WorldWideScience

Sample records for nuclear fuel disposal

  1. Nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Merrett, G.J.; Gillespie, P.A.

    1983-07-01

    This report discusses events and processes that could adversely affect the long-term stability of a nuclear fuel waste disposal vault or the regions of the geosphere and the biosphere to which radionuclides might migrate from such a vault

  2. Nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Allan, C.J.

    1993-01-01

    The Canadian concept for nuclear fuel waste disposal is based on disposing of the waste in a vault excavated 500-1000 m deep in intrusive igneous rock of the Canadian Shield. The author believes that, if the concept is accepted following review by a federal environmental assessment panel (probably in 1995), then it is important that implementation should begin without delay. His reasons are listed under the following headings: Environmental leadership and reducing the burden on future generations; Fostering public confidence in nuclear energy; Forestalling inaction by default; Preserving the knowledge base. Although disposal of reprocessing waste is a possible future alternative option, it will still almost certainly include a requirement for geologic disposal

  3. Nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    1982-01-01

    This film for a general audience deals with nuclear fuel waste management in Canada, where research is concentrating on land based geologic disposal of wastes rather than on reprocessing of fuel. The waste management programme is based on cooperation of the AECL, various universities and Ontario Hydro. Findings of research institutes in other countries are taken into account as well. The long-term effects of buried radioactive wastes on humans (ground water, food chain etc.) are carefully studied with the help of computer models. Animated sequences illustrate the behaviour of radionuclides and explain the idea of a multiple barrier system to minimize the danger of radiation hazards

  4. Disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    1979-12-01

    This report addresses the topic of the mined geologic disposal of spent nuclear fuel from Pressurized Water Reactors (PWR) and Boiling Water Reactors (BWR). Although some fuel processing options are identified, most of the information in this report relates to the isolation of spent fuel in the form it is removed from the reactor. The characteristics of the waste management system and research which relate to spent fuel isolation are discussed. The differences between spent fuel and processed HLW which impact the waste isolation system are defined and evaluated for the nature and extent of that impact. What is known and what needs to be determined about spent fuel as a waste form to design a viable waste isolation system is presented. Other waste forms and programs such as geologic exploration, site characterization and licensing which are generic to all waste forms are also discussed. R and D is being carried out to establish the technical information to develop the methods used for disposal of spent fuel. All evidence to date indicates that there is no reason, based on safety considerations, that spent fuel should not be disposed of as a waste

  5. Spent nuclear fuel disposal liability insurance

    International Nuclear Information System (INIS)

    Martin, D.W.

    1984-01-01

    This thesis examines the social efficiency of nuclear power when the risks of accidental releases of spent fuel radionuclides from a spent fuel disposal facility are considered. The analysis consists of two major parts. First, a theoretical economic model of the use of nuclear power including the risks associated with releases of radionuclides from a disposal facility is developed. Second, the costs of nuclear power, including the risks associated with a radionuclide release, are empirically compared to the costs of fossil fuel-fired generation of electricity. Under the provisions of the Nuclear Waste Policy Act of 1982, the federally owned and operated spent nuclear fuel disposal facility is not required to maintain a reserve fund to cover damages from an accidental radionuclide release. Thus, the risks of a harmful radionuclide release are not included in the spent nuclear fuel disposal fee charged to the electric utilities. Since the electric utilities do not pay the full, social costs of spent fuel disposal, they use nuclear fuel in excess of the social optimum. An insurance mechanism is proposed to internalize the risks associated with spent fueled disposal. Under this proposal, the Federal government is required to insure the disposal facility against any liabilities arising from accidental releases of spent fuel radionuclides

  6. Alternatives for nuclear fuel disposal

    International Nuclear Information System (INIS)

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

    2010-10-01

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

  7. Nuclear fuel waste disposal in Canada

    International Nuclear Information System (INIS)

    Dormuth, K.W.; Gillespie, P.A.

    1990-05-01

    Atomic Energy of Canada Limited (AECL) has developed a concept for disposing of Canada's nuclear fuel waste and is submitting it for review under Federal Environmental Assessment and Review Process. During this review, AECL intends to show that careful, controlled burial 500 to 1000 metres deep in plutonic rock of the Canadian Precambrian Shield is a safe and feasible way to dispose of Canada's nuclear fuel waste. The concept has been assessed without identifying or evaluating any particular site for disposal. AECL is now preparing a comprehensive report based on more than 10 years of research and development

  8. Nuclear fuel waste disposal in Canada

    International Nuclear Information System (INIS)

    Dormuth, K.W.; Gillespie, P.A.

    1990-05-01

    Atomic Energy of Canada Limited (AECL) has developed a concept for disposing of Canada's nuclear fuel waste and is submitting it for review under the Federal Environmental Assessment and Review Process. During this review, AECL intends to show that careful, controlled burial 500 to 1000 metres deep in plutonic rock of the Canadian Precambrian Shield is a safe and feasible way to dispose of Canada's nuclear fuel waste. The concept has been assessed without identifying or evaluating any particular site for disposal. AECL is now preparing a comprehensive report based on more than 10 years of research and development

  9. Disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    Dormuth, K.W.; Nuttall, K.

    1994-01-01

    In 1978, the governments of Canada and Ontario established the Nuclear Fuel Waste Management program. As of the time of the conference, the research performed by AECL was jointly funded by AECL and Ontario Hydro through the CANDU owners' group. Ontario Hydro have also done some of the research on disposal containers and vault seals. From 1978 to 1992, AECL's research and development on disposal cost about C$413 million, of which C$305 was from funds provided to AECL by the federal government, and C$77 million was from Ontario Hydro. The concept involves the construction of a waste vault 500 to 1000 metres deep in plutonic rock of the Canadian Precambrian Shield. Used fuel (or possibly solidified reprocessing waste) would be sealed into containers (of copper, titanium or special steel) and emplaced (probably in boreholes) in the vault floor, surrounded by sealing material (buffer). Disposal rooms might be excavated on more than one level. Eventually all excavated openings in the rock would be backfilled and sealed. Research is organized under the following headings: disposal container, waste form, vault seals, geosphere, surface environment, total system, assessment of environmental effects. A federal Environmental Assessment Panel is assessing the concept (holding public hearings for the purpose) and will eventually make recommendations to assist the governments of Canada and Ontario in deciding whether to accept the concept, and how to manage nuclear fuel waste. 16 refs., 1 tab., 3 figs

  10. The chemistry of nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Wiles, D.R.

    2002-01-01

    About one-fifth of the world's supply of energy is derived from nuclear fission. While this important source of power avoids the environmental and resource problems of most other fuels, and although nuclear accident statistics are much less alarming, no other peacetime technology has evoked such public disquiet and impassioned feeling. Central to dealing with these fears is the management and disposal of radioactive waste. An expert Canadian panel in 1977 recommended permanent disposal of wastes in deep geological formations, providing a basis for subsequent policies and research. In 1988, the Federal Environmental Assessment Review Office (FEARO) appointed a panel to assess the proposed disposal concepts and to recommend government policy. The panel in turn appointed a Scientific Review Group to examine the underlying science. Behind all these issues lay one central question: How well is the chemistry understood? This became the principal concern of Professor Donald Wiles, the senior nuclear chemist of the Scientific Review Group. In this book, Dr. Wiles carefully describes the nature of radioactivity and of nuclear power and discusses in detail the management of radioactive waste by the multi-barrier system, but also takes an unusual approach to assessing the risks. Using knowledge of the chemical properties of the various radionuclides in spent fuel, this book follows each of the important radionuclides as it travels through the many barriers placed in its path. It turns out that only two radionuclides are able to reach the biosphere, and they arrive at the earth's surface only after many thousands of years. A careful analysis of the critical points of the disposal plan emphasizes site rejection criteria and other stages at which particular care must be taken, demonstrating how dangers can be anticipated and putting to rest the fear of nuclear fuel waste and its geological burial

  11. Nuclear fuel waste disposal. Canada's consultative approach

    Energy Technology Data Exchange (ETDEWEB)

    Hillier, J A.R.; Dixon, R S [AECL (Canada)

    1993-07-01

    Over the past two decades, society has increasingly demanded more public participation and public input into decision-making by governments. Development of the Canadian concept for deep geological disposal of used nuclear fuel has proceeded in a manner that has taken account of the requirements for social acceptability as well as technical excellence. As the agency responsible for development of the disposal concept, Atomic Energy of Canada Limited (AECL) has devoted considerable effort to consultation with the various publics that have an interest in the concept. This evolutionary interactive and consultative process, which has been underway for some 14 years, has attempted to keep the public informed of the technical development of the concept and to invite feedback. This paper describes the major elements of this evolutionary process, which will continue throughout the concept assessment and review process currently in progress. (author)

  12. Nuclear fuel waste disposal. Canada's consultative approach

    International Nuclear Information System (INIS)

    Hillier, J.A.R.; Dixon, R.S.

    1993-01-01

    Over the past two decades, society has increasingly demanded more public participation and public input into decision-making by governments. Development of the Canadian concept for deep geological disposal of used nuclear fuel has proceeded in a manner that has taken account of the requirements for social acceptability as well as technical excellence. As the agency responsible for development of the disposal concept, Atomic Energy of Canada Limited (AECL) has devoted considerable effort to consultation with the various publics that have an interest in the concept. This evolutionary interactive and consultative process, which has been underway for some 14 years, has attempted to keep the public informed of the technical development of the concept and to invite feedback. This paper describes the major elements of this evolutionary process, which will continue throughout the concept assessment and review process currently in progress. (author)

  13. Monitoring methods for nuclear fuel waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, R B; Barnard, J W; Bird, G A [and others

    1997-11-01

    This report examines a variety of monitoring activities that would likely be involved in a nuclear fuel waste disposal project, during the various stages of its implementation. These activities would include geosphere, environmental, vault performance, radiological, safeguards, security and community socioeconomic and health monitoring. Geosphere monitoring would begin in the siting stage and would continue at least until the closure stage. It would include monitoring of regional and local seismic activity, and monitoring of physical, chemical and microbiological properties of groundwater in rock and overburden around and in the vault. Environmental monitoring would also begin in the siting stage, focusing initially on baseline studies of plants, animals, soil and meteorology, and later concentrating on monitoring for changes from these benchmarks in subsequent stages. Sampling designs would be developed to detect changes in levels of contaminants in biota, water and air, soil and sediments at and around the disposal facility. Vault performance monitoring would include monitoring of stress and deformation in the rock hosting the disposal vault, with particular emphasis on fracture propagation and dilation in the zone of damaged rock surrounding excavations. A vault component test area would allow long-term observation of containers in an environment similar to the working vault, providing information on container corrosion mechanisms and rates, and the physical, chemical and thermal performance of the surrounding sealing materials and rock. During the operation stage, radiological monitoring would focus on protecting workers from radiation fields and loose contamination, which could be inhaled or ingested. Operational zones would be established to delineate specific hazards to workers, and movement of personnel and materials between zones would be monitored with radiation detectors. External exposures to radiation fields would be monitored with dosimeters worn by

  14. A disposal centre for irradiated nuclear fuel: conceptual design study

    International Nuclear Information System (INIS)

    1980-09-01

    This report describes a conceptual design of a disposal centre for irradiated nuclear fuel. The surface facilities consist of plants for the preparation of steel cylinders containing irradiated nuclear fuel immobilized in lead, shaft headframe buildings, and all necessary support facilities. The undergound disposal vault is located on one level at a depth of 1000 metres. The cylinders containing the irradiated fuel are emplaced on a one-metre thick layer of backfill material and then completely covered with backfill. All surface and subsurface facilities are described, operations and schedules are summarized, and cost estimates and manpower requirements are given. (auth)

  15. Status of US program for disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Smith, R.I.

    1991-04-01

    In this paper, a brief history of the United States' program for the disposal of spent nuclear fuel (SNF) and the legislative acts that have guided the program are discussed. The current plans and schedules for beginning acceptance of SNF from the nuclear utilities for disposal are described, and some of the development activities supporting the program are discussed. And finally, the viability of the SNF disposal fee presently paid into the Nuclear Waste Fund by the owners/generators of commercial SNF and high-level waste (HLW) is examined. 12 refs., 9 figs

  16. Management and disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    1987-05-01

    The programme consists of the long-term and short-term programme, the continued bedrock investigations, the underground research laboratory, the decision-making procedure in the site selection process and information questions during the site selection process. The National Board for Spent Nuclear Fuel hereby subunits both the SKB's R and D Programme 86 and the Board's statement concerning the programme. Decisions in the matter have been made by the Board's executive committee. (DG)

  17. Management and disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    1987-05-01

    The National Board for Spent Nuclear Fuel, in submitting its statement of comment to the Government on the Swedish Nuclear Fuel and Waste Management Company's (Svensk Kaernbraenslehantering AB, SKB) research programme, R and D Programme 86, has also put forward recommendations on the decision-making procedure and on the question of public information during the site selection process. In summary the Board proposes: * that the Government instruct the National Board for Spent Nuclear Fuel to issue certain directives concerning additions to and changes in R and D Programme 86, * that the Board's views on the decision-making procedure in the site selection process be taken into account in the Government's review of the so-called municipal veto in accordance with Chapter 4, Section 3 of the Act (1987:12) on the conservation of natural resources etc., NRL, * that the Board's views on the decision-making procedure and information questions during the site selection process serve as a basis for the continued work. Three appendices are added to the report: 1. Swedish review statements (SV), 2. International Reviews, 3. Report from the site selection group (SV)

  18. Final disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Thoregren, U.

    1983-04-01

    Like many other countries whith similar geological conditions, Sweden plans to dispose of its long-lived radioactive nuclear waste by depositing it in final repositories located deep down in the crystalline bedrock. In order to be able to demonstrate that a given rock formation is suited for waste storage, it is necessary to have knowledge concerning its properties, particularly those that determine groundwater conditions and chemistry within the area. Also of importance are data that shed light on rock mechanics in the area and the occurrence of valuable minerals. The SKBF/KBS programme includes plans to carry out geological studies of 10-15 areas in different parts of the country during the 1980s. A standard programme for these studies is described in the following. The standard programme is inteded to serve as a basis for planning of the work and revisions or modifications that may be found to be appropriate in view of local conditions or experience. (author)

  19. The disposal of Canada's nuclear fuel waste: engineering for a disposal facility

    International Nuclear Information System (INIS)

    Simmons, G.R.; Baumgartner, P.

    1994-01-01

    This report presents some general considerations for engineering a nuclear fuel waste disposal facility, alternative disposal-vault concepts and arrangements, and a conceptual design of a used-fuel disposal centre that was used to assess the technical feasibility, costs and potential effects of disposal. The general considerations and alternative disposal-vault arrangements are presented to show that options are available to allow the design to be adapted to actual site conditions. The conceptual design for a used-fuel disposal centre includes descriptions of the two major components of the disposal facility, the Used-Fuel Packaging Plant and the disposal vault; the ancillary facilities and services needed to carry out the operations are also identified. The development of the disposal facility, its operation, its decommissioning, and the reclamation of the site are discussed. The costs, labour requirements and schedules used to assess socioeconomic effects and that may be used to assess the cost burden of waste disposal to the consumer of nuclear energy are estimated. The Canadian Nuclear Fuel Waste Management Program is funded jointly by AECL and Ontario Hydro under the auspices of the CANDU Owners Group. (author)

  20. Final disposal of high levels waste and spent nuclear fuel

    International Nuclear Information System (INIS)

    Gelin, R.

    1984-05-01

    Foreign and international activities on the final disposal of high-level waste and spent nuclear fuel have been reviewed. A considerable research effort is devoted to development of acceptable disposal options. The different technical concepts presently under study are described in the report. Numerous studies have been made in many countries of the potential risks to future generations from radioactive wastes in underground disposal repositories. In the report the safety assessment studies and existing performance criteria for geological disposal are briefly discussed. The studies that are being made in Canada, the United States, France and Switzerland are the most interesting for Sweden as these countries also are considering disposal into crystalline rocks. The overall time-tables in different countries for realisation of the final disposal are rather similar. Normally actual large-scale disposal operations for high-level wastes are not foreseen until after year 2000. In the United States the Congress recently passed the important Nuclear Waste Policy Act. It gives a rather firm timetable for site-selection and construction of nuclear waste disposal facilities. According to this act the first repository for disposal of commercial high-level waste must be in operation not later than in January 1998. (Author)

  1. Disposal of spent nuclear fuel from NPP Krsko

    International Nuclear Information System (INIS)

    Mele, I.

    2004-01-01

    In order to get a clear view of the future liabilities of Slovenia and Croatia regarding the long term management of radioactive waste and spent nuclear fuel produced by the NPP Krsko, an estimation of disposal cost for low and intermediate level waste (LILW) as well as for spent nuclear fuel is needed. This cost estimation represents the basis for defining the target value for the financial resources to be accrued by the two national decommissioning and waste disposal funds, as determined in the agreement between Slovenia and Croatia on the ownership and exploitation of the NPP Krsko from March 2003, and for specifying their financial strategies. The one and only record of the NPP Krsko spent fuel disposal costs was made in the NPP Krsko Decommissioning Plan from 1996 [1]. As a result of incomplete input data, the above SF disposal cost estimate does not incorporate all cost elements. A new cost estimation was required in the process of preparation of the Joint Decommissioning and Waste Management Programme according to the provisions of the above mentioned agreement between Slovenia and Croatia. The basic presumptions and reference scenario for the disposal of spent nuclear fuel on which the cost estimation is based, as well as the applied methodology and results of cost estimation, are presented in this paper. Alternatives to the reference scenario and open questions which need to be resolved before the relevant final decision is taken, are also briefly discussed. (author)

  2. The final disposal facility of spent nuclear fuel

    International Nuclear Information System (INIS)

    Prvakova, S.; Necas, V.

    2001-01-01

    Today the most serious problem in the area of nuclear power engineering is the management of spent nuclear fuel. Due to its very high radioactivity the nuclear waste must be isolated from the environment. The perspective solution of nuclear fuel cycle is the final disposal into geological formations. Today there is no disposal facility all over the world. There are only underground research laboratories in the well developed countries like the USA, France, Japan, Germany, Sweden, Switzerland and Belgium. From the economical point of view the most suitable appears to build a few international repositories. According to the political and social aspect each of the country prepare his own project of the deep repository. The status of those programmes in different countries is described. The development of methods for the long-term management of radioactive waste is necessity in all countries that have had nuclear programmes. (authors)

  3. Disposal of spent fuel from German nuclear power plants - 16028

    International Nuclear Information System (INIS)

    Graf, Reinhold; Brammer, Klaus-Juergen; Filbert, Wolfgang; Bollingerfehr, Wilhelm

    2009-01-01

    The 'direct disposal of spent fuel' as a part of the current German reference concept was developed as an alternative to spent fuel reprocessing and vitrified HLW disposal. The technical facilities necessary for the implementation of this part of the reference concept, the so called POLLUX R concept, i.e. interim storage buildings for casks containing spent fuel, a pilot conditioning facility, and a special cask 'POLLUX' for final disposal have been built. With view to a geological salt formation all handling procedures for the direct disposal of spent fuel were tested aboveground in full-scale test facilities. To optimise the reference concept, all operational steps have been reviewed for possible improvements. The two additional concepts for the direct disposal of SF are the BSK 3 concept and the DIREGT concept. Both concepts rely on borehole emplacement technology, vertical boreholes for the BSK 3 concept und horizontal boreholes for the DIREGT concept. Supported by the EU and the German Federal Ministry of Economics and Technology (BMWi), DBE TECHNOLOGY built an aboveground full-scale test facility to simulate all relevant handling procedures for the BSK 3 disposal concept. GNS (Company for Nuclear Service), representing the German utilities, provided the main components and its know-how concerning cask design and manufacturing. The test program was concluded recently after more than 1.000 emplacement operations had been performed successfully. The BSK 3 emplacement system in total comprises an emplacement device, a borehole lock, a transport cart, a transfer cask which will shuttle between the aboveground conditioning facility and the underground repository, and the BSK 3 canister itself, designed to contain the fuel rods of three PWR-fuel assemblies with a total of about 1.6 tHM. The BSK 3 concept simplifies the operation of the repository because the handling procedures and techniques can also be applied for the disposal of reprocessing residues. In addition

  4. Education - path towards solution regarding disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Klein, D.E.

    1991-01-01

    Education, not emotional reaction, is the path to take in the safe disposal of spent nuclear fuel. Education is needed at all levels: Elementary schools, secondary schools, two-year colleges, four-year colleges, graduate schools, and adult education. The Office of Civilian Radioactive Waste Management (OCRWM) should not be expected to tackle this problem alone. Assistance is needed from local communities, schools, and state and federal governments. However, OCRWM can lay the foundation for a comprehensive educational plan directed specifically at educating the public on the spent nuclear fuel issue and OCRWM can begin the implementation of this plan

  5. Pyroprocessing oxide spent nuclear fuels for efficient disposal

    International Nuclear Information System (INIS)

    McPheeters, C.C.; Pierce, R.D.; Mulcahey, T.P.

    1994-01-01

    Pyrochemical processing as a means for conditioning spent nuclear fuels for disposal offers significant advantages over the direct disposal option. The advantages include reduction in high-level waste volume; conversion of most of the high-level waste to a low-level waste in which nearly all the transuranics (TRU) have been removed; and incorporation of the TRUs into a stable, highly radioactive waste form suitable for interim storage, ultimate destruction, or repository disposal. The lithium process has been under development at Argonne National Laboratory for use in pyrochemical conditioning of spent fuel for disposal. All of the process steps have been demonstrated in small-scale (0.5-kg simulated spent fuel) experiments. Engineering-scale (20-kg simulated spent fuel) demonstration of the process is underway, and small-scale experiments have been conducted with actual spent fuel from a light water reactor (LWR). The lithium process is simple, operates at relatively low temperatures, and can achieve high decontamination factors for the TRU elements. Ordinary materials, such as carbon steel, can be used for process containment

  6. Design report of the canister for nuclear fuel disposal

    International Nuclear Information System (INIS)

    Raiko, H.; Salo, J.P.

    1996-12-01

    The report provides a summary of the design of the canister for final disposal of nuclear fuel. The canister structure consists of a cylindrical massive nodular graphite cast iron insert covered by a 50 mm thick copper overlay. The capacity of the canister is 11 assemblies of BWR or VVER 440 fuel. The canister shall be tight with a high probability for about 100 000 years. The design basis of the canister is set, the performed analyses are summarised and the results are assessed and discussed in the report. (26 refs.)

  7. Uncanistered Spent Nuclear fuel Disposal Container System Description Document

    International Nuclear Information System (INIS)

    Pettit, N. E.

    2001-01-01

    The Uncanistered Spent Nuclear Fuel (SNF) Disposal Container System supports the confinement and isolation of waste within the Engineered Barrier System of the Monitored Geologic Repository (MGR). Disposal containers are loaded with intact uncanistered assemblies and/or individually canistered SNF assemblies and sealed in the surface waste handling facilities, transferred to the underground through the access drifts, and emplaced in emplacement drifts. The Uncanistered SNF Disposal Container provides long-term confinement of the commercial SNF placed inside, and withstands the loading, transfer, emplacement, and retrieval loads and environments. The Uncanistered SNF Disposal Container System provides containment of waste for a designated period of time, and limits radionuclide release. The disposal container maintains the waste in a designated configuration, withstands maximum handling and rockfall loads, limits the individual SNF assembly temperatures after emplacement, limits the introduction of moderator into the disposal container during the criticality control period, resists corrosion in the expected handling and repository environments, and provides containment of waste in the event of an accident

  8. The geochemical environment of nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Gascoyne, M.

    1995-01-01

    The concept for disposal of Canada's nuclear fuel waste in a geologic environment on the Canadian Shield has recently been presented by Atomic Energy of Canada Limited (AECL) to governments, scientists, and the public, for review. An important part of this concept concerns the geochemical environment of a disposal vault and includes consideration of rock and groundwater compositions, geochemical interactions between rocks, groundwaters, and emplaced vault materials, and the influences and significance of anthropogenic and microbiological effects following closure of the vault. This paper summarizes the disposal concept and examines aspects of the geochemical environment. The presence of saline groundwaters and reducing conditions at proposed vault depths (500-1000 m) in the Canadian Shield has an important bearing on the stability of the used nuclear fuel, its container, and buffer and backfill materials. The potential for introduction of anthropogenic contaminants and microbes during site investigations and vault excavation, operation, and sealing is described with examples from AECL's research areas on the Shield and in their underground research laboratory in southeastern Manitoba. (author)

  9. Cost estimate of Olkiluoto disposal facility for spent nuclear fuel

    International Nuclear Information System (INIS)

    Kukkola, T.; Saanio, T.

