waste containers in deep geological repositories. A gas phase will be generated. Gas pressure will build up and penetrated the geological formation. If gases do not penetrate the geological barrier efficiently, the pressure build up may create a risk of fracturing and of creation of preferential pathways for radionuclide migration. The present work focuses on Callovo-Oxfordian argillites characterisation. An experiment, designed to measure very low permeabilities, was used with hydrogen/helium and analysed using the Dusty Gas Model. Argillites close to saturation have an accessible porosity to gas transfer that is lower than 0,1% to 1% of the porosity. Analysis of the Knudsen effect suggests that this accessible network should be made of 50 nm to 200 nm diameter pores. The permeabilities values were integrated to an ANDRA operating model. The model showed that the maximum pressure expected near the repository would be 83 bar. (author)

  20. Derivation of parameters necessary for the evaluation of performance of sites for deep geological repositories with particular reference to bedded salt, Livermore, California. Volume I. Main text

    International Nuclear Information System (INIS)

    Ashby, J.P.; Rawlings, G.E.; Soto, C.A.; Wood, D.F.; Chorley, D.W.

    1979-12-01

    A survey of parameters to be considered in the evaluation of sites for deep geologic nuclear waste repositories is presented. As yet, no comprehensive site selection procedure or performance evaluation approach has been adopted. A basis is provided for the development of parameters by discussing both site selection and performance evaluation. Three major groups of parameters are considered in this report: geologic, mining/rock mechanics, and hydrogeologic. For each type, the role of the parameter in the evaluation of repository sites is discussed. The derivation of the parameter by measurement, correlation, inference, or other method is discussed. Geologic parameters define the framework of the repository site and can be used in development of conceptual models and the prediction of long-term performance. Methods for deriving geological parameters include mapping, surveying, drilling, geophysical investigation, and historical and regional analysis. Rock mechanics/mining parameters are essential for the prediction of short-term performance and the development of initial conditions for modeling of long-term performance. Rock mechanics/mapping parameters can be derived by field or laboratory investigation, correlation, and theoretically or empirically based inference. Hydrogeologic parameters are the most important for assessment of long-term radionuclide confinement, since transport throughout the regional hydrogeologic system is the most likely mode of radionuclide escape from geologic repositories. Hydrogeologic parameters can be derived by hydrogeologic mapping and interpretation, hydrogeologic system modeling, field measurements, and lab tests. Procedures used in determination and statistical evaluation of geologic and rock mechanics parameters are discussed

  1. Derivation of parameters necessary for the evaluation of performance of sites for deep geological repositories with particular reference to bedded salt, Livermore, California. Volume I. Main text

    Energy Technology Data Exchange (ETDEWEB)

    Ashby, J.P.; Rawlings, G.E.; Soto, C.A.; Wood, D.F.; Chorley, D.W.

    1979-12-01

    A survey of parameters to be considered in the evaluation of sites for deep geologic nuclear waste repositories is presented. As yet, no comprehensive site selection procedure or performance evaluation approach has been adopted. A basis is provided for the development of parameters by discussing both site selection and performance evaluation. Three major groups of parameters are considered in this report: geologic, mining/rock mechanics, and hydrogeologic. For each type, the role of the parameter in the evaluation of repository sites is discussed. The derivation of the parameter by measurement, correlation, inference, or other method is discussed. Geologic parameters define the framework of the repository site and can be used in development of conceptual models and the prediction of long-term performance. Methods for deriving geological parameters include mapping, surveying, drilling, geophysical investigation, and historical and regional analysis. Rock mechanics/mining parameters are essential for the prediction of short-term performance and the development of initial conditions for modeling of long-term performance. Rock mechanics/mapping parameters can be derived by field or laboratory investigation, correlation, and theoretically or empirically based inference. Hydrogeologic parameters are the most important for assessment of long-term radionuclide confinement, since transport throughout the regional hydrogeologic system is the most likely mode of radionuclide escape from geologic repositories. Hydrogeologic parameters can be derived by hydrogeologic mapping and interpretation, hydrogeologic system modeling, field measurements, and lab tests. Procedures used in determination and statistical evaluation of geologic and rock mechanics parameters are discussed.

  2. Radiation protection activities after closure of geological repositories

    International Nuclear Information System (INIS)

    Jensen, M.; Wallberg, P.

    2002-01-01

    Although the safety of repositories for radioactive waste should not depend of active controls such as monitoring, several control measures may be required for a variety of societal reasons. It is possible that the reporting of environmental monitoring to international treaties and conventions, already in place today, may be of value in meeting those requirements. To prepare for passive institutional control includes taking measures today that may be of use for future institutional control, including the possibility that future societies may initiate or renew active control measures. Passive institutional control may be of use to prevent or reduce the likelihood of human intrusion, to allow for remedial action, or to serve as a source of information in future societies, in the form of accurate historical documents. In the process of reporting within international conventions, including the most important reporting within the so-called Waste Convention, a large body of information will be built up by a process already in place today. This information is in itself a source for passive institutional control. (author)

  3. Architecture Design Issues of a Reversible Deep Geological Repository for HL and IL/LL Waste

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, C.; Londe, L.; Poisson, J.B. [Andra (France)

    2009-06-15

    In accordance with the Planning Act of 28 June 2006, the French National Radioactive Waste Management Agency (Agence nationale pour la gestion des dechets radioactifs - ANDRA) is currently investigating the possibility of disposing of high-level (HL) and intermediate-level long-lived (IL/LL) radioactive waste in a deep geological formation. The waste inventory intended for geological disposal is significant and represents approximately 80,000 m{sup 3} of primary waste. The required drifts and cells for such disposal are developing in a long and complex network, with plans calling for a total of about 300 km of drifts to be opened over the next century. This paper describes various issues relating to the architecture design and the way they are integrated. Long-term safety is at the basis of the major principles not only for dividing the different waste categories into separate disposal areas, but also for identifying the relevant constraints involving the topology of the network (fragmentation of disposal areas into modules, dead-end architecture) and the orientation of certain structures. In the case of exothermal waste, since the control over the phenomenological evolution also leads to selecting a thermal criterion in the geological layer in contact with the waste, there is an impact on the density of the repository and, consequently, on its architecture. Operational security and safety issues are reflected in ventilation needs and in personnel-evacuation requirements in case of fire, both of which require additional intersections and drifts. The section of drifts is also conditioned often by those security aspects. Nuclear zoning may also induce requirements for special structures having a potential impact on the architecture. Operation, taken into its broader sense encompassing construction and nuclear activities, imposes its own share of constraints quite independently from any security or safety considerations. Impacted areas include structure slopes, the

  4. Considerations on pressure build-up in deep geological repositories for radioactive waste

    International Nuclear Information System (INIS)

    Beer, Hans-Frieder

    2015-01-01

    Gas formation caused by corrosion of metals is a pivotal point with respect to the safety analysis of deep geological repositories. Solid corrosion products are formed unavoidably during the gas formation. The volumes of these solid corrosion products are multiples of the original waste volume. These solid corrosion products are chemically extremely stable and result in a pressure increase inside the repository. This pressure is considerably higher than that of the overlaying rock. The question that arises is, why this aspect is not considered in the consulted documents.

  5. Status of technologies related to the isolation of radioactive wastes in geologic repositories

    Energy Technology Data Exchange (ETDEWEB)

    Irish, E R [International Atomic Energy Agency, Vienna (Austria). Div. of Nuclear Safety and Environmental Protection; Cooley, C R [Department of Energy, Washington, DC (USA). Office of Nuclear Waste Management

    1980-09-01

    The authors present an overview of the status of technologies relevant to the isolation of radioactive wastes in geologic repositories. In addition to summarizing scientific and technical work on waste forms and packages, the: a) importance of the systems viewpoint, b) importance of modeling, c) need for site-specific investigations, d) consideration of future sub-surface human activities and e) prospects for successful isolation are discussed. It is concluded that successful isolation of radioactive wastes from the biosphere appears technically feasible for periods of thousands of years provided that the systems view is used in repository siting and design.

  6. Retrievability of high-level nuclear waste from geologic repositories - Regulatory and rock mechanics/design considerations

    International Nuclear Information System (INIS)

    Tanious, N.S.; Nataraja, M.S.; Daemen, J.J.K.

    1987-01-01

    Retrievability of nuclear waste from high-level geologic repositories is one of the performance objectives identified in 10CFR60 (Code of Federal Regulations, 1985). 10CFR60.111 states that the geologic repository operations area shall be designed to preserve the option of waste retrieval. In designing the repository operations area, rock mechanics considerations play a major role especially in evaluating the feasibility of retrieval operations. This paper discusses generic considerations affecting retrievability as they relate to repository design, construction, and operation, with emphasis on regulatory and rock mechanics aspects

  7. Diffusive Transport of Sulphide through an Engineering Barrier System in a Deep Geological Repository

    Science.gov (United States)

    Briggs, S. A.; Sleep, B. E.; McKelvie, J. R. M.; Krol, M.

    2015-12-01

    Bentonite is a naturally occurring clay-rich sediment containing montmorillonite, a smectitic clay mineral that has a high cation exchange capacity and swells upon contact with water. Owing to these characteristics, highly compacted bentonite (HCB) is an often included component of engineered barrier systems (EBS) designed to protect used fuel containers (UFCs) in deep geological repositories (DGR) for high-level nuclear waste. The low water activity and high swelling pressure of HCB suppresses microbial activity and the related production of sulphide that could cause microbiologically influenced corrosion (MIC) of UFCs The Canadian Nuclear Waste Management Organization (NWMO) has chosen a UFC that consists of an inner steel core and outer copper coating which is resistant to corrosion. However, under anaerobic conditions, MIC can still contribute to UFC corrosion if sulphides are present in the groundwater. Therefore the EBS consisting of bentonite blocks and pellets has been designed to impede the movement of sulphides to the UFC. In order to examine the effectiveness of the EBS, a 3D numerical model was developed capable of simulating the diffusive transport of sulphide within the NWMO EBS. The model was developed using COMSOL Multiphysics, a finite element software package and is parametric which allows the impact of different repository layouts to be assessed. The developed model was of the entire NWMO placement room, as well as, a stand-alone UFC and included conservative assumptions such as a fully saturated system and a constant concentration boundary condition. The results showed that the highest sulphide flux occurred at the semi-spherical end caps of the UFC. Further studies examined the effect of sulphide hotspots and fractures, representing possible EBS failure mechanisms. The model results highlight that even with conservative assumptions the chosen EBS will effectively protect the UFC from microbiologically influenced corrosion.

  8. Redox processes in the safety case of deep geological repositories of radioactive wastes. Contribution of the European RECOSY Collaborative Project

    International Nuclear Information System (INIS)

    Duro, L.; Bruno, J.; Grivé, M.; Montoya, V.; Kienzler, B.; Altmaier, M.; Buckau, G.

    2014-01-01

    Highlights: • The RECOSY project produced results relevant for the Safety Case of nuclear disposal. • We classify the safety related features where RECOSY has contributed. • Redox processes effect the retention of radionuclides in all repository subsystems. - Abstract: Redox processes influence key geochemical characteristics controlling radionuclide behaviour in the near and far field of a nuclear waste repository. A sound understanding of redox related processes is therefore of high importance for developing a Safety Case, the collection of scientific, technical, administrative and managerial arguments and evidence in support of the safety of a disposal facility. This manuscript presents the contribution of the specific research on redox processes achieved within the EURATOM Collaborative Project RECOSY (REdox phenomena COntrolling SYstems) to the Safety Case of nuclear waste disposal facilities. Main objectives of RECOSY were related to the improved understanding of redox phenomena controlling the long-term release or retention of radionuclides in nuclear waste disposal and providing tools to apply the results to Performance Assessment and the Safety Case. The research developed during the project covered aspects of the near-field and the far-field aspects of the repository, including studies relevant for the rock formations considered in Europe as suitable for hosting an underground repository for radioactive wastes. It is the intention of this paper to highlight in which way the results obtained from RECOSY can feed the scientific process understanding needed for the stepwise development of the Safety Case associated with deep geological disposal of radioactive wastes

  9. Geotechnical support and topical studies for nuclear waste geologic repositories

    International Nuclear Information System (INIS)

    1990-12-01

    This multidisciplinary project was initiated in fiscal year 1986. It comprises two major interrelated tasks, technical assistance and topical studies. The present report lists the technical reviews and comments made during the fiscal year 1989 and summarizes the technical progress of the topical studies. The major task was a study of the mechanical, hydraulic, geophysical and geochemical properties of fractures in geologic rock masses. In the area of technical assistance, there were a total of 30 geotechnical support activities, including reviews of 15 study plans (SP) and participation in 5 SP Review Workshops; in-depth multidisciplinary review of 5 Exploratory Shaft Facility (ESF) Study Plans and presentation of results to DOE; preparation and revision of a white paper and proposed work statement on preclosure monitoring and performance confirmation as an outgrowth of a request made by DOE to LBL; the hosting of a DOE program review; with DOE's encouragement, preparation of 8 papers for the International High-Level Radioactive Waste Management Conference to be held in April, 1990 in Las Vegas, Nevada; and 5 instances of general technical assistance to DOE

  10. Mathematical modelling of heat production in deep geological repository of high-level nuclear waste

    International Nuclear Information System (INIS)

    Kovanda, O.

    2017-01-01

    Waste produced by nuclear industry requires special handling. Currently, there is a research taking place, focused at possibilities of nuclear waste storage in deep geological repositories, hosted in stable geological environment. The high-level nuclear waste produces significant amount of heat for a long time, which can affect either environment outside of or within the repository in a negative way. Therefore to reduce risks, it is desirable to know the principles of such heat production, which can be achieved using mathematical modeling. This thesis comes up with a general model of heat production-time dependency, dependable on initial composition of the waste. To be able to model real situations, output of this thesis needs to be utilized in an IT solution. (authors)

  11. Standard guide for characterization of spent nuclear fuel in support of geologic repository disposal

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This guide provides guidance for the types and extent of testing that would be involved in characterizing the physical and chemical nature of spent nuclear fuel (SNF) in support of its interim storage, transport, and disposal in a geologic repository. This guide applies primarily to commercial light water reactor (LWR) spent fuel and spent fuel from weapons production, although the individual tests/analyses may be used as applicable to other spent fuels such as those from research and test reactors. The testing is designed to provide information that supports the design, safety analysis, and performance assessment of a geologic repository for the ultimate disposal of the SNF. 1.2 The testing described includes characterization of such physical attributes as physical appearance, weight, density, shape/geometry, degree, and type of SNF cladding damage. The testing described also includes the measurement/examination of such chemical attributes as radionuclide content, microstructure, and corrosion product c...

  12. Limits on the thermal energy release from radioactive wastes in a mined geologic repository

    International Nuclear Information System (INIS)

    Scott, J.A.

    1983-03-01

    The theraml energy release of nuclear wastes is a major factor in the design of geologic repositories. Thermal limits need to be placed on various aspets of the geologic waste disposal system to avoid or retard the degradation of repository performance because of increased temperatures. The thermal limits in current use today are summarized in this report. These limits are placed in a hierarchial structure of thermal criteria consistent with the failure mechanism they are trying to prevent. The thermal criteria hierarchy is used to evaluate the thermal performance of a sample repository design. The design consists of disassembled BWR spent fuel, aged 10 years, close packed in a carbon steel canister with 15 cm of crushed salt backfill. The medium is bedded salt. The most-restrictive temperature for this design is the spent-fuel centerline temperature limit of 300 0 C. A sensitivity study on the effects of additional cooling prior to disposal on repository thermal limits and design is performed

  13. NAGRA - Sites for geological repositories - Technical safety factors: Suggestions for stage 3

    International Nuclear Information System (INIS)

    2015-01-01

    This comprehensive brochure published by the Swiss National Cooperative for the Disposal of Radioactive Waste (NAGRA) examines the six sites for repositories for nuclear wastes in Switzerland which have been proposed in Stage 1 of the program concerning nuclear waste repositories. Three of these sites are proposed for both highly radioactive wastes as well as for low and medium-active wastes, the other three for low and medium-active wastes only. The evaluation of the sites is discussed. The sites are to be further evaluated in Stage 2 of the program. The work to be done in the further stages involved in the selection of the final site (or sites) is described. Along with definition of the regions where deep repositories could possibly be built, suggestions for the placing of the facilities required on the surface are discussed. Geological requirements on the repositories and safety-relevant characteristics of the various site options are discussed. The results of the assessments made are presented in tabular form. Maps and geological cross-sections of all the suggested areas are included

  14. 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

  15. Logistics Modeling of Emplacement Rate and Duration of Operations for Generic Geologic Repository Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Kalinina, Elena Arkadievna; Hardin, Ernest

    2015-11-01

    This study identified potential geologic repository concepts for disposal of spent nuclear fuel (SNF) and (2) evaluated the achievable repository waste emplacement rate and the time required to complete the disposal for these concepts. Total repository capacity is assumed to be approximately 140,000 MT of spent fuel. The results of this study provide an important input for the rough-order-of-magnitude (ROM) disposal cost analysis. The disposal concepts cover three major categories of host geologic media: crystalline or hard rock, salt, and argillaceous rock. Four waste package sizes are considered: 4PWR/9BWR; 12PWR/21BWR; 21PWR/44BWR, and dual purpose canisters (DPCs). The DPC concepts assume that the existing canisters will be sealed into disposal overpacks for direct disposal. Each concept assumes one of the following emplacement power limits for either emplacement or repository closure: 1.7 kW; 2.2 kW; 5.5 kW; 10 kW; 11.5 kW, and 18 kW.

  16. Logistics Modeling of Emplacement Rate and Duration of Operations for Generic Geologic Repository Concepts

    International Nuclear Information System (INIS)

    Kalinina, Elena Arkadievna; Hardin, Ernest

    2015-01-01

    This study identified potential geologic repository concepts for disposal of spent nuclear fuel (SNF) and (2) evaluated the achievable repository waste emplacement rate and the time required to complete the disposal for these concepts. Total repository capacity is assumed to be approximately 140,000 MT of spent fuel. The results of this study provide an important input for the rough-order-of-magnitude (ROM) disposal cost analysis. The disposal concepts cover three major categories of host geologic media: crystalline or hard rock, salt, and argillaceous rock. Four waste package sizes are considered: 4PWR/9BWR; 12PWR/21BWR; 21PWR/44BWR, and dual purpose canisters (DPCs). The DPC concepts assume that the existing canisters will be sealed into disposal overpacks for direct disposal. Each concept assumes one of the following emplacement power limits for either emplacement or repository closure: 1.7 kW; 2.2 kW; 5.5 kW; 10 kW; 11.5 kW, and 18 kW.

  17. 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)

  18. Impact of advanced fuel cycles on uncertainty associated with geologic repositories

    International Nuclear Information System (INIS)

    Rechard, Rob P.; Lee, Joon; Sutton, Mark; Greenberg, Harris R.; Robinson, Bruce A.; Nutt, W. Mark

    2013-01-01

    This paper provides a qualitative evaluation of the impact of advanced fuel cycles, particularly partition and transmutation of actinides, on the uncertainty associated with geologic disposal. Based on the discussion, advanced fuel cycles, will not materially alter (1) the repository performance (2) the spread in dose results around the mean (3) the modeling effort to include significant features, events, and processes in the performance assessment, or (4) the characterization of uncertainty associated with a geologic disposal system in the regulatory environment of the United States. (authors)

  19. Continuous Improvement and the Safety Case for the Waste Isolation Pilot Plant Geologic Repository - 13467

    Energy Technology Data Exchange (ETDEWEB)

    Van Luik, Abraham; Patterson, Russell; Nelson, Roger [US Department of Energy, Carlsbad Field Office, 4021 S. National parks Highway, Carlsbad, NM 88220 (United States); Leigh, Christi [Sandia National Laboratories Carlsbad Operations, 4100 S. National parks Highway, Carlsbad, NM 88220 (United States)

    2013-07-01

    The Waste Isolation Pilot Plant (WIPP) is a geologic repository 2150 feet (650 m) below the surface of the Chihuahuan desert near Carlsbad, New Mexico. WIPP permanently disposes of transuranic waste from national defense programs. Every five years, the U.S. Department of Energy (DOE) submits an application to the U.S. Environmental Protection Agency (EPA) to request regulatory-compliance re-certification of the facility for another five years. Every ten years, DOE submits an application to the New Mexico Environment Department (NMED) for the renewal of its hazardous waste disposal permit. The content of the applications made by DOE to the EPA for re-certification, and to the NMED for permit-renewal, reflect any optimization changes made to the facility, with regulatory concurrence if warranted by the nature of the change. DOE points to such changes as evidence for its having taken seriously its 'continuous improvement' operations and management philosophy. Another opportunity for continuous improvement is to look at any delta that may exist between the re-certification and re-permitting cases for system safety and the consensus advice on the nature and content of a safety case as being developed and published by the Nuclear Energy Agency's Integration Group for the Safety Case (IGSC) expert group. DOE at WIPP, with the aid of its Science Advisor and teammate, Sandia National Laboratories, is in the process of discerning what can be done, in a reasonably paced and cost-conscious manner, to continually improve the case for repository safety that is being made to the two primary regulators on a recurring basis. This paper will discuss some aspects of that delta and potential paths forward to addressing them. (authors)

  20. 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

  1. 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

  2. Site selection for deep geologic repositories - Consequences for society, economy and environment; was kommt auf die regionen zu? Auswirkungen geologischer tiefenlager auf gesellschaft, wirtschaft und lebensraum

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-03-15

    In a few years, Switzerland will make the decision regarding site selection for geological underground repositories for the storage of radioactive wastes. Besides the safety issue, many citizens are interested in how such a repository will affect environment, economy and society in the selected site's region. This brochure summarizes the results of many studies on the socio-economic impacts of nuclear waste repositories. Radioactive wastes must be stored in such a way that mankind and environment are safely protected for a long period of time. How this goal may be achieved, is already known: geologic deep repositories warrant long-term safety. For the oncoming years in Switzerland the question is where the repository will be built. The search for an appropriate site for a repository in the proposed regions will launch discussions. Within the participative framework the regions may bring their requests. The demonstration of the safety of potential repository sites has the highest priority in the selection process. In the third procedural step additional rock investigations will be made. The socio-economic studies and the experience with existing plants show that radioactive waste management plants can be built and operated in good agreement with environmental requirements. The radioactive wastes in a deep underground repository are stored many hundred meters below the Earth's surface. There, they are isolated from our vital space. Technical barriers and the surrounding dense rock confinement prevent the release of radioactive materials into the environment. A deep repository has positive consequences for the regional economy. It increases trade and value creation and creates work places. The socio-economic impacts practically extend over one century, but strongly vary with time; they are the largest during the building period. High life quality and a positive population development in the selected site region are compatible with a deep repository. A fair

  3. Summary of key directives governing permanent disposal in a geologic repository

    International Nuclear Information System (INIS)

    Sands, S.C. III.

    1993-11-01

    This document was developed in support of the Idaho National Engineering Laboratory (INEL) Spent Fuel and Waste Management Technology Development Program (SF ampersand WMTDP). It is largely comprised of flow diagrams summarizing the key regulatory requirements which govern permanent disposal in a geologic repository. The key purposes are (1) to provide an easy and effective tool for referencing or cross referencing federal directives (i.e., regulations and orders), (2) to provide a method for examining the requirements in one directive category against the requirements in another, and (3) to list actions that must be taken to ensure directive compliance. The document is categorically broken down into a Transportation section and a Mined Geologic Disposal System (MGDS) section to ensure that the interrelationship of the entire disposal system is considered. The Transportation section describes the transportation packaging requirements, testing methods, and safety requirements imposed on fissile material shipments. The MGDS section encompasses technical aspects involved in siting, licensing, waste interaction with the container, container design features, physical characteristics of the surrounding environment, facility design features, barrier systems, safety features, criticality considerations, migration restrictions, implementation guidelines, and so forth. For purposes of illustration, the worst case scenario is outlined. It is important that the approaches and considerations contained in this document be integrated into the efforts of the SF ampersand WMTDP so that every applicable aspect of the regulatory requirements can be evaluated to avoid investing large sums of money into projects that do not take into account all of the aspects of permanent waste disposal. Not until an overall picture and clear understanding of these regulations is established can a basis be developed to govern the direction of future activities of the SF ampersand WMTDP

  4. Approach to resolution of geologic uncertainty in the licensing of a high-level-waste repository in tuff

    International Nuclear Information System (INIS)

    Neal, J.T.

    1983-01-01

    Resolution of uncertainty in geological information is an essential element in the licensing process for a geologic repository. Evaluation of these uncertainties within the licensing framework established by the Nuclear Regulatory Commission (NRC) is required. The Nevada Nuclear Waste Storage Investigations (NNWSI), in focusing its site characterization program on unsaturated tuff, has developed a logic hierarchy of technical issues, including key issues, issues, and information needs. Key issues are statements of major requirements whose lack could be disqualifying. An example of a key issue is the demonstration of radionuclide containment and isolation within the required release limits and transport time set by the EPA and NRC. Key issues are broken down into issues, such as the groundwater flow time to the accessible environment. Resolving uncertainty ultimately comes back to satisfying individual information needs that collectively form issues. Hydraulic conductivity is an example of an information need required to determine groundwater flow rate. Sources of uncertainty often arise in either amount, quality, or other limitations in geological data. The hierarchical structuring of geological information needs provides a perspective that allows proportionate attention to be placed on various site characterization activities, and to view them within the whole range of licensing issues that must be satisfied to ensure public health and safety. However, it may not prevent an issue from being contentious, as some geological questions are known to be emotion-laden. The mitigation of uncertainty in geological information ultimately will depend on the validity and credibility of the information presented during the licensing process

  5. Use of petrophysical data for siting of deep geological repository of radioactive waste

    Science.gov (United States)

    Petrenko, Liliana; Shestopalov, Vyacheslav

    2017-11-01

    The paper is devoted to analyzing the petrophysical properties and petrographical characteristics of Volyn region with the view to choosing the least permeable and so the most suitable geological formation for the radioactive waste disposal. On a basis of the petrophysical estimations of the granitoids properties the argumentation of permeability has been developed for the petrotypes of Volyn region. Also method of classification of the petrotypes with their relative rate of suitability for radioactive waste disposal was developed. As a result of studying the perspectives were shown of the zhytomyr and korosten types of the granitoids as host rock for the radioactive waste disposal. According to the results of investigations performed by Swedish researchers a comparative analysis of rocks based on the age of formation, composition, structural features and some petrophysical properties of granitoids as host rocks for repository of radioactive waste was performed. Detail comparison the data of the granitoids of the Forsmark site in Sweden and the data of the granitoids of the Volyn megablock can be one of the next steps in researching the host rocks for the development of the RW disposal system in Ukraine.

  6. Use of petrophysical data for siting of deep geological repository of radioactive waste

    Directory of Open Access Journals (Sweden)

    Petrenko Liliana

    2017-01-01

    Full Text Available The paper is devoted to analyzing the petrophysical properties and petrographical characteristics of Volyn region with the view to choosing the least permeable and so the most suitable geological formation for the radioactive waste disposal. On a basis of the petrophysical estimations of the granitoids properties the argumentation of permeability has been developed for the petrotypes of Volyn region. Also method of classification of the petrotypes with their relative rate of suitability for radioactive waste disposal was developed. As a result of studying the perspectives were shown of the zhytomyr and korosten types of the granitoids as host rock for the radioactive waste disposal. According to the results of investigations performed by Swedish researchers a comparative analysis of rocks based on the age of formation, composition, structural features and some petrophysical properties of granitoids as host rocks for repository of radioactive waste was performed. Detail comparison the data of the granitoids of the Forsmark site in Sweden and the data of the granitoids of the Volyn megablock can be one of the next steps in researching the host rocks for the development of the RW disposal system in Ukraine.

  7. Selection of nuclide decay chains for use in the assessment of the radiological impact of geological repositories for radioactive waste

    International Nuclear Information System (INIS)

    Thorne, M.C.

    1982-12-01

    The criteria for selecting nuclide decay chains for use in the assessment of the radiological impact of geological repositories for radioactive waste are given. The reduced chains recommended for use with SYVAC are described. (author)

  8. Study on the development of geological environmental model

    International Nuclear Information System (INIS)

    Tsujimoto, Keiichi; Shinohara, Yoshinori; Ueta, Shinzo; Saito, Shigeyuki; Kawamura, Yuji; Tomiyama, Shingo; Ohashi, Toyo

    2002-03-01

    The safety performance assessment was carried out in potential geological environment in the conventional research and development of geological disposal, but the importance of safety assessment based on the repository design and scenario considering the concrete geological environment will increase in the future. The research considering the link of the major three fields of geological disposal, investigation of geological environment, repository design, and safety performance assessment, is the contemporary worldwide research theme. Hence it is important to organize information flow that contains the series of information process form the data production to analysis in the three fields, and to systemize the knowledge base that unifies the information flow hierarchically. The purpose of the research is to support the development of the unified analysis system for geological disposal. The development technology for geological environmental model studied for the second progress report by JNC are organized and examined for the purpose of developing database system with considering the suitability for the deep underground research facility. The geological environmental investigation technology and building methodology for geological structure and hydro geological structure models are organized and systemized. Furthermore, the quality assurance methods in building geological environment models are examined. Information which is used and stored in the unified analysis system are examined to design database structure of the system based on the organized methodology for building geological environmental model. The graphic processing function for data stored in the unified database are examined. furthermore, future research subjects for the development of detail models for geological disposal are surveyed to organize safety performance system. (author)

  9. Monitoring feasibility of ILW cell for geologic repository

    International Nuclear Information System (INIS)

    Farhoud, R.; Bertrand, J.; Buschaert, S.; Delepine-Lesoille, S.; Hermand, G.; De Combarieu, M.; Dubois, J.P.