    2005-03-01

    The cost estimate covers the underground rock characterisation facility ONKALO, the investment and the operating costs of the above and underground facilities, the decommissioning of the encapsulation plant and the closure costs of the repository. The above ground facility is a once-investment; a re-investment takes place after 37 years operation. The repository is extended stepwise thus also the investment take place in stages. Annual operating costs are calculated with different operating efficiencies. The total investment costs of the disposal facility are estimated to be 503 M euro (Million Euros), the total operating costs are 1,923 M euro and the decommissioning and the closure costs are 116 M euro totaling 2,542 M euro. The investment costs of the above ground facility are 142 M euro, the operating costs are 1,678 M euro. The repository investment costs are 360 M euro and the operating costs are 245 M euro. The decommissioning costs are 7 M euro and the closure costs are 109 M euro. The costs are calculated by using the price level of December 2003. The cost estimate is based on a plan, where the spent fuel is encapsulated and the disposal canisters are disposed into the bedrock at a depth of about 420 meters in one storey. In the encapsulation process, the fuel assemblies are closed into composite canisters, in which the inner part of the canister is made of nodular cast iron and the outer wall of copper having a thickness of 50 mm. The inner canister is closed gas-tight by a bolted steel lid, and the electron beam welding method is used to close the outer copper lid. The encapsulation plant is independent and located above the deep repository spaces. The disposal canisters are transported to the repository by the lift. The disposal tunnels are constructed and closed in stages according the disposal canisters disposal. The operating time of the Loviisa nuclear power plant units is assumed to be 50 years and the operating time of the Olkiluoto nuclear power

  10. Iron oxide redox chemistry and nuclear fuel disposal

    International Nuclear Information System (INIS)

    Jobe, D.J.; Lemire, R.J.; Taylor, P.

    1997-04-01

    Solubility and stability data for iron (III) oxides and aqueous Fe(II) and Fe(III) species are reviewed, and selected values are used to calculate potential-pH diagrams for the iron system at temperatures of 25 and 100 deg C, chloride activities {C1 - } = 10 -2 and 1 mol/kg, total carbonate activity {C T } = 10 -3 mol/kg, and iron(III) oxide/oxyhydroxide solubility products (25 deg C values) K sp = {Fe 3+ }{OH - } 3 = 10 -38.5 , 10 -40 and 10 -42 . The temperatures and anion concentrations bracket the range of conditions expected in a Canadian nuclear fuel waste disposal vault. The three solubility products represent a conservative upper limit, a most probable value, and a minimum credible value, respectively, for the iron oxides likely to be important in controlling redox conditions in a disposal vault for CANDU nuclear reactor fuel. Only in the first of these three cases do the calculated redox potentials significantly exceed values under which oxidative dissolution of the fuel may occur. (author)

  11. Program SYVAC, for stochastic assessment of nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Sherman, G.R.; Hoffman, K.J.; Donahue, D.C.

    1985-01-01

    In this paper, the computer program SYVAC, used to assess concepts for the disposal of nuclear fuel waste, is described with regard to the development approach, the basic program structure, and quality assurance. The interrelationships of these aspects are illustrated by detailed descriptions of two concepts of fundamental importance to the program: the method of selecting parameter values from input probability density functions, and the numerical evaluation of the convolution integral. Quality assurance procedures, including different types of comparisons and peer review, are presented

  12. The disposal of Canada's nuclear fuel waste: engineered barriers alternatives

    International Nuclear Information System (INIS)

    Johnson, L.H.; Tait, J.C.; Shoesmith, D.W.; Crosthwaite, J.L.; Gray, M.N.

    1994-01-01

    The concept for disposal of Canada's nuclear fuel waste involves emplacing the waste in a vault excavated at a depth of 500 to 1000 m in plutonic rock of the Canadian Shield. The solid waste would be isolated from the biosphere by a multibarrier system consisting of engineered barriers, including long-lived containers and clay and cement-based sealing materials, and the natural barrier provided by the massive geological formation. The technical feasibility of this concept and its impact on the environment and human health are being documented in an Environmental Impact Statement (EIS), which will be submitted for review under the federal Environmental Assessment and Review Process. This report, one of nine EIS primary references, describes the various alternative designs and materials for engineered barriers that have been considered during the development of the Canadian disposal concept and summarizes engineered barrier concepts being evaluated in other countries. The basis for the selection of a reference engineered barrier system for the EIS is presented. This reference system involves placing used CANDU (Canada Deuterium Uranium) fuel bundles in titanium containers, which would then be emplaced in boreholes drilled in the floor of disposal rooms. Clay-based sealing materials would be used to fill both the space between the containers and the rock and the remaining excavations. In the section on waste forms, the properties of both used-fuel bundles and solidified high-level wastes, which would be produced by treating wastes resulting from the reprocessing of used fuel, are discussed. Methods of solidifying the wastes and the chemical durability of the solidified waste under disposal conditions are reviewed. Various alternative container designs are reviewed, ranging from preliminary conceptual designs to designs that have received extensive prototype testing. Results of structural performance, welding and inspection studies are also summarized. The corrosion of

  13. A proposed risk acceptance criterion for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Mehta, K.

    1985-06-01

    The need to establish a radiological protection criterion that applies specifically to disposal of high level nuclear fuel wastes arises from the difficulty of applying the present ICRP recommendations. These recommendations apply to situations in which radiological detriment can be actively controlled, while a permanent waste disposal facility is meant to operate without the need for corrective actions. Also, the risks associated with waste disposal depend on events and processes that have various probabilities of occurrence. In these circumstances, it is not suitable to apply standards that are based on a single dose limit as in the present ICRP recommendations, because it will generally be possible to envisage events, perhaps rare, that would lead to doses above any selected limit. To overcome these difficulties, it is proposed to base a criterion for acceptability on a set of dose values and corresponding limiting values of probabilities; this set of values constitutes a risk-limit line. A risk-limit line suitable for waste disposal is proposed that has characteristics consistent with the basic philosophy of the ICRP and UNSCEAR recommendations, and is based on levels on natural background radiation

  14. Conditioning of spent nuclear fuel for permanent disposal

    International Nuclear Information System (INIS)

    Laidler, J.J.

    1994-01-01

    A compact, efficient method for conditioning spent nuclear fuel is under development This method, known as pyrochemical processing, or open-quotes pyroprocessing,close quotes provides a separation of fission products from the actinide elements present in spent fuel and further separates pure uranium from the transuranic elements. The process can facilitate the timely and environmentally-sound treatment of the highly diverse collection of spent fuel currently in the inventory of the United States Department of Energy (DOE). The pyroprocess utilizes elevated-temperature processes to prepare spent fuel for fission product separation; that separation is accomplished by a molten salt electrorefining step that provides efficient (99.9%) separation of transuranics. The resultant waste forms from the pyroprocess are stable under envisioned repository environment conditions and highly leach-resistant. Treatment of any spent fuel type produces a set of common high-level waste forms, one a mineral and the other a metal alloy, that can be readily qualified for repository disposal and preclude the substantial costs that would be associated with the qualification of the numerous spent fuel types included in the DOE inventory

  15. Conditioning of spent nuclear fuel for permanent disposal

    International Nuclear Information System (INIS)

    Laidler, J.J.

    1994-01-01

    A compact, efficient method for conditioning spent nuclear fuel is under development. This method, known as pyrochemical processing, or pyroprocessing, provides a separation of fission products from the actinide elements present in spent fuel and further separates pure uranium from the transuranic elements. The process can facilitate the timely and environmentally-sound treatment of the highly diverse collection of spent fuel currently in the inventory of the US Department of Energy (DOE). The pyroprocess utilizes elevated-temperature processes to prepare spent fuel for fission product separation; that separation is accomplished by a molten salt electrorefining step that provides efficient (> 99.9%) separation of transuranics. The resultant waste forms from the pyroprocess are stable under envisioned repository environment conditions and highly leach-resistant. Treatment of any spent fuel type produces a set of common high-level waste forms, one a mineral and the other a metal alloy, that can be readily qualified for repository disposal and that avoid the substantial costs that would be associated with the qualification of the numerous spent fuel types included in the DOE inventory

  16. Final disposal of spent nuclear fuel - basis for site selection

    International Nuclear Information System (INIS)

    Anttila, P.

    1995-05-01

    International organizations, e.g. IAEA, have published several recommendations and guides for the safe disposal of radioactive waste. There are three major groups of issues affecting the site selection process, i.e. geological, environmental and socioeconomic. The first step of the site selection process is an inventory of potential host rock formations. After that, potential study areas are screened to identify sites for detailed investigations, prior to geological conditions and overall suitability for the safe disposal. This kind of stepwise site selection procedure has been used in Finland and in Sweden. A similar approach has been proposed in Canada, too. In accordance with the amendment to the Nuclear Energy Act, that entered into force in the beginning of 1995, Imatran Voima Oy has to make preparations for the final disposal of spent fuel in the Finnish bedrock. Relating to the possible site selection, the following geological factors, as internationally recommended and used in the Nordic countries, should be taken into account: topography, stability of bedrock, brokenness and fracturing of bedrock, size of bedrock block, rock type, predictability and natural resources. The bedrock of the Loviisa NPP site is a part of the Vyborg rapakivi massif. As a whole the rapakivi granite area forms a potential target area, although other rock types or areas cannot be excluded from possible site selection studies. (25 refs., 7 figs.)

  17. Estimating the cost of disposal for Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    Ates, Y.

    1996-07-01

    Atomic Energy of Canada Ltd (AECL) prepared an Environmental Impact Statement and nine supporting Primary Reference Documents on the concept for disposal of Canada's nuclear fuel waste. This report summarizes the basis of the cost estimate which is provided in the primary reference document on engineering for a disposal facility. The scope of the cost estimate is explained by describing the key features of the disposal facility design, by noting the major assumptions made in preparing the estimates, and by listing the included and excluded cost components. An activity-based project planning and control method is explained whereby the project schedule, costs, and personnel requirements are interlinked; forming an integrated perspective on the total project life cycle. The summary and distribution of costs in each project stage by major facility or activity are presented. The results of studies which reviewed the overall cost estimate are also described. These studies indicate that, within the scope, the estimate is reasonable and compares well with similar international studies. (author)

  18. Reduction of uranium in disposal conditions of spent nuclear fuel

    International Nuclear Information System (INIS)

    Myllykylae, E.

    2008-02-01

    This literature study is a summary of publications, in which the reduction of uranium by iron has been investigated in anaerobic groundwater conditions or in aqueous solution in general. The basics of the reduction phenomena and the oxidation states, complexes and solubilities of uranium and iron in groundwaters are discussed as an introduction to the subject, as well as, the Finnish disposal concept of spent nuclear fuel. The spent fuel itself mainly (∼96 %) consists of a sparingly soluble uranium(IV) dioxide, UO 2 (s), which is stable phase in the anticipated reducing disposal conditions. If spent fuel gets in contact with groundwater, oxidizing conditions might be induced by the radiolysis of water, or by the intrusion of oxidizing glacial melting water. Under these conditions, the oxidation and dissolution of uranium dioxide to more soluble U(VI) species could occur. This could lead to the mobilization of uranium and other components of spent fuel matrix including fission products and transuranium elements. The reduction of uranium back to oxidation state U(IV) can be considered as a favourable immobilization mechanism in a long-term, leading to precipitation due to the low solubility of U(IV) species. The cast iron insert of the disposal canister and its anaerobic corrosion products are the most important reductants under disposal conditions, but dissolved ferrous iron may also function as reductant. Other iron sources in the buffer or near-field rock, are also considered as possible reductants. The reduction of uranium is a very challenging phenomenon to investigate. The experimental studies need e.g. well-controlled anoxic conditions and measurements of oxidation states. Reduction and other simultaneous phenomena are difficult to distinghuish. The groundwater conditions (pH, Eh and ions) influence on the prevailing complexes of U and Fe and on forming corrosion products of iron and, thus they determine also the redox chemistry. The partial reduction of

  19. Final disposal of spent nuclear fuel in the Finnish bedrock

    International Nuclear Information System (INIS)

    1992-12-01

    Teollisuuden Voima Oy (TVO) studies Finnish bedrock for the final disposal of the spent nuclear fuel from the Olkiluoto nuclear power plant. The study is in accordance with the decision in principle by Finnish government in 1983. The report is the summary of the preliminary site investigations carried out during the years 1987-1992. On the basis of these investigations a few areas will be selected for detailed site investigation. The characterization comprises five areas selected from the shortlist of potential candidate areas resulted in the earlier study during 1983-1985. Areas are located in different parts of Finland and they represent the main formations of the Finnish bedrock. Romuvaara area in Kuhmo and Veitsivaara area in Hyrynsalmi represent the Archean basement. Kivetty area in Konginkangas consists of mainly younger granitic rocks. Syyry in Sievi is located in transition area of Svecofennidic rocks and granitic rocks. Olkiluoto in Eurajoki represents migmatites in southern Finland. For the field investigations area-specific programs were planned and executed. The field investigations have comprised airborne survey by helicopter, geophysical surveys, geological mappings and samplings, deep and shallow core drillings, geophysical and hydrological borehole measurements and groundwater samplings

  20. The disposal of Canada's nuclear fuel waste: public involvement and social aspects

    International Nuclear Information System (INIS)

    Greber, M.A.; Frech, E.R.; Hillier, J.A.R.

    1994-01-01

    This report describes the activities undertaken to provide information to the public about the Canadian Nuclear Fuel Waste Management Program as well as the opportunities for public involvement in the direction and development of the disposal concept through government inquiries and commissions and specific initiatives undertaken by AECL. Public viewpoints and the major issues identified by the public to be of particular concern and importance in evaluating the acceptability of the concept are described. In addition, how the issues have been addressed during the development of the disposal concept or how they could be addressed during implementation of the disposal concept are presented. There is also discussion of public perspectives of risk, the ethical aspects of nuclear fuel waste disposal, and public involvement in siting a nuclear fuel waste disposal facility. The Canadian Nuclear Fuel Waste Management Program is funded jointly by AECL and Ontario Hydro under the auspices of the CANDU Owners Group. (author)

  1. Storage, transportation and disposal system for used nuclear fuel assemblies

    Science.gov (United States)

    Scaglione, John M.; Wagner, John C.

    2017-01-10

    An integrated storage, transportation and disposal system for used fuel assemblies is provided. The system includes a plurality of sealed canisters and a cask sized to receive the sealed canisters in side by side relationship. The plurality of sealed canisters include an internal basket structure to receive a plurality of used fuel assemblies. The internal basket structure includes a plurality of radiation-absorbing panels and a plurality of hemispherical ribs generally perpendicular to the canister sidewall. The sealed canisters are received within the cask for storage and transportation and are removed from the cask for disposal at a designated repository. The system of the present invention allows the handling of sealed canisters separately or collectively, while allowing storage and transportation of high burnup fuel and damaged fuel to the designated repository.

  2. Safety analysis of disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Vieno, T.

    1994-04-01

    The spent fuel from the Olkiluoto NPP (TVO I and II) is planned to be disposed of in a repository to be constructed at a depth of about 500 meters in the crystalline bedrock. The thesis is dealing with the safety analysis of the disposal. The main topics presented in the thesis are: (1) The amount of radioactive properties of the spent fuel, (2) The canister design and the planned disposal concept, (3) The results of the preliminary site investigations, (4) Discussion of the multi-barrier principle, (5) The general principles and methodology of the TVO-92 safety analysis, (6) Groundwater flow analysis, (7) Durability and behaviour of the canister, (8) Biosphere analysis and reference scenario, and (9) The sensitivity and uncertainty analyses. (246 refs., 75 figs., 44 tabs.)

  3. Corrosion of copper under Canadian nuclear fuel waste disposal conditions

    International Nuclear Information System (INIS)

    King, F.; Litke, C.D.

    1990-01-01

    The corrosion of copper was studied under Canadian nuclear fuel waste disposal conditions. The groundwater in a Canadian waste vault is expected to be saline, with chloride concentrations from 0.1 to 1.0 mol/l. The container would be packed in a sand/clay buffer, and the maximum temperature on the copper surface would be 100C; tests were performed up to 150C. Radiation fields will initially be around 500 rad/h, and conditions will be oxidizing. Sulfides may be present. The minimum design lifetime for the container is 500 years. Most work has been done on uniform corrosion, although pitting has been considered. It was found that the rate of uniform corrosion in aerated NaCl at room temperature is limited by the rate of the anodic reaction, which is controlled mainly by the rate of transport of dissolved metal species away from the copper surface. The rate of corrosion should become controlled by the transport of oxygen to the copper surface only at very low oxygen concentrations. In the presence of gamma radiation the corrosion rate may never become cathodically transport limited. In compacted buffer material, the corrosion rate appears to be limited by the rate of transport of copper species away from the corroding surface. The authors recommend that long-term predictions of container lifetime should be based on the known rate-determining step for the overall corrosion process. 8 refs

  4. Effects of spent nuclear fuel aging on disposal requirements

    International Nuclear Information System (INIS)

    McKee, R.W.; Johnson, K.I.; Huber, H.D.; Bierschbach, M.C.

    1991-10-01

    This paper describes results of a study to analyze the waste management systems effects of extended spent fuel aging on spent fuel disposal requirements. The analysis considers additional spent fuel aging up to a maximum of 50 years relative to the currently planned 2010 repository startup in the United States. As part of the analysis, an equal energy disposition (EED) methodology was developed for determining allowable waste emplacement densities and waste container loading in a geologic repository. Results of this analysis indicate that substantial benefits of spent fuel aging will already have been achieved by a repository startup in 2010 (spent fuel average age will be 28 years). Even so, further significant aging benefits, in terms of reduced emplacement areas and mining requirements and reduced number of waste containers, will continue to accrue for at least another 50 years when the average spent fuel age would be 78 years, if the repository startup is further delayed

  5. Vault submodel for the second interim assessment of the Canadian concept for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    LeNeveu, D.M.

    1986-02-01

    The consequences to man and the environment of the disposal of nuclear fuel waste are being studied within the Canadian Nuclear Fuel Waste Management Program. The concept being assessed is that of a sealed disposal vault at a depth of 1000 m in plutonic rock in the Canadian Shield. To determine the consequences, the vault and its environment are simulated using a SYstem Variability Analysis Code (SYVAC), a stochastic model of the disposal system. SYVAC contains three submodels that represent the three major parts of the disposal system: the vault, the geosphere and the biosphere. This report documents the conceptual and mathematical framework of the vault submodel

  6. The analysis of geological formations from Romania available for disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Barariu, Gheorghe; Alecu, Catalin

    2003-01-01

    The majority of countries possessing nuclear power industry has not yet decided upon the option about closing the nuclear cycle. There are still in progress projects concerning the final disposal, while worldwide it is not foreseen the reprocessing of the whole amount of reusable fissionable materials. The annual worldwide production of used nuclear fuel continues to be about 10 500 - 11 000 tones of heavy metal. The difficulties in designing used fuel final disposal repositories led to the design of some interim storage facilities, providing a satisfactory safety level for biosphere. On the other hand, regardless of the selected option we respect to closing the nuclear cycle, a final repository must exists, either for the high level wastes resulted from reprocessing the used nuclear fuel or for the used fuel considered radioactive waste. Although, presently, in Romania, the nuclear fuel extracted from the reactor after its 'useful life' is declared as radioactive waste, it may contain a certain amount of fissionable material that could be used in other types of reactors. This possibility implies taking into account the concept regarding the recovery of fuel after a certain period of time, although, by definition, final disposal means prevention of this possibility. The harmonization of the Romanian legislation with that of the European Community and the adhering to the European Conventions, poses among other issues the problem of the final disposal of the used nuclear fuel. Starting from these major requirements the paper presents the main aspects of the Project 011/11.10.2001, entitled 'Researches for the selection and preliminary characterization of the host rock for the final disposal of the used nuclear fuel', part of The National Research Program: Medium, Energy and Resources. A complex analysis regarding the implications on the design of the Used Nuclear Fuel Final Disposal Repository in Romania was performed, the analysis of the available geological

  7. Environmental Impact Statement on the concept for disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    1994-01-01

    This report describes the many fundamental issues relating to the strategy being proposed by Atomic Energy of Canada Limited for the long-term management of nuclear fuel waste. It discusses the need for a method for disposal of nuclear fuel waste that would permanently protect human health and the natural environment and that would not unfairly burden future generations. It also describes the background and mandate of the Nuclear Fuel Waste Management Program in Canada.

  8. Environmental Impact Statement on the concept for disposal of Canada's nuclear fuel waste

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-07-01

    This report describes the many fundamental issues relating to the strategy being proposed by Atomic Energy of Canada Limited for the long-term management of nuclear fuel waste. It discusses the need for a method for disposal of nuclear fuel waste that would permanently protect human health and the natural environment and that would not unfairly burden future generations. It also describes the background and mandate of the Nuclear Fuel Waste Management Program in Canada.

  9. Environmental Impact Statement on the concept for disposal of Canada's nuclear fuel waste

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-07-01

    This report describes the many fundamental issues relating to the strategy being proposed by Atomic Energy of Canada Limited for the long-term management of nuclear fuel waste. It discusses the need for a method for disposal of nuclear fuel waste that would permanently protect human health and the natural environment and that would not unfairly burden future generations. It also describes the background and mandate of the Nuclear Fuel Waste Management Program in Canada.

  10. Backfill formulations for a nuclear fuel waste disposal vault

    International Nuclear Information System (INIS)

    Yong, R.N.; Boonsinsuk, P.; Wong, G.; Ming, X.D.; Caporuscio, F.; Lytle, P.

    1987-01-01

    Atomic Energy of Canada Limited and Ontario Hydro are studying the concept of disposing of nuclear fuel wastes in a vault within the Canadian Shield. After nuclear waste containers have been emplaced in a vault, the vault will have to be backfilled permanently. A suitable backfill material should have low hydraulic conductivity and high radionuclide sorption capacity. The research was done with a goal of recommending a specification for formulating this backfill material. This report suggests that such a backfill material should be a mixture of coarse aggregates and swelling clay. Actual trial mixtures were prepared using crushed granite and natural Lake Agassiz clay. Various trial mixtures were subjected to constant-head permeability tests. The results indicate that the hydraulic conductivity of the aggregate-clay mixtures could be close to those of the clay (by itself) when the clay content was in the range of 25% or more. The resulting hydraulic conductivity of about 10 -10 m/s is considered to be low, especially since the maximum grain size is 19.1 mm. Selected mixtures were evaluated for free swell and swelling pressure, both of which increased with increasing clay content. When the clay content was 25%, the free swell was about 4%, compared with 6% for the 100% clay. The corresponding swelling pressure was about 16 kPa - in comparison to 48 kPa for the 100% clay. These results indicate that the proposed backfill material should contain about 25% clay, with a maximum grain size of 19.1 mm. The selected mixture was also tested to evaluate the effects of mixing methods, load-carrying capacity and compaction techniques suitable for the underground vault conditions. The proposed backfill material appeared to perform satisfactorily according to the criteria demanded. The backfill material proposed was further tested for its behaviour during water intake. The unsaturated hydraulic conductivity was found to be approximately 10 -10 m/s and the swelling pressure was

  11. Summary of the Environmental Impact Statement on the concept for disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    1994-01-01

    This is the Summary of the Environmental Impact Statement (EIS) prepared by Atomic Energy of Canada Limited (AECL) on the concept for disposal of Canada's nuclear fuel waste. The proposed concept is a method for geological disposal, based on a system of natural and engineered barriers. The EIS provides information requested by the Environmental Assessment Panel reviewing the disposal concept and presents AECL's case for the acceptability of the concept. The introductory chapter of this Summary provides background information on several topics related to nuclear fuel waste, including current storage practices for used fuel, the need for eventual disposal of nuclear fuel waste, the options for disposal, and the reasons for Canada's focus on geological disposal. Chapter 2 describes the concept for disposal of nuclear fuel waste. Because the purpose of implementing the concept would he to protect human health and the natural environment far into the future, we discuss the long-term performance of a disposal system and present a case study of potential effects on human health and the natural environment after the closure of a disposal facility. The effects and social acceptability of disposal would depend greatly on how the concept was implemented. Chapter 3 describes AECL's proposed approach to concept implementation. We discuss how the public would be involved in implementation; activities that would be undertaken to protect human health, the natural environment, and the socio-economic environment; and a case study of the potential effects of disposal before the closure of a disposal facility. The last chapter presents AECL's Conclusion, based on more than 15 years of research and development, that implementation of the disposal concept represents a means by which Canada can safely dispose of its nuclear fuel waste. This chapter also presents AECL's recommendation that Canada progress toward disposal of its nuclear fuel waste by undertaking the first stage of concept

  12. Impact of nuclear data uncertainty on safety calculations for spent nuclear fuel geological disposal

    Directory of Open Access Journals (Sweden)

    Herrero J.J.

    2017-01-01

    Full Text Available In the design of a spent nuclear fuel disposal system, one necessary condition is to show that the configuration remains subcritical at time of emplacement but also during long periods covering up to 1,000,000 years. In the context of criticality safety applying burn-up credit, k-eff eigenvalue calculations are affected by nuclear data uncertainty mainly in the burnup calculations simulating reactor operation and in the criticality calculation for the disposal canister loaded with the spent fuel assemblies. The impact of nuclear data uncertainty should be included in the k-eff value estimation to enforce safety. Estimations of the uncertainty in the discharge compositions from the CASMO5 burn-up calculation phase are employed in the final MCNP6 criticality computations for the intact canister configuration; in between, SERPENT2 is employed to get the spent fuel composition along the decay periods. In this paper, nuclear data uncertainty was propagated by Monte Carlo sampling in the burn-up, decay and criticality calculation phases and representative values for fuel operated in a Swiss PWR plant will be presented as an estimation of its impact.

  13. Developments in the Canadian program for geological disposal of nuclear fuel waste

    International Nuclear Information System (INIS)

    Allan, C.J.; Nuttall, K.

    1996-01-01

    The Canadian Nuclear Fuel Waste Management Program is at the end of disposal concept and technology development and is now undergoing a comprehensive environmental review. This paper will review: the history of the Canadian program; the disposal concept and the associated technologies; the program achievements and the lessons learned; and the status of the environmental review. (author)

  14. Material streams in the fuel supply to and disposal of waste from nuclear power stations

    International Nuclear Information System (INIS)

    Merz, E.

    1990-01-01

    The nuclear fuel cycle is characterized by specifically small, but complex material streams. The fresh fuel derived from natural uranium is fed into the cycle at the stage of fuel element fabrication, while at the end stage, waste from spent fuel element reprocessing, or non-reprocessible fuel elements, are taken out of the cycle and prepared for ultimate disposal. The alternative methods of waste management, reprocessing or direct ultimate disposal, are an issue of controversial debate with regard to their differences in terms of supply policy, economic and ecological aspects. (orig.) [de

  15. Industrial feasibility study of a spent nuclear fuel package for direct deep disposal

    International Nuclear Information System (INIS)

    Le Lous, K.; Loubrieu, J.; Chupeau, J.; Serpantie, J.P.; Becle, D.; Aubry, S.

    2001-01-01

    EDF has undertaken to study the industrial feasibility of a spent nuclear fuel package meeting direct disposal requirements. In this context, a disposal concept has been defined in which packages are cooled in place until the module is finally sealed. Indeed, one of the objectives of that disposal concept is to reduce the underground area occupied by the repository. A functional analysis has been performed within the framework of that ventilated disposal concept, taking into account the phases of the package lifetime from its conditioning until the disposal post-closure phase. An industrial feasibility study is in progress, which takes into account the functional specifications and some preliminary studies. (author)

  16. Second interim assessment of the Canadian concept for nuclear fuel waste disposal. Volume 1

    International Nuclear Information System (INIS)

    Wuschke, D.M.; Gillespie, P.A.; Main, D.E.

    1985-07-01

    The nuclear fuel waste disposal concept chosen for development and assessment in Canada involves the isolation of corrosion-resistant containers of waste in a vault located deep in plutonic rock. As the concept and the assessment tools are developed, periodic assessments are performed to permit evaluation of the methodology and provide feedback to those developing the concept. The ultimate goal of these assessments is to predict what impact the disposal system would have on man and the environment if the concept were implemented. The second assessment was performed in 1984 and is documented in the Second Interim assessment of the Canadian Concept for Nuclear Fuel Waste Disposal Volumes 1 to 4. This volume, entitled Summary, is a condensation of Volumes 2, 3 and 4. It briefly describes the Canadian nuclear fuel waste disposal concept, and the methods and results of the second interim pre-closure and post-closure assessments of that concept. 46 refs

  17. Status of nuclear fuel reprocessing, spent fuel storage, and high-level waste disposal. Nuclear Fuel Cycle Committee, California Energy Resources Conservation and Development Commission. Draft report

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    An analysis of the current status of technologies and issues in the major portions of the back-end of the nuclear fuel cycle is presented. The discussion on nuclear fuel reprocessing covers the reprocessing requirement, reprocessing technology assessment, technology for operation of reprocessing plants, and approval of reprocessing plants. The chapter devoted to spent fuel storage covers the spent fuel storge problem, the legislative response, options for maintaining full core discharge capacity, prospective availability of alterntive storage options, and the outlook for California. The existence of a demonstrated, developed high-level waste disposal technology is reviewed. Recommendations for Federal programs on high-level waste disposal are made

  18. Environmental Impact Statement. March 2011. Interim storage, encapsulation and final disposal of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    2011-07-01

    An Environmental Impact Statement (EIS) shall be prepared and submitted along with applications for permissibility and a licence under the Environmental Code and a licence under the Nuclear Activities Act for new nuclear facilities. This Environmental Impact Statement has been prepared by Svensk Kaernbraenslehantering AB (the Swedish Nuclear Fuel and Waste Management Co, SKB) to be included in the licence applications for continued operation of Clab (central interim storage facility for spent nuclear fuel) in Simpevarp in Oskarshamn Municipality and construction and operation of facilities for encapsulation (integrated with Clab) and final disposal of spent nuclear fuel in Forsmark in Oesthammar Municipality

  19. Environmental Impact Statement. March 2011. Interim storage, encapsulation and final disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    2011-01-01

    An Environmental Impact Statement (EIS) shall be prepared and submitted along with applications for permissibility and a licence under the Environmental Code and a licence under the Nuclear Activities Act for new nuclear facilities. This Environmental Impact Statement has been prepared by Svensk Kaernbraenslehantering AB (the Swedish Nuclear Fuel and Waste Management Co, SKB) to be included in the licence applications for continued operation of Clab (central interim storage facility for spent nuclear fuel) in Simpevarp in Oskarshamn Municipality and construction and operation of facilities for encapsulation (integrated with Clab) and final disposal of spent nuclear fuel in Forsmark in Oesthammar Municipality

  20. An approach to criteria, design limits and monitoring in nuclear fuel waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, G R; Baumgartner, P; Bird, G A; Davison, C C; Johnson, L H; Tamm, J A

    1994-12-01

    The Nuclear Fuel Waste Management Program has been established to develop and demonstrate the technology for safe geological disposal of nuclear fuel waste. One objective of the program is to show that a disposal system (i.e., a disposal centre and associated transportation system) can be designed and that it would be safe. Therefore the disposal system must be shown to comply with safety requirements specified in guidelines, standards, codes and regulations. The components of the disposal system must also be shown to operate within the limits specified in their design. Compliance and performance of the disposal system would be assessed on a site-specific basis by comparing estimates of the anticipated performance of the system and its components with compliance or performance criteria. A monitoring program would be developed to consider the effects of the disposal system on the environment and would include three types of monitoring: baseline monitoring, compliance monitoring, and performance monitoring. This report presents an approach to establishing compliance and performance criteria, limits for use in disposal system component design, and the main elements of a monitoring program for a nuclear fuel waste disposal system. (author). 70 refs., 9 tabs., 13 figs.

  1. An approach to criteria, design limits and monitoring in nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Simmons, G.R.; Baumgartner, P.; Bird, G.A.; Davison, C.C.; Johnson, L.H.; Tamm, J.A.

    1994-12-01

    The Nuclear Fuel Waste Management Program has been established to develop and demonstrate the technology for safe geological disposal of nuclear fuel waste. One objective of the program is to show that a disposal system (i.e., a disposal centre and associated transportation system) can be designed and that it would be safe. Therefore the disposal system must be shown to comply with safety requirements specified in guidelines, standards, codes and regulations. The components of the disposal system must also be shown to operate within the limits specified in their design. Compliance and performance of the disposal system would be assessed on a site-specific basis by comparing estimates of the anticipated performance of the system and its components with compliance or performance criteria. A monitoring program would be developed to consider the effects of the disposal system on the environment and would include three types of monitoring: baseline monitoring, compliance monitoring, and performance monitoring. This report presents an approach to establishing compliance and performance criteria, limits for use in disposal system component design, and the main elements of a monitoring program for a nuclear fuel waste disposal system. (author). 70 refs., 9 tabs., 13 figs

  2. Spent nuclear fuel for disposal in the KBS-3 repository

    International Nuclear Information System (INIS)

    Grahn, Per; Moren, Lena; Wiborgh, Maria

    2010-12-01

    The report is included in a set of Production reports, presenting how the KBS-3 repository is designed, produced and inspected. The set of reports is included in the safety report for the KBS-3 repository and repository facility. The report provides input to the assessment of the long-term safety, SR-Site as well as to the operational safety report, SR-Operation. The report presents the spent fuel to be deposited, and the requirements on the handling and selection of fuel assemblies for encapsulation that follows from that it shall be deposited in the KBS-3 repository. An overview of the handling and a simulation of the encapsulation and the resulting canisters to be deposited are presented. Finally, the initial state of the encapsulated spent nuclear fuel is given. The initial state comprises the radionuclide inventory and other data required for the assessment of the long-term safety

  3. Spent nuclear fuel for disposal in the KBS-3 repository

    Energy Technology Data Exchange (ETDEWEB)

    Grahn, Per; Moren, Lena; Wiborgh, Maria

    2010-12-15

    The report is included in a set of Production reports, presenting how the KBS-3 repository is designed, produced and inspected. The set of reports is included in the safety report for the KBS-3 repository and repository facility. The report provides input to the assessment of the long-term safety, SR-Site as well as to the operational safety report, SR-Operation. The report presents the spent fuel to be deposited, and the requirements on the handling and selection of fuel assemblies for encapsulation that follows from that it shall be deposited in the KBS-3 repository. An overview of the handling and a simulation of the encapsulation and the resulting canisters to be deposited are presented. Finally, the initial state of the encapsulated spent nuclear fuel is given. The initial state comprises the radionuclide inventory and other data required for the assessment of the long-term safety

  4. The nuclear fuel cycle, From the uranium mine to waste disposal

    International Nuclear Information System (INIS)

    2002-09-01

    Fuel is a material that can be burnt to provide heat. The most familiar fuels are wood, coal, natural gas and oil. By analogy, the uranium used in nuclear power plants is called 'nuclear fuel', because it gives off heat too, although, in this case, the heat is obtained through fission and not combustion. After being used in the reactor, spent nuclear fuel can be reprocessed to extract recyclable energy material, which is why we speak of the nuclear fuel cycle. This cycle includes all the following industrial operations: - uranium mining, - fuel fabrication, - use in the reactor, - reprocessing the fuel unloaded from the reactor, - waste treatment and disposal. 'The nuclear fuel cycle includes an array of industrial operations, from uranium mining to the disposal of radioactive waste'. Per unit or mass (e.g. per kilo), nuclear fuel supplies far more energy than a fossil fuel (coal or oil). When used in a pressurised water reactor, a kilo of uranium generates 10,000 times more energy than a kilo of coal or oil in a conventional power station. Also, the fuel will remain in the reactor for a long time (several years), unlike conventional fuels, which are burnt up quickly. Nuclear fuel also differs from others in that uranium has to undergo many processes between the time it is mined and the time it goes into the reactor. For the sake of simplicity, the following pages will only look at nuclear fuel used in pressurised water reactors (or PWRs), because nuclear power plants consisting of one or more PWRs are the most widely used around the world. (authors)

  5. Feasibility of safe terminal disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Nilsson, B.; Papp, T.

    1980-01-01

    The results of the KBS study indicate that safe terminal storage of spent nuclear fuel in crystalline rock is feasible with the technology available today and at a safety level that is well within the limitations recommended by the ICRP. This statement is not only based on the fact that the doses calculated in the KBS study were acceptably low, but even more on the freedom to choose the dimensions of the engineered barriers as well as depth of the repository and to some degree the quality of the host rock

  6. Sea transport of used nuclear fuel and radiactive disposals to a Swedish central store

    International Nuclear Information System (INIS)

    1977-10-01

    Sea transport of used nuclear fuel and radioactive disposals to a Swedish central store. A vessel for transporting used nuclear fuel and radioactive disposals from the power stations at Ringhals, Barsebaeck, Simpevarp and Forsmark to a central store has been projected. Safety aspects, technical and economical aspects have been taken into consideration with regard to the actual volume of goods to be transported. Three different types of vessels are presented and a specification is given for the main alternative. A safety study of the main alternative is shown, regarding collision safety, fire risks and fire extinguishing equipment. (author)

  7. Instant-release fractions for the assessment of used nuclear fuel disposal

    International Nuclear Information System (INIS)

    Garisto, N.C.; Vance, E.R.; Stroes-Gascoyne, S.; Johnson, L.H.

    1989-02-01

    Quantitative estimates of instant-release fractions for the potential release of radionuclides from used CANDU fuel in an underground disposal vault have been made in terms of probability- density functions, taking variability and uncertainty into account. The radionuclides included in this study are 129 I, 135 Cs, 79 Se, 126 Sn, 99 Tc, 14 C, and 3 H. The probability-density functions are based on experimental data on the short term release of radionuclides upon contact with groundwater, and on a knowledge of the solid-state chemistry of used fuel. They provide source terms for the environmental and safety assessment of used nuclear fuel disposal

  8. Advanced techniques for storage and disposal of spent fuel from commercial nuclear power plants

    International Nuclear Information System (INIS)

    Weh, R.; Sowa, W.

    1999-01-01

    Electricity generation using fossil fuel at comparatively low costs forces nuclear energy to explore all economic potentials. The cost advantage of direct disposal of spent nuclear fuel compared to reprocessing gives reason enough to follow that path more and more. The present paper describes components and facilities for long-term storage as well as packaging strategies, developed and implemented under the responsibility of the German utilities operating nuclear power plants. A proposal is made to complement or even to replace the POLLUX cask concept by a system using BSK 3 fuel rod containers together with LB 21 storage casks. (author)

  9. Disposability Assessment: Aluminum-Based Spent Nuclear Fuel Forms

    Energy Technology Data Exchange (ETDEWEB)

    Vinson, D.W.

    1998-11-06

    This report provides a technical assessment of the Melt-Dilute and Direct Al-SNF forms in disposable canisters with respect to meeting the requirements for disposal in the Mined Geologic Disposal System (MGDS) and for interim dry storage in the Treatment and Storage Facility (TSF) at SRS.

  10. Human health considerations in the assessment of Canadian concept for the disposal of nuclear fuel wastes

    International Nuclear Information System (INIS)

    Baweja, A.S.; Tracy, B.L.; Ahier, B.; Bartlett, S.

    1996-01-01

    In 1978, AECL was mandated by the government of Ontario and the federal government to find a permanent disposal solution for spent nuclear fuels. Canada opted for disposal in plutonic rocks of the Canadian shield. The Canadian concept calls for disposal in crystalline rocks at a depth of 500 to 1000 m below the surface. The spent fuel would be contained in a canister, the canister would be emplaced in a vault containing clay-based buffer materials, and the cavity would be backfilled and sealed with natural materials. A Federal Environmental Assessment Review Panel was formed in 1992 to assess the concept for disposal of the spent fuel. In this paper a brief discussion of the human health impacts of the proposed concept is presented. Our assessment is based on the information provided by AECL, namely, the main EIS document, a summary and nine other supporting documents

  11. Direct disposal of spent nuclear fuel. The current status of technology January 1987

    International Nuclear Information System (INIS)

    Wheelton, I.S.; Kelly, B.R.; Wood, E.

    1987-02-01

    The Study assesses the degree and status of research and development worldwide on Direct Disposal of Spent Nuclear Fuel. It is limited to technological, radiological and waste management aspects appertaining to Light Water and AGR Reactor Systems and reviews the 'State of the Art' in terms of applicability to the United Kingdom. The report concludes that much technology exists both at National and International level which the UK can apply to the subject of Direct Disposal. (author)

  12. The disposal of Canada's nuclear fuel waste: comments on the postclosure assessment of a reference system

    International Nuclear Information System (INIS)

    Allan, C.J.; Goodwin, B.W.

    1996-07-01

    Canada, like other countries, is developing technology for disposal of its nuclear fuel waste , based on the concept of geological disposal in stable plutonic rock of the Canadian Shield. The choice of methods, materials, and designs for a disposal system will ultimately be made on the basis of safety, taking into account the characteristics of the specific site on which the facility is to be developed, costs and practicality. As part of its work in developing the technology for the disposal of Canada's nuclear fuel waste, AECL analyzed the performance of a hypothetical disposal facility that incorporates specific design choices for the engineered barriers and that assumes a specific geological setting. This system, comprising the disposal facility and the geological setting, and the results of the performance analysis, is described in an Environmental Impact Statement that AECL submitted in 1994 and in a Primary Reference for the EIS 'The Disposal of Canada's Nuclear Fuel Waste: Postclosure Assessment of a Reference System.' The performance analysis was not intended to be a general proof of the safety of disposal, but rather it presents a safety analysis of one specific system to illustrate the postclosure assessment methodology and to demonstrate that safety could be achieved for the system in question. Although the design of the disposal facility analyzed and the geological setting have specific features, the results obtained from the safety analysis can, however, be used to provide considerable insight into the performance of the various components that comprise the multibarrier geological disposal system. Moreover, the results can show how changes in the performance of specific components can affect the overall performance of the system. This report discusses these aspects of the postclosure analysis. (author)

  13. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Description of the disposal system 2012

    International Nuclear Information System (INIS)

    2012-12-01

    Description of the Disposal System sits within Posiva Oy's Safety Case 'TURVA-2012' report portfolio and has the objective presenting the initial state of the disposal system for the safety case for the disposal of spent nuclear fuel at Olkiluoto, Finland. Disposal system is an entity composed of a repository system and surface environment. The repository system includes the spent nuclear fuel, canister, buffer, backfill, and closure components as well as the host rock. The repository system components have assigned safety functions (except for the spent nuclear fuel) and are subject to requirements. The initial state is presented for each component, and references to the main supporting reports are given to guide the reader for more details. Conditions for each component vary in time and space, due to the time of emplacement and due to the tolerances set for the compositions, geometries and other properties depending on the component. The disposal operation is foreseen to commence ∼ 2020. At the beginning of the postclosure period, around 2120, all the engineered components have been installed and the operation is finalised. The system evolution during the operational phase is discussed in detail in Performance Assessment. The initial state for the host rock is defined to be essentially equal to the baseline conditions prior to starting the construction of the underground characterisation facility ONKALO. For the surface environment, the initial state is the present conditions prevailing. For any other component of the disposal system, the initial state is defined as the state it has when the direct control over that specific part of the system ceases and only limited information can be made available on the subsequent development of conditions in that part of the system or its near field. (orig.)

  14. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Description of the disposal system 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    Description of the Disposal System sits within Posiva Oy's Safety Case 'TURVA-2012' report portfolio and has the objective presenting the initial state of the disposal system for the safety case for the disposal of spent nuclear fuel at Olkiluoto, Finland. Disposal system is an entity composed of a repository system and surface environment. The repository system includes the spent nuclear fuel, canister, buffer, backfill, and closure components as well as the host rock. The repository system components have assigned safety functions (except for the spent nuclear fuel) and are subject to requirements. The initial state is presented for each component, and references to the main supporting reports are given to guide the reader for more details. Conditions for each component vary in time and space, due to the time of emplacement and due to the tolerances set for the compositions, geometries and other properties depending on the component. The disposal operation is foreseen to commence {approx} 2020. At the beginning of the postclosure period, around 2120, all the engineered components have been installed and the operation is finalised. The system evolution during the operational phase is discussed in detail in Performance Assessment. The initial state for the host rock is defined to be essentially equal to the baseline conditions prior to starting the construction of the underground characterisation facility ONKALO. For the surface environment, the initial state is the present conditions prevailing. For any other component of the disposal system, the initial state is defined as the state it has when the direct control over that specific part of the system ceases and only limited information can be made available on the subsequent development of conditions in that part of the system or its near field. (orig.)

  15. Second interim assessment of the Canadian concept for nuclear fuel waste disposal. Volume 2

    International Nuclear Information System (INIS)

    Gillespie, P.A.; Wuschke, D.M.; Guvanasen, V.M.; Mehta, K.K.; McConnell, D.B.; Tamm, J.A.; Lyon, R.B.

    1985-12-01

    The nuclear fuel waste disposal concept chosen for development and assessment in Canada involves the burial of corrosion-resistant containers of waste in a vault located deep in plutonic rock in the Canadian Shield. As the concept and the assessment tools are developed, periodic assessments are performed to permit evaluatin of the methodology and provide feedback to those developing the concept. The ultimate goal of these assessments is to predict what impact the disposal system would have if the concept were implemented. The second assessment was performed in 1984 and is documented in Second Interim Assessment of the Canadian Concept for Nuclear Fuel Waste Disposal - Volumes 1 to 4. This volume, entitled Background, discusses Canadian nuclear fuel wastes and the desirable features of a waste disposal method. It outlines several disposal options being considered by a number of countries, including the option chosen for development and assessment in Canada. The reference disposal systems assumed for the second assessment are described, and the approach used for concept assessment is discussed briefly. 79 refs

  16. Disposal facility for spent nuclear fuel. Environmental impact assessment program

    International Nuclear Information System (INIS)

    1998-01-01

    The report presents the Environmental Impact Assessment (EIA) of the high level radioactive waste disposal in Finland. In EIA different alternatives concerning site selection, construction, operation and sealing of the disposal facility as well as waste transportation and encapsulation of the waste are considered

  17. Management and disposal of used nuclear fuel and reprocessing wastes

    International Nuclear Information System (INIS)

    1983-01-01

    The subject is dealt with in chapters, entitled: introduction (general statement of problem); policy framework (criteria for waste management policy); waste management and disposal, as practised and planned (general; initial storage; reprocessing and conditioning of reprocessing wastes; intermediate storage; transportation; packaging; disposal); international co-operation. Details of the situation in each country concerned (Australia, Belgium, Canada, France, Federal Republic of Germany, Spain, Sweden, Switzerland and United Kingdom) are included as annexes. (U.K.)

  18. Second interim assessment of the Canadian concept for nuclear fuel waste disposal. Volume 3

    International Nuclear Information System (INIS)

    Johansen, K.; Donnelly, K.J.; Gee, J.H.; Green, B.J.; Nathwani, J.S.; Quinn, A.M.; Rogers, B.G.; Stevenson, M.A.; Dunford, W.E.; Tamm, J.A.