    2012-01-01

    Document available in extended abstract form only. In addition to the operational safety system, Andra has planned to install a monitoring system for observing phenomenological evolutions, to support i) the periodic re-evaluation of the long-term safety of Cigeo (future industrial plant for geological disposal), ii) the reversibility management, iii) the evaluation of structural health and iv) the improvement of design for further cells. Underground disposal for ILW (Intermediate-level Long lived) Wastes, in clay host material, could be long cells of some hundreds of meters and about 8-12 m in diameter with concrete liners. Some of these tunnels would be intensively monitored during disposal exploitation without any maintenance. Andra's monitoring strategy aims to qualify the selected monitoring technologies in 4 steps to ensure reliability, durability, and metrological performance of sensing chains. First, existing sensors and their characteristics have been inventoried. Then, tests in well-known conditions in laboratory are performed before in situ tests. In parallel, hardening to radiations and metrological survey achieve the qualification of the instrument. To test the monitoring section dedicates to ILW cell and to tackle the difficulties of on-site instrumentation, Andra have conducted a specific experimentation during the autumn 2011 in the Andra's underground research laboratory (URL). This paper describes the experiment and show the primary results obtained. Within the global experimentation ORS (observation of liners and supporting structure) in Andra URL, a representative monitoring system of a possible approach has been implemented, with the following goals: - Test implementation protocols of sensors, especially for innovative technologies (like optical fibers or in situ water content sensors-) - Validate in situ sensors technology redundancy and complementarity to provide global structural health monitoring from thermal, hydraulic and mechanical (T

  10. Reducing the likelihood of future human activities that could affect geologic high-level waste repositories

    International Nuclear Information System (INIS)

    1984-05-01

    The disposal of radioactive wastes in deep geologic formations provides a means of isolating the waste from people until the radioactivity has decayed to safe levels. However, isolating people from the wastes is a different problem, since we do not know what the future condition of society will be. The Human Interference Task Force was convened by the US Department of Energy to determine whether reasonable means exist (or could be developed) to reduce the likelihood of future human unintentionally intruding on radioactive waste isolation systems. The task force concluded that significant reductions in the likelihood of human interference could be achieved, for perhaps thousands of years into the future, if appropriate steps are taken to communicate the existence of the repository. Consequently, for two years the task force directed most of its study toward the area of long-term communication. Methods are discussed for achieving long-term communication by using permanent markers and widely disseminated records, with various steps taken to provide multiple levels of protection against loss, destruction, and major language/societal changes. Also developed is the concept of a universal symbol to denote Caution - Biohazardous Waste Buried Here. If used for the thousands of non-radioactive biohazardous waste sites in this country alone, a symbol could transcend generations and language changes, thereby vastly improving the likelihood of successful isolation of all buried biohazardous wastes

  11. Validation of TEMP: A finite line heat transfer code for geologic repositories for nuclear waste

    International Nuclear Information System (INIS)

    Atterbury, W.G.; Hetteburg, J.R.; Wurm, K.J.

    1987-09-01

    TEMP is a FORTRAN computer code for calculating temperatures in a geologic repository for nuclear waste. A previous report discusses the structure, usage, verification, and benchmarking of TEMP V1.0 (Wurm et al., 1987). This report discusses modifications to the program in the development of TEMP V1.1 and documents the validation of TEMP. The development of TEMP V1.1 from TEMP V1.0 consisted of two major efforts. The first was to recode several of the subroutines to improve logic flow and to allow for geometry-independent temperature calculation routines which, in turn, allowed for the addition of the geometry-independent validation option. The validation option provides TEMP with the ability to model any geometry of temperature sources with any step-wise heat release rate. This capability allows TEMP to model the geometry and heat release characteristics of the validation problems. The validation of TEMP V1.1 consists of the comparison of TEMP to three in-ground heater tests. The three tests chosen were Avery Island, Louisiana, Site A; Avery Island, Louisiana, Site C; and Asse Mine, Federal Republic of Germany, Site 2. TEMP shows marginal comparison with the two Avery Island sites and good comparison with the Asse Mine Site. 8 refs., 25 figs., 14 tabs

  12. Reducing the likelihood of future human activities that could affect geologic high-level waste repositories

    Energy Technology Data Exchange (ETDEWEB)

    1984-05-01

    The disposal of radioactive wastes in deep geologic formations provides a means of isolating the waste from people until the radioactivity has decayed to safe levels. However, isolating people from the wastes is a different problem, since we do not know what the future condition of society will be. The Human Interference Task Force was convened by the US Department of Energy to determine whether reasonable means exist (or could be developed) to reduce the likelihood of future human unintentionally intruding on radioactive waste isolation systems. The task force concluded that significant reductions in the likelihood of human interference could be achieved, for perhaps thousands of years into the future, if appropriate steps are taken to communicate the existence of the repository. Consequently, for two years the task force directed most of its study toward the area of long-term communication. Methods are discussed for achieving long-term communication by using permanent markers and widely disseminated records, with various steps taken to provide multiple levels of protection against loss, destruction, and major language/societal changes. Also developed is the concept of a universal symbol to denote Caution - Biohazardous Waste Buried Here. If used for the thousands of non-radioactive biohazardous waste sites in this country alone, a symbol could transcend generations and language changes, thereby vastly improving the likelihood of successful isolation of all buried biohazardous wastes.

  13. Sectoral Plan 'Deep Geological Disposal', Stage 2. Proposed site areas for the surface facilities of the deep geological repositories as well as for their access infrastructure. Annexes

    International Nuclear Information System (INIS)

    2011-12-01

    In line with the provisions of the nuclear energy legislation, the sites for deep geological disposal of Swiss radioactive waste are selected in a three-stage Sectoral Plan process (Sectoral Plan for Deep Geological Disposal). The disposal sites are specified in Stage 3 of the selection process with the granting of a general licence in accordance with the Nuclear Energy Act. The first stage of the process was completed on 30 th November 2011, with the decision of the Federal Council to incorporate the six geological siting regions proposed by the National Cooperative for the Disposal of Radioactive Waste (NAGRA) into the Sectoral Plan for Deep Geological Disposal, for further evaluation in Stage 2. The decision also specifies the planning perimeters within which the surface facilities and shaft locations for the repositories will be constructed. In the second stage of the process, at least two geological siting regions each will be specified for the repository for low- and intermediate-level waste (L/ILW) and for the high-level waste (HLW) repository and these will undergo detailed geological investigation in Stage 3. For each of these potential siting regions, at least one location for the surface facility and a corridor for the access infrastructure will also be specified. NAGRA is responsible, at the beginning of Stage 2, for submitting proposals for potential locations for the surface facilities and their access infrastructure to the Federal Office of Energy (SFOE); these are then considered by the regional participation bodies in the siting regions. The general report and the present annexes volume document these proposals. In Stage 2, under the lead of the SFOE, socio-economic-ecological studies will also be carried out to investigate the impact of a repository project on the environment, economy and society. The present reports also contain the input data to be provided by NAGRA for the generic (site-independent) part of these impact studies. A meaningful

  14. Territorial integration of the geological repository in France

    International Nuclear Information System (INIS)

    Farin, S.; Ouzounian, G.; Miguez, R.; Tison, J.-L.

    2011-01-01

    In France, a framework has been drawn up by the National Assembly and implemented by the government, in order to get the best relationship between Andra, among others, and the stakeholders and the inhabitants of the towns and countries where disposal facilities or projects are or could be established. The main threads of the two Acts passed in 2006, being relevant to the relationship with inhabitants are the information exchange and the local economic development. Dealing with the information exchange and diffusion: The Local Information Committee (CLI), for each nuclear facility, has been reinforced and a specific, Local Information and Oversight Committee (for the Underground Laboratory in Meuse-Haute-Marne) has been renewed. The CLI was in charge of a general assignment to inform and consult on nuclear safety, radioprotection and environmental topics. Now, since 2006, the nuclear facility's CLI and the CLIS are able to order study reports, measures and analyses to experts freely selected. Creation of the High Committee for Transparency and Information on Nuclear Safety (HCTISN). This new authority aims to inform, consult and debate about the risks relevant to nuclear activities and their impacts on people's health, environment and nuclear safety. Andra contributes to the functioning of CLI in disposal facilities at Manche and Aube Departments, and CLIS of the underground Laboratory at Meuse and Haute-Marne departments. This paper will present these contributions and how Andra's action helps to reach the goals of information and exchange with the people around its facilities. Concerning the local economic development, there are specific organizations or schemes, depending on the facility: Local taxes contributions based on the disposal facilities activities as is usual in France. A High Level Committee (CHN) and two public interest groups (GIP) in Meuse and Haute-Marne departments have been set up since 1991 and 2005. Andra is represented in these three

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

    International Nuclear Information System (INIS)

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

    2016-12-01

    In a deep geological repository for radioactive waste, in absence of oxygen and in presence of water, corrosion of various metals and alloys will lead to the formation of hydrogen. If present, organic materials may slowly degrade and generate carbon dioxide, methane and other gaseous species. Depending on local conditions, gaseous species can be consumed by chemical reactions and by microbial activity. If the resulting rate of gas generation exceeds the rate of migration of dissolved gas molecules in the pores of the engineered barriers or the host rock, the solubility limit of the gas will eventually be exceeded and the formation of a discrete gas phase will occur. Gases could continue to accumulate until the pressure becomes sufficient to be released in gaseous form. This report deals with the evolution of gas-related processes that can influence the long-term behaviour and safety of low- and intermediate-level waste (L/ILW) and high-level waste (HLW) repositories in Opalinus Clay. The main aim is to present a synthesis of processes and phenomena related to repository-produced gases and to assess their influence on repository performance. A current overview of gas sources, reactions and interactions, generation, consumption, and transport is provided. Furthermore, current scientific understanding is used to define safety function indicators and criteria, which are employed to evaluate the potential influence of repository-generated gas on safety-relevant properties of engineered and natural barriers. The assessment of gas generation, consumption and transport is addressed separately for the HLW and the L/ILW deep geological repositories. The employed methodology, which is common for both repository types, consists of the description and quantification of the potential gas sources, which include the waste, barrier components such as disposal canisters and other gas-generating repository components, and of the processes and reactions leading to the generation or

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-12-15

    In a deep geological repository for radioactive waste, in absence of oxygen and in presence of water, corrosion of various metals and alloys will lead to the formation of hydrogen. If present, organic materials may slowly degrade and generate carbon dioxide, methane and other gaseous species. Depending on local conditions, gaseous species can be consumed by chemical reactions and by microbial activity. If the resulting rate of gas generation exceeds the rate of migration of dissolved gas molecules in the pores of the engineered barriers or the host rock, the solubility limit of the gas will eventually be exceeded and the formation of a discrete gas phase will occur. Gases could continue to accumulate until the pressure becomes sufficient to be released in gaseous form. This report deals with the evolution of gas-related processes that can influence the long-term behaviour and safety of low- and intermediate-level waste (L/ILW) and high-level waste (HLW) repositories in Opalinus Clay. The main aim is to present a synthesis of processes and phenomena related to repository-produced gases and to assess their influence on repository performance. A current overview of gas sources, reactions and interactions, generation, consumption, and transport is provided. Furthermore, current scientific understanding is used to define safety function indicators and criteria, which are employed to evaluate the potential influence of repository-generated gas on safety-relevant properties of engineered and natural barriers. The assessment of gas generation, consumption and transport is addressed separately for the HLW and the L/ILW deep geological repositories. The employed methodology, which is common for both repository types, consists of the description and quantification of the potential gas sources, which include the waste, barrier components such as disposal canisters and other gas-generating repository components, and of the processes and reactions leading to the generation or

  17. Waste package transfer, emplacement and retrievability in the French deep geological repository

    Energy Technology Data Exchange (ETDEWEB)

    Roulet, Alain; Delort, Daniel; Herve, Jean Francois; Bosgiraud, Jean Michel; Guenin, Jean Jacques [Technical Department ANDRA (France)

    2009-06-15

    Safe, reliable and reversible handling of waste is a significant issue related to the design and safety assessment of deep geological repository in France. The first step taken was to study various waste handling solutions. ANDRA also decided to fabricate and demonstrate industrial scale handling equipment for HLW (since 2003) and for ILW-LL wastes (since 2008). We will review the main equipment developed for the transfer process in the repository, for both types of waste, and underline the benefits of developing industrial demonstrators within the framework of international cooperation agreements. Waste retrieval capability will be simultaneously examined. Two types of waste have to be handled underground in Andra's repository. The HLW disposal package for vitrified waste is a 2 ton carbon steel cylindrical canister with a diameter of 600 mm. The weight of ILW-LL concrete disposal packages range from a minimum of 6 tonnes to over 20 tonnes, and their volume from approximately 5 to 10 m3. The underground transfer to the disposal drift requires moving the disposal package within a shielded transfer cask placed on a trailer. Transfer cask design has evolved since 2005, due to optimisation studies and as a result of industrial feedback from SKB. For HLW handling equipment two design options have been studied. In the first solution (Andra's Dossier 2005), the waste package are emplaced, one at a time, in the disposal drift by a pushing robot. Successive steps in design and proto-typing have lead to improve the design of the equipment and to gain confidence. Recently a fully integrated process has been successfully demonstrated, at full scale, (in a 100 m long mock up drift) as part of the EC funded ESDRED Project. This demonstrator is now on display in Andra's Technology Centre at Saudron, near the Bure Underground Laboratory. The second disposal option which has been investigated is based on a concept of utilising an external apparatus to push a row of

  18. Impact of transporting defense high-level waste to a geologic repository

    International Nuclear Information System (INIS)

    Joy, D.S.; Shappert, L.B.; Boyle, J.W.

    1984-12-01

    The Nuclear Waste Policy Act of 1982 (Public Law 97-425) provides for the development of repositories for the disposal of high-level radioactive waste and spent nuclear fuel and requires the Secretary of Energy to evaluate five potential repository sites. One factor that is to be examined is transportation of radioactive materials to such a repository and whether transportation might be affected by shipments to a defense-only repository, or to one that accepts both defense and commercial waste. In response to this requirement, The Department of Energy has undertaken an evaluation of the cost and risk associated with the potential shipments. Two waste-flow scenarios are considered which are related to the total quantity of defense high-level waste which will be placed in a repository. The low-flow case is based on a total of 6700 canisters being transported from one site, while the high-flow case assumes that a total of 20,000 canisters will be transported from three sites. For the scenarios considered, the estimated shipping costs range from $105 million to $257 million depending upon the mode of transport and the repository location. The total risks associated with shipping defense high-level waste to a repository are estimated to be significantly smaller than predicted for other transportation activities. In addition, the cost of shipping defense high-level waste to a repository does not depend on whether the site is a defense-only or a commercial repository. Therefore, the transportation considerations are not a basis for the selection of one of the two disposal options

  19. Sectoral Plan 'Deep Geological Disposal', Stage 2. Proposed site areas for the surface facilities of the deep geological repositories as well as for their access infrastructure. General report

    International Nuclear Information System (INIS)

    2011-12-01

    In line with the provisions of the nuclear energy legislation, the sites for deep geological disposal of Swiss radioactive waste are selected in a three-stage Sectoral Plan process (Sectoral Plan for Deep Geological Disposal). The disposal sites are specified in Stage 3 of the selection process with the granting of a general licence in accordance with the Nuclear Energy Act. The first stage of the process was completed on 30 th November 2011, with the decision of the Federal Council to incorporate the six geological siting regions proposed by the National Cooperative for the Disposal of Radioactive Waste (NAGRA) into the Sectoral Plan for Deep Geological Disposal, for further evaluation in Stage 2. The decision also specifies the planning perimeters within which the surface facilities and shaft locations for the repositories will be constructed. In the second stage of the process, at least two geological siting regions each will be specified for the repository for low- and intermediate-level waste (L/ILW) and for the high-level waste (HLW) repository and these will undergo detailed geological investigation in Stage 3. For each of these potential siting regions, at least one location for the surface facility and a corridor for the access infrastructure will also be specified. NAGRA is responsible, at the beginning of Stage 2, for submitting proposals for potential locations for the surface facilities and their access infrastructure to the Federal Office of Energy (SFOE); these are then considered by the regional participation bodies in the siting regions. The present report and its annexes volume document these proposals. In Stage 2, under the lead of the SFOE, socio-economic-ecological studies will also be carried out to investigate the impact of a repository project on the environment, economy and society. The present reports also contain the input data to be provided by NAGRA for the generic (site-independent) part of these impact studies. A meaningful discussion

  20. Site investigations for repositories for solid radioactive wastes in deep continental geological formations

    International Nuclear Information System (INIS)

    1982-01-01

    This report reviews the earth-science investigations and associated scientific studies that may be needed to select a repository site and confirm that its characteristics are such that it will provide a safe confinement for solidified high-level and alpha-bearing and certain other solid radioactive wastes. Site investigations, as used in this report, cover earth sciences and associated safety analyses. Other site-investigation activities are identified but not otherwise considered here. The repositories under consideration are those consisting of mined cavities in deep continental rocks for accepting wastes in the solid and packaged form. The term deep as used in this report is used solely to emphasize the distinction between the repositories discussed in this report and those for shallow-ground disposal. In general, depths under consideration here are greater than 200 metres. The term continental refers to those geological formations that occur either beneath present-day land masses and adjoining islands or beneath the shallow seas. One of the objectives of site investigations is to collect the site-specific data necessary for the different evaluations, such as modelling required to assess the long-term safety of an underground repository

  1. Site investigations for repositories for solid radioactive wastes in deep continental geological formations

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    This report reviews the earth-science investigations and associated scientific studies that may be needed to select a repository site and confirm that its characteristics are such that it will provide a safe confinement for solidified high-level and alpha-bearing and certain other solid radioactive wastes. Site investigations, as used in this report, cover earth sciences and associated safety analyses. Other site-investigation activities are identified but not otherwise considered here. The repositories under consideration are those consisting of mined cavities in deep continental rocks for accepting wastes in the solid and packaged form. The term deep as used in this report is used solely to emphasize the distinction between the repositories discussed in this report and those for shallow-ground disposal. In general, depths under consideration here are greater than 200 metres. The term continental refers to those geological formations that occur either beneath present-day land masses and adjoining islands or beneath the shallow seas. One of the objectives of site investigations is to collect the site-specific data necessary for the different evaluations, such as modelling required to assess the long-term safety of an underground repository.

  2. Study on the development of geological environmental model. 2

    International Nuclear Information System (INIS)

    Tsujimoto, Keiichi; Shinohara, Yoshinori; Saito, Shigeyuki; Ueta, Shinzo; Ohashi, Toyo; Sasaki, Ryouichi; Tomiyama, Shingo

    2003-02-01

    The safety performance assessment was carried out in imaginary geological environment in the conventional research and development of geological disposal, but the importance of safety assessment based on the repository design and scenario considering the concrete geological environment will increase in the future. The research considering the link of the major three fields of geological disposal, investigation of geological environment, repository design, and safety performance assessment, is the contemporary worldwide research theme. Hence it is important to organize information flow that contains the series of information process from the data production to analysis in the three fields, and to systematize the knowledge base that unifies the information flow hierarchically. The information flow for geological environment model generation process is examined and modified base on the product of the research of 'Study on the development of geological environment model' that was examined in 2002. The work flow diagrams for geological structure and hydrology are modified, and those for geochemical and rock property are examined from the scratch. Furthermore, database design was examined to build geoclinal environment database (knowledgebase) based on the results of the systemisation of the environment model generation technology. The geoclinal environment database was designed and the prototype system is build to contribute databased design. (author)

  3. Methodology for the biosphere analysis in the evaluation of deep geological repositories for high radioactive waste

    International Nuclear Information System (INIS)

    Cancio, D.; Pinedo, P.; Aguero, A.; Simon, I.; Torres, C.; Robles, B.; Smith, G.M.; Little, R.; Watkings, B.; Brice, A.; Jaen, J.A.; Coronado, S.

    1997-01-01

    This report summarizes the work done and the achievements reached within the R and D Project that IMA/CIEMAT has had with ENRESA during 1993-1995. The overal R and D Project has a wide radiological protection context, but the work reported here relates only to the development of a Methodology for considering the Biosphere sub-system in the assessments of deep geological repositories for high radioactive wastes (HLW). The main areas concerned within the Methodology have to do with Biosphere structure and morphology in the long-term relevant to deep disposal of HLW: in the contexts of the assessment of these systems, and appropiate modelling of the behaviour of radionuclides released to the biosphere system and with the associated human exposure. This document first provides a review of the past and present international and national concerns about the biosphere modelling and its importance in relation to the definition of safety criteria. A joint ENRESA/ANDRA/IPSN/CIEMAT study about the definition and proactical descriptions of the biosphere systems under different climatic states is then summarized. The Methodology developed by IMA/CIEMAT is outlined with an illustration of the way it works. Different steps and procedures are included for a better proactical understanding of the software tools developed within the project to support the application of the Methologoy. This Methodology is widely based on an international working group on Reference Biospheres part national work for ENRESA has been supported under a collaborative agreement with QuantiSci Ltd. Specific software development have been carried out in collaboration with QuantiSci Ltd and with the Polytechnical University of Madrid. Most of the items included within the Methodology and moreover the Methodology as a whole, follows a continuos progressive development. It is increasinaly recognized that assessment capabilities, establisment of safety criteria and regulatory framework and the steps in a

  4. Progress towards developing an international repository for radioactive waste

    International Nuclear Information System (INIS)

    Kurzeme, M.

    2001-01-01

    Pangea Resources was established to develop and promote the concept of international repositories. The concept was based on repositories located in geologically stable, flat, arid environments meeting the 'high isolation' criteria developed by Pangea Resources. The high isolation concept of Pangea Resources can be applied in various regions of the world, and these have been made public. The pilot project chosen for exploring feasibility was for an international repository in Australia. This study was in preparation for public release, when the existence of the proposal was prematurely revealed to the media. The general media and public reaction to the concept was understandably negative. However, there were also some opinion pieces reported suggesting that the concept of an international repository should be thought about seriously, before it is accepted or rejected. In addition, thoughtful reactions were received from the business and scientific communities. In particular a group of very eminent scientists, the Scientific Review Group, undertook to review independently the quality of the work done. Nevertheless, the reaction from the state and federal governments, was also negative. The Australian Government stated its policy not to permit importation or disposal of foreign nuclear waste. During the last two years Pangea Resources has been developing the technical aspects of the concept and has produced and published several scientific reports on transport, storage and disposal of radioactive materials. All the scientific studies of Pangea Resources have been reviewed by the Scientific Review Group. The work has also been presented in scientific conferences, to the media (including a dedicated television documentary) and to the public. The technical work is generic or is based on diverse potential siting areas around the world and the disposal and storage technologies studied are being broadened beyond the specific high-isolation concept. Most importantly, it has

  5. Use of geo-scientific arguments in the Nirex phased geological repository concept: illustrative desk study

    International Nuclear Information System (INIS)

    Norris, S.; Breen, B.; Knight, L.

    2007-01-01

    A desk study recently undertaken by Nirex used data, collected from now-ceased investigations of the Sellafield site (west Cumbria, UK) undertaken in the 1990's, to consider the implications of locating the Nirex Phased Geological Repository Concept (PGRC) in deep rock formations present at the west Cumbrian coast that contain brines in a slow-moving groundwater flow system. Work undertaken brought together geochemical data and interpretation [1], addressing some questions that were posed during active Sellafield investigations concerning the distribution, composition, origin and age of the brine. The desk study also considered geochemical evidence that has a bearing on understanding the hydrodynamic stability of the brine, noting that it has been investigated in a zone where there are quite sharp changes in physical and chemical groundwater conditions over rather short distances; the simplified hypothesis that this brine is 'very old and virtually immobile' is considered. Other important parts of the scientific framework that provide complementary knowledge and insights were utilised for this desk study; physical hydrogeology and numerical modelling, basinal geology, structure and rock properties, and mineralogy were integrated with geochemistry to develop an understanding of the behaviour of the groundwater system in the study region in terms of its evolution to present day, and its potential future behaviour. Semi-quantitative and qualitative comparison between hydrodynamic and geochemical estimates of water ages are reported. The main assumptions and simplifications in each case that affect the degree of comparability are described in that report, and the consistencies and inconsistencies are discussed and reconciled as far as possible. Geochemical ages for time since recharge of the water in the brine are upwards of 1.6 million years. A probable maximum age of 10 million years is inferred from an assumption about how groundwater history might be coupled to

  6. OPG's deep geologic repository for low and intermediate level waste - recent progress

    International Nuclear Information System (INIS)

    King, F.K.

    2006-01-01

    This paper provides a status report on Canada's first project to build a permanent repository for the long-term management of radioactive waste. Ontario Power Generation has initiated a project to construct a deep geologic repository for low- and intermediate-level waste at the Bruce Nuclear Site, at a depth in the range of 600 to 800 m in an Ordovician-age argillaceous limestone formation. The project is currently undergoing an Environmental Assessment and consulting companies in the areas of environmental assessment, geoscientific site characterization, engineering and safety assessment have been hired and technical studies are underway. Seismic surveys and borehole drilling will be initiated in the fall of 2006. The next major milestone for the project is the submission of the Environmental Assessment report, currently scheduled for December 2008. (author)

  7. Postclosure safety assessment of a deep geological repository for Canada's used nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, N.G.; Kremer, E.P.; Garisto, F.; Gierszewski, P.; Gobien, M.; Medri, C.L.D. [Nuclear Waste Management Organization, Toronto, ON (Canada); Avis, J.D. [Geofirma Engineering Ltd., Ottawa, ON (Canada); Chshyolkova, T.; Kitson, C.I.; Melnyk, W.; Wojciechowski, L.C. [Atomic Energy of Canada Limited, Pinawa, MB (Canada)

    2011-07-01

    This paper reports on elements of a postclosure safety assessment performed for a conceptual design and hypothetical site for a deep geological repository for Canada's used nuclear fuel. Key features are the assumption of a copper used fuel container with a steel inner vessel, container placement in vertical in-floor boreholes, a repository depth of 500 m, and a sparsely fractured crystalline rock geosphere. The study considers a Normal Evolution Scenario together with a series of Disruptive Event Scenarios. The Normal Evolution Scenario is a reasonable extrapolation of present day site features and receptor lifestyles, while the Disruptive Event Scenarios examine abnormal and unlikely failures of the containment and isolation systems. Both deterministic and probabilistic simulations were performed. The results show the peak dose consequences occur far in the future and are well below the applicable regulatory acceptance criteria and the natural background levels. (author)

  8. Proposal for geological site selection for L/ILW and HLW repositories. Statement of requirements, procedure and results. Technical report 08-03

    International Nuclear Information System (INIS)

    2008-10-01

    Important steps in the process of managing radioactive wastes have already been implemented in Switzerland. These include the handing and packaging of the waste, waste characterisation and documentation of waste inventories and interim storage along with associated transport. In terms of preparing for deep geological disposal, the necessary scientific and technical work is well advanced and the feasibility of constructing geological repositories that provide the required long-term safety has been successfully demonstrated for all waste types arising in Switzerland. Sufficient knowledge is available to allow the next steps in the selection of repository sites to be defined. The legal framework is also in place and organisational measures have been provided that will allow the tasks to be performed in the coming years to be implemented efficiently. The selection of geological siting regions and sites for repositories in Switzerland will be conducted in three stages. Stage 1 ends with the definition of geological siting regions within which the repository projects will be elaborated in more detail in stages 2 and 3. This report documents and justifies the siting proposals prepared by Nagra for the repositories for low- and intermediate-level waste (L/ILW) and high-level waste (HLW). Formulation of these proposals is conducted in five steps: 1) The waste inventory, which includes reserves for future developments, is allocated to the L/ILW and HLW repositories; 2) Based on this waste allocation, the second step involves defining the barrier and safety concepts for the two repositories. With a view to evaluating the geological siting possibilities, quantitative and qualitative guidelines and requirements on the geology are derived on the basis of these concepts. These relate to the time period to be considered, the space requirements for the repository, the properties of the host rock (depth, thickness, lateral extent, hydraulic conductivity), long-term stability

  9. Nuclear Waste Facing the Test of Time: The Case of the French Deep Geological Repository Project.

    Science.gov (United States)

    Poirot-Delpech, Sophie; Raineau, Laurence

    2016-12-01

    The purpose of this article is to consider the socio-anthropological issues raised by the deep geological repository project for high-level, long-lived nuclear waste. It is based on fieldwork at a candidate site for a deep storage project in eastern France, where an underground laboratory has been studying the feasibility of the project since 1999. A project of this nature, based on the possibility of very long containment (hundreds of thousands of years, if not longer), involves a singular form of time. By linking project performance to geology's very long timescale, the project attempts "jump" in time, focusing on a far distant future, without understanding it in terms of generations. But these future generations remain measurements of time on the surface, where the issue of remembering or forgetting the repository comes to the fore. The nuclear waste geological storage project raises questions that neither politicians nor scientists, nor civil society, have ever confronted before. This project attempts to address a problem that exists on a very long timescale, which involves our responsibility toward generations in the far future.

  10. 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)

  11. Geological criteria for site selection of an LILW radioactive waste repository in the Philippines

    International Nuclear Information System (INIS)

    Aurelio, Mario; Taguibao, Kristine Joy; Vargas, Edmundo; Palattao, Maria Visitacion; Reyes, Rolando; Nohay, Carl; Singayan, Alfonso

    2013-01-01

    In the selection of sites for disposal facilities involving low- and intermediate-level radioactive waste (LILW), International Atomic Energy Agency (IAEA) recommendations require that 'the region in which the site is located shall be such that significant tectonic and surface processes are not expected to occur with an intensity that would compromise the required isolation capability of the repository'. Evaluating the appropriateness of a site therefore requires a deep understanding of the geological and tectonic setting of the area. The Philippines sits in a tectonically active region frequented by earthquakes and volcanic activity. Its highly variable morphology coupled with its location along the typhoon corridor in the west Pacific region subjects the country to surface processes often manifested in the form of landslides. The Philippine LILW near surface repository project site is located on the north eastern sector of the Island of Luzon in northern Philippines. This island is surrounded by active subduction trenches; to the east by the East Luzon Trough and to the west by the Manila Trench. The island is also traversed by several branches of the Philippine Fault System. The Philippine LILW repository project is located more than 100 km away from any of these major active fault systems. In the near field, the project site is located less than 10 km from a minor fault (Dummon River Fault) and more than 40 km away from a volcanic edifice (Mt. Caguas). This paper presents an analysis of the potential hazards that these active tectonic features may pose to the project site. The assessment of such geologic hazards is imperative in the characterization of the site and a crucial input in the design and safety assessment of the repository. (authors)

  12. Siting of repositories for high level nuclear waste geological and institutional issues

    International Nuclear Information System (INIS)

    Ahagen, H.