    1985-12-01

    The nuclear fuel waste disposal concept chosen for development and assessment in Canada involves the isolation of corrosion-resistant containers of waste in a vault located deep in plutonic rock. As the concept and the assessment tools are developed, periodic assessments are performed to permit evaluation of the methodology and provide feedback to those developing the concept. The ultimate goal of these assessments is to predict what impact the disposal system would have on man and the environment if the concept were implemented. The second such assessment was completed in 1984 and is documented in the Second Interim Assessment of the Canadian Concept for Nuclear Fuel Waste Disposal - Volumes 1-4. This, the third volume of the report, summarizes the pre-closure environmental and safety assessments completed by Ontario Hydro for Atomic Energy of Canada Limited. The preliminary results and their sigificance are discussed. 85 refs

  19. Second interim assessment of the Canadian concept for nuclear fuel waste disposal. Volume 4

    International Nuclear Information System (INIS)

    Wuschke, D.M.; Gillespie, P.A.; Mehta, K.K.; Henrich, W.F.; LeNeveu, D.M.; Guvanasen, V.M.; Sherman, G.R.; Donahue, D.C.; Goodwin, B.W.; Andres, T.H.

    1985-12-01

    The nuclear fuel waste disposal concept chosen for development and assessment in Canada involves the isolation of corrosion-resistant containers of waste in a vault located deep in plutonic rock. As the concept and the assessment tools are developed, periodic assessments are performed to permit evaluation of the methodology and provide feedback to those developing the concept. The ultimate goal of these assessments is to predict what impact the disposal system would have on man and the environment if the concept were implemented. The second such assessment was performed in 1984 and is documented in the Second Interim Assessment of the Canadian Concept for Nuclear Fuel Waste Disposal - Volumes 1-4. This volume, entitled Post-Closure Assessment, describes the methods, models and data used to perform the second post-closure assessment. The results are presented and their significance is discussed. Conclusions and planned improvements are listed. 72 refs

  20. Disposal of high active nuclear fuel waste. A critical review of the Nuclear Fuel Safety (KBS) project on final disposal of vitrified high active nuclear fuel waste

    International Nuclear Information System (INIS)

    1978-01-01

    This report has been prepared by the Swedish Energy Commission's working group for Safety and Environment. The main contributions are by profs. Jan Rydberg of Chalmers University of Technology, Sweden and John W Winchester of Florida State University, USA. The aim of the report is to discuss weather the KBS-project fullfills the Swedish ''Stipulations Act'', that a absolutely safe way of disposing of the nuclear waste must have been demonstrated before any new reactors are allowed to be taken inot use. Rydberg and Winchester do not arrive at similar conclusions. (L.E.)

  1. Back-end of the nuclear fuel cycle. A comparison of the direct disposal and reprocessing options

    International Nuclear Information System (INIS)

    Allan, C.J.; Baumgartner, P.

    1997-01-01

    Based on the need to address public concerns, the need to ensure long-term safety and an ethical concern for future generations, many countries are developing technology to dispose of nuclear fuel waste. The waste substances in used fuel can be disposed of either by directly disposing of the used fuel assemblies themselves, or by disposing of the long-lived waste from fuel reprocessing. The basic thesis of this paper is that the direct disposal of either used fuel or of the long-lived heat-generating and non-heat generating waste that arise from reprocessing is technically and economically feasible and that both options will meet the fundamental objectives of protecting human health and the environment. Decisions about whether, or when, to reprocess used fuel, or about whether to dispose of used fuel directly, are not fundamentally waste management issues. (author)

  2. From laboratory experiments to a geological disposal vault: calculation of used nuclear fuel dissolution rates

    International Nuclear Information System (INIS)

    Sunder, S.; Shoesmith, D.W.; Kolar, M.; Leneveu, D.M.

    1998-01-01

    Calculation of used nuclear fuel dissolution rates in a geological disposal vault requires a knowledge of the redox conditions in the vault. For redox conditions less oxidizing than those causing UO 2 oxidation to the U 3 O 7 , stage, a thermodynamically-based model is appropriate. For more oxidizing redox conditions a kinetic or an electrochemical model is needed to calculate these rates. The redox conditions in a disposal vault will be affected by the radiolysis of groundwater by the ionizing radiation associated with the fuel. Therefore, we have calculated the alpha-, beta- and gamma-dose rates in water in contact with the reference used fuel in the Canadian Nuclear Fuel Waste Management Program (CNFWMP) as a function of cooling time. Also, we have determined dissolution rates of UO 2 fuel as a function of alpha and gamma dose rates from our electrochemical measurements. These room-temperature rates are used to calculate the dissolution rates of used fuel at 100 o C, the highest temperature expected in a container in the CNFWMP, as a function of time since emplacement. It is shown that beta radiolysis of water will be the main cause of oxidation of used CANDU fuel in a failed container. The use of a kinetic or an electrochemical corrosion model, to calculate fuel dissolution rates, is required for a period of ∼1000 a following emplacement of copper containers in the geologic disposal vault envisaged in the CNFWMP. Beyond this time period a thermodynamically-based model adequately predicts the fuel dissolution rates. The results presented in this paper can be adopted to calculate used fuel dissolution rates for other used UO 2 fuels in other waste management programs. (author)

  3. AECL's concept for the disposal of nuclear fuel waste and the importance of its implementation

    International Nuclear Information System (INIS)

    Allan, C.J.

    1993-07-01

    Since 1978, Canada has been investigating a concept for permanently dealing with the nuclear fuel waste from Canadian CANDU (Canada Deuterium Uranium) nuclear generating stations. The concept is based on disposing of the waste in a vault excavated 500 to 1000 m deep in intrusive igneous rock of the Canadian Shield. AECL Research will soon be submitting an environmental impact statement (EIS) on the concept for review by a Panel through the federal environmental assessment and review process (EARP). In accordance with AECL Research's mandate and in keeping with the detailed requirements of the review Panel, AECL Research has conducted extensive studies on a wide variety of technical and socio-economic issues associated with the concept. If the concept is accepted, we can and should continue our responsible approach and take the next steps towards constructing a disposal facility for Canada's used nuclear fuel waste

  4. 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...

  5. Safeguards for final disposal of spent nuclear fuel. Methods and technologies for the Olkiluoto site

    International Nuclear Information System (INIS)

    Okko, O.

    2003-05-01

    The final disposal of the nuclear material shall introduce new safeguards concerns which have not been addressed previously in IAEA safeguards approaches for spent fuel. The encapsulation plant to be built at the site will be the final opportunity for verification of spent fuel assemblies prior to their transfer to the geological repository. Moreover, additional safety and safeguards measures are considered for the underground repository. Integrated safeguards verification systems will also concentrate on environmental monitoring to observe unannounced activities related to possible diversion schemes at the repository site. The final disposal of spent nuclear fuel in geological formation will begin in Finland within 10 years. After the geological site investigations and according to legal decision made in 2001, the final repository of the spent nuclear fuel shall be located at the Olkiluoto site in Eurajoki. The next phase of site investigations contains the construction of an underground facility, called ONKALO, for rock characterisation purposes. The excavation of the ONKALO is scheduled to start in 2004. Later on, the ONKALO may form a part of the final repository. The plans to construct the underground facility for nuclear material signify that the first safeguards measures, e.g. baseline mapping of the site area, need to take prior to the excavation phase. In order to support the development and implementation of the regulatory control of the final disposal programme, STUK established an independent expert group, LOSKA. The group should support the STUK in the development of the technical safeguards requirements, in the implementation of the safeguards and in the evaluation of the plans of the facility operator. This publication includes four background reports produced by this group. The first of these 'NDA verification of spent fuel, monitoring of disposal canisters, interaction of the safeguards and safety issues in the final disposal' describes the new

  6. Encapsulation and handling of spent nuclear fuel for final disposal

    International Nuclear Information System (INIS)

    Loennerberg, B.; Larker, H.; Ageskog, L.

    1983-05-01

    The handling and embedding of those metal parts which arrive to the encapsulation station with the fuel is described. For the encapsulation of fuel two alternatives are presented, both with copper canisters but with filling of lead and copper powder respectively. The sealing method in the first case is electron beam welding, in the second case hot isostatic pressing. This has given the headline of the two chapters describing the methods: Welded copper canister and Pressed copper canister. Chapter 1, Welded copper canister, presents the handling of the fuel when it arrives to the encapsulation station, where it is first placed in a buffer pool. From this pool the fuel is transferred to the encapsulation process and thereby separated from fuel boxes and boron glass rod bundles, which are transported together with the fuel. The encapsulation process comprises charging into a copper canister, filling with molten lead, electron beam welding of the lid and final inspection. The transport to and handling in the final repository are described up to the deposition and sealing in the deposition hole. Handling of fuel residues is treated in one of the sections. In chapter 2, Pressed copper canister, only those parts of the handling, which differ from chapter 1 are described. The hot isostatic pressing process is given in the first sections. The handling includes drying, charging into the canister, filling with copper powder, seal lid application and hot isostatic pressing before the final inspection and deposition. In the third chapter, BWR boxes in concrete moulds, the handling of the metal parts, separated from the fuel, are dealt with. After being lifted from the buffer pool they are inserted in a concrete mould, the mould is filled with concrete, covered with a lid and after hardening transferred to its own repository. The deposition in this repository is described. (author)

  7. Design considerations for sealing the shafts of a nuclear fuel waste disposal vault

    International Nuclear Information System (INIS)

    Mortazavi, M.H.S.; Chan, H.T.; Radhakrishna, H.S.

    1985-05-01

    The shafts in an underground disposal system, which constitute potential pathways between the disposal vault and the biosphere, should be effectively sealed if the system is to perform as a hydrodynamic and geochemical barrier for the safe containment of nuclear fuel waste. In the design of the shaft backfill, consideration should be given to ensure that the backfill and the backfill/rock interface remain intact. Design-related problems, including critical pathways for the transport or radionuclides, configuration of shaft backfill and its functional requirements, the state of stress in a backfilled shaft with particular emphasis on the arching and load transfer phenomenon are discussed in this report

  8. Considerations in managing the assessment of the Canadian nuclear fuel waste disposal concept

    International Nuclear Information System (INIS)

    Dormuth, K.W.; Gillespie, P.A.; Whitaker, S.H.

    1992-01-01

    This paper reports that in developing a concept for disposal of Canada's nuclear fuel waste, AECL has faced challenges because the acceptability of the concept must be established before a site is selected, no agency has been made responsible for implementing the concept if it is selected, and many stakeholders in the review must be satisfied if the concept is to be accepted. The challenges have thus far been met by a program that is well-integrated technically and administratively. However, interactions with stakeholders reviewing the concept present a problem in communication. The authors believe the nature of the nuclear fuel waste disposal issue calls for a cooperative rather than an adversarial approach to problem solving to efficiently deal with the requirements of all the stakeholders

  9. THE ECONOMICS OF REPROCESSING vs. DIRECT DISPOSAL OF SPENT NUCLEAR FUEL

    International Nuclear Information System (INIS)

    Bunn, Matthew; Fetter, Steve; Holdren, John P.; Zwaan, Bob van der

    2003-01-01

    This report assesses the economics of reprocessing versus direct disposal of spent nuclear fuel. The breakeven uranium price at which reprocessing spent nuclear fuel from existing light-water reactors (LWRs) and recycling the resulting plutonium and uranium in LWRs would become economic is assessed, using central estimates of the costs of different elements of the nuclear fuel cycle (and other fuel cycle input parameters), for a wide range of range of potential reprocessing prices. Sensitivity analysis is performed, showing that the conclusions reached are robust across a wide range of input parameters. The contribution of direct disposal or reprocessing and recycling to electricity cost is also assessed. The choice of particular central estimates and ranges for the input parameters of the fuel cycle model is justified through a review of the relevant literature. The impact of different fuel cycle approaches on the volume needed for geologic repositories is briefly discussed, as are the issues surrounding the possibility of performing separations and transmutation on spent nuclear fuel to reduce the need for additional repositories. A similar analysis is then performed of the breakeven uranium price at which deploying fast neutron breeder reactors would become competitive compared with a once-through fuel cycle in LWRs, for a range of possible differences in capital cost between LWRs and fast neutron reactors. Sensitivity analysis is again provided, as are an analysis of the contribution to electricity cost, and a justification of the choices of central estimates and ranges for the input parameters. The equations used in the economic model are derived and explained in an appendix. Another appendix assesses the quantities of uranium likely to be recoverable worldwide in the future at a range of different possible future prices

  10. The disposal of Canada's nuclear fuel waste: postclosure assessment of a reference system

    International Nuclear Information System (INIS)

    Goodwin, B.W.; McConnell, D.B.; Andres, T.H.

    1994-01-01

    The concept for disposal of Canada's nuclear fuel waste is based on a vault located deep in plutonic rock of the Canadian Shield. We document in this report a method to assess the long-term impacts of a disposal facility for nuclear fuel waste. The assessment integrates relevant information from engineering design studies, site investigations, laboratory studies, expert judgment and detailed mathematical analyses to evaluate system performance in terms of safety criteria, guidelines and standards. The method includes the use of quantitative tools such as the Systems Variability Analysis computer Code (SYVAC) to deal with parameter uncertainty and the use of reasoned arguments based on well-established scientific principles. We also document the utility of the method by describing its application to a hypothetical implementation of the concept called the reference disposal system. The reference disposal system generally conforms to the overall characteristics of the concept, except we have made some specific site and design choices so that the assessment would be more realistic. To make the reference system more representative of a real system, we have used the geological observations of the AECL's Whiteshell Research Area located near Lac du Bonnet, Manitoba, to define the characteristics of the geosphere and the groundwater flow system. This research area has been subject to more than a decade of geological and hydrological studies. The analysis of the reference disposal system provides estimates of radiological and chemical toxicity impacts on members of a critical group and estimates of possible impacts on the environment. The latter impacts include estimates of radiation dose to nonhuman organisms. Other quantitative analyses examine the use of derived constraints to improve the margin of safety, the effectiveness of engineered and natural barriers, and the sensitivity of the results to influential features, events, and processes of the reference disposal

  11. Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel and Transuranic Radioactive Wastes (40 CFR Part 191)

    Science.gov (United States)

    This regulation sets environmental standards for public protection from the management and disposal of spent nuclear fuel, high-level wastes and wastes that contain elements with atomic numbers higher than uranium (transuranic wastes).

  12. Radiation and environmental safety of spent nuclear fuel management options based on direct disposal or reprocessing and disposal of high-level radioactive waste

    International Nuclear Information System (INIS)

    Vuori, S.

    1996-05-01

    The report considers the various stages of two nuclear fuel cycle options: direct disposal and reprocessing followed by disposal of vitrified high-level waste. The comparative review is based on the results of previous international studies and concentrates on the radiation and environmental safety aspects of technical solutions based on today's technology. (23 refs., 7 figs., 4 tabs.)

  13. Analysis of scenarios for the direct disposal of spent nuclear fuel disposal conditions as expected in Germany

    International Nuclear Information System (INIS)

    Ashton, P.; Mehling, O.; Mohn, R.; Wingender, H.J.

    1990-01-01

    This report contains an investigation of aspects of the waste management of spent light water reactor fuel by direct disposal in a deep geological formation on land. The areas covered are: interim dry storage of spent fuel with three options of pre-conditioning; conditioning of spent fuel for final disposal in a salt dome repository; disposal of spent fuel (heat-generating waste) in a salt dome repository; disposal of medium and low-level radioactive wastes in the Konrad mine. Dose commitments, effluent discharges and potential incidents were not found to vary significantly for the various conditioning options/salt dome repository types. Due to uncertainty in the cost estimates, in particular the disposal cost estimates, the variation between the three conditioning options examined is not considered as being significant. The specific total costs for the direct disposal strategy are estimated to lie in the range ECU 600 to 700 per kg hm (basis 1988)

  14. The solubility of U, Np, Pu, Th and Tc in a geological disposal vault for used nuclear fuel

    International Nuclear Information System (INIS)

    Lemire, R.J.; Garisto, F.

    1989-12-01

    This document describes the solubility model used to calculate the concentrations of uranium, thorium, technetium, neptunium and plutonium in a geological disposal vault for used nuclear fuel. This model is incorporated in the vault model of SYVAC3-CC3 - the third generation of the Systems Variability Analysis Code used to assess the long-term safety of the disposal of Canada's nuclear fuel waste. The data for the solubility model and the sources for these data are also reported

  15. Choice of method - evaluation of strategies and systems for disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    2010-10-01

    This report deals with the question of how the Swedish spent nuclear fuel is to be disposed of. What are the requirements? What are the alternatives? In the main chapter of the report, an evaluation is made of the KBS-3 method compared with other strategies and systems for final disposal of spent nuclear fuel. An appendix to the report presents in general terms how the KBS-3 method has developed from the end of the 1970s up to today. The report is one of a number of supporting documents for SKB's applications for construction and operation of the final repository for spent nuclear fuel. In parallel with and as a basis for the present report, SKB has prepared the reports Principer, strategier och system foer slutligt omhaendertagande av anvaent kaernbraensle ('Principles, strategies and systems for final disposal of spent nuclear fuel') /Grundfelt 2010a/, Jaemfoerelse mellan KBS-3-metoden och deponering i djupa borrhaal foer slutlig foervaring av anvaent kaernbraensle ('Comparison between the KBS-3 method and deposition in deep boreholes for final disposal of spent nuclear fuel') /Grundfelt 2010b/ and Utvecklingen av KBS-3- metoden. Genomgaang av forskningsprogram, saekerhetsanalyser, myndighetsgranskningar samt SKB:s internationella forskningssamarbete ('Development of the KBS-3 method. Review of research programmes, safety assessments, regulatory reviews and SKB's international research cooperation') /SKB 2010a/. The reports are in Swedish, but contain summaries in English. The first report is an update of the comprehensive account of alternative methods presented by SKB in 2000. The second report presents a comparison between the KBS-3 method and the Deep Boreholes concept, plus a status report on research and development in the area of Deep Boreholes. The last report describes how the KBS-3 method has been developed from the end of the 1970s up to today. It further describes how the method has been further developed and refined over the years, but also what the

  16. Choice of method - evaluation of strategies and systems for disposal of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    2010-10-15

    This report deals with the question of how the Swedish spent nuclear fuel is to be disposed of. What are the requirements? What are the alternatives? In the main chapter of the report, an evaluation is made of the KBS-3 method compared with other strategies and systems for final disposal of spent nuclear fuel. An appendix to the report presents in general terms how the KBS-3 method has developed from the end of the 1970s up to today. The report is one of a number of supporting documents for SKB's applications for construction and operation of the final repository for spent nuclear fuel. In parallel with and as a basis for the present report, SKB has prepared the reports Principer, strategier och system foer slutligt omhaendertagande av anvaent kaernbraensle ('Principles, strategies and systems for final disposal of spent nuclear fuel') /Grundfelt 2010a/, Jaemfoerelse mellan KBS-3-metoden och deponering i djupa borrhaal foer slutlig foervaring av anvaent kaernbraensle ('Comparison between the KBS-3 method and deposition in deep boreholes for final disposal of spent nuclear fuel') /Grundfelt 2010b/ and Utvecklingen av KBS-3- metoden. Genomgaang av forskningsprogram, saekerhetsanalyser, myndighetsgranskningar samt SKB:s internationella forskningssamarbete ('Development of the KBS-3 method. Review of research programmes, safety assessments, regulatory reviews and SKB's international research cooperation') /SKB 2010a/. The reports are in Swedish, but contain summaries in English. The first report is an update of the comprehensive account of alternative methods presented by SKB in 2000. The second report presents a comparison between the KBS-3 method and the Deep Boreholes concept, plus a status report on research and development in the area of Deep Boreholes. The last report describes how the KBS-3 method has been developed from the end of the 1970s up to today. It further describes how the method has been further developed and

  17. The Cigar Lake uranium deposit: Analog information for Canada's nuclear fuel waste disposal concept

    International Nuclear Information System (INIS)

    Cramer, J.J.

    1995-05-01

    The Cigar Lake uranium deposit, located in northern Saskatchewan, has many features that parallel those being considered within the Canadian concept for disposal of nuclear fuel waste. The study of these natural structures and processes provides valuable insight toward the eventual design and site selection of a nuclear fuel waste repository. The main feature of this analog is the absence of any indication on the surface of the rich uranium ore 450 m below. This shows that the combination of natural barriers has been effective in isolating the uranium ore from the surface environment. More specifically, the deposit provides analog information relevant to the stability of UO 2 fuel waste, the performance of clay-based and general aspects of water-rock interaction. The main geotechnical studies on this deposit focus on the evolution of groundwater compositions in the deposit and on their redox chemistry with respect to the uranium, iron and sulphide systems. This report reviews and summarizes the analog information and data from the Cigar Lake analog studies for the processes and scenarios expected to occur in the disposal system for used nuclear fuel proposed in Canada. (author). 45 refs., 10 figs

  18. Romanian experience with rock salt characterisation methods and the implications for disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Diaconu, Daniela; Balan, Valeriu; Mirion, Ilie

    2001-01-01

    The disposal in deep geological formations as rock salt, granite or clay seems to be now the most appropriate solution for final storage of the spent fuel. At this moment, rock salt is one of the Romanian options for spent fuel disposal, but the final decision will be made only after a performance assessment of this geological formation, having as input data the specific characteristics of the salt rock. In order to provide the data requested by the safety assessment programs, the Institute for Nuclear Research - Pitesti developed complex and modern methodologies for thermodynamic parameter determination as well as studies on salt convergence and radionuclide migration. The methodologies pursued to determine those thermal properties specific for spent fuel disposal as dilatation coefficient, heat conductivity and specific heat. The convergence and migration studies pursued a better understanding of these processes, very important in the disposal safety. The paper is a review of those studies and presents the methodologies and the main results obtained on salt samples from Slanic Prahova Salt Mine. (authors)

  19. The potential for vault-induced seismicity in nuclear fuel waste disposal: experience from Canadian mines

    International Nuclear Information System (INIS)

    Martin, C.D.; Chandler, N.A.

    1996-12-01

    A seismic event which causes damage to an underground opening is called a rockburst. Practical experience indicates that these damaging seismic events are associated with deep mines where extraction ratios are greater than 0.6. For the arrangement being considered by AECL for nuclear fuel waste disposal vaults, extraction ratios, for the room and pillar design, will be less than 0.3. At this extraction ratio the stress magnitudes will not be sufficient to induce seismic events that can damage the underground openings. Documented world-wide experience shows that unless the underground opening is very close to the source of a naturally occurring seismic event, such as an earthquake, the opening will also not experience any significant damage. Backfilling a disposal vault will improve its resistance to earthquake damage. Backfilling a disposal vault will also reduce the total convergence of the openings caused by thermal loads and hence minimize the potential for thermally-induced seismic events. (author)

  20. Microbial issues pertaining to the Canadian concept for the disposal of nuclear fuel waste

    International Nuclear Information System (INIS)

    Stroes-Gascoyne, S.; West, J.M.

    1994-03-01

    AECL Research is developing a concept for the permanent disposal of nuclear fuel waste in plutonic rock of the Canadian Shield. The Federal Environmental Assessment Review Panel has issued a set of guidelines to be used by AECL Research in preparing an Environmental Impact Statement (EIS) for this concept. These guidelines require that the EIS address a number of microbiological factors and their potential to affect the integrity of the multiple barrier system on which the disposal concept is based. This report formulates a number of views and positions on microbiological factors that could influence the performance of a disposal vault in plutonic rock. Microbiological factors discussed include the presence and survival of microbes, biofilms, corrosion, biodegradation (of emplaced materials), gas production, geochemical changes, radionuclides migration, colloid formation, mutation, pathogens and methylation. Not all issues can be fully resolved with the current state of knowledge. Studies being performed to underscore and strengthen current knowledge are briefly discussed. (author). 92 refs., 1 tab

  1. Melt-Dilute Form of AI-Based Spent Nuclear Fuel Disposal Criticality Summary Report

    International Nuclear Information System (INIS)

    D. Vinson; A. Serika

    2002-01-01

    Criticality analysis of the proposed melt-dilute (MD) form of aluminum-based spent nuclear fuel (SNF), under geologic repository conditions, was performed [1] following the methodology documented in the Disposal Criticality Analysis Methodology Topical Report [2]. This methodology evaluates the potential for nuclear criticality for a waste form in a waste package. Criticality calculations show that even with waste package failure, followed by degradation of material within the waste package and potential loss of neutron absorber materials, sub-critical conditions can be readily demonstrated for the MD form of aluminum-based SNF

  2. Scenario analysis for the postclosure assessment of the Canadian concept for nuclear fuel waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Goodwin, B W; Stephens, M E; Davison, C C; Johnson, L H; Zach, R

    1994-12-01

    AECL Research has developed and evaluated a concept for disposal of Canada`s nuclear fuel waste involving deep underground disposal of the waste in intrusive igneous rock of the Canadian Shield. The postclosure assessment of this concept focusses on the effects on human health and the environment due to potential contaminant releases into the biosphere after the disposal vault is closed. Both radiotoxic and chemically toxic contaminants are considered. One of the steps in the postclosure assessment process is scenario analysis. Scenario analysis identifies factors that could affect the performance of the disposal system and groups these factors into scenarios that require detailed quantitative evaluation. This report documents a systematic procedure for scenario analysis that was developed for the postclosure assessment and then applied to the study of a hypothetical disposal system. The application leads to a comprehensive list of factors and a set of scenarios that require further quantitative study. The application also identifies a number of other factors and potential scenarios that would not contribute significantly to environmental and safety impacts for the hypothetical disposal system. (author). 46 refs., 3 tabs., 3 figs., 2 appendices.

  3. Scenario analysis for the postclosure assessment of the Canadian concept for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Goodwin, B.W.; Stephens, M.E.; Davison, C.C.; Johnson, L.H.; Zach, R.

    1994-12-01

    AECL Research has developed and evaluated a concept for disposal of Canada's nuclear fuel waste involving deep underground disposal of the waste in intrusive igneous rock of the Canadian Shield. The postclosure assessment of this concept focusses on the effects on human health and the environment due to potential contaminant releases into the biosphere after the disposal vault is closed. Both radiotoxic and chemically toxic contaminants are considered. One of the steps in the postclosure assessment process is scenario analysis. Scenario analysis identifies factors that could affect the performance of the disposal system and groups these factors into scenarios that require detailed quantitative evaluation. This report documents a systematic procedure for scenario analysis that was developed for the postclosure assessment and then applied to the study of a hypothetical disposal system. The application leads to a comprehensive list of factors and a set of scenarios that require further quantitative study. The application also identifies a number of other factors and potential scenarios that would not contribute significantly to environmental and safety impacts for the hypothetical disposal system. (author). 46 refs., 3 tabs., 3 figs., 2 appendices

  4. Radiological consequences of accidents during disposal of spent nuclear fuel in a deep borehole

    International Nuclear Information System (INIS)

    Grundfelt, Bertil

    2013-07-01

    In this report, an analysis of the radiological consequences of potential accidents during disposal of spent nuclear fuel in deep boreholes is presented. The results presented should be seen as coarse estimates of possible radiological consequences of a canister being stuck in a borehole during disposal rather than being the results of a full safety analysis. In the concept for deep borehole disposal of spent nuclear fuel developed by Sandia National Laboratories, the fuel is assumed to be encapsulated in mild steel canisters and stacked between 3 and 5 km depth in boreholes that are cased with perforated mild steel casing tubes. The canisters are joined together by couplings to form strings of 40 canisters and lowered into the borehole. When a canister string has been emplaced in the borehole, a bridge plug is installed above the string and a 10 metres long concrete plug is cast on top of the bridge plug creating a floor for the disposal of the next sting. In total 10 canister strings, in all 400 canisters, are assumed to be disposed of at between 3 and 5 kilometres depth in one borehole. An analysis of potential accidents during the disposal operations shows that the potentially worst accident would be that a canister string is stuck above the disposal zone of a borehole and cannot be retrieved. In such a case, the borehole may have to be sealed in the best possible way and abandoned. The consequences of this could be that one or more leaking canisters are stuck in a borehole section with mobile groundwater. In the case of a leaking canister being stuck in a borehole section with mobile groundwater, the potential radiological consequences are likely to be dominated by the release of the so-called Instant Release Fraction (IRF) of the radionuclide inventory, i.e. the fraction of the radionuclides that as a consequence of the in-core conditions are present in the annulus between the fuel pellets and the cladding or on the grain boundaries of the UO 2 matrix. The

  5. Radiological consequences of accidents during disposal of spent nuclear fuel in a deep borehole

    Energy Technology Data Exchange (ETDEWEB)

    Grundfelt, Bertil [Kemakta Konsult AB, Stockholm (Sweden)

    2013-07-15

    In this report, an analysis of the radiological consequences of potential accidents during disposal of spent nuclear fuel in deep boreholes is presented. The results presented should be seen as coarse estimates of possible radiological consequences of a canister being stuck in a borehole during disposal rather than being the results of a full safety analysis. In the concept for deep borehole disposal of spent nuclear fuel developed by Sandia National Laboratories, the fuel is assumed to be encapsulated in mild steel canisters and stacked between 3 and 5 km depth in boreholes that are cased with perforated mild steel casing tubes. The canisters are joined together by couplings to form strings of 40 canisters and lowered into the borehole. When a canister string has been emplaced in the borehole, a bridge plug is installed above the string and a 10 metres long concrete plug is cast on top of the bridge plug creating a floor for the disposal of the next sting. In total 10 canister strings, in all 400 canisters, are assumed to be disposed of at between 3 and 5 kilometres depth in one borehole. An analysis of potential accidents during the disposal operations shows that the potentially worst accident would be that a canister string is stuck above the disposal zone of a borehole and cannot be retrieved. In such a case, the borehole may have to be sealed in the best possible way and abandoned. The consequences of this could be that one or more leaking canisters are stuck in a borehole section with mobile groundwater. In the case of a leaking canister being stuck in a borehole section with mobile groundwater, the potential radiological consequences are likely to be dominated by the release of the so-called Instant Release Fraction (IRF) of the radionuclide inventory, i.e. the fraction of the radionuclides that as a consequence of the in-core conditions are present in the annulus between the fuel pellets and the cladding or on the grain boundaries of the UO{sub 2} matrix

  6. The economics of reprocessing versus direct disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Bunn, M.; Holdren, J.P.; Fetter, S.; Zwaan, B. van der

    2007-01-01

    The economics of reprocessing versus direct disposal of spent nuclear fuel are assessed. The break-even uranium price at which reprocessing spent nuclear fuel from existing light water reactors (LWRs) and recycling the resulting plutonium and uranium in LWRs would become economic is estimated for a wide range of reprocessing prices and other fuel cycle costs and parameters. The contribution of each fuel cycle option to the cost of electricity is also estimated. A similar analysis is performed for the breakeven uranium price at which deploying fast neutron reactors (FRs) would become competitive compared with a once-through fuel cycle in LWRs, for a range of differences in capital cost between LWRs and FRs. Available information about reprocessing prices and various other fuel cycle costs and input parameters are reviewed, as well as the quantities of uranium likely to be recoverable worldwide at a range of different possible future prices. It is concluded that the once-through fuel cycle is likely to remain significantly cheaper than reprocessing and recycling in either LWRs or FRs for at least the next 50 years. Finally, there is a discussion of how scarce and expensive repository space would have to become before separation and transmutation would be economically attractive. (author)

  7. The disposal of Canada's nuclear fuel waste: site screening and site evaluation technology

    International Nuclear Information System (INIS)

    Davison, C.C.; Brown, A.; Everitt, R.A.; Gascoyne, M.; Kozak, E.T.; Lodha, G.S.; Martin, C.D.; Soonawala, N.M.; Stevenson, D.R.; Thorne, G.A.; Whitaker, S.H.

    1994-06-01

    The concept for the disposal of Canada's nuclear fuel waste is to dispose of the waste in an underground vault, nominally at 500 m to 1000 m depth, at a suitable site in plutonic rock of the Canadian Shield. The feasibility of this concept and assessments of its impact on the environment and human health, will be documented by AECL in an Environmental Impact Statement (EIS). This report is one of nine primary references for the EIS. It describes the approach and methods that would be used during the siting stage of the disposal project to identify a preferred candidate disposal site and to confirm its suitability for constructing a disposal facility. The siting stage is divided into two distinct but closely related substages, site screening and site evaluation. Site screening would mainly involve reconnaissance investigations of siting regions of the Shield to identify potential candidate areas where suitable vault locations are likely to exist. Site screening would identify a small number of candidate areas where further detailed investigations were warranted. Site evaluation would involve progressively more detailed surface and subsurface investigations of the candidate areas to first identify potentially suitable vault locations within the candidate areas, and then characterize these potential disposal sites to identify the preferred candidate location for constructing the disposal vault. Site evaluation would conclude with the construction of exploratory shafts and tunnels at the preferred vault location, and underground characterization would be done to confirm the suitability of the preferred candidate site. An integrated program of geological, geophysical, hydrogeological, geochemical and geomechanical investigations would be implemented to obtain the geoscience information needed to assess the suitability of the candidate siting areas and candidate sites for locating a disposal vault. The candidate siting areas and candidate disposal vault sites would be

  8. An overview of microbial research related to high-level nuclear waste disposal with emphasis on the Canadian concept for the disposal of nuclear fuel waste

    International Nuclear Information System (INIS)

    Stroes-Gascoyne, S.; West, J.M.

    1995-01-01

    Current research on the effects of microbiology on nuclear waste disposal, carried out in a number of countries, is summarized. Atomic Energy of Canada Limited has developed a concept for the permanent disposal of nuclear fuel waste in Canada. A program was initiated in 1991 to address and quantify the potential effects of microbial action on the integrity of the multibarrier system on which the disposal concept is based. This microbial program focuses on answering specific questions in areas such as the survival of bacteria under relevant radiation and desiccation conditions; growth and mobility of microbes in compacted clay buffer materials and the potential consequences for container corrosion and microbial gas production; the presence and activity of microbes in deep granitic groundwaters; and the effects of biofilms on radionuclide migration in the geosphere. (author)

  9. Accelerator-driven system design concept for disposing of spent nuclear fuels

    International Nuclear Information System (INIS)

    Gohar, Y.; Cao, Y.; Kellogg, R.; Merzari, E.

    2015-01-01

    At present, the US SNF (Spent Nuclear Fuel) inventory is growing by about 2,000 metric tonnes (MT) per year from the current operating nuclear power plants to reach about 70,000 MT by 2015. This SNF inventory contains about 1% transuranics (700 MT), which has about 115 MT of minor actinides. Accelerator-driven systems utilising proton accelerators with neutron spallation targets and subcritical blankets can be utilised for transmuting these transuranics, simultaneously generating carbon free energy, and significantly reducing the capacity of the required geological repository storage facility for the spent nuclear fuels. A fraction of the SNF plutonium can be used as a MOX fuel in the current/future thermal power reactors and as a starting fuel for future fast power reactors. The uranium of the spent nuclear fuel can be recycled for use in future nuclear power plants. This paper shows that only four to five accelerator-driven systems operating for less than 33 full power years can dispose of the US SNF inventory expected by 2015. In addition, a significant fraction of the long-lived fission products will be transmuted at the same time. Each system consists of a proton accelerator with a neutron spallation target and a subcritical assembly. The accelerator beam parameters are 1 GeV protons and 25 MW beam power, which produce 3 GWt in the subcritical assembly. A liquid metal (lead or lead-bismuth eutectic) spallation target is selected because of design advantages. This target is located at the centre of the subcritical assembly to maximise the utilisation of spallation neutrons. Because of the high power density in the target material, the target has its own coolant loop, which is independent of the subcritical assembly coolant loop. Mobile fuel forms with transuranic materials without uranium are considered in this work with liquid lead or lead-bismuth eutectic as fuel carrier

  10. Natural analogs in support of the Canadian concept for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Cramer, Jan.

    1994-08-01

    The assessment of the long-term safety and performance of the Canadian concept for disposal of nuclear fuel waste is a unique and challenging undertaking, because the predictions have to be made for time periods in the range of 10 4 to 10 6 a into the future. The data used for the assessment modelling is in large part based on observations from short-term laboratory and field experiments. Natural analogs can provide a reference for the safety assessment, providing both useful data and a qualitative illustration of the interaction of processes and materials in complex natural systems. This report reviews the available natural analog information used in support of the Canadian concept, with particular emphasis on the disposal of used CANDU (CANada Deuterium Uranium) fuel. The introduction gives a definition of natural analogs and an overview of the various types of analogs and analog studies. The review is broken down into sections pertaining to the major components of the disposal system: the vault, the geosphere and the biosphere. Specific examples are given for each. In addition, a section deals with several comprehensive natural systems that contain a number of features and processes similar to the disposal concept and that are under study by a number of countries as part of their waste management programs. (author). 224 refs., 11 tabs., 2 figs

  11. Natural analogs in support of the Canadian concept for nuclear fuel waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Cramer, Jan

    1994-08-01

    The assessment of the long-term safety and performance of the Canadian concept for disposal of nuclear fuel waste is a unique and challenging undertaking, because the predictions have to be made for time periods in the range of 10{sup 4} to 10{sup 6} a into the future. The data used for the assessment modelling is in large part based on observations from short-term laboratory and field experiments. Natural analogs can provide a reference for the safety assessment, providing both useful data and a qualitative illustration of the interaction of processes and materials in complex natural systems. This report reviews the available natural analog information used in support of the Canadian concept, with particular emphasis on the disposal of used CANDU (CANada Deuterium Uranium) fuel. The introduction gives a definition of natural analogs and an overview of the various types of analogs and analog studies. The review is broken down into sections pertaining to the major components of the disposal system: the vault, the geosphere and the biosphere. Specific examples are given for each. In addition, a section deals with several comprehensive natural systems that contain a number of features and processes similar to the disposal concept and that are under study by a number of countries as part of their waste management programs. (author). 224 refs., 11 tabs., 2 figs.

  12. A review of the uncertainties in the assessment of radiological consequences of spent nuclear fuel disposal

    International Nuclear Information System (INIS)

    Wiborgh, M.; Elert, M.; Hoeglund, L.O.; Jones, C.; Grundfelt, B.; Skagius, K.; Bengtsson, A.

    1992-06-01

    Radioactive waste disposal systems for spent nuclear fuel are designed to isolate the radioactive waste from the human environment for long period of time. The isolation is provided by a combination of engineered and natural barriers. Safety assessments are performed to describe and quantify the performance of the individual barriers and the disposal system over long-term periods. These assessments will always be associated with uncertainties. Uncertainties can originate from the variability of natural systems and will also be introduced in the predictive modelling performed to quantitatively evaluate the behaviour of the disposal system as a consequence of the incomplete knowledge about the governing processes. Uncertainties in safety assessments can partly be reduced by additional measurements and research. The aim of this study has been to identify uncertainties in assessments of radiological consequences from the disposal of spent nuclear fuel based on the Swedish KBS-3 concept. The identified uncertainties have been classified with respect to their origin, i.e. in conceptual, modelling and data uncertainties. The possibilities to reduce the uncertainties are also commented upon. In assessments it is important to decrease uncertainties which are of major importance for the performance of the disposal system. These could to some extent be identified by uncertainty analysis. However, conceptual uncertainties and some type of model uncertainties are difficult to evaluate. To be able to decrease uncertainties in conceptual models, it is essential that the processes describing and influencing the radionuclide transport in the engineered and natural barriers are sufficiently understood. In this study a qualitative approach has been used. The importance of different barriers and processes are indicated by their influence on the release of some representative radionuclides. (122 refs.) (au)

  13. Interim Storage of Spent Nuclear Fuel before Final Disposal in Germany - Regulator's view

    International Nuclear Information System (INIS)

    Arens, G.; Goetz, Ch.; Geupel, Sandra; Gmal, B.; Mester, W.

    2014-01-01

    For spent nuclear fuel management in Germany the concept of dry interim storage in dual purpose casks before direct disposal is applied. The Federal Office for Radiation Protection (BfS) is the competent authority for licensing of interim storage facilities. The competent authority for surveillance of operation is the responsible authority of the respective federal state (Land). Currently operation licenses for storage facilities have been granted for a storage time of 40 years and are based on safety demonstrations for all safety issues as safe enclosure, shielding, sub-criticality and decay heat removal under consideration of operation conditions. In addition, transportability of the casks for the whole storage period has to be provided. Due to current delay in site selection and exploration of a disposal site, an extension of the storage time beyond 40 years could be needed. This will cause appropriate actions by the licensee and the competent authorities as well. A brief description of the regulatory base of licensing and surveillance of interim storage is given from the regulators view. Furthermore the current planning for final disposal of spent nuclear fuel and high level waste and its interconnections between storage and disposal concepts are shortly explained. Finally the relevant aspects for licensing of extended storage time beyond 40 years will be discussed. Current activities on this issue, which have been initiated by the Federal Government, will be addressed. On the regulatory side a review and amendment of the safety guideline for interim storage of spent fuel has been performed and the procedure of periodic safety review is being implemented. A guideline for implementing an ageing management programme is available in a draft version. Regarding safety of long term storage a study focussing on the identification and evaluation of long term effects as well as gaps of knowledge has been finished in 2010. A continuation and update is currently underway

  14. A study of the operational logistics in the disposal plant for spent nuclear fuel

    International Nuclear Information System (INIS)

    Sylvaenne, O.; Kaskinen, T.; Kuussaari, P.

    2003-02-01

    The final disposal plant for spent nuclear fuel comprises an encapsulation facility that will be built on the surface, other support activities above ground, and a repository that will be constructed deep in the bedrock. This report analyses the final repository operational logistics. The desktop research report is compiled of data taken from several existing planning reports covering the planning periods 1997-2002. The logistics specialised description of the final repository considers most areas in the daily operation of the facility. Among these are: Disposal tunnel excavation; construction and transports; Tunnel preparation for canisters; Reception of spent nuclear fuel transport casks; Encapsulation process; Preparation of bentonite blocks for canister holes, block laying; Final disposal of canisters; and Preparation of backfilling material and backfilling. The transport and handling volumes have certain cycles. Rock will be excavated during one contiguous period in 3 years, backfilling takes two weeks in a month and the deposition of canisters also two weeks. Thus the material flows vary greatly due to their cyclical nature. The transport and handling volumes are considerable, by far largest single item being excavated rock with about 5000 annual truck loads during the active excavation period, backfilling is about 1300 loads yearly at a steady pace. The report covers and summarises material flows, handling methods and equipment, buffering, storage and transports. It suggests some changes to operational procedures. Proposals have been made as to the location of the encapsulation facility and the methods of material transport. The logistical 'hot' issues, entry of the main transport ramp, rock field, rock crushing process, bentonite storage, bentonite brick production and backfiller production are all proposed to be located close to each other to minimise driving distance. It has also been proposed that the bentonite block buffer should rather be located at

  15. Generic repository concept for RBMK-1500 spent nuclear fuel disposal in crystalline rocks in Lithuania

    International Nuclear Information System (INIS)

    Poskas, P.; Brazauskaite, A.; Narkunas, E.; Smaizys, A.; Sirvydas, A.

    2006-01-01

    During 2002-2005 investigations on possibilities to dispose of spent nuclear fuel (SNF) in Lithuania were performed with support of Swedish experts. Disposal concept for RBMK-1500 SNF in crystalline rocks in Lithuania is based on Swedish KBS-3 concept with SNF emplacement into the copper canister with cast iron insert. The bentonite and its mixture with crushed rock are also foreseen as buffer and backfill material. In this paper modelling results on thermal, criticality and other important disposal characteristics for RBMK-1500 SNF fuel emplaced in copper canisters are presented. Based on thermal calculations, the distances between the canisters and between the tunnels were justified. Criticality calculations for the canister with fresh fuel with 2.8 % 235 U enrichment demonstrated that effective neutron multiplication factor k eff values are less than allowable value of 0.95. Dose calculations have shown that total equivalent dose rate from the canister with 50 years stored RBMK-1500 SNF is rather high and is defined mainly by the γ radiation. (author)

  16. Nuclear fuel waste management and disposal concept: Report. Federal environmental assessment review process

    International Nuclear Information System (INIS)

    1998-01-01

    The Canadian concept for disposing CANDU reactor waste or high-level nuclear wastes from reprocessing involves underground disposal in sealed containers emplaced in buffer-filled and sealed vaults 500--1,000 meters below ground, in plutonic rock of the Canadian Shield. This document presents the report of a panel whose mandate was to review this concept (rather than a specific disposal project at a specific site) along with a broad range of related policy issues, and to conduct that review in five provinces (including reviews with First Nations groups). It first outlines the review process and then describes the nature of the problem of nuclear waste management. It then presents an overview of the concept being reviewed, its implementation stages, performance assessment analyses performed on the concept, and implications of a facility based on that concept (health, environmental, social, transportation, economic). The fourth section examines the criteria by which the safety and acceptability of the concept should be evaluated. This is followed by a safety and acceptability evaluation from both technical and social perspectives. Section six proposes future steps for building and determining acceptability of the concept, including an Aboriginal participation process, creation of a Nuclear Fuel Waste Management Agency, and a public participation process. The final section discusses some issues outside the panel's mandate, such as energy policy and renewable energy sources. Appendices include a chronology of panel activities, a review of radiation hazards, comparison between nuclear waste management and the management of other wastes, a review of other countries' approaches to long-term management of nuclear fuel wastes, and details of a siting process proposed by the panel

  17. A proliferation-resistant closed nuclear fuel cycle with radiation-equivalent disposal of radioactive waste

    International Nuclear Information System (INIS)

    Adamov, E.O.; Gabaraev, B.A.; Ganev, I.K.; Lopatkin, A.V.; Orlov, V.V.

    1998-01-01

    The growing energy demand in the next century can be met by large-scale nuclear power that can be deployed around fast reactors operating in a closed U-Pu cycle. The main requirements to the future fuel cycle are 1) reduction of the radiation risk from radioactive waste owing to transmutation of the most hazardous long-lived actinides and fission products in reactors and due to thorough treatment of radwaste to remove these elements, with provision of a balance between the activity of waste put to final disposal and that of uranium extracted from earth; 2) no possibility to use closed cycle facilities for Pu extraction from spent fuel for the purpose of weapons production; physical protection of fuel against thefts (nonproliferation). (author)

  18. Issues related to the construction and operation of a geological disposal facility for nuclear fuel waste in crystalline rock - the Canadian experience

    Energy Technology Data Exchange (ETDEWEB)

    Allan, C.J.; Baumgartner, P.; Ohta, M.M.; Simmons, G.R.; Whitaker, S.H. [Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs

    1997-12-31

    This paper covers the overview of the Canadian nuclear fuel waste management program, the general approach to the siting, design, construction, operation and closure of a geological disposal facility, the implementing disposal, and the public involvement in implementing geological disposal of nuclear fuel waste. And two appendices are included. 45 refs., 5 tabs., 10 figs.

  19. Issues related to the construction and operation of a geological disposal facility for nuclear fuel waste in crystalline rock - the Canadian experience

    International Nuclear Information System (INIS)

    Allan, C.J.; Baumgartner, P.; Ohta, M.M.; Simmons, G.R.; Whitaker, S.H.

    1997-01-01

    This paper covers the overview of the Canadian nuclear fuel waste management program, the general approach to the siting, design, construction, operation and closure of a geological disposal facility, the implementing disposal, and the public involvement in implementing geological disposal of nuclear fuel waste. And two appendices are included. 45 refs., 5 tabs., 10 figs

  20. Survey and evaluation of handling and disposing of solid low-level nuclear fuel cycle wastes

    International Nuclear Information System (INIS)

    Mullarkey, T.B.; Jentz, T.L.; Connelly, J.M.; Kane, J.P.