    1993-01-01

    Two studies have been conducted in Sweden under contract from SKN-National Board for Spent Nuclear Fuel. The responsibilities of SKN has been transferred to SKI as of July 1, 1992. The first study is related to a compilation of experience and lessons learned from siting of nuclear waste repositories and other controversial facilities in seven countries. The second study is aimed at compiling examples of the state of knowledge related to the regional geological information with relevance to siting of a repository in Sweden. This paper is drawing the general combined conclusions from both these studies. The first study reviewed programs for siting of nuclear and hazardous waste disposal facilities in Canada, Finland, France, Sweden, Switzerland, United Kingdom and USA. The main topics reviewed are related to a/ The use of technical screening, b/ Legal framework and local veto, c/ Public involvement, d/ Interim storage and schedule flexibility, e/ Sequential vs. parallel characterization. The second study focused on the regional geological information available for Sweden and if this information allows for a ''grouping'' of tectonic regions in Sweden with significant differences in history and characteristics. Factors studied as potentially important for siting are bedrock properties, mineralizations, ground water conditions and available volume for a repository. The experience gained from these studies is aimed to be used as background information in the review of the program conducted for the Swedish nuclear utilities by SKB. SKB will according to current plans initiate siting for a repository for spent nuclear fuel in Sweden during 1993. (author). 2 refs

  13. Geological criteria for site selection of an LILW radioactive waste repository in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Aurelio, Mario; Taguibao, Kristine Joy [National Institute of Geological Sciences, University of the Philippines, Quezon City (Philippines); Vargas, Edmundo; Palattao, Maria Visitacion; Reyes, Rolando; Nohay, Carl; Singayan, Alfonso [Philippine Nuclear Research Institute, Department of Science and Technology, Quezon City (Philippines)

    2013-07-01

    In the selection of sites for disposal facilities involving low- and intermediate-level radioactive waste (LILW), International Atomic Energy Agency (IAEA) recommendations require that 'the region in which the site is located shall be such that significant tectonic and surface processes are not expected to occur with an intensity that would compromise the required isolation capability of the repository'. Evaluating the appropriateness of a site therefore requires a deep understanding of the geological and tectonic setting of the area. The Philippines sits in a tectonically active region frequented by earthquakes and volcanic activity. Its highly variable morphology coupled with its location along the typhoon corridor in the west Pacific region subjects the country to surface processes often manifested in the form of landslides. The Philippine LILW near surface repository project site is located on the north eastern sector of the Island of Luzon in northern Philippines. This island is surrounded by active subduction trenches; to the east by the East Luzon Trough and to the west by the Manila Trench. The island is also traversed by several branches of the Philippine Fault System. The Philippine LILW repository project is located more than 100 km away from any of these major active fault systems. In the near field, the project site is located less than 10 km from a minor fault (Dummon River Fault) and more than 40 km away from a volcanic edifice (Mt. Caguas). This paper presents an analysis of the potential hazards that these active tectonic features may pose to the project site. The assessment of such geologic hazards is imperative in the characterization of the site and a crucial input in the design and safety assessment of the repository. (authors)

  14. Secure and Reliable Wireless Communications for Geological Repositories and Nuclear Facilities

    International Nuclear Information System (INIS)

    Twogood, R.

    2015-01-01

    There is an important need to develop new generation robust RF communication systems to support wireless communications and instrumentation control in geological repositories and nuclear facilities, such as nuclear power plants. Often these facilities have large metallic structures with electromagnetic (EM) transients from plant equipment. The ambient EMI/RFI harsh environment is responsible for degrading radio link bandwidth. Current communication systems often employ physical cables that are not only expensive to install, but deteriorate over time and are vulnerable to failures. Furthermore, conventional high-power narrowband walkie-talkies sometimes upset other electronics. On the other hand, high-quality reliable wireless communications between operators and automated control systems are critical in these facilities, as wireless sensors become more and more prevalent in these operations. In an effort to develop novel wireless communications systems, Dirac Solutions Inc. (DSI) in collaboration with Lawrence Livermore National Laboratory (LLNL), has developed high-quality ultra-wideband (UWB) hand-held communications systems that have proven to have excellent performance in ships and tunnels. The short pulse UWB RF technology, with bandwidths of many hundreds of MHz's, are non-interfering due to low average power. Furthermore, the UWB link has been shown to be highly reliable in the presence of other interfering signals. The DSI UWB communications systems can be adapted for applications in tunnels and nuclear power facilities for voice, data, and instrumentation control. In this paper we show examples of voice communication in ships with UWB walkie-talkies. We have developed novel modulation and demodulation techniques for short pulse UWB communications. The design is a low-power one and in a compact form. The communication units can be produced inexpensively in large quantities. A major application of these units might be their use by IAEA inspectors and

  15. Efficiency analyses of the CANDU spent fuel repository using modified disposal canisters for a deep geological disposal system design

    International Nuclear Information System (INIS)

    Lee, J.Y.; Cho, D.K.; Lee, M.S.; Kook, D.H.; Choi, H.J.; Choi, J.W.; Wang, L.M.

    2012-01-01

    Highlights: ► A reference disposal concept for spent nuclear fuels in Korea has been reviewed. ► To enhance the disposal efficiency, alternative disposal concepts were developed. ► Thermal analyses for alternative disposal concepts were performed. ► From the result of the analyses, the disposal efficiency of the concepts was reviewed. ► The most effective concept was suggested. - Abstract: Deep geological disposal concept is considered to be the most preferable for isolating high-level radioactive waste (HLW), including nuclear spent fuels, from the biosphere in a safe manner. The purpose of deep geological disposal of HLW is to isolate radioactive waste and to inhibit its release of for a long time, so that its toxicity does not affect the human beings and the biosphere. One of the most important requirements of HLW repository design for a deep geological disposal system is to keep the buffer temperature below 100 °C in order to maintain the integrity of the engineered barrier system. In this study, a reference disposal concept for spent nuclear fuels in Korea has been reviewed, and based on this concept, efficient alternative concepts that consider modified CANDU spent fuels disposal canister, were developed. To meet the thermal requirement of the disposal system, the spacing of the disposal tunnels and that of the disposal pits for each alternative concept, were drawn following heat transfer analyses. From the result of the thermal analyses, the disposal efficiency of the alternative concepts was reviewed and the most effective concept suggested. The results of these analyses can be used for a deep geological repository design and detailed analyses, based on exact site characteristics data, will reduce the uncertainty of the results.

  16. AEGIS technology demonstration for a nuclear waste repository in basalt. Assessment of effectiveness of geologic isolation systems

    International Nuclear Information System (INIS)

    Dove, F.H.; Cole, C.R.; Foley, M.G.

    1982-09-01

    A technology demonstration of current performance assessment techniques as applied to a nuclear waste repository in the Columbia Plateau Basalts was conducted. Hypothetical repository coordinates were selected for an actual geographical setting on the Hanford Reservation in the state of Washington. Published hydrologic and geologic data used in the analyses were gathered in 1979 or earlier. The following report documents the technology demonstration in basalt. Available information has been used to establish the data base and initial hydrologic and geologic interpretations for this site-specific application. A simplified diagram of the AEGIS analyses is shown. Because an understanding of the dynamics of ground-water flow is essential to the development of release scenarios and consequence analyses, a key step in the demonstration is the systems characterization contained in the conceptual model. Regional and local ground-water movement patterns have been defined with the aid of hydrologic computer models. Hypothetical release scenarios have been developed and evaluated by a process involving expert opinion and a Geologic Simulation Model for basalt. (The Geologic Simulation Model can also be used to forecast future boundary conditions for the hydrologic simulation.) Chemical reactivity of the basalt with ground water will influence the leaching and transport of radionuclides; solubility equilibria based on available data are estimated with geochemical models. After the radionuclide concentrations are mathematically introduced into the ground-water movement patterns, waste movement patterns are outlined over elapsed time. Contaminant transport results are summarized for significant radionuclides that are hypothetically released to the accessible environment and to the biosphere

  17. AEGIS technology demonstration for a nuclear waste repository in basalt. Assessment of effectiveness of geologic isolation systems

    Energy Technology Data Exchange (ETDEWEB)

    Dove, F.H.; Cole, C.R.; Foley, M.G.

    1982-09-01

    A technology demonstration of current performance assessment techniques as applied to a nuclear waste repository in the Columbia Plateau Basalts was conducted. Hypothetical repository coordinates were selected for an actual geographical setting on the Hanford Reservation in the state of Washington. Published hydrologic and geologic data used in the analyses were gathered in 1979 or earlier. The following report documents the technology demonstration in basalt. Available information has been used to establish the data base and initial hydrologic and geologic interpretations for this site-specific application. A simplified diagram of the AEGIS analyses is shown. Because an understanding of the dynamics of ground-water flow is essential to the development of release scenarios and consequence analyses, a key step in the demonstration is the systems characterization contained in the conceptual model. Regional and local ground-water movement patterns have been defined with the aid of hydrologic computer models. Hypothetical release scenarios have been developed and evaluated by a process involving expert opinion and a Geologic Simulation Model for basalt. (The Geologic Simulation Model can also be used to forecast future boundary conditions for the hydrologic simulation.) Chemical reactivity of the basalt with ground water will influence the leaching and transport of radionuclides; solubility equilibria based on available data are estimated with geochemical models. After the radionuclide concentrations are mathematically introduced into the ground-water movement patterns, waste movement patterns are outlined over elapsed time. Contaminant transport results are summarized for significant radionuclides that are hypothetically released to the accessible environment and to the biosphere.

  18. Generic description of facilities at the shaft head (auxiliary entrance installations) of deep geological repositories

    International Nuclear Information System (INIS)

    2016-10-01

    In a deep geological repository, the access structures function as the link between the surface and the installations and structures at the disposal level. In the planned implementation scenarios, at least two access structures will be in operation up to the time of closure of the repository. The radioactive waste will be transported via the main access from the surface to the disposal level during emplacement operations. For the construction and operation of a deep geological repository, additional access structures are required. These auxiliary accesses and the associated surface infrastructure (e.g. shaft head installations) form the subject of this report. To provide as broad and comprehensive a description as possible, seven types of auxiliary access facilities are defined; these are characterised in line with the current status of planning and their functions and impacts are described. During construction, operation and dismantling of auxiliary access facilities, the usual conventional safety measures (inter alia) have to be observed (e.g. groundwater protection, fire prevention, facility security, accident prevention). Regarding the 'Ordinance on Protection against Major Accidents' no large quantities of hazardous materials, i.e. above the corresponding threshold quantities, are to be expected in the auxiliary access facilities. Proper handling and compliance with applicable regulations in all phases will ensure no hazard to humans and the environment. As no handling of radioactive materials is foreseen in the auxiliary access facilities, and because exhaust air and waste water from the controlled zones of a repository will, in principle, be removed via the main access and not the auxiliary accesses, a safety-relevant emission of radioactive substances and transport of contaminated material can be ruled out for the auxiliary access facilities during both normal operation and also in the case of an accident. Based on the information presented in

  19. 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

  20. Canada's deep geological repository for used nuclear fuel - site selection process update

    International Nuclear Information System (INIS)

    Facella, J.

    2014-01-01

    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 in a deep geological repository, located in an informed and willing host. The process of site selection is an important milestone in this program. The NWMO describes its approach to working collaboratively with communities which expressed interest in exploring the project, as well as Aboriginal communities in the area and other surrounding communities. The project is designed to be implemented through a long-term partnership involving the interested community, Aboriginal communities and surrounding communities working with the NWMO. (author)

  1. Annular air space effects on nuclear waste canister temperatures in a deep geologic waste repository

    International Nuclear Information System (INIS)

    Lowry, W.E.; Cheung, H.; Davis, B.W.

    1980-01-01

    Air spaces in a deep geologic repository for nuclear high level waste will have an important effect on the long-term performance of the waste package. The important temperature effects of an annular air gap surrounding a high level waste canister are determined through 3-D numerical modeling. Air gap properties and parameters specifically analyzed and presented are the air gap size, surfaces emissivity, presence of a sleeve, and initial thermal power generation rate; particular emphasis was placed on determining the effect of these variables have on the canister surface temperature. Finally a discussion based on modeling results is presented which specifically relates the results to NRC regulatory considerations

  2. Status of technology for isolating high-level radioactive wastes in geologic repositories

    International Nuclear Information System (INIS)

    Klingsberg, C.; Duguid, J.

    1980-10-01

    This report attempts to summarize the status of scientific and technological knowledge relevant to long-term isolation of high-level and transuranic wastes in a mined geologic repository. It also identifies and evaluates needed information and identifies topics in which work is under way or needed to reduce uncertainties. The major findings and conclusions on the following topics are presented: importance of the systems approach; prospects for successful isolation of wastes; need for site-specific investigations; human activities in the future; importance of modelling; disposal of transuranic wastes; status of technology of isolation barriers, performance assessment, site selection and characterization, and potential host rocks

  3. Geological mappability of bored versus drill and blast excavations for radioactive waste repositories

    International Nuclear Information System (INIS)

    Nilsen, B.; Ozdemir, L.

    1992-01-01

    The issue of accurate geological mappability has been subject of intense debate in the selection of bored versus drill and blast excavation for radioactive waste repositories. This paper is intended to provide an assessment of the problems usually encountered in mappability on the basis of field experience from a large number of completed tunnels, mainly as part of the Norwegian hydropower projects. The main conclusion is that mapping in a mechanically excavated underground opening, with very few exceptions, reflects the in-situ conditions more accurately than mapping in a drill and blast tunnel. This is due to the overbreak effects of drill and blast excavation, primarily

  4. Mining and engineering aspects and variants for the underground construction of a deep geological repository for radioactive waste and spent nuclear fuel

    International Nuclear Information System (INIS)

    Milchev, M.; Michailov, B.; Nanovska, E.; Harizanov, A.

    2003-01-01

    The aim of the present report is to investigate and to describe systematically the foreign experience, scientific and technical achievements and stages of development concerning the mining and engineering aspects and variants for underground construction of a deep geological repository for radioactive waste (RAW) and spent nuclear fuel (SNF). The ideal solution in managing the problems with harmful wastes seems to be either to remove them permanently from Earth (which is related with high risks and high costs) or to transform long-lived radionuclides to short-lived radionuclides using nuclear transmutation processes in a reactor or a particle accelerator. The latter is also a complex and immensely costly process and it can only reduce the quantities of some long-lived radionuclides, which can be then disposed in a geological repository. At present, the deep geological disposal remains the only solution for solving the problem with the hazard of storing radioactive wastes. The report submits a brief description and systematization of the performed investigations, accompanied by analysis of the scientific and technical level on world scale. The analysis is related with the particular geological conditions and the existing scientific studies available so far in Bulgaria. The main conclusions are that the complex scientific-technical and engineering problems related with the construction of a deep geological repository for RAW and SNF require long-term scientific investigations and preliminary complex works and it is high time to launch them in Bulgaria. (authors)

  5. Towards Content Development For Institutional Digital Repository ...

    African Journals Online (AJOL)

    The growth in Information and Communication Technology has lead to the emergence of Institutional Digital Repository, a digital archive for the preservation and dissemination of institutional research outputs. Institutional Digital Repositories make possible global dissemination of research outputs through the use of the ...

  6. 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

  7. The use of laboratory adsorption data and models to predict radionuclide releases from a geological repository: A brief history

    International Nuclear Information System (INIS)

    Langmuir, D.

    1997-01-01

    Radionuclide (RN) adsorption has long been recognized as important to assure the isolation of nuclear wastes in a geological repository. Laboratory measured RN adsorption data have generally been expressed as distribution coefficient (K d ) values or adsorption isotherms. The surface complexation (SC) adsorption models were introduced in the late 1970''s. The best known of these models incorporate electrical double layer (EDL) theory. Their use requires that the water chemistry and surface properties of adsorbing rocks and minerals be fully characterized. Because the SC models are relatively mechanistic, they may allow extrapolation of adsorption results to repository conditions that lie outside the limited experimental range used to parameterize a given model. Turner has shown that the diffuse layer model (the simplest SC model) fits a wide range of RN adsorption data as well as the more complex models. Others have suggested ways to generalize and estimate SC model parameters for a variety of minerals, rocks and engineered materials. Degueldre and Werlni and Degueldre et al. have proposed a simplified SC model for RN adsorption that avoids EDL theory, in which the adsorption of RN species is estimated from linear free energy relationships. It is appropriate to ask how accurately RN adsorption behavior must be known or understood for total system performance analysis (TSPA). In most geological settings now being considered for repository development globally, it may suffice to select bounding K d values for the different rock types. Use of the SC models to describe RN adsorption can provide one with increased confidence that minimum K d ''s and the distribution of K d values the author might propose for TSPA are in fact conservative. 68 refs., 5 figs., 1 tab

  8. Operational procedures for receiving, packaging, emplacing, and retrieving high-level and transuranic waste in a geologic repository in TUFF

    International Nuclear Information System (INIS)

    Dennis, A.W.; Mulkin, R.

    1984-01-01

    The Nevada Nuclear Waste Storage Investigations Project, directed by the Nevada Operations Office of the Department of Energy, is currently developing conceptual designs for a commercial nuclear waste repository. In this paper, the preliminary repository operating plans are identified and the proposed repository waste inventory is discussed. The receipt rates for truck and rail car shipments of waste are determined as are the required repository waste emplacement rates

  9. Canada's Deep Geological Repository for Used Nuclear Fuel - Geo-scientific Site Evaluation Process - 13117

    International Nuclear Information System (INIS)

    Blyth, Alec; Ben Belfadhel, Mahrez; Hirschorn, Sarah; Hamilton, Duncan; McKelvie, Jennifer

    2013-01-01

    The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management (APM), the approach selected by the Government of Canada for long-term management of used nuclear fuel generated by Canadian nuclear reactors. The ultimate objective of APM is the centralized containment and isolation of Canada's used nuclear fuel in a Deep Geological Repository in a suitable rock formation at a depth of approximately 500 meters (m) (1,640 feet [ft]). In May 2010, the NWMO published a nine-step site selection process that serves as the road map to decision-making on the location for the deep geological repository. The safety and appropriateness of any potential site will be assessed against a number of factors, both technical and social in nature. The selected site will be one that can be demonstrated to be able to safely contain and isolate used nuclear fuel, protecting humans and the environment over the very long term. The geo-scientific suitability of potential candidate sites will be assessed in a stepwise manner following a progressive and thorough site evaluation process that addresses a series of geo-scientific factors revolving around five safety functions. The geo-scientific site evaluation process includes: Initial Screenings; Preliminary Assessments; and Detailed Site Evaluations. As of November 2012, 22 communities have entered the site selection process (three in northern Saskatchewan and 18 in northwestern and southwestern Ontario). (authors)

  10. Deep geological repositories. Safe operation and long-term safety in the prism of reversibility

    Energy Technology Data Exchange (ETDEWEB)

    Espivent, Camille; Tichauer, Michael [IRSN, Fontenay-aux-Roses (France)

    2015-07-01

    A deep geological repository is the reference solution enshrined in the French law for the long-term management of high-level radioactive waste. The current project is led by Andra, the French radioactive waste management organization. As a technical support organization, IRSN's mission is, on the basis of the safety case produced by Andra, to assess the safety of such a facility at its various stages of development, that is to say the design, construction, operation and post-closure phases of the facility. Such a facility will have to meet specific requirements, within different time frames as stated above. One of the requirements is ''reversibility'': in fact, French law poses that the geological disposal will have to be ''reversible'' for a certain time, yet not fully defined. Reversibility is nevertheless believed encompassing both the decision making process related to the waste emplacement process during operational phase and the ability to retrieve waste, should such a decision be made. Thus, underground structures have to be designed and operated to allow both waste emplacement and removal. Moreover, future decision making about the disposal process will have to rely on a sound technical basis. This implies a data collection scheme and a monitoring program of the facility to check if the disposal process is bound by limits, controls and conditions compatible with (i) a safe operation of the facility and (ii) the state of the facility that the operator wants to achieve at the time of its closure, so that long-term safety is guaranteed. Therefore, technical criteria and key parameters have to be selected and monitored during construction and operation, that is to say for decades. Then, reversibility have to make room for corrective actions, including the retrieval of waste, if something goes wrong and especially if the facility is not seen as safe anymore, especially in the perspective of long-term safety. To

  11. Deep geological repositories. Safe operation and long-term safety in the prism of reversibility

    International Nuclear Information System (INIS)

    Espivent, Camille; Tichauer, Michael

    2015-01-01

    A deep geological repository is the reference solution enshrined in the French law for the long-term management of high-level radioactive waste. The current project is led by Andra, the French radioactive waste management organization. As a technical support organization, IRSN's mission is, on the basis of the safety case produced by Andra, to assess the safety of such a facility at its various stages of development, that is to say the design, construction, operation and post-closure phases of the facility. Such a facility will have to meet specific requirements, within different time frames as stated above. One of the requirements is ''reversibility'': in fact, French law poses that the geological disposal will have to be ''reversible'' for a certain time, yet not fully defined. Reversibility is nevertheless believed encompassing both the decision making process related to the waste emplacement process during operational phase and the ability to retrieve waste, should such a decision be made. Thus, underground structures have to be designed and operated to allow both waste emplacement and removal. Moreover, future decision making about the disposal process will have to rely on a sound technical basis. This implies a data collection scheme and a monitoring program of the facility to check if the disposal process is bound by limits, controls and conditions compatible with (i) a safe operation of the facility and (ii) the state of the facility that the operator wants to achieve at the time of its closure, so that long-term safety is guaranteed. Therefore, technical criteria and key parameters have to be selected and monitored during construction and operation, that is to say for decades. Then, reversibility have to make room for corrective actions, including the retrieval of waste, if something goes wrong and especially if the facility is not seen as safe anymore, especially in the perspective of long-term safety. To

  12. 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

  13. Archive of Geosample Data and Information from the Oregon State University (OSU) College of Earth, Ocean and Atmospheric Sciences (CEOAS) Marine Geology Repository (MGR)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Oregon State University Marine Geology Repository (OSU-MGR) is a partner in the Index to Marine and Lacustrine Geological Samples (IMLGS) database, contributing...

  14. Ontario Power Generation's proposed L and ILW deep geologic repository: geo-scientific assessment

    International Nuclear Information System (INIS)

    Jensen, Mark; Raven, Ken; Leech, Robert

    2012-01-01

    repository safety. Site specific investigations of the Bruce nuclear site began in the fall of 2006 and were completed by summer 2010 (INTERA, 2011; NWMO, 2011). Planning activities leading to the execution of the site-specific investigations were guided, in part, by a conceptual understanding of the geologic and hydrologic settings, and the development of seven hypotheses, which addressed issues such as long-term groundwater system behaviour, natural resource potential, geomechanical stability, seismic hazard and protection of ground and surface water resources (INTERA 2006; INTERA 2008). The intent of the later was to focus data collection and improve the integration of data sets to test and confirm the initial conceptual model. The investigations were conducted in three phases or campaigns and have involved among other studies, the drilling, coring and instrumentation of 6 deep (4 vertical; 2 inclined) boreholes through the sedimentary sequence coupled with in-situ and laboratory testing (INTERA 2011). Results provide a unique data set that describes a groundwater system comprised of multiple near-horizontally layered aquitards-aquicludes [thick ( -13 m sec -1 ), low porosity (0.01-0.08), saline (TDS ≥ 250 gm l -1 ), low effective diffusion coefficient (10 -12 m 2 sec -1 )] in which multiple lines of evidence point to a deep-seated diffusion-dominant transport regime. The Geo-synthesis examines the geologic setting from a broader geo-scientific context in order to present an integrated assessment of the Bruce nuclear site (NWMO, 2011). In addition to the site-specific data, the Geo-synthesis is supported by 14 supplemental studies, which assess, for example, glacial ice-sheet history, site and regional-scale paleo-hydrogeology, geomechanical stability of un-backfilled DGR openings, aquiclude pore fluid diagenesis/origin, long-term DGR shaft seal integrity, karstification, neo-tectonics, seismic hazard and Ordovician shale cap rock barrier integrity. This paper provides

  15. Process mining software repositories: do developers work as expected?

    NARCIS (Netherlands)

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

    2012-01-01

    Modern software development commonly makes use of a multitude of software repositories. How can these help us to understand the on-going development process? Researchers of Eindhoven University of Technology design new methods revealing how software has been developed.

  16. Development of the SIOPE DIPG network, registry and imaging repository

    DEFF Research Database (Denmark)

    Veldhuijzen van Zanten, Sophie E M; Baugh, Joshua; Chaney, Brooklyn

    2017-01-01

    was developed, The SIOPE DIPG Registry and Imaging Repository, to centrally collect data of DIPG patients. As for April 2016, clinical data as well as MR-scans of 694 patients have been entered into the SIOPE DIPG Registry/Imaging Repository. The median progression free survival is 6.0 months (95% Confidence...

  17. 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

  18. Archive of Geosample Data and Information from the U.S. Geological Survey (USGS) Coastal and Marine Geology Program (CMGP) Woods Hole Coastal and Marine Science Center (WHCMSC) Samples Repository

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The U.S. Geological Survey Coastal and Marine Geology Program (CMGP) Woods Hole Coastal and Marine Science Center (WHCMSC) Samples Repository is a partner in the...

  19. Archive of Geosample Data and Information from the U.S. Geological Survey (USGS) Coastal and Marine Geology Program (CMGP) St. Petersburg Coastal and Marine Science Center (SPCMSC) Samples Repository

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The U.S. Geological Survey Coastal and Marine Geology Program (CMGP) St. Petersburg Coastal and Marine Science Center (SPCMSC) Samples Repository is a partner in the...

  20. Archive of Geosample Data and Information from the U.S. Geological Survey (USGS) Coastal and Marine Geology Program (CMGP) Pacific Coastal and Marine Science Center (PCMSC) Samples Repository

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The U.S. Geological Survey Coastal and Marine Geology Program (CMGP) Pacific Coastal and Marine Science Center (PCMSC) Samples Repository is a partner in the Index...

  1. Corrosion of high purity copper as engineering barrier in deep geological repositories

    International Nuclear Information System (INIS)

    Ochoa, Maité; Rodríguez Martín, A.; Farina Silvia, B.

    2013-01-01

    Pure copper with oxygen content below 5 ppm (to minimize segregation at grain boundaries) and doped with phosphorus (to increase creep resistance) is the chosen material for the corrosion-resistant barrier of the High Level Radioactive 2 Wastecontainers in the Swedish and Finnish repository models. These models include the construction of the repository below the water table, which is a reducing environment in which copper has excellent resistance to general and localized corrosion in aqueous electrolytes. The aim of this work is contribute to determine the durability of the material, given that deep geological repositories of HLW are designed to ensure the protection of the environment for periods of hundreds of thousands years. As a first step in a more general analysis the effects of chloride, one of the main aggressive species of corrosion, are evaluated. To this purpose corrosion potential was determined and anodic polarization curves were performed in deaerated solutions varying the chloride concentration between 0.01 and 1M and the temperature between 30 and 90°C. Several electrochemical techniques were used: the evolution of corrosion potential was measured, anodic polarization curves were obtained and electrochemical impedance tests were performed. The analysis was complemented with microscopic observations of the type of corrosive attack, as well as determinations of the eventual corrosion products formed using Energy-Dispersive X-ray Analysis (EDS). Results show that the corrosion potential decreases with the increase of temperature and with the increase of chloride concentration. A correlation of the corrosion potential as a function of temperature and chloride concentration was obtained, with the purpose of making predictions in variable conditions.The current density increases both with temperature and with chloride concentration. A pitting potential is observed in certain conditions. (author)

  2. NRC regulations for disposal of high-level radioactive wastes in geologic repositories: technical criteria

    International Nuclear Information System (INIS)

    Martin, J.B.; Bell, M.J.; Regnier, E.P.

    1983-01-01

    The Nuclear Regulatory Commission is promulgating regulations specifying the technical criteria fo disposal of high-level radioactive wastes in geologic repositories. The proposed rule was published for public comment in July 1981. Public comments have been received and considered by the Commission staff. The Commission will soon approve and publish a revised final rule. While the final rule being considered by the Commission is fundamentally the same as the proposed rule, provisions have been added to permit flexibility in the application of numerical criteria, some detailed design requirements have been deleted, and other changes have been made in response to comments. The rule is consistent with the recently enacted Nuclear Waste Policy Act of 1982

  3. Canada's deep geological repository for used nuclear fuel - the geoscientific site evaluation process

    Energy Technology Data Exchange (ETDEWEB)

    Belfadhel, M.B.; Blyth, A.; Desroches, A.; Hirschorn, S.; Mckelvie, J.; Sanchez-Rico Castejon, M.; Parmenter, A.; Urrutia-Bustos, A.; Vorauer, A., E-mail: mbenbelfadhel@nwmo.ca [Nuclear Waste Management Organization, Toronto, ON (Canada)

    2014-07-01

    The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management (APM), the approach selected by the Government of Canada for the long-term management of used nuclear fuel generated by Canadian nuclear reactors. The ultimate objective of APM 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. In May 2010, the NWMO initiated a nine-step site selection process to find an informed and willing community to host the project. This paper describes the approach, methods and criteria being used to assess the geoscientific suitability of communities currently involved in the site selection process. The social, cultural and economic aspects of the assessment are discussed in a companion paper. (author)

  4. 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

  5. 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

  6. Evaluation of radionuclide migration in the homogeneous system of a geological repository

    International Nuclear Information System (INIS)

    Prvakova, S.; Duran, J.; Necas, V.