    1976-10-01

    The report identifies the types and quantities of low-level solid radwaste for each portion of the nuclear fuel cycle, based on operating experiences at existing sites and design information for future installations. These facts are used to evaluate reference 1000 MWe reactor plants in terms of solid radwaste generation. The effect of waste volumes on disposal methods and land usage has also been determined, based on projections of nuclear power growth through the year 2000. The relative advantages of volume reduction alternatives are included. Major conclusions are drawn concerning available land burial space, light water reactors and fuel fabrication and reprocessing facilities. Study was conducted under the direction of an industry task force and the National Environmental Studies Project, a technical program of the Atomic Industrial Forum. Data was obtained from questionnaires sent to 8 fuel fabrication facilities, 39 reactor sites and 6 commercial waste disposal sites. Additional data were gathered from interviews with architect engineering firms, site visits, contacts with regulatory agencies and published literature

  1. Life-cycle cost analysis for Foreign Research Reactor, Spent Nuclear Fuel disposal

    International Nuclear Information System (INIS)

    Parks, P.B.; Geddes, R.L.; Jackson, W.N.; McDonell, W.R.; Dupont, M.E.; McWhorter, D.L.; Liutkus, A.S.

    1994-01-01

    DOE-EM-37 requested a life-cycle cost analysis for disposal of the Foreign Research Reactor-Spent Nuclear Fuel (FRR-SNF). The analysis was to address life-cycle and unit costs for a range of FRR-SNF elements from those currently available (6,000 elements) to the (then) bounding case (15,000 elements). Five alternative disposition strategies were devised for the FRR-SNF elements. Life-cycle costs were computed for each strategy. In addition, the five strategies were evaluated in terms of six societal and technical goals. This report summarizes the study that was originally documented to DOE-EM

  2. Limitation of the EIA Process for the assessment of nuclear fuel waste disposal in Canada

    International Nuclear Information System (INIS)

    Murphy, B.L.; Kuhn, R.G.

    1999-01-01

    The Canadian environmental impact assessment process for the Nuclear Fuel Waste Management and Disposal Concept was completed in 1994. Almost four years later, in February 1998, the Review Panel released its report. The viewpoints of those who participated in the assessment process is archived in the thousands of pages of hearing testimony, meeting transcripts and written briefs. One of the most contentious issues raised, and one that continues to plague management in Canada, is the debate surrounding how the problem of NFW waste management should be defined. The purpose of this paper is to critically assess the problem frame of the Canadian NFW management disposal concept EIS. This will be accomplished through an analysis of stakeholder participation and views, and through an evaluation of the range and nature of the information considered legitimate or constrained in the Canadian process

  3. Limitation of the EIA Process for the assessment of nuclear fuel waste disposal in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, B.L.; Kuhn, R.G. [Guelph Univ., ON (Canada). Dept. of Geography

    1999-12-01

    The Canadian environmental impact assessment process for the Nuclear Fuel Waste Management and Disposal Concept was completed in 1994. Almost four years later, in February 1998, the Review Panel released its report. The viewpoints of those who participated in the assessment process is archived in the thousands of pages of hearing testimony, meeting transcripts and written briefs. One of the most contentious issues raised, and one that continues to plague management in Canada, is the debate surrounding how the problem of NFW waste management should be defined. The purpose of this paper is to critically assess the problem frame of the Canadian NFW management disposal concept EIS. This will be accomplished through an analysis of stakeholder participation and views, and through an evaluation of the range and nature of the information considered legitimate or constrained in the Canadian process.

  4. Safety case for the disposal of spent nuclear fuel at Olkiluoto - Synthesis 2012

    International Nuclear Information System (INIS)

    2012-12-01

    TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR 2012) and application for a construction licence for a spent nuclear fuel repository. Consistent with the Government Decisions-in- Principle, this foresees a repository developed in bedrock at the Olkiluoto site according to the KBS-3 method, designed to accept spent nuclear fuel from the lifetime operations of the Olkiluoto and Loviisa reactors. Synthesis 2012 presents a synthesis of Posiva Oy's Safety Case 'TURVA-2012' portfolio. It summarises the design basis for the repository at the Olkiluoto site, the assessment methodology and key results of performance and safety assessments. It brings together all the lines of argument for safety, evaluation of compliance with the regulatory requirements, and statement of confidence in long-term safety and Posiva's safety analyses. The TURVA-2012 safety case demonstrates that the proposed repository design provides a safe solution for the disposal of spent nuclear fuel, and that the performance and safety assessments are fully consistent with all the legal and regulatory requirements related to long-term safety as set out in Government Decree 736/2008 and in guidance from the nuclear regulator - the STUK. Moreover, Posiva considers that the level of confidence in the demonstration of safety is appropriate and sufficient to submit the construction licence application to the authorities. The assessment of long-term safety includes uncertainties, but these do not affect the basic conclusions on the long-term safety of the repository. (orig.)

  5. Nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, H [Power Reactor and Nuclear Fuel Development Corp., Tokyo (Japan)

    1976-10-01

    It is expected that nuclear power generation will reach 49 million kW in 1985 and 129 million kW in 1995, and the nuclear fuel having to be supplied and processed will increase in proportion to these values. The technical problems concerning nuclear fuel are presented on the basis of the balance between the benefit for human beings and the burden on the human beings. Recently, especially the downstream of nuclear fuel attracts public attention. Enriched uranium as the raw material for light water reactor fuel is almost monopolized by the U.S., and the technical information has not been published for fear of the diversion to nuclear weapons. In this paper, the present situations of uranium enrichment, fuel fabrication, transportation, reprocessing and waste disposal and the future problems are described according to the path of nuclear fuel cycle. The demand and supply of enriched uranium in Japan will be balanced up to about 1988, but afterwards, the supply must rely upon the early establishment of the domestic technology by centrifugal separation method. No problem remains in the fabrication of light water reactor fuel, but for the fabrication of mixed oxide fuel, the mechanization of the production facility and labor saving are necessary. The solution of the capital risk for the construction of the second reprocessing plant is the main problem. Japan must develop waste disposal techniques with all-out efforts.

  6. From the reactor to waste disposal: the back-end of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Madic, C.

    1988-05-01

    The oxide fuels discharged from LWRs represent the bulk of spent fuels to be managed. For a 1 GWe LWR about 27 tonnes of spent fuels are discharged each year. This makes the total amount of spent LWR oxide fuels discharged worldwide in 1986 close to 4500 tonnes. For France, 750 tonnes of spent oxide fuels were discharged in 1986. Three alternatives are available: final disposal, interim storage, and reprocessing. This paper focusses on reprocessing option. The reprocessing is based on the PUREX Process comprising: 1/ fuel dissolution in nitric acid after shearing the fuel assembly, 2/ separation of uranium and plutonium by TBP extraction. After purification, the major actinides can be reused. A wide gap exists today between the amount of fuels discharged from LWRs and the reprocessing capacities. France has the broadest experience in reprocessing commercial LWR oxide fuels, with more than 2200 tonnes already reprocessed at La Hague. This plant will have a total reprocessing capacity of 1600 t/y in the early nineties. The minor actinides present in the spent fuels, neptunium, americium and curium, will be packaged with the fission products in glass blocks. For a 1 Gwe LWR, about 3.5 m 3 of vitrified HAW and 83 m 3 of MAW will be produced each year. All the wastes produced during reprocessing operations with an alpha activity > 0.1 Ci/t will be stored in deep geological repositories in the future. Studies are underway to determine the ideal geological sites. The solution to this problem is undoubtedly a key to the progress in the production of nuclear electricity

  7. Source term for the bounding assessment of the Canadian nuclear fuel waste disposal concept

    International Nuclear Information System (INIS)

    Flavelle, P.

    1996-02-01

    This is the second in a series to derive the bounds of the post-closure hazard of the Canadian nuclear fuel waste disposal concept, based on the premise that it is unnecessary to predict accurately the real hazard if the bounding hazard can be shown to be acceptable. In this report a reference used (Bruce A fuel, 865 GJ/kgU average burnup) is used to derive the source term for contaminant releases from the emplacement canisters. This requires development of a container failure function which defines the age of the fuel when the canister is perforated and flooded. The source term is expressed as the time-dependent fractional release rate from the used fuel or as the time-dependent contaminant concentrations in the canister porewater. It is derived as the superposition of an instant release, comprising the upper bound of the gap and grain boundary inventory in the used fuel, and the long-term dissolution of the used fuel matrix. Several dissolution models (stoichiometric dissolution/preferential leaching) under different conditions (matrix solubility limited/ unlimited; oxidizing/ reducing solubility limits; groundwater flow/ no flow) are evaluated and the one resulting in the highest release rate/ highest porewater concentration is adopted as the bounding case. Comparisons between the models are made on the basis of the potential ingestion hazard of the canister porewater, to account for differences in the hazard of different radionuclides. (author) 20 refs., 4 tabs., 9 figs

  8. Galvanic corrosion of lead coupled with titanium for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Mani Mathew, P.; Krueger, P.A.

    1989-01-01

    In the Canadian Nuclear Fuel Waste Management Program, metals and alloys with low melting points are being evaluated for their potential application as cast matrices within used-fuel immobilization containers. This paper describes studies of galvanic corrosion between lead, candidate matrix metal and ASTM Grade-2 titanium, a candidate container-shell material. The studies were conducted under conditions that simulate a breached disposal container surrounded by a bentonite/sand mixture and emplaced in a granitic rock formation at a depth of 500-1000 m. The fractional factorial statistical design of Box Behnken was used in the tests, which covered a wide range of potential conditions that could occur in a nuclear-waste disposal vault. Test temperatures ranged from 293 to 423 K. Ionic strength and oxygen content of the simulated groundwater varied from 0.0015 to 1.37 mol and 0.02 to 8.0 mg/l, respectively. A mathematical expression was derived for the lead corrosion rates as a function of the independent variables: temperature, ionic strength, and oxygen content. This expression was used to calculate the lifetime of the additional barrier that a 25-mm thick lead layer could provide to a titanium container that eventually perforates by erosion. The results show that at least 860 years of additional barrier life could be provided by the lead matrix

  9. The potential for microbial life in a Canadian high-level nuclear fuel waste disposal vault

    International Nuclear Information System (INIS)

    Stroes-Gascoyne, S.

    1989-12-01

    Recent studies have concluded that microbial contamination of a nuclear fuel waste disposal vault is inevitable. Factors that will affect the development of substantial population of micro-organisms include: physiological tolerance of microbes; fluid movement in a vault; availability of nutrients; and availability of energy sources. It is difficult to resolve whether microbial growth will either positively or negatively affect the performance of a vault. One of the necessary steps towards ultimately answering this question is to assess the potential for microbial growth in a disposal vault, based on a nutrient and energy budget. This report gives a quantitative (but conservative) inventory of nutrients and potential energy sources present in a Canadian nuclear fuel waste vault, which hypothetically could support the growth of micro-organisms. Maximum population densities are calculated based on these inventories and assuming that all conditions for microbial growth are optimal, although this will certainly not be the case. Laboratory studies under the vault-relevant conditions are being performed to put realistic boundaries on the calculated numbers. Initial results from these studies, combined with data from a natural analogue site indicate that the calculated population densities could be overestimated by four to five orders of magnitude. Limited data show no effect of the presence of microbes on the transport of Tc, I, and Sr in backfill sand columns. Additional work is needed to address transport effects on buffer and backfill clay columns

  10. Chemical and mineralogical aspects of water-bentonite interaction in nuclear fuel disposal conditions

    International Nuclear Information System (INIS)

    Melamed, A.; Pitkaenen, P.

    1996-01-01

    In the field of nuclear fuel disposal, bentonite has been selected as the principal sealing and buffer material for placement around waste canisters, forming both a mechanical and chemical barrier between the radioactive waste and the surrounding ground water. Ion exchange and mineral alteration processes were investigated in a laboratory study of the long-term interaction between compacted Na-bentonite (Volclay MX-80) and ground water solutions, conducted under simulated nuclear fuel disposal conditions. The possible alteration of montmorillonite into illite has been a major object of the mineralogical study. However, no analytical evidence was found, that would indicate the formation of this non-expandable clay type. Apparently, the change of montmorillonite from Na- to Ca-rich was found to be the major alteration process in bentonite. In the water, a concentration decrease in Ca, Mg, and K, and an increase in Na, HCO 3 and SO 4 were recorded. The amount of calcium ions available in the water was considered insufficient to account for the recorded formation of Ca-montmorillonite. It is therefore assumed that the accessory Ca-bearing minerals in bentonite provide the fundamental source of these cations, which exchange with sodium during the alteration process. (38 refs.)

  11. Multi-purpose canisters as an alternative for storage, transportation, and disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Hollaway, W.R.; Rozier, R.; Nitti, D.A.; Williams, J.R.

    1993-01-01

    A study was conducted to assess the feasibility of using multi-purpose canisters to handle spent nuclear fuel throughout the Civilian Radioactive Waste Management System. Multi-purpose canisters would be sealed, metallic containers maintaining multiple spent fuel assemblies in a dry, inert environment and overpacked separately and uniquely for the various system elements of storage, transportation, and disposal. Using five implementation scenarios, the multi-purpose canister was evaluated with regard to several measures of effectiveness, including number of handlings, radiation exposure, cost, schedule and licensing considerations, and public perception. Advantages and disadvantages of the multi-purpose canister were identified relative to the current reference system within each scenario, and the scenarios were compared to determine the most effective method of implementation

  12. Assessing risks to fish populations near a proposed disposal facility for used nuclear fuel

    International Nuclear Information System (INIS)

    Hart, D.; Miesenheimer, P.; Hull, R.

    1995-01-01

    The concept of used nuclear fuel disposal in the Canadian Shield is currently undergoing a federal environmental assessment review process. As part of this review, potential risks to brook trout populations in the vicinity of such an underground repository were considered. Chemical fate, transport and exposure models have been utilized to estimate the dose rates from released radionuclides and other fuel constituents, and these likely will not be sufficient to harm fish in nearby streams. However, other stressors such as habitat alteration (e.g., loss of upwelling) and/or fishing pressure associated with increased public access could have significant population impacts if the site is located in a pristine northern region. Population models are utilized to explore the risks of local population reduction for different combinations of fishing pressure and habitat degradation

  13. Evaluation of phyllosilicates as a buffer component in the disposal of nuclear fuel waste

    International Nuclear Information System (INIS)

    Oscarson, D.W.; Cheung, S.C.H.

    1983-12-01

    The disposal concept now being assessed in the Canadian Nuclear Fuel Waste Management program entails the emplacement of containers with used fuel or fuel recycle waste deep in a stable plutonic formation, possibly in the Canadian Shield. One of the engineered barriers to radionuclide movement from the waste containers to the biosphere is a buffer material placed between the containers and the surrounding rock mass. An effective buffer material should have a combination of the following properties: low hydraulic conductivity and diffusivity for water and dissolved chemical species, a high sorption capacity for radionuclides, high thermal conductivity, sufficient physical strength to support the waste containers, and long-term stability under the conditions existing in a disposal vault. This report evaluates phyllosilicates for their effectiveness as potential buffer components. It concludes that bentonite, because of its high swelling potential, low hydraulic conductivity, low effective porosity, and high sorption capacity for many radionuclides, would be the most effective phyllosilicate for use as a buffer component

  14. Deep geological disposal system development; mechanical structural stability analysis of spent nuclear fuel disposal canister under the internal/external pressure variation

    Energy Technology Data Exchange (ETDEWEB)

    Kwen, Y. J.; Kang, S. W.; Ha, Z. Y. [Hongik University, Seoul (Korea)

    2001-04-01

    This work constitutes a summary of the research and development work made for the design and dimensioning of the canister for nuclear fuel disposal. Since the spent nuclear fuel disposal emits high temperature heats and much radiation, its careful treatment is required. For that, a long term(usually 10,000 years) safe repository for spent fuel disposal should be securred. Usually this repository is expected to locate at a depth of 500m underground. The canister construction type introduced here is a solid structure with a cast iron insert and a corrosion resistant overpack, which is designed for spent nuclear fuel disposal in a deep repository in the crystalline bedrock, which entails an evenly distributed load of hydrostatic pressure from undergroundwater and high pressure from swelling of bentonite buffer. Hence, the canister must be designed to withstand these high pressure loads. Many design variables may affect the structural strength of the canister. In this study, among those variables array type of inner baskets and thicknesses of outer shell and lid and bottom are tried to be determined through the mechanical linear structural analysis, thicknesses of outer shell is determined through the nonlinear structural analysis, and the bentonite buffer analysis for the rock movement is conducted through the of nonlinear structural analysis Also the thermal stress effect is computed for the cast iron insert. The canister types studied here are one for PWR fuel and another for CANDU fuel. 23 refs., 60 figs., 23 tabs. (Author)

  15. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Features, events and processes 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    Features, Events and Processes sits within Posiva Oy's Safety Case 'TURVA-2012' portfolio and has the objective of presenting the main features, events and processes (FEPs) that are considered to be potentially significant for the long-term safety of the planned KBS-3V repository for spent nuclear fuel at Olkiluoto. The primary purpose of this report is to support Performance Assessment, Formulation of Radionuclide Release Scenarios, Assessment of the Radionuclide Release Scenarios for the Repository System and Biosphere Assessment by ensuring that the scenarios are comprehensive and take account of all significant FEPs. The main FEPs potentially affecting the disposal system are described for each relevant subsystem component or barrier (i.e. the spent nuclear fuel, the canister, the buffer and tunnel backfill, the auxiliary components, the geosphere and the surface environment). In addition, a small number of external FEPs that may potentially influence the evolution of the disposal system are described. The conceptual understanding and operation of each FEP is described, together with the main features (variables) of the disposal system that may affect its occurrence or significance. Olkiluoto-specific issues are considered when relevant. The main uncertainties (conceptual and parameter/data) associated with each FEP that may affect understanding are also documented. Indicative parameter values are provided, in some cases, to illustrate the magnitude or rate of a process, but it is not the intention of this report to provide the complete set of numerical values that are used in the quantitative safety assessment calculations. Many of the FEPs are interdependent and, therefore, the descriptions also identify the most important direct couplings between the FEPs. This information is used in the formulation of scenarios to ensure the conceptual models and calculational cases are both comprehensive and representative. (orig.)

  16. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Features, events and processes 2012

    International Nuclear Information System (INIS)

    2012-12-01

    Features, Events and Processes sits within Posiva Oy's Safety Case 'TURVA-2012' portfolio and has the objective of presenting the main features, events and processes (FEPs) that are considered to be potentially significant for the long-term safety of the planned KBS-3V repository for spent nuclear fuel at Olkiluoto. The primary purpose of this report is to support Performance Assessment, Formulation of Radionuclide Release Scenarios, Assessment of the Radionuclide Release Scenarios for the Repository System and Biosphere Assessment by ensuring that the scenarios are comprehensive and take account of all significant FEPs. The main FEPs potentially affecting the disposal system are described for each relevant subsystem component or barrier (i.e. the spent nuclear fuel, the canister, the buffer and tunnel backfill, the auxiliary components, the geosphere and the surface environment). In addition, a small number of external FEPs that may potentially influence the evolution of the disposal system are described. The conceptual understanding and operation of each FEP is described, together with the main features (variables) of the disposal system that may affect its occurrence or significance. Olkiluoto-specific issues are considered when relevant. The main uncertainties (conceptual and parameter/data) associated with each FEP that may affect understanding are also documented. Indicative parameter values are provided, in some cases, to illustrate the magnitude or rate of a process, but it is not the intention of this report to provide the complete set of numerical values that are used in the quantitative safety assessment calculations. Many of the FEPs are interdependent and, therefore, the descriptions also identify the most important direct couplings between the FEPs. This information is used in the formulation of scenarios to ensure the conceptual models and calculational cases are both comprehensive and representative. (orig.)

  17. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Features, events and processes 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    Features, Events and Processes sits within Posiva Oy's Safety Case 'TURVA-2012' portfolio and has the objective of presenting the main features, events and processes (FEPs) that are considered to be potentially significant for the long-term safety of the planned KBS-3V repository for spent nuclear fuel at Olkiluoto. The primary purpose of this report is to support Performance Assessment, Formulation of Radionuclide Release Scenarios, Assessment of the Radionuclide Release Scenarios for the Repository System and Biosphere Assessment by ensuring that the scenarios are comprehensive and take account of all significant FEPs. The main FEPs potentially affecting the disposal system are described for each relevant subsystem component or barrier (i.e. the spent nuclear fuel, the canister, the buffer and tunnel backfill, the auxiliary components, the geosphere and the surface environment). In addition, a small number of external FEPs that may potentially influence the evolution of the disposal system are described. The conceptual understanding and operation of each FEP is described, together with the main features (variables) of the disposal system that may affect its occurrence or significance. Olkiluoto-specific issues are considered when relevant. The main uncertainties (conceptual and parameter/data) associated with each FEP that may affect understanding are also documented. Indicative parameter values are provided, in some cases, to illustrate the magnitude or rate of a process, but it is not the intention of this report to provide the complete set of numerical values that are used in the quantitative safety assessment calculations. Many of the FEPs are interdependent and, therefore, the descriptions also identify the most important direct couplings between the FEPs. This information is used in the formulation of scenarios to ensure the conceptual models and calculational cases are both comprehensive and representative. (orig.)

  18. Criticality safety considerations in the geologic disposal of spent nuclear fuel assemblies

    International Nuclear Information System (INIS)

    Gore, B.F.; McNair, G.W.; Heaberlin, S.W.

    1980-05-01

    Features of geologic disposal which hamper the demonstration that criticality cannot occur therein include possible changes of shape and form, intrusion of water as a neutron moderator, and selective leaching of spent fuel constituents. If the criticality safety of spent fuel disposal depends on burnup, independent measurements verifying the burnup should be performed prior to disposal. The status of nondestructive analysis method which might provide such verification is discussed. Calculations were performed to assess the potential for increasing the allowed size of a spent fuel disposal canister if potential water intrusion were limited by close-packing the enclosed rods. Several factors were identified which severely limited the potential of this application. The theoretical limit of hexagonal close-packing cannot be achieved due to fuel rod bowing. It is concluded that disposal canisters should be sized on the basis of assumed optimum moderation. Several topics for additional research were identified during this limited study

  19. Nuclear Dynamics Consequence Analysis (NDCA) for the Disposal of Spent Nuclear Fuel in an Underground Geologic Repository - Volume 3: Appendices

    International Nuclear Information System (INIS)

    Taylor, L.L.; Wilson, J.R.; Sanchez, L.C.; Aguilar, R.; Trellue, H.R.; Cochrane, K.; Rath, J.S.

    1998-01-01

    The United States Department of Energy Office of Environmental Management's (DOE/EM's) National Spent Nuclear Fuel Program (NSNFP), through a collaboration between Sandia National Laboratories (SNL) and Idaho National Engineering and Environmental Laboratory (INEEL), is conducting a systematic Nuclear Dynamics Consequence Analysis (NDCA) of the disposal of SNFs in an underground geologic repository sited in unsaturated tuff. This analysis is intended to provide interim guidance to the DOE for the management of the SNF while they prepare for final compliance evaluation. This report presents results from a Nuclear Dynamics Consequence Analysis (NDCA) that examined the potential consequences and risks of criticality during the long-term disposal of spent nuclear fuel owned by DOE-EM. This analysis investigated the potential of post-closure criticality, the consequences of a criticality excursion, and the probability frequency for post-closure criticality. The results of the NDCA are intended to provide the DOE-EM with a technical basis for measuring risk which can be used for screening arguments to eliminate post-closure criticality FEPs (features, events and processes) from consideration in the compliance assessment because of either low probability or low consequences. This report is composed of an executive summary (Volume 1), the methodology and results of the NDCA (Volume 2), and the applicable appendices (Volume 3)

  20. The disposal of Canada's nuclear fuel waste: the biosphere model, BIOTRAC, for postclosure assessment

    International Nuclear Information System (INIS)

    Davis, P.A.; Zach, R.; Stephens, M.E.; Amiro, B.D.; Bird, G.A.; Reid, J.A.K.; Sheppard, M.I.; Sheppard, S.C.; Stephenson, M.

    1993-01-01

    The nuclear fuel waste management concept of Canada calls for disposal of the waste in a vault mined deep in plutonic rock of the Canadian Shield. The technical feasibility of this concept, and its impact on the environment and human health, will be documented in an Environmental Impact statement (EIS) by AECL. The present report is one of nine EIS primary references. The report describes the BIOTRAC model, which is used to trace nuclide movement from the geosphere through the biosphere and to calculate time-dependent environmental concentrations and radiological doses to humans and other biota for the postclosure phase. These concentrations and doses are crucial for evaluating the safety and environmental acceptability of the concept in terms of chemical and radiological toxicity. BIOTRAC was developed specifically to assess the impacts of a used-fuel disposal vault. It is a comprehensive, generic model with distributed or probabilistic parameter values to account for spatial and temporal variability and uncertainty. It is composed of four separate but closely linked submodels representing surface waters, soils, the atmosphere and the food chain. It also includes a unique model for predicting radiological doses to non-human biota, represented by generic target organisms. The mathematical formulation of each submodel is derived in detail and interpreted physically, and all the assumptions are fully evaluated and discussed. It is shown how the parameter values and distributions adopted for each submodel are derived from the available data. The interfaces between the submodels, and between BIOTRAC and the geosphere model, are presented in detail. Fluctuations in the physical state of the biosphere are accounted for through the parameter distributions. Major environmental changes, such as those caused by continental glaciation, are addressed quantitatively and through reasoned arguments, which indicate that radiological doses to humans will not increase suddenly or

  1. Cost estimations for deep disposal of spent nuclear fuels; Kostnadsberaekning av djupfoervaring av det anvanda kaernbraenslet

    Energy Technology Data Exchange (ETDEWEB)

    Palmqvist, K.; Wallroth, T. [BERGAB - Berggeologiska Undersoekningar AB, Goeteborg (Sweden); Green, L.; Joensson, Lars [Peab Berg AB, Goeteborg (Sweden)

    1999-10-01

    According to the Act on the Financing of Future Expenses for Spent Nuclear Fuel etc. (Financing Act), the Swedish Nuclear Fuel and Waste Management Co. (SKB) must submit, every year, to the Swedish Nuclear Power Inspectorate (SKI), a cost estimate for the management of spent nuclear fuel and for the decommissioning and dismantling of the nuclear power plants. After SKI has examined and evaluated the cost estimates, SKI must submit a proposal to the Government concerning the fee which should be paid by the nuclear power companies per kWh of generated electricity. According to the Financing Act, the reactor owners must pledge collateral in the event that the accumulated fees should be found to be insufficient as a result of early closure of reactors or as a result of underestimating the future expenses of managing the spent nuclear fuel and of decommissioning and dismantling the reactors. The future total expenses resulting from the Financing Act are estimated at about SEK 48 billion at the January 1998 price level. Of this amount, the cost of the final disposal of spent nuclear fuel in SKB's programme is expected to amount to about SEK 12 billion. SKB's estimate comprises the cost of siting, construction and operation of a deep repository for spent nuclear fuel, based on the KBS-3 concept, and a rock cavern for other long-lived waste which SKB plans to locate next to the spent fuel repository. The cost estimate also includes the dismantling and closure of the facility once all of the fuel and the long-lived waste are deposited. The calculations are based on all of the fuel, which will be generated through the operation of the 12 Swedish reactors during a period of 25 years and for every additional year of operation. At the beginning of 1998, SKI commissioned BERGAB to evaluate the cost estimate for the deep disposal of the spent nuclear fuel. The task was divided into two stages, namely a study which was submitted in June 1998 concerning the technical

  2. Geologic disposal as optimal solution of managing the spent nuclear fuel and high-level radioactive waste

    International Nuclear Information System (INIS)

    Ilie, P.; Didita, L.; Ionescu, A.; Deaconu, V.

    2002-01-01

    To date there exist three alternatives for the concept of geological disposal: 1. storing the high-level waste (HLW) and spent nuclear fuel (SNF) on ground repositories; 2. solutions implying advanced separation processes including partitioning and transmutation (P and T) and eventual disposal in outer space; 3. geological disposal in repositories excavated in rocks. Ground storing seems to be advantageous as it ensures a secure sustainable storing system over many centuries (about 300 years). On the other hand ground storing would be only a postponement in decision making and will be eventually followed by geological disposal. Research in the P and T field is expected to entail a significant reduction of the amount of long-lived radioactive waste although the long term geological disposal will be not eliminated. Having in view the high cost, as well as the diversity of conditions in the countries owning power reactors it appears as a reasonable regional solution of HLW disposal that of sharing a common geological disposal. In Romania legislation concerning of radioactive waste is based on the Law concerning Spent Nuclear Fuel and Radioactive Waste Management in View of Final Disposal. One admits at present that for Romania geological disposal is not yet a stressing issue and hence intermediate ground storing of SNF will allow time for finding a better final solution

  3. The impact of a final disposal facility for spent nuclear fuel on a municipality's image

    International Nuclear Information System (INIS)

    Kankaanpaeae, H.; Haapavaara, L.; Lampinen, T.

    1999-02-01

    The study comprised on one hand a nationwide telephone interview (totally 800 interviews) aimed at mapping out the current image of possible host municipalities to a final disposal facility for spent nuclear fuel, and on the other hand some group interviews of people of another parish but of interest from the municipalities' point of view. The purpose of these group interviews was the same as that of the telephone interview, i.e. to find out what kind of an impact locating a final disposal facility of spent nuclear fuel in a certain municipality would have on the host municipality's image. Because the groups interviewed were selected on different grounds the results of the interviews are not fully comparable. The most important result of the study is that the current attitude towards a final disposal facility for spent nuclear fuel is calm and collected and that the matter is often considered from the standpoint of an outsider. The issue is easily ignored, classified as a matter 'which does not concern me', provided that the facility will not be placed too near one's own home. Among those interviewed the subject seemed not to be of any 'great interest and did not arouse spontaneous feelings for or against'. There are, however, deeply rooted beliefs concerning the facility and quite strong negative and positive attitudes towards it. The facility itself and the associated decision-making procedure arouse many questions, which at present to a large extent are still unexpressed because the subject is considered so remote. It is, however, necessary to give concrete answers to the questions because this makes it possible for people to relate the issue to daily life. It is further important that things arousing fear and doubts also can be discussed because a silence in this respect only emphasizes their importance. The attitude towards the facility is varying. On one hand there are economic and technical factors: the probable economic benefit from it, the obligation to

  4. An approach to applying quality assurance to nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Cooper, R.B.; Abel, R.

    1996-12-01

    An approach to developing and applying a quality assurance program for a nuclear fuel waste disposal facility is described. The proposed program would be based on N286-series standards used for quality assurance programs in nuclear power plants, and would cover all aspects of work across all stages of the project, from initial feasibility studies to final closure of the vault. A quality assurance manual describing the overall quality assurance program and its elements would be prepared at the outset. Planning requirements of the quality assurance program would be addressed in a comprehensive plan for the project. Like the QA manual, this plan would be prepared at the outset of the project and updated at each stage. Particular attention would be given to incorporating the observational approach in procedures for underground engineering, where the ability to adapt designs and mining techniques to changing ground conditions would be essential. Quality verification requirements would be addressed through design reviews, peer reviews, inspections and surveillance, equipment calibration and laboratory analysis checks, and testing programs. Regular audits and program reviews would help to assess the state of implementation, degree of conformance to standards, and effectiveness of the quality assurance program. Audits would be particularly useful in assessing the quality systems of contractors and suppliers, and in verifying the completion of work at the end of stages. Since a nuclear fuel waste disposal project would span a period of about 90 years, a key function of the quality assurance program would be to ensure the continuity of knowledge and the transfer of experience from one stage to another This would be achieved by maintaining a records management system throughout the life of the project, by ensuring that work procedures were documented and kept current with new technologies and practices, and by instituting training programs that made use of experience gained

  5. Safety case for the disposal of spent nuclear fuel at Olkiluoto - Synthesis 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR 2012) and application for a construction licence for a spent nuclear fuel repository. Consistent with the Government Decisions-in- Principle, this foresees a repository developed in bedrock at the Olkiluoto site according to the KBS-3 method, designed to accept spent nuclear fuel from the lifetime operations of the Olkiluoto and Loviisa reactors. Synthesis 2012 presents a synthesis of Posiva Oy's Safety Case 'TURVA-2012' portfolio. It summarises the design basis for the repository at the Olkiluoto site, the assessment methodology and key results of performance and safety assessments. It brings together all the lines of argument for safety, evaluation of compliance with the regulatory requirements, and statement of confidence in long-term safety and Posiva's safety analyses. The TURVA-2012 safety case demonstrates that the proposed repository design provides a safe solution for the disposal of spent nuclear fuel, and that the performance and safety assessments are fully consistent with all the legal and regulatory requirements related to long-term safety as set out in Government Decree 736/2008 and in guidance from the nuclear regulator - the STUK. Moreover, Posiva considers that the level of confidence in the demonstration of safety is appropriate and sufficient to submit the construction licence application to the authorities. The assessment of long-term safety includes uncertainties, but these do not affect the basic conclusions on the long-term safety of the repository. (orig.)

  6. Department of Energy report on fee for spent nuclear fuel storage and disposal services

    International Nuclear Information System (INIS)

    1980-10-01

    Since the July 1978 publication of an estimated fee for storage and disposal, several changes have occurred in the parameters which impact the spent fuel fee. DOE has mounted a diversified program of geologic investigations that will include locating and characterizing a number of potential repository sites in a variety of different geologic environments with diverse rock types. As a result, the earliest operation date of a geologic repository is now forecast for 1997. Finally, expanded spent fuel storage capabilities at reactors have reduced the projected quantities of fuel to be stored and disposed of. The current estimates for storage and disposal are presented. This fee has been developed from DOE program information on spent fuel storage requirements, facility availability, facility cost estimates, and research and development programs. The discounted cash flow technique has used the most recent estimates of cost of borrowing by the Federal Government. This estimate has also been used in calculating the Federal charge for uranium enrichment services. A prepayment of a percentage of the storage portion of the fee is assumed to be required 5 years before spent fuel delivery. These funds and the anticipated $300 million in US Treasury borrowing authority should be sufficient to finance the acquisition of storage facilities. Similarly, a prepayment of a percentage of the disposal portion would be collected at the same time and would be used to offset disposal research and development expenditures. The balance of the storage and disposal fees will be collected upon spent fuel delivery. If disposal costs are different from what was estimated, there will be a final adjustment of the disposal portion of the fee when the spent fuel is shipped from the AFR for permanent disposal. Based on current spent fuel storage requirements, at least a 30 percent prepayment of the fee will be required

  7. Comparison between the KBS-3 method and the deep borehole for final disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Grundfelt, Bertil

    2010-09-01

    In this report a comparison is made between disposal of spent nuclear fuel according to the KBS-3 method with disposal in very deep boreholes. The objective has been to make a broad comparison between the two methods, and by doing so to pinpoint factors that distinguish them from each other. The ambition has been to make an as fair comparison as possible despite that the quality of the data of relevance is very different between the methods

  8. The disposal of Canada's nuclear fuel waste: the vault model for postclosure assessment

    International Nuclear Information System (INIS)

    Johnson, L.H.; LeNeveu, D.M.; Shoesmith, D.W.; Oscarson, D.W.; Gray, M.N.; Lemire, R.J.; Garisto, N.C.

    1994-01-01

    The concept for disposal of Canada's nuclear fuel waste involves emplacing the waste in a vault excavated at a depth of 500 to 1000 m in plutonic rock of thc Canadian Shield. The solid waste would be isolated from the biosphere by a multibarrier system consisting of engineered barriers, including corrosion-resistant containers and clay- and cement-based sealing materials, and the natural barrier provided by the massive geological formation. The technical feasibility of this concept, and its impact on the environment and human health, is being documented in an Environmental Impact Statement (EIS) that will be submitted for review under the federal Environmental Assessment and Review Process. The present report is one of nine EIS primary references. The report describes the vault model, which is used to calculate the time-dependent release of radioactive and non-radioactive contaminants from the engineered barrier system (vault) into the surrounding rock (geosphere). The model calculations presented are for a specific reference vault design that comprises used CANDU (CANada Deuterium Uranium) fuel bundles in Grade-2 titanium containers, which would be emplaced in boreholes in the floor of a mined excavation located at a depth of 500 m in plutonic rock. The containers would be surrounded by a compacted buffer material that is a mixture of 50 wt. % sand and 50 wt. % bentonite. Disposal rooms and tunnels would be sealed with a layer of backfill mixture composed of 25 % glacial lake clay and 75% crushed granite and an overlying layer of buffer material. The vault model is a computer code that calculates the failure times of titanium containers, the rate of release of radionuclides from used-fuel bundles into the groundwater that would flow into the failed containers, and the rate of transport of radionuclides from the fuel through the groundwater-saturated buffer and backfill materials and into the surrounding rock. The vault model uses distributed or probabilistic

  9. Corrosion of copper containers prior to saturation of a nuclear fuel waste disposal vault

    International Nuclear Information System (INIS)

    King, F.; Kolar, M.

    1997-12-01

    The buffer material surrounding the containers in a Canadian nuclear fuel waste disposal vault will partially desiccate as a result of the elevated temperature at the container surface. This will lead to a period of corrosion in a moist air atmosphere. Corrosion will either take the form of slow oxidation if the container surface remains dry or aqueous electrochemical corrosion if the surface is wetted by a thin liquid film. The relevant literature is reviewed, from which it is concluded that corrosion should be uniform in nature, except if the surface is wetted, in which case localized corrosion is a possibility. A quantitative analysis of the extent and rate of uniform corrosion during the unsaturated period is presented. Two bounding cases are considered: first, the case of slow oxidation in moist air following either logarithmic or parabolic oxide-growth kinetics and, second, the case of electrochemically based corrosion occurring in a thin liquid film uninhibited by the growth of corrosion products. (author)

  10. Progress in welding studies for Canadian nuclear fuel waste disposal containers

    International Nuclear Information System (INIS)

    Maak, P.Y.Y.

    1985-11-01

    This report describes the progress in the development of closure-welding technology for Canadian nuclear fuel waste disposal containers. Titanium, copper and Inconel 625 are being investigated as candidate materials for fabrication of these containers. Gas-tungsten-arc welding, gas metal-arc-welding, resistance-heated diffusion bonding and electron beam welding have been evaluated as candidate closure welding processes. Characteristic weldment properties, relative merits of welding techniques, suitable weld joint configurations and fit-up tolerances, and welding parameter control ranges have been identified for various container designs. Furthermore, the automation requirements for candidate welding processes have been assessed. Progress in the development of a computer-controlled remote gas-shielded arc welding system is described

  11. The socio-economic impact assessment for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Tamm, J.; Wlodarczyk, T.

    1992-01-01

    The concept for disposal of Canada's nuclear fuel waste will undergo public scrutiny as it is examined under the Canadian Environmental Assessment and Review Process (EARP). This process presents a number of challenges in preparing the socio-economic impact assessment (SEIA) component of an Environment Impact Statement. These challenges relate to defining the scope of the SEIA, adapting site-specific methodologies to an assessment of a concept, and addressing evolving public concerns and issues. This paper reports that in meeting these challenges a generic process-oriented SEIA has been developed that emphasizes the importance of defining policies and processes to manage socio-economic impacts. In addition, public involvement and attitude research has facilitated the assessment of the concept at the societal level

  12. Potential effects of climatic change on radiological doses from disposal of Canadian nuclear fuel waste

    International Nuclear Information System (INIS)

    Amiro, B.D.

    1997-01-01

    The environmental assessment of deep geologic disposal of Canadian nuclear fuel waste considers many processes that could affect radionuclide transport to humans over thousands of years. Climatic change is an important feature that will occur over these long times. Glaciation will likely occur within the next 100,000 years over much of Canada, and its impact on radiological doses has been assessed previously. In the present study, we investigate the potential effect of short- term climatic change, usually associated with global warming caused by increases in atmospheric trace gases. We study the main biosphere transport pathways causing a radiological dose to humans from 129 I, which is the most important radionuclide in disposal of Canadian used nuclear fuel. Irrigation of a garden with contaminated well water is the main pathway and it can be affected by changes in temperature and precipitation. A cold, wet climate decreases the need for irrigation, and this decreases the radiological dose. A drastic climatic change, such as an increase in temperature from 10 to 20 degrees C and decrease in precipitation from 0.3 to 0.2 m during the growing season, is estimated to increase the dose by a factor of four. This is a relatively small change compared to the range of doses that arise from the variability and uncertainty in many of the parameters used in the environmental assessment models. Therefore, it is likely that the results of probabilistic dose assessment models can include the consequences of short-term climatic change. 39 refs., 3 figs

  13. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Complementary considerations 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    Complementary Considerations sits within Posiva Oy's Safety Case 'TURVA-2012' report portfolio and has the objective of enhancing confidence in the outcomes of the safety assessment for a spent nuclear fuel repository to be constructed at Olkiluoto, Finland. The main emphasis in this report is on the evidence and understanding that can be gained from observations at the site, including its regional geological environment, and from natural and anthropogenic analogues for the repository, its components and the processes that affect safety. In particular, the report addresses diverse and less quantifiable types of evidence and arguments that are enclosed to enhance confidence in the outcome of the safety assessment. These complementary considerations have been described as evaluations, evidence and qualitative supporting arguments that lie outside the scope of the other reports of the quantitative safety assessment. The experience with natural analogues for the long-term durability of the materials involved and the extent of processes provides high confidence in our understanding of the disposal system and its evolution. For each engineered barrier and key process, there is increasing analogue evidence to support the conceptual models and parameters. Regarding the suitability of the Olkiluoto site to host a spent fuel repository, a number of factors have been identified that indicate the suitability of crystalline host rock in general, and that of the Olkiluoto site in particular. The report also provides radiation background information for the use of complementary indicators, which aid in putting the results of the safety analysis presented in Assessment of Radionuclide Release Scenarios for the Repository System and Biosphere Assessment in a broader perspective to show that the radiation originating from a spent nuclear fuel repository remains in most cases much below natural background radiation or that caused by non-nuclear industries. (orig.)

  14. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Complementary considerations 2012

    International Nuclear Information System (INIS)

    2012-12-01

    Complementary Considerations sits within Posiva Oy's Safety Case 'TURVA-2012' report portfolio and has the objective of enhancing confidence in the outcomes of the safety assessment for a spent nuclear fuel repository to be constructed at Olkiluoto, Finland. The main emphasis in this report is on the evidence and understanding that can be gained from observations at the site, including its regional geological environment, and from natural and anthropogenic analogues for the repository, its components and the processes that affect safety. In particular, the report addresses diverse and less quantifiable types of evidence and arguments that are enclosed to enhance confidence in the outcome of the safety assessment. These complementary considerations have been described as evaluations, evidence and qualitative supporting arguments that lie outside the scope of the other reports of the quantitative safety assessment. The experience with natural analogues for the long-term durability of the materials involved and the extent of processes provides high confidence in our understanding of the disposal system and its evolution. For each engineered barrier and key process, there is increasing analogue evidence to support the conceptual models and parameters. Regarding the suitability of the Olkiluoto site to host a spent fuel repository, a number of factors have been identified that indicate the suitability of crystalline host rock in general, and that of the Olkiluoto site in particular. The report also provides radiation background information for the use of complementary indicators, which aid in putting the results of the safety analysis presented in Assessment of Radionuclide Release Scenarios for the Repository System and Biosphere Assessment in a broader perspective to show that the radiation originating from a spent nuclear fuel repository remains in most cases much below natural background radiation or that caused by non-nuclear industries. (orig.)

  15. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Complementary considerations 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    Complementary Considerations sits within Posiva Oy's Safety Case 'TURVA-2012' report portfolio and has the objective of enhancing confidence in the outcomes of the safety assessment for a spent nuclear fuel repository to be constructed at Olkiluoto, Finland. The main emphasis in this report is on the evidence and understanding that can be gained from observations at the site, including its regional geological environment, and from natural and anthropogenic analogues for the repository, its components and the processes that affect safety. In particular, the report addresses diverse and less quantifiable types of evidence and arguments that are enclosed to enhance confidence in the outcome of the safety assessment. These complementary considerations have been described as evaluations, evidence and qualitative supporting arguments that lie outside the scope of the other reports of the quantitative safety assessment. The experience with natural analogues for the long-term durability of the materials involved and the extent of processes provides high confidence in our understanding of the disposal system and its evolution. For each engineered barrier and key process, there is increasing analogue evidence to support the conceptual models and parameters. Regarding the suitability of the Olkiluoto site to host a spent fuel repository, a number of factors have been identified that indicate the suitability of crystalline host rock in general, and that of the Olkiluoto site in particular. The report also provides radiation background information for the use of complementary indicators, which aid in putting the results of the safety analysis presented in Assessment of Radionuclide Release Scenarios for the Repository System and Biosphere Assessment in a broader perspective to show that the radiation originating from a spent nuclear fuel repository remains in most cases much below natural background radiation or that caused by non-nuclear industries. (orig.)

  16. DUSCOBS - a depleted-uranium silicate backfill for transport, storage, and disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Pope, R.B.; Ashline, R.C.; DeHart, M.D.; Childs, K.W.; Tang, J.S.

    1995-01-01

    A Depleted Uranium Silicate COntainer Backfill System (DUSCOBS) is proposed that would use small, isotopically-depleted uranium silicate glass beads as a backfill material inside storage, transport, and repository waste packages containing spent nuclear fuel (SNF). The uranium silicate glass beads would fill all void space inside the package including the coolant channels inside SNF assemblies. Based on preliminary analysis, the following benefits have been identified. DUSCOBS improves repository waste package performance by three mechanisms. First, it reduces the radionuclide releases from SNF when water enters the waste package by creating a local uranium silicate saturated groundwater environment that suppresses (1) the dissolution and/or transformation of uranium dioxide fuel pellets and, hence, (2) the release of radionuclides incorporated into the SNF pellets. Second, the potential for long-term nuclear criticality is reduced by isotopic exchange of enriched uranium in SNF with the depleted uranium (DU) in the glass. Third, the backfill reduces radiation interactions between SNF and the local environment (package and local geology) and thus reduces generation of hydrogen, acids, and other chemicals that degrade the waste package system. In addition, the DUSCOBS improves the integrity of the package by acting as a packing material and ensures criticality control for the package during SNF storage and transport. Finally, DUSCOBS provides a potential method to dispose of significant quantities of excess DU from uranium enrichment plants at potential economic savings. DUSCOBS is a new concept. Consequently, the concept has not been optimized or demonstrated in laboratory experiments

  17. The preservation of a cadaver by a clay sealant: Implications for the disposal of nuclear fuel waste

    International Nuclear Information System (INIS)

    Lee, C.F.; Oscarson, D.W.; Cheung, S.C.H.

    1986-01-01

    This report documents a case history in which a cadaver and the associated burial objects were found well preserved after being buried for more than 2100 years in Southern China. The preservation is attributed to a layer of kaolin that surrounded the coffin and served as a barrier to water and air movement. The implications for the disposal of nuclear fuel waste are discussed

  18. Tests for manufacturing technology of disposal canisters for nuclear spent fuel

    International Nuclear Information System (INIS)

    Raiko, H.; Salonen, T.; Meuronen, I.; Lehto, K.