    2005-01-01

    The aim of this paper is to study radionuclide migration and release from a deep underground repository situated in a clay formation. An insight into the processes influencing the radionuclide transport in the near field and far field will be presented. For the calculation, a set of radionuclides has been chosen, considering the half-life, decay chains, capacity of the sorption, solubility limits and diffusion coefficients. The migration of radionuclides is dependent on transport properties of the particular nuclide. Due to the low hydraulic conductivity of the backfill material and clay geological formation, the transport in the repository occurs mainly by diffusion. The migration rate will be influenced by the water chemistry, solubility, retardation and diffusive properties of the nuclides, and the water flow rate in the clay. The release rates of radionuclides from the geosphere to the biosphere will be converted into the indicative dose rates using dose conversion factors for ingestion. The impact of the critical group is considered via consumption of meat, root vegetables and drinking water from wells. (author)

  7. Preclosure Seismic Design Methodology for a Geologic Repository at Yucca Mountain

    International Nuclear Information System (INIS)

    K. Coppersmith

    2004-01-01

    This topical report describes the methodology and criteria that the U.S. Department of Energy (DOE) intends to use for preclosure seismic design of structures, systems, and components (SSCs) that are important to safety (ITS) in the geologic repository operations area. 10 Code of Federal Regulations (CFR) Part 63 [DIRS 156605], states that for a license to be issued for operation of a high-level radioactive waste repository, the U.S. Nuclear Regulatory Commission (NRC) must find that the facility will not constitute an unreasonable risk to the health and safety of the public (Section 63.41[c] [DIRS 156605]). Section 63.21(c)(5) [DIRS 156605] requires that a preclosure safety analysis (PCSA) be performed to ensure that the preclosure performance objectives (Section 63.111 [DIRS 156605]) have been met. The PCSA is a systematic examination of the site, the design, and the potential hazards (Section 63.102[f] [DIRS 156605]), including a comprehensive identification of potential event sequences. Potential naturally-occurring hazards include those event sequences that are initiated by earthquake ground motions or fault displacements due to earthquakes

  8. A method of identifying social structures in siting regions for deep geological repositories in Switzerland

    International Nuclear Information System (INIS)

    Brander, Simone

    2010-09-01

    Acceptance is a key element in the site selection process for deep geological repositories for high-level and low and intermediate-level radioactive waste in Switzerland. Participation requirements such as comprehensive negotiation issues and adequate resources have thus been defined by the Swiss Federal Office of Energy (SFOE). In 2008, on the basis of technical criteria Nagra (National Cooperative for the Disposal of Radioactive Waste) proposed several potential areas for deep geological repositories. The number of potential areas will be narrowed down within the next few years. All municipalities within the planning perimeter (the area in which surface facilities can be realised) are affected and form the siting region. In order to ensure that the local population have their say in the forthcoming discussions, regional participation bodies including all municipalities within a siting region are being set up by the SFOE. Regional participation ensures that local interests, needs and values are taken into account in the site selection process. Assembling the regional participation bodies is therefore of great importance. Before such bodies can be formed, however, the various interests, needs and values have to be identified, and special attention has to be paid to long-term interests of future generations, as well as to non-organised and under-represented interests. According to the concept of proportional representation, the interests, needs and values that are identified and weighted by the local population are to be represented in the regional participation procedure. The aim of this study is to share a method of mapping existing social structures in a defined geographical area. This involves a combination of an analysis of socio-economic statistical data and qualitative and quantitative social research methods

  9. Dynamic use of geoscience information to develop scientific understanding for a nuclear waste repository

    International Nuclear Information System (INIS)

    Cook, N.G.W.; Tsang, C.F.

    1990-01-01

    This paper discusses the development and safety evaluation of a nuclear waste geologic repository. Scientific understanding dependent upon information from a number of geoscience disciplines is described. A discussion is given on the dynamic use of the information through the different stages. The authors point out the need for abstracting, deriving and updating a quantitative spatial and process model (QSPM) to develop a scientific understanding of site responses as a crucial element in the dynamic procedure

  10. 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)

  11. Multi-dimensional transport modelling of corrosive agents through a bentonite buffer in a Canadian deep geological repository.

    Science.gov (United States)

    Briggs, Scott; McKelvie, Jennifer; Sleep, Brent; Krol, Magdalena

    2017-12-01

    The use of a deep geological repository (DGR) for the long-term disposal of used nuclear fuel is an approach currently being investigated by several agencies worldwide, including Canada's Nuclear Waste Management Organization (NWMO). Within the DGR, used nuclear fuel will be placed in copper-coated steel containers and surrounded by a bentonite clay buffer. While copper is generally thermodynamically stable, corrosion can occur due to the presence of sulphide under anaerobic conditions. As such, understanding transport of sulphide through the engineered barrier system to the used fuel container is an important consideration in DGR design. In this study, a three-dimensional (3D) model of sulphide transport in a DGR was developed. The numerical model is implemented using COMSOL Multiphysics, a commercial finite element software package. Previous sulphide transport models of the NWMO repository used a simplified one-dimensional system. This work illustrates the importance of 3D modelling to capture non-uniform effects, as results showed locations of maximum sulphide flux are 1.7 times higher than the average flux to the used fuel container. Copyright © 2017. Published by Elsevier B.V.

  12. Ontario Power Generation's proposed L and ILW deep geologic repository : an overview of geoscientific studies

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, M; Lam, T.; Luhowy, D.; McLay, J.; Semec, B.; Frizzell, R. [Nuclear Waste Management Organization, Toronto, ON (Canada)

    2009-07-01

    This paper reported on a multi-disciplinary geoscientific study to confirm the suitability of storing low and intermediate level radioactive waste in a deep geologic repository (DGR). The study is being conducted by the Nuclear Waste Management Organization on behalf of Ontario Power Generation (OPG). The DGR would involve the excavation of waste emplacement rooms within the Ordovician age argillaceous limestones 680 m beneath OPG's Bruce site near Tiverton, Ontario. The repository would require the excavation of nearly 890,000 m{sup 3} of rock to accommodate 200,000 m{sup 3} of radioactive waste within a 28 Ha repository footprint. A concrete floor will be poured to provide a stable base for stacking the waste packages. The first phase of the geoscientific site characterisation plan (GSCP) was prepared in 2005. The GSCP provides a comprehensive and internationally peer-reviewed basis for DGR-related geoscientific studies. The GSCP describes surface and sub-surface site characterization activities required to evaluate the technical suitability of the proposed DGR concept. The GSCP also provides a geoscientific basis for the post-closure safety assessment and contributes to the development of an integrated DGR safety case describing the expected long-term safety and potential impacts of the DGR. Interim results have shown that the middle-upper Ordovician formations proposed to host and enclose the DGR comprise a stable, saline and extremely low permeability groundwater regime. This paper provided an overview of the coordinated site-specific and regional studies to characterize the Bruce site and support the DGR safety case. The work program is scheduled for completion in late 2010 in support of the submittal of an Environmental Impact Statement and regulatory site Preparation/Construction License application in early 2011. 17 refs., 8 figs.

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

    International Nuclear Information System (INIS)

    Puhrer, A.; Bauer, C.

    2014-01-01

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

  14. Establishing deep geological repositories for radioactive waste in the United States of America

    International Nuclear Information System (INIS)

    Bennett, J.W.; Ballard, W.W. Jr.; Cooley, C.R.

    1984-01-01

    The paper describes, in broad terms, the interrelationship of the several regulations and recent legislation governing the National Waste Terminal Storage programme. The schedules of the first and second repositories are detailed, as are the interactions between the federal, state, and local governments. Limited portions of the Nuclear Regulatory Commission's regulations and the Environmental Protection Agency's standard are discussed to the extent that they affect the development schedules. (author)

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-08-15

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

  17. Geotechnical support and topical studies for nuclear waste geologic repositories: Annual report, fiscal year 1987

    International Nuclear Information System (INIS)

    1988-01-01

    This multidisciplinary project was initiated in fiscal year 1986. It comprises 11 reports in two major interrelated tasks: The technical assistance part of the project includes reviewing the progress of the major projects in the DOE Office of Civilian Radioactive waste Management (OCRWM) Program and advising the Engineering and Geotechnology Division on significant technical issues facing each project; analyzing geotechnical data, reports, tests, surveys and plans for the different projects; reviewing and commenting on major technical reports and other program documents such as Site Characterization Plans (SCP) and Study Plans; and providing scientific and technical input at technical meetings. The topical studies activity comprises studies on scientific and technical ions and issues of significance to in-situ testing, test analysis methods, and site characterization of nuclear waste geologic repositories. The subjects of study were selected based on discussions with DOE staff. One minor topic is a preliminary consideration and planning exercise for postclosure monitoring studies. The major task, with subtasks involving various geoscience disciplines, is a study of the mechanical, hydraulic, geophysical and geochemical properties of fractures in geologic rock masses

  18. The study of fracture mineralization and relationship with high level radioactive waste of deep geological repository

    International Nuclear Information System (INIS)

    Reyes, Cristina N.

    2003-01-01

    Extensive investigations of the Ordovician, Dinantian and Permo-Triassic rocks of the Sellafield area of northwest England were undertaken by United Kingdom Nirex Ltd. as a possible national site for geological disposal of intermediate and low-level radioactive waste. Very detailed studies of fracture mineralisation at Sellafield were thus put in hand by Nirex Ltd. and the results summarised by the British Geological Survey. Deep (up to 2 km) boreholes were put down with excellent core recovery. It is generally agreed that the most significant pathway for the escape of all but a very few radionuclides is by solution in and advection of groundwater. In this context, rock fracture systems are particularly important because they offer a potentially rapid pathway to the surface and the biosphere. One striking aspect of this work is that the fracture mineralisation seemingly records major and rapid fluctuations in redox conditions -sometimes during apparently continuous precipitation of cements (ferroan and non-ferroan calcites, dolomite). Carbonate cements record variations in Fe 2+ availability. Fe(III) precipitates also as oxide (hematite) and Fe(II) as sulphide (pyrite). This study focuses on these elements and valence states and also on Mn; another element susceptible to redox controls but known to respond differently from Fe. Shallow sub-surface stores or repositories would be more likely to have oxidising or fluctuating redox conditions. The mineralisation sequences documented at Sellafield are potentially promising in this context. Ferroan carbonate cements are sensitive indicators of later movement of oxidising ground waters. (author)

  19. Geotechnical support and topical studies for nuclear waste geologic repositories: Annual report, Fiscal Year 1986

    International Nuclear Information System (INIS)

    1986-11-01

    The multidisciplinary project was initiated in fiscal year 1986. It comprises two major interrelated parts: (1) Technical Assistance. This part of the project includes: (a) review of the progress of major projects in the DOE Office of Civilian Radioactive Waste Management Program and advise the Engineering and Geotechnology Division on significant technical issues facing each project; (b) analyze geotechnical data, reports, tests, surveys and plans for the different projects; (c) review and comment on major technical reports and other program documents such as site characterization plans and area characterization plans and (d) provide scientific and technical input at technical meetings. (2) Topical Studies. This activity comprises studies on scientific and technical topics, and issues of significance to in-situ testing, test analysis methods, and performance assessment of nuclear waste geologic repositories. The subjects of study were selected based on discussions with DOE staff. For fiscal year 1986, one minor and one major area of investigation were undertaken. The minor topic is a preliminary consideration and planning exercise for post-closure monitoring studies. The major topic, with subtasks involving various geoscience disciplines, is on the mechanical, hydraulic, geophysical and geochemical properties of fractures in geologic rock masses. The present report lists the technical reviews and comments made during the fiscal year and summarizes the technical progress of the topical studies

  20. Dynamic use of geoscience information to develop scientific understanding for a nuclear waste repository

    International Nuclear Information System (INIS)

    Cook, N.G.W.; Tsang, C.F.

    1990-01-01

    The development and safety evaluation of a nuclear waste geologic repository require a proper scientific understanding of the site response. Such scientific understanding depends on information from a number of geoscience disciplines, including geology, geophysics, geochemistry, geomechanics and hydrogeology. The information comes in four stages: (1) general regional survey data base, (2) surface-based testing, (3) exploratory shaft testing, and (4) repository construction and evaluation. A discussion is given on the dynamic use of the information through the different stages. We point out the need for abstracting, deriving and updating a quantitative spatial and process model (QSPM) to develop a scientific understanding of site responses as a crucial element in the dynamic procedure. 2 figs

  1. Seismic stability of the survey areas of potential sites for the deep geological repository of the spent nuclear fuel

    Czech Academy of Sciences Publication Activity Database

    Kaláb, Zdeněk; Šílený, Jan; Lednická, Markéta

    2017-01-01

    Roč. 15, č. 1 (2017), s. 486-493 E-ISSN 2391-5471 R&D Projects: GA MŠk LM2010008; GA MŠk(CZ) LM2015079 Institutional support: RVO:68145535 ; RVO:67985530 Keywords : deep geological repository * earthquake * seismicity * neo-deterministic analysis * probabilistic seismic hazard assessment Subject RIV: DC - Siesmology, Volcanology, Earth Structure; DC - Siesmology, Volcanology, Earth Structure (GFU-E) OBOR OECD: Environmental and geological engineering, geotechnics; Environmental and geological engineering, geotechnics (GFU-E) Impact factor: 0.745, year: 2016 https://www.degruyter.com/downloadpdf/j/phys.2017.15.issue-1/phys-2017-0055/phys-2017-0055.pdf

  2. Estimates of secondary waste production from operations at a proespective geologic repository in tuff

    International Nuclear Information System (INIS)

    Engelhard, M.P.; Jardine, L.J.

    1985-01-01

    In this paper, a method is outlined for estimating the volumes of solid and liquid radioactive wastes produced during the operation of a repository in tuff. Volume estimates were also developed based on a preliminary conceptual facility design. Based on a disposal rate of 3000 MTU/y of commercial spent fuel, the waste estimates ranged from 793 to 2464 m 3 /y of uncompacted solids and from 80,431 to 128,690 L/y of liquids, depending on the specific set of facility features assumed. The estimates of waste quantities were most dependent on variations in the ratio of truck to rail cask shipments received. The quantities of waste generated on site decreased as this ratio decreased. Although there are large uncertainties in the current estimates caused by the preliminary nature of the facility designs and the limited amount of engineering detail completed, the methodology can be used to refine estimates as the repository design progresses

  3. Canada's deep geological repository for used nuclear fuel - update on the site evaluation process and interweaving of aboriginal traditional knowledge

    International Nuclear Information System (INIS)

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

    2015-01-01

    The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management (APM), the approach selected by the Government of Canada for the long-term management of used nuclear fuel generated by Canadian nuclear reactors. The ultimate objective of APM is the centralized containment and isolation of Canada's used nuclear fuel in a Deep Geological Repository (DGR) in a suitable crystalline or sedimentary rock formation. In May 2010, the NWMO initiated a nine-step site selection process to seek an informed and willing community to host Canada's deep geological repository. As of April 2015, twenty-two communities expressed interest in learning more about the project. This paper provides an update on the site evaluation process and describes the approach, methods and criteria used in the assessments, focusing on geological and community well-being studies. Engagement and field activities to interweave Aboriginal Traditional Knowledge with western science are also discussed. (author)

  4. Process for selecting a site for Canada's deep geological repository for used nuclear fuel

    International Nuclear Information System (INIS)

    Facella, J.; Ben Belfadhel, M.; Patton, P.

    2012-01-01

    'Full Text:' 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 screenings of site suitability. This panel presentation 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 panel presentation will be conducted in three parts: site selection process and engagement, Aboriginal engagement and Technical evaluations, followed by a discussion. The presentation will outline how NWMO sought

  5. Probabilistic calculations and sensitivity analysis of parameters for a reference biosphere model assessing the potential exposure of a population to radionuclides from a deep geological repository

    Energy Technology Data Exchange (ETDEWEB)

    Staudt, Christian; Kaiser, Jan Christian [Helmholtz Zentrum Muenchen, Institute of Radiation Protection, Munich (Germany); Proehl, Gerhard [International Atomic Energy Agency, Division of Radiation, Transport and Waste Safety, Wagramerstrasse 5, 1400 Vienna (Austria)

    2014-07-01

    Radioecological models are used to assess the exposure of hypothetical populations to radionuclides. Potential radionuclide sources are deep geological repositories for high level radioactive waste. Assessment time frames are long since releases from those repositories are only expected in the far future, and radionuclide migration to the geosphere biosphere interface will take additional time. Due to the long time frames, climate conditions at the repository site will change, leading to changing exposure pathways and model parameters. To identify climate dependent changes in exposure in the far field of a deep geological repository a range of reference biosphere models representing climate analogues for potential future climate states at a German site were developed. In this approach, model scenarios are developed for different contemporary climate states. It is assumed that the exposure pathways and parameters of the contemporary biosphere in the far field of the repository will change to be similar to those at the analogue sites. Since current climate models cannot predict climate developments over the assessment time frame of 1 million years, analogues for a range of realistically possible future climate conditions were selected. These climate states range from steppe to permafrost climate. As model endpoint Biosphere Dose conversion factors (BDCF) are calculated. The radionuclide specific BDCF describe the exposure of a population to radionuclides entering the biosphere in near surface ground water. The BDCF are subject to uncertainties in the exposure pathways and model parameters. In the presented work, probabilistic and sensitivity analysis was used to assess the influence of model parameter uncertainties on the BDCF and the relevance of individual parameters for the model result. This was done for the long half-live radionuclides Cs-135, I-129 and U-238. In addition to this, BDCF distributions for nine climate reference regions and several scenarios were

  6. Preclosure seismic design methodology for a geologic repository at Yucca Mountain. Topical report YMP/TR-003-NP

    International Nuclear Information System (INIS)

    1996-10-01

    This topical report describes the methodology and criteria that the U.S. Department of Energy (DOE) proposes to use for preclosure seismic design of structures, systems, and components (SSCs) of the proposed geologic repository operations area that are important to safety. Title 10 of the Code of Federal Regulations, Part 60 (10 CFR 60), Disposal of High-Level Radioactive Wastes in Geologic Repositories, states that for a license to be issued for operation of a high-level waste repository, the U.S. Nuclear Regulatory Commission (NRC) must find that the facility will not constitute an unreasonable risk to the health and safety of the public. Section 60.131 (b)(1) requires that SSCs important to safety be designed so that natural phenomena and environmental conditions anticipated at the geologic repository operations area will not interfere with necessary safety functions. Among the natural phenomena specifically identified in the regulation as requiring safety consideration are the hazards of ground shaking and fault displacement due to earthquakes

  7. United States of America activities relative to the International Atomic Energy Agency (IAEA) initiative: Records management for deep geologic repositories

    Energy Technology Data Exchange (ETDEWEB)

    Warner, P.J.

    1997-03-01

    The International Atomic Energy Agency (IAEA) has conducted consultant and advisory meetings to prepare a Technical Document which is intended to provide guidance to all IAEA Member States (otherwise known as countries) that are currently planning, designing, constructing or operating a deep or near surface geological repository for the storage and protection of vitrified high-level radioactive waste, spent fuel waste and TRU-waste (transuranic). Eleven countries of the international community are presently in various stages of siting, designing, or constructing deep geologic repositories. Member States of the IAEA have determined that the principle safety of such completed and operation sites must not rely solely on long term institutional arrangements for the retention of information. It is believed that repository siting, design, operation and postoperation information should be gathered, managed and retained in a manner that will provide information to future societies over a very long period of time. The radionuclide life is 10,000 years thus the retention of information must outlive current societies, languages, and be continually migrated to new technology to assure retrieval. This presentation will provide an overview of the status of consideration and implementation of these issues within the United States efforts relative to deep geologic repository projects.

  8. United States of America activities relative to the International Atomic Energy Agency (IAEA) initiative: Records management for deep geologic repositories

    International Nuclear Information System (INIS)

    Warner, P.J.

    1997-01-01

    The International Atomic Energy Agency (IAEA) has conducted consultant and advisory meetings to prepare a Technical Document which is intended to provide guidance to all IAEA Member States (otherwise known as countries) that are currently planning, designing, constructing or operating a deep or near surface geological repository for the storage and protection of vitrified high-level radioactive waste, spent fuel waste and TRU-waste (transuranic). Eleven countries of the international community are presently in various stages of siting, designing, or constructing deep geologic repositories. Member States of the IAEA have determined that the principle safety of such completed and operation sites must not rely solely on long term institutional arrangements for the retention of information. It is believed that repository siting, design, operation and postoperation information should be gathered, managed and retained in a manner that will provide information to future societies over a very long period of time. The radionuclide life is 10,000 years thus the retention of information must outlive current societies, languages, and be continually migrated to new technology to assure retrieval. This presentation will provide an overview of the status of consideration and implementation of these issues within the United States efforts relative to deep geologic repository projects

  9. Geological repository layout for radioactive high level long lived waste in argillite

    International Nuclear Information System (INIS)

    Gaussen, JL

    2006-01-01

    In the framework of the 1991 French radioactive waste act, ANDRA has studied the feasibility of a geological repository in the argillite layer of the Bure site for high level long lived waste. This presentation is focussed on the underground facilities which constitute the specific component of this project. The preliminary underground layout which has been elaborated is based on four categories of data: - the waste characteristics and inventory; - the geological properties of the host argillite; - the long term performance objectives of the repository; - the specifications in terms of operation and reversibility. The underground facilities consist of two types of works: the access works (shafts and drifts) and the disposal cells. The function of the access works is to permit the implementation of two concurrent activities: the nuclear operations (transfer and emplacement of the disposal packages into the disposal cells) and the construction of the next disposal cells. The design of the drifts network which matches up to this function is also influenced by two other specifications: the minimization of the drift dimensions in order to limit their influence on the integrity of the geological formation and the necessity of a safe ventilation in case of fire. The resulting layout is a network of 4 parallel drifts (2 of them being dedicated to the operation, the other two being dedicated to the construction activities). The average diameter of these access drifts is 7 meters. The link between the surface and the underground is ensured by 4 shafts. The most important function of the disposal cells is to contribute to the long term performance of the repository. In this regard, the thermal and geotechnical considerations play an important role. The B wastes (intermediate level wastes) are not (or not very) exothermic. Consequently, the design of their disposal cells result mainly from geotechnical considerations. The disposal packages (made of concrete) are piled up in

  10. Sorption of plutonium and americium on repository, backfill and geological materials relevant to the JNFL low-level radioactive waste repository at Rokkasho-Mura

    International Nuclear Information System (INIS)

    Baston, G.M.N.; Berry, J.A.; Brownsword, M.; Heath, T.G.; Tweed, C.J.; Williams, S.J.

    1995-01-01

    An integrated program of batch sorption experiments and mathematical modeling has been carried out to study the sorption of plutonium and americium on a series of repository, backfill and geological materials relevant to the JNFL low-level radioactive waste repository at Rokkasho-Mura. The sorption of plutonium and americium on samples of concrete, mortar, sand/bentonite, tuff, sandstone and cover soil has been investigated. In addition, specimens of bitumen, cation and anion exchange resins, and polyester were chemically degraded. The resulting degradation product solutions, alongside solutions of humic and isosaccharinic acids were used to study the effects on plutonium sorption onto concrete, sand/bentonite and sandstone. The sorption behavior of plutonium and americium has been modeled using the geochemical speciation program HARPHRQ in conjunction with the HATCHES database

  11. Dissolution kinetics of smectite in geological repository system of TRU waste

    International Nuclear Information System (INIS)

    Sato, Tsutomu

    2005-02-01

    Extensive use of cement for encapsulation, mine timbering, and grouting purposes is envisaged in geological repositories of TRU waste. Degradation of cement materials in the repositories can produce a high pH pore fluid initially ranging from pH 13.0 to 13.5. The high pH pore fluids can migrate and react chemically with the host rock and bentonites which were employed to enhance repository's integrity. These chemical reactions can effect the capacity of the rocks and bentonites in retarding the migration of radionuclides. Smectite, main component of bentonite, can lose some of their desirable properties at the early stages of bentonite-cement fluid interaction. This has been a key research issue in performance assessment of TRU waste disposal. In this study, firstly, the factors affected on dissolution rate of smectite and equations describing dissolution rate were reviewed. Secondly, the effect of dissolved silica on the dissolution behavior of Na-montmorillonite was investigated. Bulk sample flow-through dissolution experiments at alkaline condition (pH 13.3) with different dissolved silica concentrations at different temperatures were performed. Titration experiments were also carried out at similar conditions. Atomic Force Microscopy (AFM) ex situ observations (i.e. on samples from flow-through experiments) was also performed to obtain the dissolution rate. Current results from bulk sample surface titration experiments indicate that dissolved silica has no pronounced effect on the surface titration behavior of Na-montmorillonite at any temperature. However, the trends for the surface titration behavior represent the averaged behavior of all particle sizes (i.e. including colloids) such that within an order of magnitude change cannot be quantified appreciably. Bulk flow-through dissolution experiments coupled with ex situ AFM observations indicate that there is also no effect of dissolved silica with comparatively low concentration of the reacting solution on

  12. An open repositories network development for medical teaching resources.

    Science.gov (United States)

    Soula, Gérard; Darmoni, Stefan; Le Beux, Pierre; Renard, Jean-Marie; Dahamna, Badisse; Fieschi, Marius

    2010-01-01

    The lack of interoperability between repositories of heterogeneous and geographically widespread data is an obstacle to the diffusion, sharing and reutilization of those data. We present the development of an open repositories network taking into account both the syntactic and semantic interoperability of the different repositories and based on international standards in this field. The network is used by the medical community in France for the diffusion and sharing of digital teaching resources. The syntactic interoperability of the repositories is managed using the OAI-PMH protocol for the exchange of metadata describing the resources. Semantic interoperability is based, on one hand, on the LOM standard for the description of resources and on MESH for the indexing of the latter and, on the other hand, on semantic interoperability management designed to optimize compliance with standards and the quality of the metadata.

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

    International Nuclear Information System (INIS)

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

    1983-03-01

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

  14. Development of repository-wide radionuclide transport model considering the effects of multiple sources

    International Nuclear Information System (INIS)

    Hatanaka, Koichiro; Watari, Shingo; Ijiri, Yuji

    1999-11-01

    Safety assessment of the geological isolation system according to the groundwater scenario has traditionally been conducted based on the signal canister configuration and then the safety of total system has been evaluated based on the dose rates which were obtained by multiplying the migration rates released from the engineered barrier and/or the natural barrier by dose conversion factors and total number of canisters disposed in the repository. The dose conversion factors can be obtained from the biosphere analysis. In this study, we focused on the effect of multiple sources due to the disposal of canisters at different positions in the repository. By taking the effect of multiple sources into consideration, concentration interference in the repository region is possible to take place. Therefore, radionuclide transport model/code considering the effect of concentration interference due to the multiple sources was developed to make assessments of the effect quantitatively. The newly developed model/code was verified through the comparison analysis with the existing radionuclide transport analysis code used in the second progress report. In addition, the effect of the concentration interference was evaluated by setting a simple problem using the newly developed analysis code. This results shows that the maximum park value of the migration rates from the repository was about two orders of magnitude lower than that based on single canister configuration. Since the analysis code was developed by assuming that all canisters disposed of along the one-dimensional groundwater flow contribute to the concentration interference in the repository region, the assumption should be verified by conducting two or three-dimensional analysis considering heterogeneous geological structure as a future work. (author)

  15. Environmental assessment for OPG's deep geologic repository for low and intermediate level waste

    International Nuclear Information System (INIS)

    Barker, D.; Rawlings, M.; Beal, A.

    2011-01-01

    The environmental assessment process for the Deep Geologic Repository (DGR) Project was initiated very early in the planning stages. Feasibility studies were initiated in 2003, after Ontario Power Generation (OPG) and the Municipality of Kincardine signed a Memorandum of Understanding agreeing to assess options for long-term management of low and intermediate level waste (L and ILW) options at the Bruce nuclear site. The location of the DGR, in the Municipality of Kincardine, is based on a willing and informed host community. The preferred approach, the DGR at the Bruce nuclear site, was advanced based on results of feasibility studies which looked at a number of options for long-term management of L&ILW and support from the local community and their elected representatives. The federal environmental assessment of the project was initiated following the signing of a Host Community Agreement and completion of a telephone poll, the results of which indicated that the majority of Municipality of Kincardine residents support the project. The environmental assessment began in 2006 as a comprehensive study and was ultimately referred to a joint review panel process in 2009. The environmental assessment considers the potential near-term effects of the construction and operations of the proposed project. Because of the nature of the project, the assessment of effects also considers long-term effects extending out to the million year time-frame, including effects of climate change, glaciations and seismic activity. (author)

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

    International Nuclear Information System (INIS)

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

    1981-02-01

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

  17. 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)

  18. 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.

  19. 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

  20. A new integrated approach to demonstrate the safe disposal of high-level radioactive waste and spent nuclear fuel in a geological repository

    International Nuclear Information System (INIS)

    Mueller-Hoeppe, N.; Krone, J.; Niehues, N.; Raitz von Frentz, R.

    2000-01-01

    Multi-barrier systems are accepted as the basic approach for long term environmental safe isolation of radioactive waste in geological repositories. Assessing the performance of natural and engineered barriers is one of the major difficulties in producing evidence of environmental safety for any radioactive waste disposal facility, due to the enormous complexity of scenarios and uncertainties to be considered. This paper outlines a new methodological approach originally developed basically for a repository in salt, but that can be transferred with minor modifications to any other host rock formation. The approach is based on the integration of following elements: (1) Implementation of a simple method and efficient criteria to assess and prove the tightness of geological and engineered barriers; (2) Using the method of Partial Safety Factors in order to assess barrier performance at certain reasonable level of confidence; (3) Integration of a diverse geochemical barrier in the near field of waste emplacement limiting systematically the radiological consequences from any radionuclide release in safety investigations and (4) Risk based approach for the assessment of radionuclide releases. Indicative calculations performed with extremely conservative assumptions allowed to exclude any radiological health consequences from a HLW repository in salt to a reference person with a safety level of 99,9999% per year. (author)

  1. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 10. Repository preconceptual design studies: granite

    International Nuclear Information System (INIS)

    1978-04-01

    This volume, Volume 10 ''Repository Preconceptual Design Studies: Granite,'' is one of a 23-volume series, ''Technical Support for GEIS: Radioactive Waste Isolation in Geologic Formations,'' Y/OWI/TM-36, which supplements the ''Contribution to Draft Generic Environmental Impact Statement on Commercial Waste Management: Radioactive Waste Isolation in Geologic Formations,'' Y/OWI/TM-44. The series provides a more complete technical basis for the preconceptual designs, resource requirements, and environmental source terms associated with isolating commercial LWR wastes in underground repositories in salt, granite, shale and basalt. Wastes are considered from three fuel cycles: uranium and plutonium recycling, no recycling of spent fuel and uranium-only recycling. This document describes a preconceptual design for a nuclear waste storage facility in granite. The facility design consists of several chambers excavated deep within a geologic formation together with access shafts and supportive surface structures. The facility design provides for: receiving and unloading waste containers; lowering them down shafts to the mine level; transporting them to the proper storage area, and emplacing them in mined storage rooms. Drawings of the facility design are contained in TM-36/11, ''Drawings for Repository Preconceptual Design Studies: Granite.''

  2. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 8. Repository preconceptual design studies: salt

    International Nuclear Information System (INIS)

    1978-04-01

    This volume, Volume 8 ''Repository Preconceptual Design Studies: Salt,'' is one of a 23-volume series, ''Technical Support for GEIS: Radioactive Waste Isolation in Geologic Formations,'' Y/OWI/TM-36, which supplements the ''Contribution to Draft Generic Environmental Impact Statement on Commercial Waste Management: Radioactive Waste Isolation in Geologic Formations,'' Y/OWI/TM-44. The series provides a more complete technical basis for the preconceptual designs, resource requirements, and environmental source terms associated with isolating commercial LWR wastes in underground repositories in salt, granite, shale and basalt. Wastes are considered from three fuel cycles: uranium and plutonium recycling, no recycling of spent fuel and uranium-only recycling. This document describes a preconceptual design for a nuclear waste storage facility in salt. The facility design consists of several chambers excavated deep within a geologic formation together with access shafts and supportive surface structures. The facility design provides for: receiving and unloading waste containers; lowering them down shafts to the mine level; transporting them to the proper storage area, and emplacing them in mined storage rooms. Drawings of the facility design are contained in TM-36/9, ''Drawings for Repository Preconceptual Design Studies: Salt.''

  3. 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)

  4. Guidelines for the operation and closure of deep geological repositories for the disposal of high level and alpha bearing wastes

    International Nuclear Information System (INIS)

    1991-10-01

    The operation and closure of a deep geological repository for the disposal of high level and alpha bearing wastes is a long term project involving many disciplines. This unique combination of nuclear operations in a deep underground location will require careful planning by the operating organization. The basic purpose of the operation stage of the deep repository is to ensure the safe disposal of the radioactive wastes. The purpose of the closure stage is to ensure that the wastes are safely isolated from the biosphere, and that the surface region can be returned to normal use. During these two stages of operation and closure, it is essential that both workers and the public are safely protected from radiation hazards, and that workers are protected from the hazards of working underground. For these periods of the repository, it is essential to carry out monitoring for purposes of radiological protection, and to continue testing and investigations to provide data for repository performance confirmation and for final safety assessment. Over the lengthy stages of operation and closure, there will be substantial feedback of experience and generation of site data. These will lead both to improved quality of operation and a better understanding of the site characteristics, thereby enhancing the confidence in the ability of the repository system to isolate the waste and protect future generations. 15 refs

  5. 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

  6. Hydrogeologic modelling in support of a proposed deep geologic repository in Canada for low and intermediate level radioactive waste - 16264

    International Nuclear Information System (INIS)

    Sykes, Jonathan F.; Normani, Stefano D.; Yin, Yong; Sykes, Eric A.; Jensen, Mark R.

    2009-01-01

    A Deep Geologic Repository (DGR) for Low and Intermediate Level radioactive waste has been proposed by Ontario Power Generation for the Bruce Nuclear Power Development site in Ontario, Canada. The DGR is to be constructed at a depth of about 680 m below ground surface within the argillaceous Ordovician limestone of the Cobourg Formation. This paper describes a regional-scale geologic conceptual model for the DGR site and analyzes flow system evolution using the FRAC3DVSOPG flow and transport model. This provides a framework for the assembly and integration of site-specific geo-scientific data that explains and illustrates the factors that influence the predicted long-term performance of the geosphere barrier. In the geologic framework of the Province of Ontario, the Bruce DGR is located at the eastern edge of the Michigan Basin. Borehole logs covering Southern Ontario combined with site specific data have been used to define the structural contours at the regional and site scale of the 31 sedimentary strata that may be present above the Precambrian crystalline basement rock. The regional-scale domain encompasses an 18.500 km 2 region extending from Lake Huron to Georgian Bay. The groundwater zone below the Devonian is characterized by units containing stagnant water having high concentrations of total dissolved solids that can exceed 300 g/l. The computational sequence involves the calculation of steady-state density independent flow that is used as the initial condition for the determination of pseudo-equilibrium for a density dependent flow system that has an initial TDS distribution developed from observed data. Long-term simulations that consider future glaciation scenarios include the impact of ice thickness and permafrost. The selection of the performance measure used to evaluate a groundwater system is important. The traditional metric of average water particle travel time is inappropriate for geologic units such as the Ordovician where solute transport is

  7. A study of the feasibility of monitoring sealed geological repositories using seismic sensors

    International Nuclear Information System (INIS)

    Garbin, H.D.; Herrington, P.B.; Kromer, R.P.

    1997-10-01

    Questions have arisen regarding the applicability of seismic sensors to detect mining (re-entry) with a tunnel boring machine (TBM). Unlike cut and blast techniques of mining which produce impulsive seismic signals, the TBM produces seismic signals which are of long duration. (There are well established techniques available for detecting and locating the sources of the impulsive signals.) The Yucca Mountain repository offered an opportunity to perform field evaluations of the capabilities of seismic sensors because during much of 1996, mining there was progressing with the use of a TBM. During the mining of the repository's southern branch, an effort was designed to evaluate whether the TBM could be detected, identified and located using seismic sensors. Three data acquisition stations were established in the Yucca Mountain area to monitor the TBM activity. A ratio of short term average to long term average algorithm was developed for use in detection based on the characteristics shown in the time series. For location of the source of detected signals, FK analysis was used on the array data to estimate back azimuths. The back azimuth from the 3 component system was estimated from the horizontal components. Unique features in the timing of the seismic signal were used to identify the source as the TBM

  8. A study of the feasibility of monitoring sealed geological repositories using seismic sensors

    International Nuclear Information System (INIS)

    Garbin, H.D.; Herrington, P.B.; Kromer, R.P.

    1999-01-01

    Questions have arisen regarding the applicability of seismic sensors to detect mining (re-entry) with a tunnel boring machine (TBM). Unlike cut and blast techniques of mining which produce impulsive seismic signals, the TBM produces seismic signals which are of long duration. (There are well established techniques available for detecting and locating the sources of the impulsive signals). The Yucca Mountain repository offered an opportunity to perform field evaluations of the capabilities of seismic sensors because during much of 1996, mining there was progressing with the use of a TBM. During the mining of the repository's southern branch, an effort was designed to evaluate whether the TBM could be detected, identified and located using seismic sensors. Three data acquisition stations were established in the Yucca Mountain area to monitor the TBM activity. A ratio of short term average to long term average algorithm was developed for use in detection based on the characteristics shown in the time series. For location of the source of detected signals, FK analysis was used on the array data to estimate back azimuths. The back azimuth from the 3 component system was estimated from the horizontal components. Unique features in the timing of the seismic signal were used to identify the source as the TBM. (author)

  9. 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

  10. Assessment of effectiveness of Geologic Isolation Systems. The development and application of a geologic simulation model

    International Nuclear Information System (INIS)

    Foley, M.G.; Petrie, G.M.

    1982-03-01

    The Geologic Simulation Model (GSM) developed under the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) project at the Pacific Northwest Laboratory for the Department of Energy is a quasi-deterministic process-response model which simulates the development of the geologic and hydrologic systems of a ground-water basin for a million years into the future. Effects of natural processes on the ground-water hydrologic system are modeled principally by rate equations. The combined effects and synergistic interactions of different processes are approximated by linear superposition of their effects during discrete time intervals in a stepwise-integration approach. The completed AEGIS GSM was used to generate 500 Monte Carlo simulations of the behavior of the geologic/hydrologic system affecting a hypothetical repository in the Pasco Basin over the next million years. These simulations used data which were not subjected to a review adequate to the needs of a real site performance assessment. However, the general care used in generating the data, and the overall behavior of the GSM suggest that the results are plausible at this time

  11. THE DECISION TO RECOMMEND YUCCA MOUNTAIN AND THE NEXT STEPS TOWARD LICENSED REPOSITORY DEVELOPMENT

    International Nuclear Information System (INIS)

    Barrett, L. H.

    2002-01-01

    After more than 20 years of carefully planned and reviewed scientific field work by the U.S. Department of Energy, the U.S. Geological Survey, and numerous other organizations, Secretary of Energy Abraham concluded in January that the Yucca Mountain site is suitable, within the meaning of the Nuclear Waste Policy Act, for development as a permanent nuclear waste and spent fuel repository. In February, the Secretary recommended to the President that the site be developed for licensed disposal of these wastes, and the President transmitted this recommendation to Congress. This paper summarizes key technical and national interest considerations that provided the basis for the recommendation. It also discusses the program's near-term plans for repository development if Congress designates the site

  12. Use of natural analogues to support radionuclide transport models for deep geological repositories for long lived radioactive wastes

    International Nuclear Information System (INIS)

    1999-10-01

    Plans to dispose high level and long lived radioactive wastes in deep geological repositories have raised a number of unique problems, mainly due to the very long time-scales which have to be considered. An important way to help to evaluate performance and provide confidence in the assessment of safety in the long term is to carry out natural analogue studies. Natural analogues can be regarded as long term natural experiments the results or outcome of which can be observed, but which, by definition, are uncontrolled by humans. Studies of natural analogues have been carried out for more than two decades, although the application of information from them is only relatively recently becoming scientifically well ordered. This report is part of a the IAEA's programme on radioactive waste management dealing with disposal system technology for high level and long lived radioactive waste. It presents the current status of natural analogue information in evaluating models for radionuclide transport by groundwater. In particular, emphasis is given to the most useful aspects of quantitative applications for model development and testing (geochemistry and coupled transport models). The report provides an overview of various natural analogues as reference for those planning to develop a research programme in this field. Recommendations are given on the use of natural analogues to engender confidence in the safety of disposal systems. This report is a follow up of Technical Reports Series No. 304 on Natural Analogues in Performance Assessments for the Disposal of Long Lived Radioactive Waste (1989)

  13. Proceedings of the scientific visit on crystalline rock repository development.

    Energy Technology Data Exchange (ETDEWEB)

    Mariner, Paul E.; Hardin, Ernest L.; Miksova, Jitka [RAWRA, Czech Republic

    2013-02-01

    A scientific visit on Crystalline Rock Repository Development was held in the Czech Republic on September 24-27, 2012. The visit was hosted by the Czech Radioactive Waste Repository Authority (RAWRA), co-hosted by Sandia National Laboratories (SNL), and supported by the International Atomic Energy Agency (IAEA). The purpose of the visit was to promote technical information exchange between participants from countries engaged in the investigation and exploration of crystalline rock for the eventual construction of nuclear waste repositories. The visit was designed especially for participants of countries that have recently commenced (or recommenced) national repository programmes in crystalline host rock formations. Discussion topics included repository programme development, site screening and selection, site characterization, disposal concepts in crystalline host rock, regulatory frameworks, and safety assessment methodology. Interest was surveyed in establishing a %E2%80%9Cclub,%E2%80%9D the mission of which would be to identify and address the various technical challenges that confront the disposal of radioactive waste in crystalline rock environments. The idea of a second scientific visit to be held one year later in another host country received popular support. The visit concluded with a trip to the countryside south of Prague where participants were treated to a tour of the laboratory and underground facilities of the Josef Regional Underground Research Centre.

  14. Geology of the Yucca Mountain Region, Chapter in Stuckless, J.S., ED., Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste

    Energy Technology Data Exchange (ETDEWEB)

    J.S. Stuckless; D. O' Leary

    2006-09-25

    Yucca Mountain has been proposed as the site for the Nation's first geologic repository for high-level radioactive waste. This chapter provides the geologic framework for the Yucca Mountain region. The regional geologic units range in age from late Precambrian through Holocene, and these are described briefly. Yucca Mountain is composed dominantly of pyroclastic units that range in age from 11.4 to 15.2 Ma. The proposed repository would be constructed within the Topopah Spring Tuff, which is the lower of two major zoned and welded ash-flow tuffs within the Paintbrush Group. The two welded tuffs are separated by the partly to nonwelded Pah Canyon Tuff and Yucca Mountain Tuff, which together figure prominently in the hydrology of the unsaturated zone. The Quaternary deposits are primarily alluvial sediments with minor basaltic cinder cones and flows. Both have been studied extensively because of their importance in predicting the long-term performance of the proposed repository. Basaltic volcanism began about 10 Ma and continued as recently as about 80 ka with the eruption of cones and flows at Lathrop Wells, approximately 10 km south-southwest of Yucca Mountain. Geologic structure in the Yucca Mountain region is complex. During the latest Paleozoic and Mesozoic, strong compressional forces caused tight folding and thrust faulting. The present regional setting is one of extension, and normal faulting has been active from the Miocene through to the present. There are three major local tectonic domains: (1) Basin and Range, (2) Walker Lane, and (3) Inyo-Mono. Each domain has an effect on the stability of Yucca Mountain.

  15. Geology of the Yucca Mountain Region, Chapter in Stuckless, J.S., ED., Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste

    International Nuclear Information System (INIS)

    J.S. Stuckless; D. O'Leary

    2006-01-01

    Yucca Mountain has been proposed as the site for the Nation's first geologic repository for high-level radioactive waste. This chapter provides the geologic framework for the Yucca Mountain region. The regional geologic units range in age from late Precambrian through Holocene, and these are described briefly. Yucca Mountain is composed dominantly of pyroclastic units that range in age from 11.4 to 15.2 Ma. The proposed repository would be constructed within the Topopah Spring Tuff, which is the lower of two major zoned and welded ash-flow tuffs within the Paintbrush Group. The two welded tuffs are separated by the partly to nonwelded Pah Canyon Tuff and Yucca Mountain Tuff, which together figure prominently in the hydrology of the unsaturated zone. The Quaternary deposits are primarily alluvial sediments with minor basaltic cinder cones and flows. Both have been studied extensively because of their importance in predicting the long-term performance of the proposed repository. Basaltic volcanism began about 10 Ma and continued as recently as about 80 ka with the eruption of cones and flows at Lathrop Wells, approximately 10 km south-southwest of Yucca Mountain. Geologic structure in the Yucca Mountain region is complex. During the latest Paleozoic and Mesozoic, strong compressional forces caused tight folding and thrust faulting. The present regional setting is one of extension, and normal faulting has been active from the Miocene through to the present. There are three major local tectonic domains: (1) Basin and Range, (2) Walker Lane, and (3) Inyo-Mono. Each domain has an effect on the stability of Yucca Mountain

  16. Application of Ga-Al discrimination plots in identification of high strength granitic host rocks for deep geological repository of high level radioactive waste

    International Nuclear Information System (INIS)

    Bajpai, R.K.; Narayan, P.K.; Trivedi, R.K.; Purohit, M.K.

    2010-01-01

    The permanent disposal of vitrified high level wastes and in some cases even spent fuel, is being planned in specifically designed and built deep geological repository located in the depth range of 500-600m in appropriate host rock at carefully selected sites. Such facilities are expected to provide very long term isolation and confinement to the disposed waste by means of long term mechanical stability of such structures that results from very high strength and homogeneity of the chosen rock, geochemical compatible environment around the disposed waste and general lack of groundwater. In Indian geological repository development programme, granites have been selected as target host rock and large scale characterization studies have been undertaken to develop database of mineralogy, petrology, geochemistry and rock mechanical characteristics. The paper proposes a new approach for demarcation of high strength homogeneous granite rocks from within an area of about 100 square kilometres wherein a cocktail of granites of different origins with varying rock mass characteristics co exists. The study area is characterised by the presence of A, S and I type granites toughly intermixed. The S type granites are derived from sedimentary parent material and therefore carry relics of parent fabric and at times undigested material with resultant reduction in their strength and increased inhomogeneity. On the other hand I type varieties are derived from igneous parents and are more homogeneous with sufficient strength. The A type granites are emplaced as molten mass in a complete non-tectonic setting with resultant homogeneous compositions, absence of tectonic fabric and very high strength. Besides they are silica rich with less vulnerability to alterations with time. Thus A type granites are most suited for construction of Deep Geological Repository. For developing a geochemical approach for establishing relation between chemical compositions and rock strength parameters, a

  17. Anaerobic corrosion of carbon steel under unsaturated conditions in a nuclear waste deep geological repository

    International Nuclear Information System (INIS)

    Kwong, G.; Wang, St.; Newman, R.C.

    2009-01-01

    Full text of publication follows: Anaerobic corrosion behaviour of carbon steel in humid conditions, but not submerged in aqueous solution, was studied based on hydrogen generation. Initial tests monitored the hydrogen evolution from carbon steel in a high humidity environment (≥ 75% RH) at near-ambient temperature (30 C) using a high sensitivity pressure gauge system (sensitivity of 0.01 μm.a -1 ). The presence of hydrogen in test runs that showed no, or minimal, pressure increase was confirmed by a solid-state potentiometric hydrogen sensor which has the capability of detecting hydrogen partial pressure as low as 10 -6 bar or a corrosion rate of 1.5 * 10 -4 μm.a -1 . Preliminary results indicate that a corrosion rate as high as 0.2 μm.a -1 can be sustained for steel coated with salt at 100% RH. Higher corrosion rates (as high as 0.8 μm.a -1 ) were obtained in less humid environment (71% RH). Without a salt deposit, pickled steel in humid environment (as high as 100% RH) also showed detectable corrosion for a period up to 800 hours, during which 0.8 kPa of hydrogen was accumulated prior to the apparent arrest of corrosion, representing a metal loss of 3 nm. Corrosion scales are also identified with x-ray photoelectron spectroscopy (XPS) as well as by mass change monitoring using a quartz crystal microbalance. Corrosion mechanisms and prediction for longer-term exposure will be discussed. Results will be useful in predicting long-term carbon steel corrosion behaviour and improving the current knowledge of hydrogen gas evolution in a deep geological repository for nuclear waste. (authors)

  18. Long-term Safety of a Geologic Repository: What does the public want to know?

    International Nuclear Information System (INIS)

    Kotra, Janet

    2008-01-01

    Janet Kotra of the U.S. NRC recounted the questions most frequently asked of the Commission's staff, concerning the long-term safety of the planned Yucca Mountain repository. The first question was related to who would decide whether the facility is safe enough. The next question linked to it is if regulatory staff is sufficiently qualified, and if they have access to independent sources of information or depend merely on the information provided by the implementer. The subsequent questions were about what criteria the regulator used and whether they were comprehensive enough. A separate group of questions addressed the safety of the technology, including the geologic features of the site, the engineered structures and the packaging of waste. Issues of documentation, operational control, long-term monitoring, oversight, and enforcement were also raised, along with the transparency of such processes and the accessibility of documents to the public. In addition, several questions were related to the fairness of decision making, public involvement, and the flexibility of the implementation process with regard to future knowledge and RD and D. Ms Kotra propounded that a single question was behind those cited above, namely whether one could rely on the regulator or not. Since it is not realistic to expect an overall consensus on the decision of the regulator agency, the goal should rather be to build confidence in the decision-making process. Key factors of confidence include openness on the part of the regulator and other decision-making institutions, and access to trustworthy representatives of these organisations

  19. Engineered barrier development for a nuclear waste repository in basalt

    International Nuclear Information System (INIS)

    Smith, M.J.

    1980-05-01

    The BWIP Engineered Barrier Program has been developed to provide an integrated approach to the development of site-specific Engineered Barrier assemblages for a repository located in basalt. The goal of this program is to specify engineered and natural barriers which will ensure that nuclear and non-radioactive hazardous materials emplaced in a repository in basalt do not exceed acceptable rates of release to the biosphere. A wide range of analytical and experimental activities related to the basalt repository environment, waste package environment, waste/barrier/rock interactions, and barrier performance assessment provide the basis for selection of systems capable of meeting licensing requirements. Work has concentrated on specifying and testing natural and man-made materials which can be used to plug boreholes in basalt and which can be used as multiple barriers to surround nuclear waste forms and containers. The Engineered Barriers Program is divided into two major activities: multiple barrier studies and borehole plugging. 8 figures, 4 tables

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

    Directory of Open Access Journals (Sweden)

    Yifeng Wang

    2013-12-01

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

  1. Impact of thermal constraints on the optimal design of high-level waste repositories in geologic media

    Energy Technology Data Exchange (ETDEWEB)

    Malbrain, C; Lester, R K [Massachusetts Inst. of Tech., Cambridge (USA). Dept. of Nuclear Engineering

    1982-12-01

    An approximate, semi-analytical heat conduction model for predicting the time-dependent temperature distribution in the region of a high-level waste repository has been developed. The model provides the basis for a systematic, inexpensive examination of the impact of several independent thermal design constraints on key repository design parameters and for determining the optimal set of design parameters which satisfy these constraints. Illustrative calculations have been carried out for conceptual repository designs for spent pressurized water reactor (PWR) fuel and reprocessed PWR high-level waste in salt and granite media.

  2. Melodie: a code for risk assessment of waste repositories in deep geological formations

    International Nuclear Information System (INIS)

    Lewi, J.; Mejon-Goula, M.J.; Cernes, A.

    1988-10-01

    In order to perform the safety evaluation of nuclear waste repositories, a global model, called MELODIE, is currently developed at the CEA/IPSN, in collaboration with order CEA teams and non-CEA like ENSMP (Ecole Nationale Superieure des Mines de Paris). The version now in operation allows to assess the radiological consequences due to a repository located in a granitic formation on a period of several hundred thousands of years. The calculations are based on models which represent the physical and chemical phenomena in connection with: the release of the radionuclides from the waste matrixes and through the engineered barriers; their transfer through the geosphere; their behaviour in the biosphere. Three separate models have been developed for each of these subjects; they are integrated in the code through a modular flexible dataprocessing structure which calls these computational modules with their optimal time step and extracts the data from the data files where they are stored. In addition, a sensitivity and uncertainty analysis algorithm has been implemented into the code. It allows to evaluate the influence of the parameter values on the result and to assess the global uncertainty on it. After a quite general description of MELODIE, the calculations performed with it in the PAGIS (CCE) exercise: global dose calculations and ranking of the most important parameters through the sensitivity analysis, are presented. The studies performed only with the geosphere module of MELODIE (METIS), especially the participation to the HYDROCOIN (OECD/NEA) exercise, are also noticed. In addition, the main future development axes of MELODIE are outlined

  3. Conceptual waste package interim product specifications and data requirements for disposal of borosilicate glass defense high-level waste forms in salt geologic repositories

    International Nuclear Information System (INIS)

    1983-06-01

    The conceptual waste package interim product specifications and data requirements presented are applicable specifically to the normal borosilicate glass product of the Defense Waste Processing Facility (DWPF). They provide preliminary numerical values for the defense high-level waste form parameters and properties identified in the waste form performance specification for geologic isolation in salt repositories. Subject areas treated include containment and isolation, operational period safety, criticality control, waste form/production canister identification, and waste package performance testing requirements. This document was generated for use in the development of conceptual waste package designs in salt. It will be revised as additional data, analyses, and regulatory requirements become available

  4. 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)

  5. Status of Equipment Development for a High-Level Waste Repository in Germany

    International Nuclear Information System (INIS)

    Biurrun, E.; Haverkamp, B.; Filbert, W.; Bollingerfehr, W.; Graf, R.

    2009-01-01

    In Germany, a potential site for a deep geological repository mainly for heat generating high-level waste was selected back on February 22, 1977: a salt dome located near the village of Gorleben, at the shores of the Elbe River in Northern Germany. Concurrent with site exploration from the surface, and later exploration mine construction, a large-scale R and D effort was conducted to have the science and technology needed to license and later operate a repository available when needed. An important part of these efforts was the development and 1:1 scale demonstration of all technologies required to run a repository, which had not been state-of-the-art. Underground exploration of the Gorleben site has come to a moratorium due to political decisions taken by the former Federal Government formed by a coalition between the Social Democrats and the Green Party back in 2000. However, research and development in regard to emplacement techniques and equipment has continued. This paper reflects the consistent, long-term technological effort that has led to having available all advanced technologies required to run a repository for spent fuel and HLW. The paper details previous achievements and points at present optimization work. (authors)

  6. Performance assessment development for a LILW repository in Slovenia

    International Nuclear Information System (INIS)

    Zeleznik, N.; Mele, I.

    2001-01-01

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

  7. Technical expertise on the safety of the proposed geological repository sites. Planning for geological deep repositories, step 1; Sicherheitstechnisches Gutachten zum Vorschlag geologischer Standortgebiete. Sachplan geologische Tiefenlager, Etappe 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-01-15

    On October 17, 2010, on request of those Swiss government institutions responsible for the disposal of radioactive wastes, the National Co-operative for the Disposal of Radioactive Waste (NAGRA) presented its project concerning geological sites for the foreseen disposal of radioactive wastes to the Federal Authorities. According to the present disposal concept, two types of repository are foreseen: one for highly radioactive wastes (HAA) and the other for low radioactive and intermediate-level radioactive wastes (SMA). If a site fulfils the necessary conditions for both HAA as well as for SMA, a combined site for both types of waste may be chosen. As a qualified control authority in Switzerland, the Federal Nuclear Safety Inspectorate (ENSI) has to examine the quality of the NAGRA proposals from the point of view of the nuclear safety of the sites. The project for deep underground waste disposal first defines the process and the criteria according to which sites for the geological storage of all types of radioactive wastes in Switzerland have to be chosen. The choice is based on the actual knowledge of Swiss geology. After dividing the wastes into SMA and HAA, some large-scale areas are to be identified according to their suitability from the geological and tectonic points of view. NAGRA's division of waste into SMA and HAA is based on calculations of the long-term safety for a broad range of different rock types and geological situations and takes the different properties of all waste types into account. As a conclusion, a small portion of SMA has to be stored with {alpha}-toxic wastes in the HAA repository. The estimation of the total volume of wastes to be stored is based on 60 years of operation of the actual nuclear power plants, augmented with the wastes from possible replacement plants with a total power of 5 GW{sub e} during a further 60 years. The safety concept of the repository is based on passive systems using technical and natural barriers. The

  8. Experiences from risk communication in the siting of a geological repository for high level waste in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Thegerstroem, C.; Engstroem, S. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    1999-12-01

    SKB is planning in the year 2001 to designate two siting alternatives for further site characterisation. The work in the municipalities of Oesthammar, Nykoeping, Oskarshamn and Tierp is taking place in an atmosphere of constructive discussions. There is a growing feeling in Sweden among broad categories of the public that the nuclear waste exists and should be taken care of by our generation, without many of these people ever getting positive to the use of nuclear energy. While the NIMBY syndrome might still have a good grip on some, there has never been a more constructive debate about the nuclear waste than now, even though there still is a lot of work to do. Siting a geological repository for high level waste puts our democratic system under hard tests. The decision making process is about openness, skills in interacting with the public, respect of people's fears and concerns and at last but not the least independent, competent and visible participation by other stakeholders (politicians locally and nationally, regulatory bodies etc). Good skills in risk communication are important ingredients that might facilitate SKB's task as a developer. Far more important however, is the trust we might get from past and present record of handling the waste and from the way we work and behave in the feasibility studies in the municipalities where SKB is involved.

  9. Experiences from risk communication in the siting of a geological repository for high level waste in Sweden

    International Nuclear Information System (INIS)

    Thegerstroem, C.; Engstroem, S.

    1999-01-01

    SKB is planning in the year 2001 to designate two siting alternatives for further site characterisation. The work in the municipalities of Oesthammar, Nykoeping, Oskarshamn and Tierp is taking place in an atmosphere of constructive discussions. There is a growing feeling in Sweden among broad categories of the public that the nuclear waste exists and should be taken care of by our generation, without many of these people ever getting positive to the use of nuclear energy. While the NIMBY syndrome might still have a good grip on some, there has never been a more constructive debate about the nuclear waste than now, even though there still is a lot of work to do. Siting a geological repository for high level waste puts our democratic system under hard tests. The decision making process is about openness, skills in interacting with the public, respect of people's fears and concerns and at last but not the least independent, competent and visible participation by other stakeholders (politicians locally and nationally, regulatory bodies etc). Good skills in risk communication are important ingredients that might facilitate SKB's task as a developer. Far more important however, is the trust we might get from past and present record of handling the waste and from the way we work and behave in the feasibility studies in the municipalities where SKB is involved

  10. OPG's deep geologic repository for low and intermediate level waste - public participation and aboriginal engagement

    International Nuclear Information System (INIS)

    Wilson, M.

    2011-01-01

    Ontario Power Generation (OPG)'s Public Participation and Aboriginal Engagement Program for the proposed Deep Geologic Repository (DGR) for low and intermediate level waste (L and ILW) began with the signing of a Memorandum of Understanding (MOU) in 2002 between OPG and the Municipality of Kincardine. The MOU set out the terms under which the two parties would jointly study the feasibility of different options for the long-term management of L and ILW at the Bruce nuclear site. A consultant, independent from both the Municipality of Kincardine and OPG, was retained to manage the assessment of options as well as a communication plan to ensure the public and Aboriginal peoples were kept apprised of all activities associated with the MOU. This early commitment to transparency and openness, with its ensuing opportunities for the public and Aboriginal peoples to become informed, ask questions, and engage in meaningful two-way dialogue about the early assessment of options, established the foundation and later became the hallmark of the DGR Project's Public Participation and Aboriginal Engagement program. This paper provides an overview of the development, nature and results of that program as it has evolved through the early investigative stages of options and through the environmental assessment and licencing process for the proposed DGR Project. (author)

  11. Terminology development towards harmonizing multiple clinical neuroimaging research repositories.

    Science.gov (United States)

    Turner, Jessica A; Pasquerello, Danielle; Turner, Matthew D; Keator, David B; Alpert, Kathryn; King, Margaret; Landis, Drew; Calhoun, Vince D; Potkin, Steven G; Tallis, Marcelo; Ambite, Jose Luis; Wang, Lei

    2015-07-01

    Data sharing and mediation across disparate neuroimaging repositories requires extensive effort to ensure that the different domains of data types are referred to by commonly agreed upon terms. Within the SchizConnect project, which enables querying across decentralized databases of neuroimaging, clinical, and cognitive data from various studies of schizophrenia, we developed a model for each data domain, identified common usable terms that could be agreed upon across the repositories, and linked them to standard ontological terms where possible. We had the goal of facilitating both the current user experience in querying and future automated computations and reasoning regarding the data. We found that existing terminologies are incomplete for these purposes, even with the history of neuroimaging data sharing in the field; and we provide a model for efforts focused on querying multiple clinical neuroimaging repositories.

  12. Release consequence analysis for a hypothetical geologic radioactive waste repository in hard rock

    International Nuclear Information System (INIS)

    1979-12-01

    This report makes an evaluation of the long-term behaviour of the wastes placed in a hard rock repository. Impacts were analyzed for the seven reference fuel cycles of WG 7. The reference repository for this study is for granitic rock or gneiss as the host rock. The descriptions of waste packages and repository facilities used in this study represent only one of many possible designs based on the multiple barriers concept. The repository's size is based on a nuclear economy producing 100 gigawatts of electricity per year for 1 year. The objective of the modeling efforts presented in this study is to predict the rate of transport of radioactive contaminants from the repository through the geosphere to the biosphere and thus determine an estimate of the potential dose to humans so that the release consequence impacts of the various fuel cycles can be compared. Currently available hydrologic, leach, transport, and dose models were used in this study

  13. Characterizing the proposed geologic repository for high-level radioactive waste at Yucca Mountain, Nevada: hydrology and geochemistry

    Science.gov (United States)

    Stuckless, John S.; Levich, Robert A.

    2012-01-01

    This hydrology and geochemistry volume is a companion volume to the 2007 Geological Society of America Memoir 199, The Geology and Climatology of Yucca Mountain and Vicinity, Southern Nevada and California, edited by Stuckless and Levich. The work in both volumes was originally reported in the U.S. Department of Energy regulatory document Yucca Mountain Site Description, for the site characterization study of Yucca Mountain, Nevada, as the proposed U.S. geologic repository for high-level radioactive waste. The selection of Yucca Mountain resulted from a nationwide search and numerous committee studies during a period of more than 40 yr. The waste, largely from commercial nuclear power reactors and the government's nuclear weapons programs, is characterized by intense penetrating radiation and high heat production, and, therefore, it must be isolated from the biosphere for tens of thousands of years. The extensive, unique, and often innovative geoscience investigations conducted at Yucca Mountain for more than 20 yr make it one of the most thoroughly studied geologic features on Earth. The results of these investigations contribute extensive knowledge to the hydrologic and geochemical aspects of radioactive waste disposal in the unsaturated zone. The science, analyses, and interpretations are important not only to Yucca Mountain, but also to the assessment of other sites or alternative processes that may be considered for waste disposal in the future. Groundwater conditions, processes, and geochemistry, especially in combination with the heat from radionuclide decay, are integral to the ability of a repository to isolate waste. Hydrology and geochemistry are discussed here in chapters on unsaturated zone hydrology, saturated zone hydrology, paleohydrology, hydrochemistry, radionuclide transport, and thermally driven coupled processes affecting long-term waste isolation. This introductory chapter reviews some of the reasons for choosing to study Yucca Mountain as a

  14. Characterizing the proposed geologic repository for high-level radioactive waste at Yucca Mountain, Nevada--hydrology and geochemistry

    Science.gov (United States)

    Stuckless, John S.; Levich, Robert A.

    2012-01-01

    This hydrology and geochemistry volume is a companion volume to the 2007 Geological Society of America Memoir 199, The Geology and Climatology of Yucca Mountain and Vicinity, Southern Nevada and California, edited by Stuckless and Levich. The work in both volumes was originally reported in the U.S. Department of Energy regulatory document Yucca Mountain Site Description, for the site characterization study of Yucca Mountain, Nevada, as the proposed U.S. geologic repository for high-level radioactive waste. The selection of Yucca Mountain resulted from a nationwide search and numerous committee studies during a period of more than 40 yr. The waste, largely from commercial nuclear power reactors and the government's nuclear weapons programs, is characterized by intense penetrating radiation and high heat production, and, therefore, it must be isolated from the biosphere for tens of thousands of years. The extensive, unique, and often innovative geoscience investigations conducted at Yucca Mountain for more than 20 yr make it one of the most thoroughly studied geologic features on Earth. The results of these investigations contribute extensive knowledge to the hydrologic and geochemical aspects of radioactive waste disposal in the unsaturated zone. The science, analyses, and interpretations are important not only to Yucca Mountain, but also to the assessment of other sites or alternative processes that may be considered for waste disposal in the future. Groundwater conditions, processes, and geochemistry, especially in combination with the heat from radionuclide decay, are integral to the ability of a repository to isolate waste. Hydrology and geochemistry are discussed here in chapters on unsaturated zone hydrology, saturated zone hydrology, paleohydrology, hydrochemistry, radionuclide transport, and thermally driven coupled processes affecting long-term waste isolation. This introductory chapter reviews some of the reasons for choosing to study Yucca Mountain as a

  15. Framework and Challenges for Initiating Multinational Cooperation for the Development of a Radioactive Waste Repository

    International Nuclear Information System (INIS)

    2016-01-01

    This publication is concerned with radioactive waste that requires geological disposal. It discusses the partnership arrangements necessary for the development of a multinational repository for disposal of this waste, but it also emphasizes that countries should not rely solely on a multinational solution and should in addition have coherent national plans for disposal (a dual track strategy). The publication focuses on multinational approaches based on the IAEA scenario for cooperation among countries in joint projects for the establishment of a shared geological repository. It describes the phased approach that would be needed, indicating the decision processes to be undertaken by partners in the multinational project, both within a national context and in the scope of the joint endeavour. It highlights a wide range of legal and institutional aspects, including the contractual obligations among partners, the economic and financial arrangements, liabilities, nuclear security, regulatory and legislative aspects, waste transportation arrangements, and social issues. It also addresses the uncertainties and risks involved in the implementation of a multinational repository

  16. Staff technical position on investigations to identify fault displacement hazards and seismic hazards at a geologic repository

    International Nuclear Information System (INIS)

    McConnell, K.I.; Blackford, M.E.; Ibrahim, A.K.

    1992-07-01

    The purpose of this Staff Technical Position (STP) is to provide guidance to the US Department of Energy (DOE) on acceptable geologic repository investigations that can be used to identify fault displacement hazards and seismic hazards. ne staff considers that the approach this STP takes to investigations of fault displacement and seismic phenomena is appropriate for the collection of sufficient data for input to analyses of fault displacement hazards and seismic hazards, both for the preclosure and postclosure performance periods. However, detailed analyses of fault displacement and seismic data, such as those required for comprehensive assessments of repository performance, may identify the need for additional investigations. Section 2.0 of this STP describes the 10 CFR Part 60 requirements that form the basis for investigations to describe fault displacement hazards and seismic hazards at a geologic repository. Technical position statements and corresponding discussions are presented in Sections 3.0 and 4.0, respectively. Technical position topics in this STP are categorized thusly: (1) investigation considerations, (2) investigations for fault-displacement hazards, and (3) investigations for seismic hazards

  17. The Use of Numerical Models in Support of Site Characterization and Performance Assessment Studies of Geological Repositories. Results of an IAEA Coordinated Research Project 2005-2010

    International Nuclear Information System (INIS)

    2013-10-01

    The siting, development and operation of waste disposal facilities, and the related safety issues, have been described in many IAEA publications. The safe management and disposal of radioactive waste from the nuclear fuel cycle remains a necessary condition for future development of nuclear energy. In particular, the disposal of high level waste and spent nuclear fuel in geological repositories, despite having been studied worldwide over the past several decades, still requires full scale demonstration through safe implementation, as planned at the national level in Finland and Sweden by 2020 and 2023, respectively, and in France by 2025. Safety assessment techniques are currently applicable to potential facility location and development through a quite large range of approaches and methodologies. By implementing research activities through coordinated research projects (CRPs), the IAEA enables research institutes in both developing and developed Member States to collaborate on research topics of common interest. In response to requests by several Member States in different networks and platforms dealing with waste disposal, in 2005 a CRP on The Use of Numerical Models in Support of Site Characterization and Performance Assessment Studies of Geological Repositories was proposed and developed to transfer modelling expertise and numerical simulation technology to countries needing them for their national nuclear waste management programmes. All Member States involved in this CRP have acquired the scientific basis for, and expertise in, the site characterization process, including test design, data analysis, model calibration, model validation, predictive modelling, sensitivity analysis and uncertainty propagation analysis. This expertise is documented in this publication, in which numerical modelling is used to address the pertinent issue of site characterization and its impact on safety, using data and information from a potential repository site

  18. Decommissioning of surface facilities associated with repositories for the deep geological disposal of high-level nuclear wastes

    International Nuclear Information System (INIS)

    Heckman, R.A.

    1978-11-01

    A methodology is presented in this paper to evaluate the decommissioning of the surface facilities associated with repositories for the deep geological disposal of high-level nuclear wastes. A cost/risk index (figure of merit), expressed as $/manrem, is proposed as an evaluation criteria. On the basis of this cost/risk index, we gain insight into the advisability of adapting certain decontamination design options into the original facility. Three modes are considered: protective storage, entombment, and dismantlement. Cost estimates are made for the direct labor involved in each of the alternative modes for a baseline design case. Similarly, occupational radiation exposures are estimated, with a larger degree of uncertainty, for each of the modes. Combination of these estimates produces the cost/risk index. To illustrate the methodology, an example using a preliminary baseline repository design is discussed

  19. Geology and hydrogeology of the proposed nuclear waste repository at Yucca Mountain, Nevada and the surrounding area

    International Nuclear Information System (INIS)

    Mattson, S.R.; Broxton, D.E.; Buono, A.; Crowe, B.M.; Orkild, P.P.

    1989-01-01

    In late 1987 Congress issued an amendment to the Nuclear Waste Policy Act of 1982 which directed the characterization of Yucca Mountain, Nevada as the only remaining potential site for the Nation's first underground high-level radioactive waste repository. The evaluation of a potential underground repository is guided and regulated by policy established by the Department of Energy (DOE), Nuclear Regulatory Commission (NRC), Environmental Protection Agency (EPA), Department of Transportation (DOT), and the US Congress. The Yucca Mountain Project is the responsibility of the DOE. The purpose of this field trip is to introduce the present state of geologic and hydrologic knowledge concerning this site. This report describes the field trip. 108 refs., 6 figs., 1 tab

  20. Vitrification treatment options for disposal of greater-than-Class-C low-level waste in a deep geologic repository

    International Nuclear Information System (INIS)

    Fullmer, K.S.; Fish, L.W.; Fischer, D.K.

    1994-11-01

    The Department of Energy (DOE), in keeping with their responsibility under Public Law 99-240, the Low-Level Radioactive Waste Policy Amendments Act of 1985, is investigating several disposal options for greater-than-Class C low-level waste (GTCC LLW), including emplacement in a deep geologic repository. At the present time vitrification, namely borosilicate glass, is the standard waste form assumed for high-level waste accepted into the Civilian Radioactive Waste Management System. This report supports DOE's investigation of the deep geologic disposal option by comparing the vitrification treatments that are able to convert those GTCC LLWs that are inherently migratory into stable waste forms acceptable for disposal in a deep geologic repository. Eight vitrification treatments that utilize glass, glass ceramic, or basalt waste form matrices are identified. Six of these are discussed in detail, stating the advantages and limitations of each relative to their ability to immobilize GTCC LLW. The report concludes that the waste form most likely to provide the best composite of performance characteristics for GTCC process waste is Iron Enriched Basalt 4 (IEB4)

  1. Evaluation of the heat transfer in a geological repository concept containing PWR, VHTR and hybrid ads-fission spent fuels

    Energy Technology Data Exchange (ETDEWEB)

    Jonusan, Raoni A.S.; Pereira, Fernando; Velasquez, Carlos E.; Salome, Jean A.D.; Cardoso, Fabiano; Pereira, Claubia; Fortini, Angela, E-mail: claubia@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2017-11-01

    The investigation of the thermal behavior of spent fuel (SF) materials is essential to determining appropriate potential sites to accommodate geological repositories as well as the design of canisters, considering their potential risk to people health and of environmental contamination. This work presents studies of the temperature in a canister containing spent fuels discharged from Pressurized Water Reactor (PWR), Very High-Temperature Reactor (VHTR) and Accelerator-Driven Subcritical Reactor System (ADS) reactor systems in a geological repository concept. The thermal analyses were performed with the software ANSYS, which is widely used to solve engineering problems through the Finite Element Method. The ANSYS Transient Thermal module was used. The spent nuclear fuels were set as heat sources using data of previous studies derived from decay heat curves. The studies were based on comparison of the mean temperature on a canister surface along the time under geological disposal conditions, for a same amount of each type of spent nuclear fuel evaluated. The results conclude that fuels from VHTR and ADS systems are inappropriate to be disposed in a standardized PWR canister, demanding new studies to determine the optimal amount of spent fuel and new internal canister geometries. It is also possible to conclude that the hypothetical situation of a single type of canister being used to accommodate different types of spent nuclear fuels is not technically feasible. (author)

  2. A Methodology to analyze the biosphere in the assessment of deep geological repositories for high level radioactive waste

    International Nuclear Information System (INIS)

    Pinedo, P.; Smith, G.

    1996-11-01

    This report summarizes the work done and the achievements reached within the R and D Project that IMA/CIEMAT has had with ENRESA during 1993-1995. The overall R and D Project has a wide radiological protection context, but the work reported here relates only to the development of a Methodology for considering the Biosphere sub-system in the assessments of deep geological repositories for high radioactive wastes (HLW). The main areas concerned within the Methodology have to do with the Biosphere structure and morphology in the long-term relevant to deep disposal of HLW: in the contexts of the assessment of these systems, and appropriate modelling of the behaviour of radionuclides released to the biosphere system and with the associated human exposure. This document first provides a review of the past and present international and national concerns about the biosphere modelling and its importance in relation to the definition of safety criteria. A joint ENRESA/ANDRA/IPSN/CIEMAT study about the definition and practical descriptions of the biosphere systems under different climatic states is then summarized. The Methodology developed by IMA/CIEMAT is outlined with an illustration of the way it works. Different steps and procedures are included for a better practical understanding of the software tools developed within the project to support the application of the Methodology. This methodology is widely based on an international working group on ''Reference Biospheres'', part of the BIOMOVS II Project. Specific software developments have been carried out in collaboration with Qunti Sci Itd and with the Polytechnical University of Madrid. (Author)

  3. Preclosure seismic design methodology for a geologic repository at Yucca Mountain. Revision 1

    International Nuclear Information System (INIS)

    1996-08-01

    This topical report is the second in a series of three reports being developed by the US Department of Energy (DOE) to document the preclosure seismic design of structures, systems, and components (SSCs) that are important to the radiological safety of the potential repository at Yucca Mountain, Nevada. The first topical report, Methodology to Assess Fault Displacement and Vibratory Ground Motion Hazards at Yucca Mountain, YMP/TR-002-NP, was submitted to the US Nuclear Regulatory Commission (NRC) staff for review and comment in 1994 and has been accepted by the staff. The DOE plans to implement this methodology in fiscal year 1997 to develop probabilistic descriptions of the vibratory ground motion hazard and the fault displacement hazard at the Yucca Mountain site. The second topical report (this report) describes the DOE methodology and acceptance criteria for the preclosure seismic design of SSCs important to safety. A third report, scheduled for fiscal year 1998, will document the results of the probabilistic seismic hazard assessment (conducted using the methodology in the first topical report) and the development of the preclosure seismic design inputs. This third report will be submitted to NRC staff for review and comment as a third topical report or as a design study report

  4. Human intrusion into geologic repositories for high-level radioactive waste: potential and prevention

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, F X [Nuclear Regulatory Commission, Washington, DC (USA). Office of Nuclear Regulatory Research

    1981-12-01

    Isolation of high-level radioactive waste over long periods of time requires protection not only from natural events and processes, but also from the deliberate or inadvertent activities of future societies. This paper evaluates the likelihood of inadvertent human intrusion due to the loss of societal memory of the repository site. In addition measures to prevent inadvertent intrusion, and to guide future societies in any decision to deliberately intrude into the repository are suggested.

  5. Role of waste packages in the safety of a high level waste repository in a deep geological formation

    International Nuclear Information System (INIS)

    Bretheau, F.; Lewi, J.

    1990-06-01

    The safety of a radioactive waste disposal facility lays on the three following barriers placed between the radioactive materials and the biosphere: the waste package; the engineered barriers; the geological barrier. The function assigned to each of these barriers in the performance assessment is an option taken by the organization responsible for waste disposal management (ANDRA in France), which must show that: expected performances of each barrier (confinement ability, life-time, etc.) are at least equal to those required to fulfill the assigned function; radiation protection requirements are met in all situations considered as credible, whether they be the normal situation or random event situations. The French waste management strategy is based upon two types of disposal depending on the nature and activity of waste packages: - surface disposal intended for low and medium level wastes having half-lives of about 30 years or less and alpha activity less than 3.7 MBq/kg (0.1 Ci/t), for individual packages and less than 0.37 MBq/kg (0.01 Ci/t) in the average. Deep geological disposal intended for TRU and high level wastes. The conditions of acceptance of packages in a surface disposal site are subject to the two fundamental safety rules no. I.2 and III.2.e. The present paper is only dealing with deep geological disposal. For deep geological repositories, three stages are involved: stage preceding definitive disposal (intermediate storage, transportation, handling, setting up in the disposal cavities); stage subsequent to definitive sealing of the disposal cavities but prior to the end of operation of the repository; stage subsequent to closure of the repository. The role of the geological barrier has been determined as the essential part of long term radioactivity confinement, by a working group, set up by the French safety authorities. Essential technical criteria relating to the choice of a site so defined by this group, are the following: very low permeability

  6. Geological disposal of high-level radioactive waste. Conceptual repository design in hard rock

    International Nuclear Information System (INIS)

    Beale, H.; Griffin, J.R.; Davies, J.W.; Burton, W.R.

    1980-01-01

    The paper gives an interim report on UK studies on possible designs for a repository for vitrified high-level radioactive waste in crystalline rock. The properties of the waste are described and general technical considerations of consequences of disposal in the rock. As an illustration, two basic designs are described associated with pre-cooling in an intermediate store. Firstly, a 'wet repository' is outlined wherein canisters are sealed up closely in boreholes in the rock in regions of low groundwater movement. Secondly, a 'dry repository' above sea level is described where emplacement in tunnels is followed by a loose backfill containing activity absorbers. A connection to deep permeable strata maintains water levels below emplacement positions. Variants on the two basic schemes (tunnel emplacement in a wet repository and in situ cooling) are also assessed. It is concluded that all designs discussed produce a size of repository feasible for construction in the UK. Further, (1) a working figure of 100 0 C per maximum rock temperature is not exceeded, (2) no insuperable engineering problems have so far been found, though rock mechanics studies are at an early stage; (3) it is not possible to discount the escape of a few long-lived 'man-made' isotopes. A minute increment to natural activity in the biosphere may occur from traces of uranium and its decay chains; (4) at this stage, all the designs are still possible candidates for the construction of a UK repository. (author)

  7. Cost Comparison for the Transfer of Select Calcined Waste Canisters to the Monitored Geologic Repository at Yucca Mountain, NV

    International Nuclear Information System (INIS)

    Michael B. Heiser; Clark B. Millet

    2005-01-01

    This report performs a life-cycle cost comparison of three proposed canister designs for the shipment and disposition of Idaho National Laboratory high-level calcined waste currently in storage at the Idaho Nuclear Technology and Engineering Center to the proposed national monitored geologic repository at Yucca Mountain, Nevada. Concept A (2 x 10-ft) and Concept B (2 x 15-ft) canisters are comparable in design, but they differ in size and waste loading options and vary proportionally in weight. The Concept C (5.5 x 17.5-ft) canister (also called the ''super canister''), while similar in design to the other canisters, is considerably larger and heavier than Concept A and B canisters and has a greater wall thickness. This report includes estimating the unique life-cycle costs for the three canister designs. Unique life-cycle costs include elements such as canister purchase and filling at the Idaho Nuclear Technology and Engineering Center, cask preparation and roundtrip consignment costs, final disposition in the monitored geologic repository (including canister off-loading and placement in the final waste disposal package for disposition), and cask purchase. Packaging of the calcine ''as-is'' would save $2.9 to $3.9 billion over direct vitrification disposal in the proposed national monitored geologic repository at Yucca Mountain, Nevada. Using the larger Concept C canisters would use 0.75 mi less of tunnel space, cost $1.3 billion less than 10-ft canisters of Concept A, and would be complete in 6.2 years

  8. 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

  9. Maximum flood hazard assessment for OPG's deep geologic repository for low and intermediate level waste

    International Nuclear Information System (INIS)

    Nimmrichter, P.; McClintock, J.; Peng, J.; Leung, H.

    2011-01-01

    Ontario Power Generation (OPG) has entered a process to seek Environmental Assessment and licensing approvals to construct a Deep Geologic Repository (DGR) for Low and Intermediate Level Radioactive Waste (L&ILW) near the existing Western Waste Management Facility (WWMF) at the Bruce nuclear site in the Municipality of Kincardine, Ontario. In support of the design of the proposed DGR project, maximum flood stages were estimated for potential flood hazard risks associated with coastal, riverine and direct precipitation flooding. The estimation of lake/coastal flooding for the Bruce nuclear site considered potential extreme water levels in Lake Huron, storm surge and seiche, wind waves, and tsunamis. The riverine flood hazard assessment considered the Probable Maximum Flood (PMF) within the local watersheds, and within local drainage areas that will be directly impacted by the site development. A series of hydraulic models were developed, based on DGR project site grading and ditching, to assess the impact of a Probable Maximum Precipitation (PMP) occurring directly at the DGR site. Overall, this flood assessment concluded there is no potential for lake or riverine based flooding and the DGR area is not affected by tsunamis. However, it was also concluded from the results of this analysis that the PMF in proximity to the critical DGR operational areas and infrastructure would be higher than the proposed elevation of the entrance to the underground works. This paper provides an overview of the assessment of potential flood hazard risks associated with coastal, riverine and direct precipitation flooding that was completed for the DGR development. (author)

  10. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 12. Repository preconceptual design studies: shale

    International Nuclear Information System (INIS)

    1978-04-01

    This document describes a preconceptual design for a nuclear waste storage facility in shale. The facility design consists of several chambers excavated deep within a geologic formation together with access shafts and supportive surface structures. The facility design provides for: receiving and unloading waste containers; lowering them down shafts to the mine level; transporting them to the proper storage area, and emplacing them in mined storage rooms. Drawings of the facility design are contained in TM-36/13, ''Drawings for Repository Preconceptual Design Studies: Shale.''

  11. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 14. Repository preconceptual design studies: basalt

    International Nuclear Information System (INIS)

    1978-04-01

    This document describes a preconceptual design for a nuclear waste storage facility in basalt. The facility design consists of several chambers excavated deep within a geologic formation together with access shafts and supportive surface structures. The facility design provides for: receiving and unloading waste containers; lowering them down shafts to the mine level; transporting them to the proper storage area and emplacing them in mined storage rooms. Drawings of the facility design are contained in TM-36/15, ''Drawings for Repository Preconceptual Design Studies: Basalt.''

  12. Construction and Operation of a Deep Geological Spent Fuel Repository in Sweden; Some Regulatory Aspects and Challenges

    International Nuclear Information System (INIS)

    Hedberg, Bengt

    2014-01-01

    The implementation of a deep geological spent fuel disposal concept in Sweden poses challenges on both implementer and regulator in many aspects. One such challenge is the application of the regulatory framework in a different situation compared to conventional process type nuclear facilities. A specific challenge in this regard is how to understand and address constraints from post-closure safety related to the construction and operation of the repository. The maybe most challenging aspect, however, is the unusually long time frame, i.e. many generations, for realization of the project. This paper addresses some of these challenges from a regulatory perspective. (authors)

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  14. Modeling The Inhalation Exposure Pathway In Performance Assessment Of Geologic Radioactive Waste Repository At Yucca Mountain

    International Nuclear Information System (INIS)

    M.A. Wasiolek

    2006-01-01

    Inhalation exposure pathway modeling has recently been investigated as one of the tasks of the BIOPROTA Project (BIOPROTA 2005). BIOPROTA was set up to address the key uncertainties in long term assessments of contaminant releases into the environment arising from radioactive waste disposal. Participants of this international Project include national authorities and agencies, both regulators and operators, with responsibility for achieving safe and acceptable radioactive waste management. The objective of the inhalation task was to investigate the calculation of doses arising from inhalation of particles suspended from soils within which long-lived radionuclides, particularly alpha emitters, had accumulated. It was recognized that site-specific conditions influence the choice of conceptual model and input parameter values. Therefore, one of the goals of the task was to identify the circumstances in which different processes included in specific inhalation exposure pathway models were important. This paper discusses evaluation of processes and modeling assumptions specific to the proposed repository at Yucca Mountain as compared to the typical approaches and other models developed for different assessments and project specific contexts. Inhalation of suspended particulates that originate from contaminated soil is an important exposure pathway, particularly for exposure to actinides such as uranium, neptunium and plutonium. Radionuclide accumulation in surface soil arises from irrigation of soil with contaminated water over many years. The level of radionuclide concentration in surface soil depends on the assumed duration of irrigation. Irrigation duration is one of the parameters used on biosphere models and it depends on a specific assessment context. It is one of the parameters addressed in this paper from the point of view of assessment context for the proposed repository at Yucca Mountain. The preferred model for the assessment of inhalation exposure uses

  15. Evaluation of engineering aspects of backfill placement for high level nuclear waste (HLW) deep geologic repositories

    International Nuclear Information System (INIS)

    Roberds, W.; Kleppe, J.; Gonano, L.

    1984-04-01

    This report includes the identification and subjective evaluation of alternative schemes for backfilling around waste packages and within emplacement rooms. The aspects of backfilling specifically considered in this study include construction and testing; costs have not been considered. However, because construction and testing are simply implementation and verification of design, a design basis for backfill is required. A generic basis has been developed for this study by first identifying qualitative performance objectives for backfill and then weighting each with respect to its potential influence on achieving the repository system performance objectives. Alternative backfill materials and additives have been identified and evaluated with respect to the perceived extent to which each combination can be expected to achieve the backfill design basis. Several distinctly different combinations of materials and additives which are perceived to have the highest potential for achieving the backfill design basis have been selected for further study. These combinations include zeolite/clinoptilolite, bentonite, muck, and muck mixed with bentonite. Feasible alternative construction and testing procedures for each selected combination have been discussed. Recommendations have been made regarding appropriate backfill schemes for hard rock (i.e., basalt at Hanford, Washington, tuff at Nevada Test Site, and generic granite) and salt (i.e., domal salt on the Gulf Coast and generic bedded salt). 27 references, 8 figures, 31 tables

  16. Preparing for Construction and Operation of Geological Repositories - Challenges to the Regulator and the Implementer. Proceedings of the Joint RF/IGSC Workshop, Issy-les-Moulineaux, France, 25-27 January 2012

    International Nuclear Information System (INIS)

    2014-01-01

    More radioactive waste management programmes are advancing to a new repository development phase and are preparing for the application of their construction license of a deep geological disposal facility. Such developmental progress brought along significant changes to repository development affecting both the waste management programme implementers and the regulators. New issues impacting both the regulatory authorities and the future facility operators include operational safety and reliability, increased demands on human resources, activities to ensure quality assurance, the additional requirements on information management system and management plans for construction work. To respond to new arising issues, the Radioactive Waste Management Committee (RWMC) of the OECD Nuclear Energy Agency (NEA) has agreed, as stated in the 2011-2016 Strategic Plan, that the Committee will focus on constituencies for the preparation of the construction and operation license of future deep geological repositories. In addition, the Committee will consider operational aspects of repository implementation, both connected to the operational safety and the impact on the post-closure long-term safety. In particular, the RWMC has approved the RWMC Regulator's Forum (RWMC-RF) and the Integration Group for the Safety Case (IGSC) to hold a joint workshop to explore challenging issues and practices in preparing for the application of the construction license of a geological repository. The joint workshop titled 'Preparing for Construction and Operation of Geological Repositories - Challenges to the Regulator and the Implementer' was held on January 25-27, 2012 at the NEA premises in Issy-les-Moulineaux, France. The key objective of the workshop was to identify, and exchange experience on, the current and future challenges faced by the implementers and the regulators when preparing for their application of a construction license of a geological repository. The workshop gave a

  17. Uranium, thorium and trace elements in geologic occurrences as analogues of nuclear waste repository conditions

    International Nuclear Information System (INIS)

    Wollenberg, H.A.; Brookins, D.G.; Cohen, L.H.; Flexser, S.; Abashian, M.; Murphy, M.; Williams, A.E.

    1984-01-01

    Contact zones between intrusive rocks and tuff, basalt, salt and granitic rock were investigated as possible analogues of nuclear waste repository conditions. Results of detailed studies of contacts between quartz monzonite of Laramide age, intrusive into Precambrian gneiss, and a Tertiary monzonite-tuff contact zone indicate that uranium, thorium and other trace elements have not migrated significantly from the more radioactive instrusives into the country rock. Similar observations resulted from preliminary investigations of a rhyodacite dike cutting basalt of the Columbia River plateau and a kimberlitic dike cutting bedded salt of the Salina basin. This lack of radionuclide migration occurred in hydrologic and thermal conditions comparable to, or more severe than those expected in nuclear waste repository environments and over time periods of the order of concern for waste repositories. Attention is now directed to investigation of active hydrothermal systems in candidate repository rock types, and in this regard a preliminary set of samples has been obtained from a core hole intersecting basalt underlying the Newberry caldera, Oregon, where temperatures presently range from 100 to 265 0 C. Results of mineralogical and geochemical investigations of this core should indicate the alteration mineralogy and behavior of radioelements in conditions analogous to those in the near field of a repository in basalt

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

    International Nuclear Information System (INIS)

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

    1982-05-01

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

  19. The development of a deep repository-progress in the UK

    International Nuclear Information System (INIS)

    Beale, H.; Mogg, C.S.

    1992-01-01

    United Kingdom Nirex Ltd, a company jointly owned by the major partners in the UK nuclear industry, is responsible for developing a deep disposal facility for low-level and intermediate-level radioactive waste. In July 1991 Nirex announced its intention to concentrate geological investigations at Sellafield, where BNFL's existing operations give rise to approximately 60% of the wastes destined for a repository. The main features of the Nirex design process, from early considerations through the main features of a preferred conceptual design and its advantages, are described. Subject to Nirex obtaining planning permission, following a Public Inquiry, the proposed program would allow the UK nuclear industry to fulfill its responsibilities with respect to declared Government policy by providing a safe deep geological disposal facility early in the next century. (author)

  20. 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

  1. Nuclear Regulatory Commission staff development of the license application review plan for a high-level radioactive waste repository

    International Nuclear Information System (INIS)

    Johnson, R.L.; Holonich, J.J.; Lee, M.P.; Delligatti, M.S.

    1993-01-01

    The Nuclear Regulatory Commission staff has recently started a new initiative to develop the License Application Review Plan (LARP) which the staff will use in its reviews of the U.S. Department of Energy's (DOE's) license application (LA) for a geologic repository for the disposal of high-level radioactive waste (HLW). This paper describes the staff's approach for developing the LARP, the development schedule and current status, the organization and content of the LARP, and the staff's LA review strategy. Therefore, it gives a preview of the draft LARP which will be made available in late 1993. It also describes how the LARP will be used as guidance to the staff in conducting reviews of regulatory and technical issues important to the licensing of a geologic repository. Finally, the benefits to the NRC staff, DOE, and other parties are discussed

  2. Hydrogeologic modelling in support of a proposed Deep Geologic Repository in Canada for low and intermediate level radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Sykes, J.F.; Normani, S.D.; Yin, Y. [Waterloo Univ., ON (Canada). Dept. of Civil and Environmental Engineering; Sykes, E.A.; Jensen, M.R. [Nuclear Waste Management Organization, Toronto, ON (Canada)

    2009-07-01

    Ontario Power Generation (OPG) has proposed the construction of a Deep Geologic Repository (DGR) for low and intermediate level radioactive waste at the Bruce site on the shore of Lake Huron near Tiverton, Ontario. The DGR is to be excavated at a depth of about 680 m within argillaceous limestones of Ordovician age. A saturated regional-scale and site-scale numerical modelling study has been completed in order to evaluate the safety of storing radioactive waste at the site and to better understand the geochemistry and hydrogeology of the formations surrounding the proposed DGR. This paper reported on the regional-scale base-case modelling and analysis of the measured pressure profile in deep boreholes at the DGR site. The numerical modelling study provided a framework to investigate the groundwater flow system as it relates to, and potentially affects, the safety and long-term performance of the DGR. A saturated groundwater flow model was also developed using FRAC3DVS-OPG. The objective of regional-scale groundwater modelling of the Paleozoic sedimentary sequence underlying southwestern Ontario was to provide a basis for the assembly and integration of site-specific geoscientific data and to explain the influence of parameter and scenario uncertainty on predicted long-term geosphere barrier performance. The base-case analysis showed that solute transport in the Ordovician and lower Silurian is diffusion dominant. For the base-case parameters, the estimated mean life expectancy for the proposed DGR is more than 8 million years. The possible presence of a gas phase in the rock between the Cambrian and the Niagaran was not considered in the analyses of this paper. 9 refs., 2 tabs., 10 figs.

  3. Modeling of irradiated graphite {sup 14}C transfer through engineered barriers of a generic geological repository in crystalline rocks

    Energy Technology Data Exchange (ETDEWEB)

    Poskas, Povilas; Grigaliuniene, Dalia, E-mail: Dalia.Grigaliuniene@lei.lt; Narkuniene, Asta; Kilda, Raimondas; Justinavicius, Darius

    2016-11-01

    There are two RBMK-1500 type graphite moderated reactors at the Ignalina nuclear power plant in Lithuania, and they are under decommissioning now. The graphite cannot be disposed of in a near surface repository, because of large amounts of {sup 14}C. Therefore, disposal of the graphite in a geological repository is a reasonable solution. This study presents evaluation of the {sup 14}C transfer by the groundwater pathway into the geosphere from the irradiated graphite in a generic geological repository in crystalline rocks and demonstration of the role of the different components of the engineered barrier system by performing local sensitivity analysis. The speciation of the released {sup 14}C into organic and inorganic compounds as well as the most recent information on {sup 14}C source term was taken into account. Two alternatives were considered in the analysis: disposal of graphite in containers with encapsulant and without it. It was evaluated that the maximal fractional flux of inorganic {sup 14}C into the geosphere can vary from 10{sup −} {sup 11} y{sup −} {sup 1} (for non-encapsulated graphite) to 10{sup −} {sup 12} y{sup −} {sup 1} (for encapsulated graphite) while of organic {sup 14}C it was about 10{sup −} {sup 3} y{sup −} {sup 1} of its inventory. Such difference demonstrates that investigations on the {sup 14}C inventory and chemical form in which it is released are especially important. The parameter with the highest influence on the maximal flux into the geosphere for inorganic {sup 14}C transfer was the sorption coefficient in the backfill and for organic {sup 14}C transfer – the backfill hydraulic conductivity. - Highlights: • Graphite moderated nuclear reactors are being decommissioned. • We studied interaction of disposed material with surrounding environment. • Specifically {sup 14}C transfer through engineered barriers of a geological repository. • Organic {sup 14}C flux to geosphere is considerably higher than inorganic

  4. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 22. Nuclear considerations for repository design

    International Nuclear Information System (INIS)

    1978-04-01

    This volume, Y/OWI/TM-36/22, ''Nuclear Considerations for Repository Design,'' is one of a 23-volume series, ''Technical Support for GEIS: Radioactive Waste Isolation in Geologic Formations,'' Y/OWI/TM-36, which supplements the ''Contribution to Draft Generic Environmental Impact Statement on Commercial Waste Management: Radioactive Waste Isolation in Geologic Formations,'' Y/OWI/TM-44. The series provides a more complete technical basis for the preconceptual designs, resource requirements, and environmental source terms associated with isolating commercial LWR wastes in underground repositories in salt, granite, shale and basalt. Wastes are considered from three fuel cycles: uranium and plutonium recycling, no recycling of spent fuel and uranium-only recycling. Included in this volume are baseline design considerations such as characteristics of canisters, drums, casks, overpacks, and shipping containers; maximum allowable and actual decay-heat levels; and canister radiation levels. Other topics include safeguard and protection considerations; occupational radiation exposure including ALARA programs; shielding of canisters, transporters and forklift trucks; monitoring considerations; mine water treatment; canister integrity; and criticality calculations

  5. Canada's Deep Geological Repository for Used Nuclear Fuel - Geo-scientific Site Evaluation Process - 13117

    Energy Technology Data Exchange (ETDEWEB)

    Blyth, Alec; Ben Belfadhel, Mahrez; Hirschorn, Sarah; Hamilton, Duncan; McKelvie, Jennifer [Nuclear Waste Management Organization, 22 St. Clair Avenue East, Toronto, Ontario M4T 2S3 (Canada)

    2013-07-01

    The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management (APM), the approach selected by the Government of Canada for long-term management of used nuclear fuel generated by Canadian nuclear reactors. The ultimate objective of APM is the centralized containment and isolation of Canada's used nuclear fuel in a Deep Geological Repository in a suitable rock formation at a depth of approximately 500 meters (m) (1,640 feet [ft]). In May 2010, the NWMO published a nine-step site selection process that serves as the road map to decision-making on the location for the deep geological repository. The safety and appropriateness of any potential site will be assessed against a number of factors, both technical and social in nature. The selected site will be one that can be demonstrated to be able to safely contain and isolate used nuclear fuel, protecting humans and the environment over the very long term. The geo-scientific suitability of potential candidate sites will be assessed in a stepwise manner following a progressive and thorough site evaluation process that addresses a series of geo-scientific factors revolving around five safety functions. The geo-scientific site evaluation process includes: Initial Screenings; Preliminary Assessments; and Detailed Site Evaluations. As of November 2012, 22 communities have entered the site selection process (three in northern Saskatchewan and 18 in northwestern and southwestern Ontario). (authors)

  6. Seismic stability of the survey areas of potential sites for the deep geological repository of the spent nuclear fuel

    Science.gov (United States)

    Kaláb, Zdeněk; Šílený, Jan; Lednická, Markéta

    2017-07-01

    This paper deals with the seismic stability of the survey areas of potential sites for the deep geological repository of the spent nuclear fuel in the Czech Republic. The basic source of data for historical earthquakes up to 1990 was the seismic website [1-]. The most intense earthquake described occurred on September 15, 1590 in the Niederroesterreich region (Austria) in the historical period; its reported intensity is Io = 8-9. The source of the contemporary seismic data for the period since 1991 to the end of 2014 was the website [11]. It may be stated based on the databases and literature review that in the period from 1900, no earthquake exceeding magnitude 5.1 originated in the territory of the Czech Republic. In order to evaluate seismicity and to assess the impact of seismic effects at depths of hypothetical deep geological repository for the next time period, the neo-deterministic method was selected as an extension of the probabilistic method. Each one out of the seven survey areas were assessed by the neo-deterministic evaluation of the seismic wave-field excited by selected individual events and determining the maximum loading. Results of seismological databases studies and neo-deterministic analysis of Čihadlo locality are presented.

  7. Experimental methodology to study radionuclide sorption and migration in geological formations and engineered barriers of waste repositories

    International Nuclear Information System (INIS)

    Rojo Sanz, H.

    2010-01-01

    In Spain, the waste management options include either the possibility of a final storage in a deep geological repository (DGR) or the centralized temporal surface disposal (CTS). DGRs are based in a multi-barrier concept with the geological barrier and including the vitrified waste, the metal containers and engineered barriers such as compacted bentonite and cement-based materials. On the other hand, CTS mainly considers concrete and cement to confine the metal canisters containing the waste. Radionuclide migration will mainly take place by the existence of chemical concentration gradients being thus diffusion the main transport mechanism or by the existence of hydraulic gradients due to the existence of water-conductive fractures. Radionuclide sorption/retention on the materials composing the natural and engineered barriers is the fundamental process controlling contaminant migration. The evaluation of sorption parameters and the understanding of the different mechanisms leading to radionuclide retention are very important issues. The study of diffusion processes is very relevant as well. This paper describes the main experimental methodologies applied to analyse radionuclide transport in the different barriers of radioactive repositories. Particularly we focused on obtaining of retention parameters as distribution coefficients, kd, or retardation factors, Rf, and diffusion coefficients of radionuclides. (Author) 6 refs.

  8. The hydrogeologic environment for a proposed deep geologic repository in Canada for low and intermediate level radioactive waste - 59285

    International Nuclear Information System (INIS)

    Sykes, Jonathan F.; Normani, Stefano D.; Yin, Yong; Jensen, Mark R.

    2012-01-01

    A Deep Geologic Repository (DGR) for low and intermediate level radioactive waste has been proposed by Ontario Power Generation for the Bruce nuclear site in Ontario, Canada. As proposed the DGR would be constructed at a depth of about 680 m below ground surface within the argillaceous Ordovician limestone of the Cobourg Formation. This paper describes the hydrogeology of the DGR site developed through both site characterization studies and regional-scale numerical modelling analysis. The analysis provides a framework for the assembly and integration of the site-specific geo-scientific data and examines the factors that influence the predicted long-term performance of the geosphere barrier. Flow system evolution was accomplished using both the density-dependent FRAC3DVS-OPG flow and transport model and the two-phase gas and water flow computational model TOUGH2-MP. In the geologic framework of the Province of Ontario, the DGR is located on the eastern flank of the Michigan Basin. Borehole logs covering Southern Ontario combined with site-specific data from 6 deep boreholes have been used to define the structural contours and hydrogeologic properties at the regional-scale of the modelled 31 sedimentary strata that may be partially present above the Precambrian crystalline basement rock. The regional-scale domain encompasses an approximately 18500 km 2 region extending from Lake Huron to Georgian Bay. The groundwater zone below the Devonian includes units containing stagnant water having high concentrations of total dissolved solids that can exceed 300 g/L. The Ordovician sediments are significantly under-pressured. The horizontal hydraulic conductivity for the Cobourg limestone is estimated to be 2x10 -14 m/s based on straddle-packer hydraulic tests. The low advective velocities in the Cobourg and other Ordovician units result in solute transport that is diffusion dominant with Peclet numbers less than 0:003 for a characteristic length of unity. Long

  9. Characterization of Swelling Clays as Components of the Engineered Barrier System for Geological Repositories. Results of an IAEA Coordinated Research Project 2002-2007

    International Nuclear Information System (INIS)

    2013-11-01

    At the request of the Member States, the IAEA coordinates research into subjects of common interest in the context of the peaceful application of nuclear technology. The coordinated research projects (CRPs) are intended to promote knowledge and technology transfer between Member States and are largely focused on subjects of prime interest to the international nuclear community. This report presents the results of a CRP carried out between 2002 and 2007 on the subject of swelling clays proposed for use as a component in the engineered barrier system (EBS) of the multibarrier concept for disposal of radioactive waste. In 2002, under the auspices of the IAEA, a number of Member States came together to form a Network of Centres of Excellence on Training in and Demonstration of Waste Disposal Technologies in Underground Research Facilities (URF Network). This network identified the general subject of the application of high swelling clays to seal repositories for radioactive waste, with specific emphasis on the isolation of high level radioactive waste from the biosphere, as being suitable for a CRP. Existing concepts for geological repositories for high level radioactive waste and spent nuclear fuel require the use of EBSs to ensure effective isolation of the radioactive waste. There are two major materials proposed for use in the EBS, swelling clay based materials and cementitious/concrete materials. These materials will be placed between the perimeter of the excavation and the waste container to fill the existing gap and ensure isolation of the waste within the canister (also referred to as a container in some EBS concepts) by supporting safety through retardation and confinement. Cementitious materials are industrially manufactured to consistent standards and are readily available in most locations and therefore their evaluation is of less value to Member States than that of swelling clays. There exists a considerable range of programme development regarding

  10. Office of Crystalline Repository Development FY 83 technical project plan

    International Nuclear Information System (INIS)

    1983-03-01

    The technical plan for FY 83 activities of the Office of Crystalline Repository Development is presented in detail. Crystalline Rock Project objectives are discussed in relation to the National Waste Terminal storage (NWTS) program. The plan is in full compliance with requirements mandated by the Nuclear Waste Policy Act of 1982. Implementation will comply with the requirements and criteria set forth in the Nuclear Regulatory Commission regulations (10 CFR 60) and the Environmental Protection Agency standard (40 CFR 191). Technical approaches and the related milestones and schedules are presented for each of the Level 3 NWTS work Breakdown Structure Tasks. These are: Systems, Waste Package, Site, Repository, Regulatory and Institutional, Test Facilities and Excavations, Land Acquisition, and Program Management

  11. Proposed format and content of license applications for deep geologic terminal repositories for radioactive material

    International Nuclear Information System (INIS)

    1978-01-01

    Chapters are devoted to the following: introduction and general description; summary safety analysis; site characteristics; principal design criteria; repository design; operations systems; management of onsite generated waste; radiation protection; accident safety analysis; conduct of operations; operating controls and limits; and quality assurance

  12. Possibility of multiple temperature maxima in geologic repositories for spent fuel from nuclear reactors

    International Nuclear Information System (INIS)

    Beyerlein, S.W.; Claiborne, H.C.

    1980-01-01

    Heat transfer studies show that two temperature maxima at the disposal horizon could be experienced in CANDU spent fuel repositories - one at about 60 years and another slightly higher one at 13,000 years. Because CANDU spent fuels display a monotonically decreasing heat generation rate, it is not immediately obvious why this behavior should occur. This report investigates this behavior, confirms the Canadian results, demonstrates that the double peak phenomenon is due to the presence of the right mixture of short- and long-lived nuclides in the fuel, and concludes that the 13,000-year maximum is largely an artifact of the infinite or very large plane source model. When more realistic repository geometries are used, the second peak disappears for repository sizes less than about 1 km 2 . Over the long term, radial and surface heat transfer causes the thermal history of the disposal region to deviate from that predicted by infinite plane (or large finite) source models by reducing the magnitude of the second peak. Beyond a 1000-year time horizon, care should be exercised in modeling spent fuel repositories to include the proper boundary conditions. For the first few centuries after emplacement, however, the infinite source model is consistent with the finite disk source model as well as with arrays of spherical and point sources. The second temperature peak can be avoided by restricting the size of the repository and/or partitioning out the long-lived components of the fuel. When spent fuel from PWRs was examined for multiple temperature maxima, only one peak was found, even for the infinite plane source model

  13. Developing medical geology in Uruguay: a review.

    Science.gov (United States)

    Mañay, Nelly

    2010-05-01

    Several disciplines like Environmental Toxicology, Epidemiology, Public Health and Geology have been the basis of the development of Medical Geology in Uruguay during the last decade. The knowledge and performance in environmental and health issues have been improved by joining similar aims research teams and experts from different institutions to face environmental problems dealing with the population's exposure to metals and metalloids and their health impacts. Some of the Uruguayan Medical Geology examples are reviewed focusing on their multidisciplinary approach: Lead pollution and exposed children, selenium in critically ill patients, copper deficiency in cattle and arsenic risk assessment in ground water. Future actions are also presented.

  14. Developing Medical Geology in Uruguay: A Review

    Directory of Open Access Journals (Sweden)

    Nelly Mañay

    2010-04-01

    Full Text Available Several disciplines like Environmental Toxicology, Epidemiology, Public Health and Geology have been the basis of the development of Medical Geology in Uruguay during the last decade. The knowledge and performance in environmental and health issues have been improved by joining similar aims research teams and experts from different institutions to face environmental problems dealing with the population’s exposure to metals and metalloids and their health impacts. Some of the Uruguayan Medical Geology examples are reviewed focusing on their multidisciplinary approach: Lead pollution and exposed children, selenium in critically ill patients, copper deficiency in cattle and arsenic risk assessment in ground water. Future actions are also presented.

  15. Evaluation of geological documents available for provisional safety analyses of potential sites for nuclear waste repositories - Are additional geological investigations needed?

    International Nuclear Information System (INIS)

    2010-10-01

    The procedure for selecting repository sites for all categories of radioactive waste in Switzerland is defined in the conceptual part of the Sectoral Plan for Deep Geological Repositories, which foresees a selection of sites in three stages. In Stage I, Nagra proposed geological siting regions based on criteria relating to safety and engineering feasibility. The Swiss Government (the Federal Council) is expected to decide on the siting proposals in 2011. The objective of Stage 2 is to prepare proposals for the location of the surface facilities within the planning perimeters defined by the Federal Council in its decision on Stage 1 and to identify potential sites. Nagra also has to carry out a provisional safety analysis for each site and a safety-based comparison of the sites. Based on this, and taking into account the results of the socio-economic-ecological impact studies, Nagra then has to propose at least two sites for each repository type to be carried through to Stage 3. The proposed sites will then be investigated in more detail in Stage 3 to ensure that the selection of the sites for the General Licence Applications is well founded. In order to realise the objectives of the upcoming Stage 2, the state of knowledge of the geological conditions at the sites has to be sufficient to perform the provisional safety analyses. Therefore, in preparation for Stage 2, the conceptual part of the Sectoral Plan requires Nagra to clarify the need for additional investigations aimed at providing input for the provisional safety analyses. The purpose of the present report is to document Nagra's technical-scientific assessment of this need. The focus is on evaluating the geological information based on processes and parameters that are relevant for safety and engineering feasibility. In evaluating the state of knowledge the key question is whether additional information could lead to a different decision regarding the selection of the sites to be carried through to Stage 3

  16. Long-term observations programme on the geological environment of a radioactive waste repository in clayey or related formations, implications on the various phases of the project

    International Nuclear Information System (INIS)

    Manfroy, P.; Raynal, M.; Bonne, A.

    1993-01-01

    The process of emplacing radioactive waste in deep clayey or related formations involves numerous interdependent actions, the common objective of which is to guarantee optimum isolation of the waste for the durations required. Among these actions, observations on the geological environment will have to extend over a very long period of time, from site characterization to repository closure. All the far-field and near-field observations will constitute the basis and confirmation of the models intended to describe the phenomena which take place in the repository and its surrounding host formation and will have to be taken into account in the repository closure procedures. 6 refs

  17. Radioactive waste disposal programme and siting regions for geological deep repositories. Executive summary. November 2008; Entsorgungsprogramm und Standortgebiete fuer geologische Tiefenlager. Zusammenfassung. November 2008

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-11-15

    There are radioactive wastes in Switzerland. Since many decades they are produced by the operation of the five nuclear power plants, by medicine, industry and research. Important steps towards the disposal of these wastes are already realized; the corresponding activities are practised. This particularly concerns handling and packaging of the radioactive wastes, their characterization and inventory, as well as the interim storage and the inferred transportations. Preparatory works in the field of scientific research on deep geological repositories have allowed to acquire high level of technical and scientific expertise in that domain. The feasibility of building long-term safe geological repositories in Switzerland was demonstrated for all types of radioactive wastes; the demonstration was accepted by the Federal Council. There is enough knowledge to propose geological siting regions for further works. The financial funds already accumulated guaranty the financing of the dismantling of the power plants as well as building deep geological repositories for the radioactive wastes. The regulations already exist and the organisational arrangements necessary for the fruitful continuation of the works already done have been taken. The programme of the disposal of radioactive wastes also describes the next stages towards the timely realization of the deep repositories as well as the level of the financial needs. The programme is updated every five years, checked by the regulatory bodies and accepted by the Federal Council who reports to the parliament. The process of choosing a site, which will be completed in the next years, is detailed in the conceptual part of the programme for deep geological repositories. The NAGRA proposals are based exclusively on technical and scientific considerations; the global evaluation taking into account also political considerations has to be performed by the authorities and the Federal Council. The programme states that at the beginning of

  18. Procedural method for the development of scenarios in the operational phase following closure of final repositories in deep geological formations. Report on the working package 1. Development of the international status of science and technology concerning methods and tools for operational and long-term safety cases; Vorgehensweise bei der Szenarienentwicklung in der Nachverschlussphase von Endlagern in tiefen geologieschen Formationen. Bericht zum Arbeitspaket 1. Weiterentwicklung des internationalen Stands von Wissenschaft und Technik zu Methoden und Werkzeugen fuer Betriebs- und Langzeitsicherheitsnachweise

    Energy Technology Data Exchange (ETDEWEB)

    Uhlmann, Stephan

    2016-09-15

    For the disposal of high-level radioactive wastes the disposal in deep geological formations is internationally favored. The safety cases include the scientific, technical, administrative and operational safety analyses and arguments, including the management system. According to IAEA the safety case includes site qualification, the design of the facility, construction and operation including an accident analysis, the closure phase and the post-closure phase. The safety case includes the evaluation of radiological risks for several scenarios. The report covers the methodology of scenario assumption in the post-closure phase of repositories in deep geological formations.

  19. International Atomic Energy Agency (IAEA) initiatives: Records management for deep and near surface geologic repositories

    International Nuclear Information System (INIS)

    Warner, P.J.

    1996-01-01

    The international scientific community has long had an interest in determining methods by which information regarding nuclear waste repositories, and the inherent danger to humanity, could be passed from generation to generation and society to society. Because nuclear waste will remain radioactive for thousands of years future generations must be warned of the dangers thus eliminating intentional or inadvertent intrusion. Member States of the IAEA have determined that the principle safety of such sites must not rely solely on long term institutional arrangements for the retention of information. It is believed that repository siting, design, operation and postoperation information should be gathered, managed and retained so that this information remains accessible to future societies over a very long period of time. The radionuclide life is 10,000 years; thus the retention of information continues beyond current societies, cultures and languages, and must be continually migrated to new retrieval technologies to assure access

  20. Geology and hydrology of the proposed Lyons, Kansas, radioactive waste repository site. Final report

    International Nuclear Information System (INIS)

    1971-03-01

    The five chapters cover: surface geology and ground-water hydrology, status report of 6-month study of subsurface rocks, study of salt sequence, heat transfer, and energy storage and radiation damage effect in rock salt. 64 figures, 9 tables

  1. 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

  2. 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

  3. Migration of fluids as a tool to evaluate the feasibility of the implantation of geological radioactive wastes repositories (RARN) in granitoid rocks: tests on granites submitted to natural deformation vs. not deformed

    International Nuclear Information System (INIS)

    Lopes, Nilo Henrique Balzani; Barbosa, Pedro Henrique Silva; Santos, Alanna Leite dos; Amorim, Lucas Eustáquio Dias; Freitas, Mônica Elizetti de; Rios, Francisco Javier

    2017-01-01

    Fluid composition and migration studies in granitoid rocks subjected to deformation events are a factor that should be considered in the selection of geologically favorable areas for RANR construction, and may be an excellent complement to engineering barrier designs. The research objective was to develop an academic approach, comparing the behavior of deformed and non-deformed granites, not being related to any CNEN project of deploying repositories. It is concluded that in the choice of suitable sites for the construction of repositories, granite bodies that are submitted to metamorphic / deformation / hydrothermal events or that are very fractured should be disregarded. The domes of granite batholith that have undergone hydraulic billing should also be discarded. It has been found that, because of the warming caused by radioactive decay reactions, there is a real possibility that the release of potentially abrasive fluids contained in the minerals can reach and corrode the walls of the repositories and / or packaging

  4. Seismic stability of the survey areas of potential sites for the deep geological repository of the spent nuclear fuel

    Directory of Open Access Journals (Sweden)

    Kaláb Zdeněk

    2017-07-01

    Full Text Available This paper deals with the seismic stability of the survey areas of potential sites for the deep geological repository of the spent nuclear fuel in the Czech Republic. The basic source of data for historical earthquakes up to 1990 was the seismic website [10]. The most intense earthquake described occurred on September 15, 1590 in the Niederroesterreich region (Austria in the historical period; its reported intensity is Io = 8-9. The source of the contemporary seismic data for the period since 1991 to the end of 2014 was the website [11]. It may be stated based on the databases and literature review that in the period from 1900, no earthquake exceeding magnitude 5.1 originated in the territory of the Czech Republic.

  5. Salt repository sealing materials development program: 5-year work plan

    International Nuclear Information System (INIS)

    Myers, L.B.

    1986-06-01

    This plan covers 5 years (fiscal years 1986 through 1990) of work in the repository sealing materials program to support design decisions and licensing activities for a salt repository. The plan covers a development activity, not a research activity. There are firm deliverables as the end points of each part of the work. The major deliverables are: development plans for code development and materials testing; seal system components models; seal system performance specifications; seal materials specifications; and seal materials properties ''handbook.'' The work described in this plan is divided into three general tasks as follows: mathematical modeling; materials studies (salt, cementitious materials, and earthen materials); and large-scale testing. Each of the sections presents an overview, status, planned activities, and summary of program milestones. This plan will be the starting point for preparing the development plans described above, but is subject to change if preparation of the work plan indicates that a different approach or sequence is preferable to achieve the ultimate goal, i.e., support of design and licensing

  6. Conceptual waste package interim product specifications and data requirements for disposal of glass commercial high-level waste forms in salt geologic repositories

    International Nuclear Information System (INIS)

    1983-10-01

    The conceptual waste package interim product specifications and data requirements presented are applicable to the reference glass composition described in PNL-3838 and carbon steel canister described in ONWI-438. They provide preliminary numerical values for the commercial high-level waste form parameters and properties identified in the waste form performance specification for geologic isolation in salt repositories. Subject areas treated include containment and isolation, operational period safety, criticality control, waste form/production canister identification, and waste package performance testing requirements. This document was generated for use in the development of conceptual waste package designs in salt. It will be revised as additional data, analyses and regulatory requirements become available. 13 references, 1 figure

  7. Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste (Volume 1) Introduction

    International Nuclear Information System (INIS)

    R.A. Levich; J.S. Stuckless

    2006-01-01

    Yucca Mountain in Nevada represents the proposed solution to what has been a lengthy national effort to dispose of high-level radioactive waste, waste which must be isolated from the biosphere for tens of thousands of years. This chapter reviews the background of that national effort and includes some discussion of international work in order to provide a more complete framework for the problem of waste disposal. Other chapters provide the regional geologic setting, the geology of the Yucca Mountain site, the tectonics, and climate (past, present, and future). These last two chapters are integral to prediction of long-term waste isolation

  8. Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste (Volume 1) Introduction

    Energy Technology Data Exchange (ETDEWEB)

    R.A. Levich; J.S. Stuckless

    2006-09-25

    Yucca Mountain in Nevada represents the proposed solution to what has been a lengthy national effort to dispose of high-level radioactive waste, waste which must be isolated from the biosphere for tens of thousands of years. This chapter reviews the background of that national effort and includes some discussion of international work in order to provide a more complete framework for the problem of waste disposal. Other chapters provide the regional geologic setting, the geology of the Yucca Mountain site, the tectonics, and climate (past, present, and future). These last two chapters are integral to prediction of long-term waste isolation.

  9. The United States Polar Rock Repository: A geological resource for the Earth science community

    Science.gov (United States)

    Grunow, Annie M.; Elliot, David H.; Codispoti, Julie E.

    2007-01-01

    The United States Polar Rock Repository (USPRR) is a U. S. national facility designed for the permanent curatorial preservation of rock samples, along with associated materials such as field notes, annotated air photos and maps, raw analytic data, paleomagnetic cores, ground rock and mineral residues, thin sections, and microfossil mounts, microslides and residues from Polar areas. This facility was established by the Office of Polar Programs at the U. S. National Science Foundation (NSF) to minimize redundant sample collecting, and also because the extreme cold and hazardous field conditions make fieldwork costly and difficult. The repository provides, along with an on-line database of sample information, an essential resource for proposal preparation, pilot studies and other sample based research that should make fieldwork more efficient and effective. This latter aspect should reduce the environmental impact of conducting research in sensitive Polar Regions. The USPRR also provides samples for educational outreach. Rock samples may be borrowed for research or educational purposes as well as for museum exhibits.

  10. Evaluation of health and safety impacts of defense high-level waste in geologic repositories

    International Nuclear Information System (INIS)

    Smith, E.D.; Kocher, D.C.; Witherspoon, J.P.

    1985-02-01

    Pursuant to the requirement of the Nuclear Waste Policy Act of 1982 that the President evaluate the use of commercial high-level waste repositories for the disposal of defense high-level wastes, a comparative assessment has been performed of the potential health and safety impacts of disposal of defense wastes in commercial or defense-only repositories. Simplified models were used to make quantitative estimates of both long- and short-term health and safety impacts of several options for defense high-level waste disposal. The results indicate that potential health and safety impacts are not likely to vary significantly among the different disposal options for defense wastes. Estimated long-term health and safety impacts from all defense-waste disposal options are somewhat less than those from commercial waste disposal, while short-term health and safety impacts appear to be insensitive to the differences between defense and commercial wastes. In all cases, potential health and safety impacts are small because of the need to meet stringent standards promulgated by the US Environmental Protection Agency and the US Nuclear Regulatory Commission. We conclude that health and safety impacts should not be a significant factor in the choice of a disposal option for defense high-level wastes. 20 references, 14 tables

  11. Impact of long-term climate change on a deep geological repository for spent nuclear fuel

    International Nuclear Information System (INIS)

    Boulton, G.S.; Kautsky, U.; Moren, L.; Wallroth, T.

    2001-05-01

    The radioactivity of spent nuclear fuel will decay over a period of time (100,000 years or longer) in which we expect major environmental change. Climatically driven changes such as glaciation, permafrost and changes in sea level will affect the subsurface environment and must therefore be considered in performance and safety assessments. We regard the state of climate to be determined by the climate system, comprising the atmosphere, the biosphere, the oceans, the ice sheets and the surface of the lithosphere. Climate can change as a consequence of external forcing or as a consequence of the internal dynamics. The changes in the past show a complex cyclical pattern with repetitive periodicities and magnitudes of change. On the relatively long time scale which is of concern in this report climate changes are believed to be triggered by changes in insolation due to cyclical changes in the earth's orbit around the sun. This is referred to as the Milankovitch theory or the astronomical climate theory. A brief review of our knowledge of the climate system, proxy records and observations of past climate change is presented in the report. The most extreme departures from modern environmental conditions in Sweden have occurred during the cold, glacial cycles with ice sheets covering the whole of Sweden. As part of SKB's palaeohydrogeological research programme a time-dependent, thermo-mechanically coupled model of ice sheet behaviour has been developed in order to simulate past fluctuations of the Scandinavian ice sheet and forecast its future. The ice sheet model can calculate the temperature field and isostatic response of the underlying bedrock, subglacial and proglacial permafrost and the subglacial melt rates. By connecting the glaciation model with hydrogeological and rock mechanical models, the response of the subsurface to climate change can be investigated. In this report the climate-driven environmental changes are represented as a series of successive climate

  12. Impact of long-term climate change on a deep geological repository for spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Boulton, G.S. [Edinburgh Univ. (United Kingdom); Kautsky, U.; Moren, L. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Wallroth, T. [Bergab Consulting Geologists (Sweden)

    2001-05-01

    The radioactivity of spent nuclear fuel will decay over a period of time (100,000 years or longer) in which we expect major environmental change. Climatically driven changes such as glaciation, permafrost and changes in sea level will affect the subsurface environment and must therefore be considered in performance and safety assessments. We regard the state of climate to be determined by the climate system, comprising the atmosphere, the biosphere, the oceans, the ice sheets and the surface of the lithosphere. Climate can change as a consequence of external forcing or as a consequence of the internal dynamics. The changes in the past show a complex cyclical pattern with repetitive periodicities and magnitudes of change. On the relatively long time scale which is of concern in this report climate changes are believed to be triggered by changes in insolation due to cyclical changes in the earth's orbit around the sun. This is referred to as the Milankovitch theory or the astronomical climate theory. A brief review of our knowledge of the climate system, proxy records and observations of past climate change is presented in the report. The most extreme departures from modern environmental conditions in Sweden have occurred during the cold, glacial cycles with ice sheets covering the whole of Sweden. As part of SKB's palaeohydrogeological research programme a time-dependent, thermo-mechanically coupled model of ice sheet behaviour has been developed in order to simulate past fluctuations of the Scandinavian ice sheet and forecast its future. The ice sheet model can calculate the temperature field and isostatic response of the underlying bedrock, subglacial and proglacial permafrost and the subglacial melt rates. By connecting the glaciation model with hydrogeological and rock mechanical models, the response of the subsurface to climate change can be investigated. In this report the climate-driven environmental changes are represented as a series of successive

  13. Draft Environmental Impact Statement for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada

    International Nuclear Information System (INIS)

    1999-01-01

    The Proposed Action addressed in this EIS is to construct, operate and monitor, and eventually close a geologic repository at Yucca Mountain in southern Nevada for the disposal of spent nuclear fuel and high-level radioactive waste currently in storage at 72 commercial and 5 DOE sites across the United States. The EIS evaluates (1) projected impacts on the Yucca Mountain environment of the construction, operation and monitoring, and eventual closure of the geologic repository; (2) the potential long-term impacts of repository disposal of spent nuclear fuel and high-level radioactive waste; (3) the potential impacts of transporting these materials nationally and in the State of Nevada; and (4) the potential impacts of not proceeding with the Proposed Action

  14. Numerical investigation of high level nuclear waste disposal in deep anisotropic geologic repositories

    KAUST Repository

    Salama, Amgad; El Amin, Mohamed F.; Sun, Shuyu

    2015-01-01

    One of the techniques that have been proposed to dispose high level nuclear waste (HLW) has been to bury them in deep geologic formations, which offer relatively enough space to accommodate the large volume of HLW accumulated over the years since

  15. 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.

  16. Expectations, open questions to be addressed in the workshop within the context of a deep geological repository in clay formations

    International Nuclear Information System (INIS)

    Landais, Patrick

    2013-01-01

    Precise knowledge of the clay properties in the various domains concerned by the construction feasibility, the exploitation phase of repository facilities, as well as the long term evolution of the waste and of its environment is of crucial importance in assessing the performance and the safety of the various radioactive waste disposal concepts. The knowledge to be acquired on clays as such goes well beyond solely the field of disposal of radioactive waste. For both, clay formations or bentonites in engineered barriers, the characterization in a continuous way from the nanometer to the micrometer, of their internal structure and the study of the associated physico-chemical phenomena is a fundamental issue. It aims for explaining: The 'Initial state' of the clays, in particular for the clay formations: the nature of the mechanical, hydraulic and geochemical processes, in a broad sense, and the way these processes were involved during the geological history of these formations, The fundamental processes involved by physico-chemical or hydraulic stresses, related to the evolution of the repository at the macroscopic scale. The choice of the characterization scale and relevant modeling is of first importance in the approaches leading to the establishment of the models of representation. Various research works pointed to experimental difficulties in quantifying the microstructure of the clay rocks at scales smaller than a micrometer, because of technical/instrumental limitations. This lack of knowledge at small scales does not allow to fully connect all the Thermal-hydrological-mechanical-chemical (THMC) mechanisms and to integrate them into an up-scaling approach. There already exist conceptual models and experimental approaches to describe the microstructure of argillaceous formations in terms of porosity and texture. Examples on the undisturbed Callovo-Oxfordian (COx) argillite are given in this paper. Questions and objectives to be addressed during the

  17. 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

  18. Devising a groundwater monitoring strategy for a geologic repository for radioactive waste

    International Nuclear Information System (INIS)

    Leonhart, L.S.; DeLuca, F.A.; Sheahan, N.T.; West, L.M.

    1981-01-01

    This paper represents a topical treatment of the subject of groundwater monitoring as it relates to the particular needs of high-level nuclear waste disposal facilities using the Basalt Waste Isolation Project (BWIP) as a specific reference. While the involvement with management of high-level radioactive wastes and the design and operation of repository facilities is presently parochial to the federal government and certain prime contractors, it is believed that the technical aspects involved with this groundwater monitoring example provide an interesting comparison with those encountered at near-surface and underground-injection, hazardous waste disposal operations. In particular, the integration of several program facets ranging from baselining parameters to validation of predictive models into a comprehensive strategy may be of interest. It is hoped that this type of conceptual exchange will be beneficial to all concerned

  19. Multi-barrier system model of the geological repository for spent nuclear fuel

    International Nuclear Information System (INIS)

    Barátová, D.; Necas, V.

    2016-01-01

    The results on the analysis of radionuclide release from the geosphere of hypothetical repository in crystalline rocks are presented. Radionuclides with poor retentive properties (C-14, I-129, Cl-36, Cs-135), represent the largest contribution to the total release rate from the geosphere. A sensitivity analysis of selected geosphere parameters was also performed to evaluate an impact of uncertainties on the total maximum release rate from the geosphere. The results show that the data uncertainty related to the transmissivity distribution of individual transport pathways has the greatest impact on the total maximum release rate from the geosphere. The calculations of release rates were carried out for one disposal container using the simulation software GoldSim. (authors)

  20. The impact of episodic nonequilibrium fracture-matrix flow on geological repository performance

    International Nuclear Information System (INIS)

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

    1991-01-01

    Adequate representation of fracture-matrix interaction during episodic infiltration events is crucial in making valid hydrological predictions of repository performance at Yucca Mountain. Various approximations have been applied to represent fracture-matrix flow interaction, including the Equivalent Continuum Model (ECM), which assumes capillary equilibrium between fractures and matrix, and the Fracture-Matrix Model (FMM), which accounts for nonequilibrium fracture-matrix flow. We analyze the relative impact of matrix imbibition on episodic nonequilibrium fracture-matrix flow for the eight major hydrostratigraphic units in the unsaturated zone at Yucca Mountain. Comparisons are made between ECM and FMM predictions to determine the applicability of the ECM. The implications of nonequilibrium fracture-matrix flow on radionuclide transport are also discussed

  1. WORKSHOP ON DEVELOPMENT OF RADIONUCLIDE GETTERS FOR THE YUCCA MOUNTAIN WASTE REPOSITORY: PROCEEDINGS

    International Nuclear Information System (INIS)

    K.C. Holt

    2006-01-01

    One of the important that the U.S. Department of Energy (DOE) is currently undertaking is the development of a high-level nuclear waste repository to be located at Yucca Mountain, Nevada. Concern is generated by the Yucca Mountain Project (YMP) is due to potential releases as groundwater contamination, as described in the Total System Performance Assessment (TSPA). The dose to an off-site individual using this groundwater for drinking and irrigation is dominated by four radionuclides: Tc-99, I-127, Np-237, and U-238. Ideally, this dose would be limited to a single radionuclide, U-238; in other words, YMP would resemble a uranium ore body, a common geologic feature in the Western U.S. For this reason and because of uncertainties in the behavior of Tc-99, I-127, and Np-237, it would be helpful to limit the amount of Tc, I, and Np leaving the repository, which would greatly increase the confidence in the long-term performance of YMP. An approach to limiting the migration of Tc, I, and Np that is complementary to the existing YMP repository design plans is to employ sequestering agents or ''getters'' for these radionuclides such that their migration is greatly hindered, thus decreasing the amount of radionuclide leaving the repository. Development of such getters presents a number of significant challenges. The getter must have a high affinity and high selectivity for the radionuclide in question since there is approximately a 20- to 50-fold excess of other fission products and a 1000-fold excess of uranium in addition to the ions present in the groundwater. An even greater challenge is that the getters must function over a period greater than the half-life of the radionuclide (greater than 5 half-lives would be ideal). Typically, materials with a high affinity for Tc, I, or Np are not sufficiently durable. For example, strong-base ion exchange resins have a very high affinity for TcO 4 - but are not expected to be durable. On the other hand, durable materials, such as

  2. WORKSHOP ON DEVELOPMENT OF RADIONUCLIDE GETTERS FOR THE YUCCA MOUNTAIN WASTE REPOSITORY

    Energy Technology Data Exchange (ETDEWEB)

    K.C. Holt

    2006-03-13

    One of the important that the U.S. Department of Energy (DOE) is currently undertaking is the development of a high-level nuclear waste repository to be located at Yucca Mountain, Nevada. Concern is generated by the Yucca Mountain Project (YMP) is due to potential releases as groundwater contamination, as described in the Total System Performance Assessment (TSPA). The dose to an off-site individual using this groundwater for drinking and irrigation is dominated by four radionuclides: Tc-99, I-127, Np-237, and U-238. Ideally, this dose would be limited to a single radionuclide, U-238; in other words, YMP would resemble a uranium ore body, a common geologic feature in the Western U.S. For this reason and because of uncertainties in the behavior of Tc-99, I-127, and Np-237, it would be helpful to limit the amount of Tc, I, and Np leaving the repository, which would greatly increase the confidence in the long-term performance of YMP. An approach to limiting the migration of Tc, I, and Np that is complementary to the existing YMP repository design plans is to employ sequestering agents or ''getters'' for these radionuclides such that their migration is greatly hindered, thus decreasing the amount of radionuclide leaving the repository. Development of such getters presents a number of significant challenges. The getter must have a high affinity and high selectivity for the radionuclide in question since there is approximately a 20- to 50-fold excess of other fission products and a 1000-fold excess of uranium in addition to the ions present in the groundwater. An even greater challenge is that the getters must function over a period greater than the half-life of the radionuclide (greater than 5 half-lives would be ideal). Typically, materials with a high affinity for Tc, I, or Np are not sufficiently durable. For example, strong-base ion exchange resins have a very high affinity for TcO{sub 4}{sup -} but are not expected to be durable. On the other

  3. 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

  4. Proceedings of the Workshop on near-field phenomena in geologic repositories for radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    Prediction of the behaviour of radioactive waste and the geologic host medium is a complex problem, involving an understanding of many chemical and physical phenomena. Topics covered by this Workshop include rock mechanics in stressed and heated conditions; thermally induced groundwater flow in fractured rock; chemical changes to rock surfaces associated with groundwater and changes in the thermal and chemical environment; the chemical solubilities and sorption properties of radionuclides; and the long-term integrity of containers and packaging for radioactive waste.

  5. A model for evaluating radiological impacts on organisms other than man for use in post-closure assessments of geological repositories for radioactive wastes.

    Science.gov (United States)

    Thorn, M C; Kelly, M; Rees, J H; Sánchez-Friera, P; Calvez, M

    2002-09-01

    Bioaccumulation and dosimetric models have been developed that allow the computation of dose rates to a wide variety of plants and animals in the context of the deep geological disposal of solid radioactive wastes. These dose rates can be compared with the threshold dose rates at which significant deleterious effects have been observed in field and laboratory observations. This provides a general indication of whether effects on ecosystems could be observable, but does not quantify the level of those effects. To address this latter issue, two indicator organisms were identified and exposure-response relationships were developed for endpoints of potential interest (mortality in conifers and the induction of skeletal malformations in rodents irradiated in utero). The bioaccumulation, dosimetry and exposure-response models were implemented and used to evaluate the potential significance of radionuclide releases from a proposed deep geological repository for radioactive wastes in France. This evaluation was undertaken in the context of a programme of assessment studies being performed by the Agence nationale pour la gestion des déchets radioactifs (ANDRA).

  6. Study of an applicability of technologies developed in the conventional industries from the view point of developing the geological disposal system

    International Nuclear Information System (INIS)

    Ushio, Kazuhiro; Ando, Yasumasa; Kubota, Kazuo; Sokejima, Susumu

    1999-02-01

    The geological disposal study of HLW (High Level Wastes) is being developed in Japan. Especially, JNC has played the central role to proceed this project, while in the industries, from the viewpoint of the environmental measures, various technologies and materials have been developed. Some of them might be applied into the geological disposal. The purpose of this study is to investigate such technologies and their applicability to the geological disposal system. Firstly, the environmental technologies used for the repository of industrial wastes were studied. The concepts of management and the regulations for the repository are summarized, and compared with the current geological disposal concept. Secondly, concerning structural and durable materials, their properties and usage were overviewed and their applicability to the current geological disposal concept was studied. (J.P.N.)

  7. Canada's deep geological repository for used nuclear fuel - update on the site evaluation process and interweaving of aboriginal traditional knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Watts, B.; Belfadhel, M.B.; Facella, J., E-mail: bwatt@nwmo.ca, E-mail: mbenbelfadhel@nwmo.ca, E-mail: jfacella@nwmo.ca [Nuclear Waste Management Organization, Toronto, ON (Canada)

    2015-07-01

    The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management (APM), the approach selected by the Government of Canada for the long-term management of used nuclear fuel generated by Canadian nuclear reactors. The ultimate objective of APM is the centralized containment and isolation of Canada's used nuclear fuel in a Deep Geological Repository (DGR) in a suitable crystalline or sedimentary rock formation. In May 2010, the NWMO initiated a nine-step site selection process to seek an informed and willing community to host Canada's deep geological repository. As of April 2015, twenty-two communities expressed interest in learning more about the project. This paper provides an update on the site evaluation process and describes the approach, methods and criteria used in the assessments, focusing on geological and community well-being studies. Engagement and field activities to interweave Aboriginal Traditional Knowledge with western science are also discussed. (author)

  8. Sandstone uranium deposits of Meghalaya: natural analogues for radionuclide migration and backfill material in geological repository for high level radioactive waste disposal

    International Nuclear Information System (INIS)

    Bajpai, R.K.; Narayan, P.K.

    2008-01-01

    Sandstone uranium deposits serve as potential natural analogue to demonstrate safety offered by geological media against possible release of nuclear waste from their confinement and migration towards biosphere. In this study, available database on geochemical aspects of Domisiat uranium deposit of Meghalaya has been evaluated to highlight the behavior of radionuclides of concern over long term in a geological repository. Constituents like actinides (U and Th), fission products and RE elements are adequately retained in clays and organic matters associated with these sandstone deposits. The study also highlights the possibility of utilization of lean ore discarded during mining and milling as backfill material in far field areas and optimizing near field buffers/backfills in a geological repository located in granitic rocks in depth range of 400-500m. (author)

  9. Rolling Deck to Repository (R2R): Collaborative Development of Linked Data for Oceanographic Research

    Science.gov (United States)

    Arko, Robert; Chandler, Cynthia; Stocks, Karen; Smith, Shawn; Clark, Paul; Shepherd, Adam; Moore, Carla; Beaulieu, Stace

    2013-04-01

    The Rolling Deck to Repository (R2R) program is developing infrastructure to ensure the underway sensor data from U.S. academic oceanographic research vessels are routinely and consistently documented, preserved in long-term archives, and disseminated to the science community. The entire R2R Catalog is published online as a Linked Data collection, making it easily accessible to encourage discovery and integration with data at other repositories. We are developing the R2R Linked Data collection with specific goals in mind: 1.) We facilitate data access and reuse by publishing the richest possible collection of resources to describe vessels, cruises, instruments, and datasets from the U.S. academic fleet, including data quality assessment results and clean trackline navigation; 2.) We facilitate data citation through the entire lifecycle from field acquisition to shoreside archiving to journal articles and global syntheses, by publishing Digital Object Identifiers (DOIs) for datasets and encoding them directly into our Linked Data resources; and 3.) We facilitate federation with other repositories such as the Biological and Chemical Oceanography Data Management Office (BCO-DMO), InterRidge Vents Database, and Index to Marine and Lacustrine Geological Samples (IMLGS), by reciprocal linking between RDF resources and supporting the RDF Query Language. R2R participates in the Ocean Data Interoperability Platform (ODIP), a joint European-U.S.-Australian partnership to facilitate the sharing of data and documentation across international borders. We publish our controlled vocabularies as a Simple Knowledge Organization System (SKOS) concept collection, and are working toward alignment with SeaDataNet and other community-standard terms using the NERC Vocabulary Server (NVS). http://rvdata.us/

  10. Rock grouting. Current competence and development for the final repository

    International Nuclear Information System (INIS)

    Emmelin, Ann; Brantberger, Martin; Eriksson, Magnus; Gustafson, Gunnar; St ille, Haakan

    2007-06-01

    The report aims at presenting the overall state of grouting competence and development relating to the final repository and at motivating and giving detail to the grouting sections presented in the 2007 version of the overall SKB report 'Programme for research, development and demonstration of methods for the management and disposal of nuclear waste' that is presented to the government every three years. The report offers suggestions for principles for planning, design and execution of grouting and describes the further work thought to be necessary in order to meet the requirements of the final repository, that are currently given as working premises. This report does not aim to, and cannot, describe the grouting processes in detail. For details of current concepts, experience and development work, a list of references is provided. In Chapter 2, the task of sealing the underground repository is examined and an overall approach presented. Although the requirements related to this task are preliminary, it is made evident that they concern both the actual grouting results and the process leading to the achievement of these results. Chapter 3 is a conceptual description of grouting and the factors that govern the spreading of grout in the rock mass. It is intended as an introduction to Chapters 4-6, which describe the state of grouting competence and the tools available for the sealing of the final repository facility. Both common practice and cutting-edge research are dealt with in these chapters, mainly relying on references where available. Chapters 4 and 5 focus on the system consisting of the fundamental components the rock mass, the grout materials and the grouting technology, and how these system components interact whilst, in Chapter 6, the rock/grout technical system is viewed in a brief organizational context. Based on the requirements on results and the overall grouting process on the one hand and the current competence in grouting theory and practice on the

  11. Rock grouting. Current competence and development for the final repository

    Energy Technology Data Exchange (ETDEWEB)

    Emmelin, Ann (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE)); Brantberger, Martin (Ramboell (SE)); Eriksson, Magnus (Vattenfall Power Consultant (SE)); Gustafson, Gunnar (Chalmers Univ. of Technology, Goeteborg (SE)); Stille, Haakan (Royal Inst. of Technology, Stockholm (SE))

    2007-06-15

    The report aims at presenting the overall state of grouting competence and development relating to the final repository and at motivating and giving detail to the grouting sections presented in the 2007 version of the overall SKB report 'Programme for research, development and demonstration of methods for the management and disposal of nuclear waste' that is presented to the government every three years. The report offers suggestions for principles for planning, design and execution of grouting and describes the further work thought to be necessary in order to meet the requirements of the final repository, that are currently given as working premises. This report does not aim to, and cannot, describe the grouting processes in detail. For details of current concepts, experience and development work, a list of references is provided. In Chapter 2, the task of sealing the underground repository is examined and an overall approach presented. Although the requirements related to this task are preliminary, it is made evident that they concern both the actual grouting results and the process leading to the achievement of these results. Chapter 3 is a conceptual description of grouting and the factors that govern the spreading of grout in the rock mass. It is intended as an introduction to Chapters 4-6, which describe the state of grouting competence and the tools available for the sealing of the final repository facility. Both common practice and cutting-edge research are dealt with in these chapters, mainly relying on references where available. Chapters 4 and 5 focus on the system consisting of the fundamental components the rock mass, the grout materials and the grouting technology, and how these system components interact whilst, in Chapter 6, the rock/grout technical system is viewed in a brief organizational context. Based on the requirements on results and the overall grouting process on the one hand and the current competence in grouting theory and

  12. Local Communities' Expectations and Demands on Monitoring and the Preservation of Records, Knowledge and Memory of a Deep Geological Repository

    International Nuclear Information System (INIS)

    2014-01-01

    This report explores the role, needs and expectations of local communities regarding monitoring and RK and M preservation of radioactive waste management facilities, in particular deep geological repositories. It was developed through both field and desk research. A questionnaire survey to FSC members was undertaken in July and August 2012, followed by interviews with a broad range of involved stakeholders. A brief update survey in August and September 2013 gathered replies from a subset of countries. A literature review was carried out, focusing on FSC publications and other documents and publications found through internet or suggested by interviewees. After a brief presentation of the study rationale and methodology in section 1, section 2 reviews the FSC literature on aspects related to RK and M and monitoring. In section 3 the report identifies concerns and expectations of local communities regarding monitoring in the different phases of the repository life cycle and in the different national contexts, according to the results gathered from the survey and interviews undertaken as part of this project. The fourth section discusses how RK and M preservation may emerge as a subject of debate with local stakeholders in different countries in the years to come. Section 5 recognises that monitoring and RK and M preservation potentially serve to build and maintain confidence in the long-term safety of deep geological repositories. Finally, the concept of oversight is considered in section 6 as a term that embraces monitoring and RK and M, and its interpretation in different reports is illustrated. Final reflections, with some conclusions, are provided in section 7. Four appendixes are offered. Appendix I summarises in a table the design features of a radioactive waste management facility that may help the memory of the site to be preserved over generations, as suggested in NEA (2007). Appendix II reports statements related with monitoring and RK and M preservation in

  13. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 16. Repository preconceptual design studies: BPNL waste forms in salt

    International Nuclear Information System (INIS)

    1978-04-01

    This volume, Volume 16, ''Repository Preconceptual Design Studies: BPNL Waste Forms in Salt,'' is one of a 23 volume series, ''Technical Support for GEIS: Radioactive Waste Isolation in Geologic Formations,'' Y/OWI/TM-36, which supplements the ''Contribution to Draft Generic Environmental Impact Statement on Commercial Waste Management: Radioactive Waste Isolation in Geologic Formations,'' Y/OWI/TM-44. The series provide a more complete technical basis for the preconceptual designs, resource requirements, and environmental source terms associated with isolating commercial LWR wastes in underground repositories in salt, granite, shale and basalt. Wastes are considered from three fuel cycles: uranium and plutonium recycling, no recycling of spent fuel and uranium-only recycling. This document describes a preconceptual design for a nuclear waste storage facility in salt. The waste forms assumed to arrive at the repository were supplied by Battelle Pacific Northwest Laboratories (BPNL). The facility design consists of several chambers excavated deep within a geologic formation together with access shafts and supportive surface structures. The facility design provides for: receiving and unloading waste containers; lowering them down shafts to the mine level; transporting them to the proper storage area and emplacing them in mined storage rooms. Drawings of the facility design are contained in TM-36/17, ''Drawings for Repository Preconceptual Design Studies: BPNL Waste Forms in Salt.''

  14. Status and future developments of risk analysis for repositories of radioactive wastes in salt formations in the Federal Republic of Germany

    International Nuclear Information System (INIS)

    Proske, R.

    1977-01-01

    In the Federal Republic of Germany a hypothetical repository for High-Level Radioactive Waste in a salt formation was taken as basis for a first attempt to use the methodology of risk analysis in order to get statements on the safety of such a geologic and mining system. Several institutions were engaged in drawing up fault trees, development of release models and calculation of the risk. A lot of R+D-work is scheduled to be carried out in future which includes optimization of the application of risk analysis methodology to geologic and mining systems, further development of release models, development of a model describing the migration of radionuclides in typical geologic strata and soils of the Federal Republic of Germany and application of risk analysis methodology to different repositories and disposal technologies

  15. Coupled Multi-physical Simulations for the Assessment of Nuclear Waste Repository Concepts: Modeling, Software Development and Simulation

    Science.gov (United States)

    Massmann, J.; Nagel, T.; Bilke, L.; Böttcher, N.; Heusermann, S.; Fischer, T.; Kumar, V.; Schäfers, A.; Shao, H.; Vogel, P.; Wang, W.; Watanabe, N.; Ziefle, G.; Kolditz, O.

    2016-12-01

    As part of the German site selection process for a high-level nuclear waste repository, different repository concepts in the geological candidate formations rock salt, clay stone and crystalline rock are being discussed. An open assessment of these concepts using numerical simulations requires physical models capturing the individual particularities of each rock type and associated geotechnical barrier concept to a comparable level of sophistication. In a joint work group of the Helmholtz Centre for Environmental Research (UFZ) and the German Federal Institute for Geosciences and Natural Resources (BGR), scientists of the UFZ are developing and implementing multiphysical process models while BGR scientists apply them to large scale analyses. The advances in simulation methods for waste repositories are incorporated into the open-source code OpenGeoSys. Here, recent application-driven progress in this context is highlighted. A robust implementation of visco-plasticity with temperature-dependent properties into a framework for the thermo-mechanical analysis of rock salt will be shown. The model enables the simulation of heat transport along with its consequences on the elastic response as well as on primary and secondary creep or the occurrence of dilatancy in the repository near field. Transverse isotropy, non-isothermal hydraulic processes and their coupling to mechanical stresses are taken into account for the analysis of repositories in clay stone. These processes are also considered in the near field analyses of engineered barrier systems, including the swelling/shrinkage of the bentonite material. The temperature-dependent saturation evolution around the heat-emitting waste container is described by different multiphase flow formulations. For all mentioned applications, we illustrate the workflow from model development and implementation, over verification and validation, to repository-scale application simulations using methods of high performance computing.

  16. A Bayesian reliability approach to the performance assessment of a geological waste repository

    International Nuclear Information System (INIS)

    Flueck, J.A.; Singh, A.K.

    1992-01-01

    This paper discusses the task of selecting a suitable site for a high-level waste disposal repository (HLWR) which certainly is a complex one in that one must address both engineering and economic factors of the proposed facility and site as well as environmental, public health, safety, and sociopolitical factors. Acknowledging the complexity of the siting problem for a HLWR leads one to readily conclude that a formal analysis, including the use of a performance assessment model (PAM), is needed to assist the designated decision makers in their task of selecting a suitable site. The overall goal of a PAM is to aid the decision makers in making the best possible technical siting decision. For a number of reason, the authors believe that the combining of both Bayesian decision theory and reliability methodology provides the best approach to constructing a useful PAM for assisting in the siting of a HLWR. This combination allows one to formally integrate existing relevant information, professional judgement, and component model outputs to produce conditionally estimated probabilities for a decision tree approach to the radionuclide release problem of a proposed HLWR. If loss functions are available, this also allows one to calculate the expected costs or losses from possible radionuclide releases. This latter calculation may be very important in selecting the final site from among a number of alternative sites

  17. Grain size and burnup dependence of spent fuel oxidation: Geological repository impact

    International Nuclear Information System (INIS)

    Kansa, E.J.; Hanson