    1999-06-01

    The summary and status of the results of the manufacturing technology programmes concerning the disposal canister for spent nuclear fuel conducted by Posiva Oy are given in this report. Posiva has maintained a draft plan for a disposal canister design and an assessment of potential manufacturing technologies for about ten years in Finland. Now, during the year 1999, the first full scale demonstration canister is manufactured in Finland. The technology used for manufacturing of this prototype is developed by Posiva Oy mainly in co-operation with domestic industry. The main partner in developing the manufacturing technology for the copper shell has been Outokumpu Poricopper Oy, Pori, Finland, and the main partner in developing the technology for the iron insert of the canister has been Valmet Oyj Rautpohja Foundry, Jyvaeskylae, Finland. In both areas many subcontractors have been used, predominantly domestic engineering workshops, but also some foreign subcontractors, e.g. for EB-welding, who have had large enough welding equipment. This report describes the developing programmes for canister manufacturing, evaluates the results and presents some alternative methods, and tries to evaluate the pros and contras of them. In addition, the adequacy of the achieved technological know-how is assessed in respect of the required quality of the disposal canister. The following manufacturing technologies have been the concrete topics of the development programme: Electron beam welding technology development for thick-walled copper, Casting of massive copper billets, Hot rolling of thick-walled copper plates, Hot pressing and forging in lid manufacture, Extrusion and drawing of copper tubes, Bending of copper plates by roller or press, Machining of copper, Residual stress removal by heat treatment, Non-destructive testing, Long-term strength of EB-welds, Casting and machining of the iron insert of the canister The specialists from all the main developing partner companies have

  19. Microbially influenced corrosion of copper nuclear fuel waste containers in a Canadian disposal vault

    Energy Technology Data Exchange (ETDEWEB)

    King, F

    1996-11-01

    An assessment of the potential for microbially influenced corrosion (MIC) of copper nuclear fuel waste containers in a Canadian disposal vault is presented. The assessment is based on a consideration of the microbial activity within a disposal vault, the reported cases of MIC of Cu alloys in the literature and the known corrosion behaviour of Cu. Because of the critical role of biofilms in the reported cases of MIC, their formation and properties are discussed in detail. Next, the literature on the MIC of Cu alloys is briefly reviewed. The various MIC mechanisms proposed are critically discussed and the implications for the corrosion of Cu containers considered. In the majority of literature cases, MIC depends on alternating aerated and deaerated environments, with accelerated corrosion being observed when fresh aerated water replaces stagnant water, e.g., the MIC of Cu-Ni heat exchangers in polluted seawater and the microbially influenced pitting of Cu water pipes. Finally, because of the predominance of corrosion by sulphate-reducing bacteria (SRB) in the MIC literature, the abiotic behaviour of Cu alloys in sulphide solutions is also reviewed. The effect of the evolving environment in a disposal vault on the extent and location of microbial activity is discussed. Biofilm formation on the container surface is considered unlikely throughout the container lifetime, but especially initially when the environmental conditions will be particularly aggressive. Microbial activity in areas of the vault away from the container is possible, however. Corrosion of the container could then occur if microbial metabolic by-products diffuse to the container surface. Sulphide, produced by the action of SRB are considered to be the most likely cause of container corrosion. It is concluded that the only likely form of MIC of Cu containers will result from sulphide produced by SRB diffusing to the container surface. A modelling procedure for predicting the extent of corrosion is

  20. The disposal of Canada's nuclear fuel waste: the geosphere model for postclosure assessment

    International Nuclear Information System (INIS)

    Davison, C.C.; Chan, T.; Brown, A.

    1994-01-01

    AECL is preparing an Environmental Impact Statement (EIS) of a concept for disposing of Canada's nuclear fuel waste. The disposal concept is that of a sealed vault constructed at a depth of 500 to 1 000 m in plutonic rock of the Canadian Shield. This report is one of nine primary references for the EIS. A probabilistic system variability analysis code (SYVAC3) has been used to perform a case study assessment of the long-term safety and environmental impacts for the EIS. This report describes the methodology for developing the SYVAC3-CC3 Geosphere Model (GEONET) which simulates the transport of contaminants from the vault through the geosphere to the biosphere. It also discusses the data used to construct the model, as well as assumptions and justifications for the data and model. The geosphere consists of the rock mass surrounding the vault, including the groundwater in the pores and cracks in the rock, the materials used to seal the shafts and exploratory boreholes at the site, and a domestic water well that is assumed to intersect the pathway of most rapid transport from the vault to the biosphere. GEONET simulates the movement of groundwater from the vault through the geosphere to discharge locations at the biosphere; the movement of contaminants in the groundwater by advection, hydrodynamic dispersion, and molecular diffusion; chemical sorption of contaminants onto minerals in the rock during transport; radioactive decay; and the rate of discharge of vault contaminants to the biosphere. Development of the Geosphere Model involves several steps. The initial step is to construct a conceptual model of the subsurface geological structure and ground water flow conditions using data from site investigations and laboratory tests. Once a conceptual model has been constructed, the coupled equations describing 3-D groundwater flow and heat transport are solved using the MOTIF finite-element code to calculate hydraulic head and groundwater velocity distributions. Next

  1. Analysis of economic impacts on waste management and disposal in different nuclear fuel cycles

    International Nuclear Information System (INIS)

    1979-09-01

    The costs for waste management and disposal have been estimated for the comparison of the seven reference fuel cycles selected by INFCE working group 7, covering the waste management of all steps in each fuel cycle: mining and milling, conversion and enrichment, fuel fabrication, reactor operation, reprocessing or spent fuel packaging, and disposal in a geologic formation (salt or hard rock). Values for a large variety of parameters had to be assumed. The cost figures as broken down in detail in the report have been calculated for an electricity production of 50 Gigawatt-years per year. The sum totals amount to about 8 to 17 million US (as of January 1, 1978) per Gigawattyear electricity produced, depending on the fuel cycle and on the geologic host formation of the repository. No savings should be obtained for a larger capacity, but a capacity of 10 Gigawatt would entail figures 10 to 25% higher. This result has to be seen under the perspective of the sometimes conservative and arbitrary assumptions of WG 7 with respect to waste arisings and their disposal. Furthermore, as compared to the revenues for the electricity sold, the relative difference between the reference fuel cycles in costs of waste management and disposal does not appear to be significant, as they range only from 1 to 2% of the total electricity costs

  2. Disposal of spent fuel

    International Nuclear Information System (INIS)

    Blomeke, J.O.; Ferguson, D.E.; Croff, A.G.

    1978-01-01

    Based on preliminary analyses, spent fuel assemblies are an acceptable form for waste disposal. The following studies appear necessary to bring our knowledge of spent fuel as a final disposal form to a level comparable with that of the solidified wastes from reprocessing: 1. A complete systems analysis is needed of spent fuel disposition from reactor discharge to final isolation in a repository. 2. Since it appears desirable to encase the spent fuel assembly in a metal canister, candidate materials for this container need to be studied. 3. It is highly likely that some ''filler'' material will be needed between the fuel elements and the can. 4. Leachability, stability, and waste-rock interaction studies should be carried out on the fuels. The major disadvantages of spent fuel as a disposal form are the lower maximum heat loading, 60 kW/acre versus 150 kW/acre for high-level waste from a reprocessing plant; the greater long-term potential hazard due to the larger quantities of plutonium and uranium introduced into a repository; and the possibility of criticality in case the repository is breached. The major advantages are the lower cost and increased near-term safety resulting from eliminating reprocessing and the treatment and handling of the wastes therefrom

  3. The surface water model for assessing Canada's nuclear fuel waste disposal concept

    International Nuclear Information System (INIS)

    Bird, G.A.; Stephenson, M.; Cornett, R.J.

    1993-01-01

    Canada's Nuclear Fuel Waste Management Program (NFWMP) is investigating the concept of disposal of nuclear fuel waste in a vault excavated deep in crystalline rock on the Canadian Shield. Probabilistic vault, geosphere, and biosphere models are implemented using Monte Carlo simulation techniques to trace nuclides transported in groundwater to the surface environment and humans far into the future. This paper describes the surface water submodel and its parameter values, sensitivity analysis, and validation. The surface water model is a simple, time-dependent, mass balance model of a lake that calculates radioactive and stable isotope contaminant concentrations in lake water and sediment. These concentrations are input to the other submodels and used to predict the radiological dose to humans and other biota. Parameter values in the model are based on the literature and the author's own data, and are generic to Canadian Shield lakes. Most parameters are represented by log normally distributed probability density functions. Sensitivity analysis indicates that nuclide concentrations in lake water and sediment are governed primarily by hydrological flushing with catchment area being the most important parameter. When catchment area is held constant lake area and nuclide transfer rate from water to sediment strongly influence concentrations in both water and sediment. For volatile nuclides, gaseous evasion also has a marked influence on concentrations in both water and sediment, whereas sedimentation rate strongly influences sediment nuclide concentrations. Validation tests demonstrate that the models predictions for 60 Co, 134 Cs, 3 H, P, Cd and Ca are consistent with empirical data when uncertainties are taken into account

  4. Nuclear fuels

    International Nuclear Information System (INIS)

    Beauvy, M.; Berthoud, G.; Defranceschi, M.; Ducros, G.; Guerin, Y.; Limoge, Y.; Madic, Ch.; Santarini, G.; Seiler, J.M.; Sollogoub, P.; Vernaz, E.; Guillet, J.L.; Ballagny, A.; Bechade, J.L.; Bonin, B.; Brachet, J.Ch.; Delpech, M.; Dubois, S.; Ferry, C.; Freyss, M.; Gilbon, D.; Grouiller, J.P.; Iracane, D.; Lansiart, S.; Lemoine, P.; Lenain, R.; Marsault, Ph.; Michel, B.; Noirot, J.; Parrat, D.; Pelletier, M.; Perrais, Ch.; Phelip, M.; Pillon, S.; Poinssot, Ch.; Vallory, J.; Valot, C.; Pradel, Ph.; Bonin, B.; Bouquin, B.; Dozol, M.; Lecomte, M.; Vallee, A.; Bazile, F.; Parisot, J.F.; Finot, P.; Roberts, J.F.

    2009-01-01

    Fuel is one of the essential components in a reactor. It is within that fuel that nuclear reactions take place, i.e. fission of heavy atoms, uranium and plutonium. Fuel is at the core of the reactor, but equally at the core of the nuclear system as a whole. Fuel design and properties influence reactor behavior, performance, and safety. Even though it only accounts for a small part of the cost per kilowatt-hour of power provided by current nuclear power plants, good utilization of fuel is a major economic issue. Major advances have yet to be achieved, to ensure longer in-reactor dwell-time, thus enabling fuel to yield more energy; and improve ruggedness. Aside from economics, and safety, such strategic issues as use of plutonium, conservation of resources, and nuclear waste management have to be addressed, and true technological challenges arise. This Monograph surveys current knowledge regarding in-reactor behavior, operating limits, and avenues for R and D. It also provides illustrations of ongoing research work, setting out a few noteworthy results recently achieved. Content: 1 - Introduction; 2 - Water reactor fuel: What are the features of water reactor fuel? 9 (What is the purpose of a nuclear fuel?, Ceramic fuel, Fuel rods, PWR fuel assemblies, BWR fuel assemblies); Fabrication of water reactor fuels (Fabrication of UO 2 pellets, Fabrication of MOX (mixed uranium-plutonium oxide) pellets, Fabrication of claddings); In-reactor behavior of UO 2 and MOX fuels (Irradiation conditions during nominal operation, Heat generation, and removal, The processes involved at the start of irradiation, Fission gas behavior, Microstructural changes); Water reactor fuel behavior in loss of tightness conditions (Cladding, the first containment barrier, Causes of failure, Consequences of a failure); Microscopic morphology of fuel ceramic and its evolution under irradiation; Migration and localization of fission products in UOX and MOX matrices (The ceramic under irradiation

  5. Nuclear fuels

    Energy Technology Data Exchange (ETDEWEB)

    Beauvy, M.; Berthoud, G.; Defranceschi, M.; Ducros, G.; Guerin, Y.; Limoge, Y.; Madic, Ch.; Santarini, G.; Seiler, J.M.; Sollogoub, P.; Vernaz, E.; Guillet, J.L.; Ballagny, A.; Bechade, J.L.; Bonin, B.; Brachet, J.Ch.; Delpech, M.; Dubois, S.; Ferry, C.; Freyss, M.; Gilbon, D.; Grouiller, J.P.; Iracane, D.; Lansiart, S.; Lemoine, P.; Lenain, R.; Marsault, Ph.; Michel, B.; Noirot, J.; Parrat, D.; Pelletier, M.; Perrais, Ch.; Phelip, M.; Pillon, S.; Poinssot, Ch.; Vallory, J.; Valot, C.; Pradel, Ph.; Bonin, B.; Bouquin, B.; Dozol, M.; Lecomte, M.; Vallee, A.; Bazile, F.; Parisot, J.F.; Finot, P.; Roberts, J.F

    2009-07-01

    nature of spent nuclear fuel, Anticipated evolution of fuel in dry storage, Anticipated evolution of fuel in deep geological disposal); Boiling-water reactor fuel (Similarities, and differences with PWR fuel, Axial and radial zoning, Rod and channel box sizes, Poisoning and reactivity control, Cladding specific characteristics, Trends in fuel evolution); 3 - Liquid-metal-cooled fast reactor fuel: Fast-neutron irradiation damage in structural materials (Fast-neutron-induced damage in metals, What materials should be used?); Fuels and targets for fast-reactor transmutation (Fast reactors: reactors affording the ability to carry out effective actinide transmutation, Recycling: homogeneous, or heterogeneous?); 4 - gas-cooled reactor fuel: Particle fuel (From the initial concept to the advanced TRISO particle concept, Kernel fabrication processes, Particle coating by chemical vapor deposition, Fuel element fabrication: particle compaction, Characterization of fuel particles, and elements, From HTR fuel to VHTR and GFR fuels: the GAIA facility at CEA/Cadarache); Irradiation behavior of particle fuels (Particle fuel: a variety of failure modes for a high-strength object, The amoeba effect, Fission product behavior, and diffusion in particle fuels); Mechanical modeling of particle fuel; Very-high-temperature reactor (VHTR) fuel; Gas-cooled fast reactor (GFR) fuel (The specifications for GFR fuel, GFR fissile material, First containment baffler materials, GFR fuel element concepts); 5 - Research reactor fuels (A considerable feedback from experience, Conversion of French reactors to low-enriched ({<=}20% U-235)U{sub 3}Si{sub 2} fuel, Conversion of all reactors: R and D requirements for high-performance reactors, An 'advanced' research reactor fuel: UMo, The startup fuel for the Jules Horowitz Reactor (JHR) will still be U{sub 3}Si{sub 2}-Al; 6 - An instrument for future fuel research: the Jules Horowitz Reactor (JHR): Fuel irradiation experiments in JHR, JHR: a flexible

  6. Disposal of spent fuel from German nuclear power plants - paper work or technology?

    International Nuclear Information System (INIS)

    Graf, R.; Filbert, W.

    2006-01-01

    The reference concept 'direct disposal of spent fuel' was developed as an alternative to spent fuel reprocessing and vitrified HLW disposal. The technical facilities necessary for the implementation of this reference concept - the so called POLLUX-concept, e.g. interim storages for casks containing spent fuel, a pilot conditioning facility, and a special cask 'POLLUX' for final disposal have been built. With view to a geological salt formation all handling procedures for the repository were tested aboveground in a test facility at a 1:1 scale. To optimise the concept all operational steps are reviewed for possible improvement. Most promising are a concept using canisters (BSK 3) instead of POLLUX casks, and the direct disposal of transport and storage casks (DIREGT-concept) which is the most recent one and has been designed for the direct disposal of large transport and storage casks. The final exploration of the pre-selected repository site is still pending, from the industries point of view due to political reasons only. The present paper describes the main concepts and their status as of today. (author)

  7. Comparative evaluation of coating techniques for the corrosion protection of disposal container for spent nuclear fuel

    International Nuclear Information System (INIS)

    Chun, Kwan Sik; Kim, Sung Soo; Park, Chong Mook; Choi, Jong Won

    2005-02-01

    To propose a suitable coating technique to prevent corrosion on metal or metal alloys of a waste container to be used for the disposal of spent nuclear fuel, several methods related to spray coating and vapor deposition techniques have been comparatively evaluated, based on some major factors recommended. From these comparative results, it can be suggested that the best coating methods among the existing techniques in Korea would be HVOF and low pressure plasma spray. Even though the surface of the container coated by these methods would be coated, pores could be remained in the coated film. And therefore post-treatment methods for eliminating the pores have been briefly introduced to keep the life time of the container. The other techniques, the cold spray and hollow cathode discharge, may become excellent coating methods in the future if they are extensively researched to apply for coating on the container. An optimal process among the recommended methods should be selected by considering the state of container, such as an empty or a loaded container, and also related coating materials. For the support to this, the characteristics of the coating materials and the coated films and the durability of this film under a repository condition should be analyzed in detail

  8. Final disposal of spent nuclear fuel-equipment for site characterization

    International Nuclear Information System (INIS)

    Almen, K.; Hansson, K.; Johansson, B.E.; Nilsson, G.; Andersson, O.; Wikberg, P.; Aahagen, H.

    1983-05-01

    The suitability of a certain geological formation as a repository for the final disposal of spent nuclear fuel can be determined only after detailed investigation and analysis. The purpose of the investigations is to provide information on the geology and the hydrology and chemistry of the site concerned. The value of these data largely depends on the way in which they have been collected. The report of the findings should enable the investigating party to evaluate the function and the accuracy of the equipment with which field data have been collected for KBS 3. This report describes the geophysical equipment, the hydraulic testing equipment, the water chemistry sample extracting equipment and the core-logging equipment used. The objectives of the instrument development have been: - to obtain a high data quality. - to collect data automatically in logs and tape recorders for direct transfer to a central processing unit. - to provide back-up in order to counteract loss of data. - to make instrument more efficient. (author)

  9. Predicting the effects of microbial activity on the corrosion of copper nuclear fuel waste disposal containers

    International Nuclear Information System (INIS)

    King, F.; Stroes-Gascoyne, S.

    1996-08-01

    Microbially influenced corrosion (MIC) of copper nuclear fuel waste containers may occur in a disposal vault located 500-1000 m underground in the granitic rock of the Canadian Shield. The extent and diversity of microbial activity in the vault is expected to be limited initially because of the aggressive conditions produced by γ-radiation, elevated temperatures and desiccation of the clay-based buffer in which the containers will be embedded. Experimental results on the heat- and radiation-sensitivity of the natural microbiota in buffer material are presented. The data suggest that the low water activity in the buffer material will severely limit the growth of microbes near the container. The most likely form of MIC involves sulphate-reducing bacteria (SRB). Electrochemical experiments using a clay-covered copper electrode have shown that sulphide ions produced by SRB could diffuse through buffer material and induce corrosion of the container. A method to predict the long-term corrosion behaviour is presented. (author)

  10. A simple analysis of potential radiological exposure from geological disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    Amiro, B.D.; Dormuth, K.W.

    1996-02-01

    AECL has submitted an environmental impact statement (EIS) describing its proposal for geological disposal of Canada's nuclear fuel waste. The EIS presents a detailed analysis of potential radiation exposure of an individual of a critical group of people in a hypothetical case. In this report, we provide a simpler analysis of potential exposure in the hope that the inherent safety of the disposal will be more readily evident from the analysis. A key to the simplification is the elimination from the analysis of the complex transport processes through disposal vault sealing materials and the geosphere. We also eliminate the relatively complex function describing the failure of the thin-walled titanium containers in the case study presented in the EIS. We therefore conceptually replace the thin-walled titanium containers with thicker-walled copper containers, are expected to remain intact much longer than 10,000 a, the period for which a quantitative estimate of individual exposure is made. However, about 1 in 5000 containers could have small defects that were undetected during manufacture. Our analysis applies only to the case of an undisrupted vault. We assume that the vault and geosphere barriers remain intact and prevent immobile radionuclides from reaching the biosphere. However, we also assume that the three most important mobile radionuclides can escape through an undected manufacturing defect in the container wall, and that the flux of these radionuclides is diluted by well water being used by people. We have focused on 129 I, 36 Cl and 14 C, because these nuclides are found to be the dominant source of exposure in more complex analyses. If a single container released radionuclides to well water, we estimate dose rates of about 1 μSv.a -1 from drinking water and 29 μSv.a -1 , which the Atomic Eenrgy Control Board has adopted as a de minimis dose rate, i.e., a dose rate so small as to not warrant institutional control. We believe that the dose rates are

  11. Microbially influenced corrosion of copper nuclear fuel waste containers in a Canadian disposal vault

    International Nuclear Information System (INIS)

    King, F.

    1996-11-01

    An assessment of the potential for microbially influenced corrosion (MIC) of copper nuclear fuel waste containers in a Canadian disposal vault is presented. The assessment is based on a consideration of the microbial activity within a disposal vault, the reported cases of MIC of Cu alloys in the literature and the known corrosion behaviour of Cu. Because of the critical role of biofilms in the reported cases of MIC, their formation and properties are discussed in detail. Next, the literature on the MIC of Cu alloys is briefly reviewed. The various MIC mechanisms proposed are critically discussed and the implications for the corrosion of Cu containers considered. In the majority of literature cases, MIC depends on alternating aerated and deaerated environments, with accelerated corrosion being observed when fresh aerated water replaces stagnant water, e.g., the MIC of Cu-Ni heat exchangers in polluted seawater and the microbially influenced pitting of Cu water pipes. Finally, because of the predominance of corrosion by sulphate-reducing bacteria (SRB) in the MIC literature, the abiotic behaviour of Cu alloys in sulphide solutions is also reviewed. The effect of the evolving environment in a disposal vault on the extent and location of microbial activity is discussed. Biofilm formation on the container surface is considered unlikely throughout the container lifetime, but especially initially when the environmental conditions will be particularly aggressive. Microbial activity in areas of the vault away from the container is possible, however. Corrosion of the container could then occur if microbial metabolic by-products diffuse to the container surface. Sulphide, produced by the action of SRB are considered to be the most likely cause of container corrosion. It is concluded that the only likely form of MIC of Cu containers will result from sulphide produced by SRB diffusing to the container surface. A modelling procedure for predicting the extent of corrosion is

  12. Final disposal of spent nuclear fuel in Finnish bedrock - Kivetty site report

    International Nuclear Information System (INIS)

    Anttila, P.; Ahokas, H.; Front, K.

    1999-06-01

    Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Haestholmen in Loviisa, Kivetty in Aeaenekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Kivetty. The bedrock of Kivetty belongs to the large Svecofennian granitoid complex of central Finland, about 1880 million years in age. The most common rock type is porphyritic granodiorite, which is cut by younger medium-grained granodiorite and porphyritic or even-grained granite. Minor bodies of gabbro, older than the porphyritic granodiorite, are also present. The granitoids show evidence of two deformation phases. Altogether 29 bedrock 'structures' (R-structures) have been modelled at the investigation site, most of them representing steeply dipping fracture zones. The rock mass between the fracture zones represents what is termed 'intact rock', which is typically hard, unweathered and sparsely fractured. The R-structures are generally hydraulically more conductive than the intact rock and their mean transmissivity is 1.3-10 -6 m 2 /s. The corresponding mean of the hydraulic conductivity values for the intact rock, measured using a 2 m packer interval is 4*10 -11 m 2 /s, if a lognormal distribution for all measured values is assumed. A clear decrease in hydraulic conductivity with depth has been found for the intact rock, and there seems to be a parallel decrease in the transmissivity of structures. In addition, the hydraulically conductive fractures seem to be more frequent and their transmissivities higher in the uppermost 100 - 200 m of the bedrock than at greater depths. The groundwater of Kivetty is classified as fresh water and

  13. Final disposal of spent nuclear fuel in Finnish bedrock - Romuvaara site report

    International Nuclear Information System (INIS)

    Anttila, P.; Ahokas, H.; Front, K.

    1999-06-01

    Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Haestholmen in Loviisa, Kivetty in Aeaenekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Romuvaara. The bedrock of Romuvaara belongs to the Archean basement complex, whose oldest parts date back over 2800 million years. The bedrock consists mainly of migmatitic banded gneisses (tonalite, leucotonalite and mica gneiss), which are cut by granodiorite and metadiabase dykes. The rocks, excluding the metadiabase, have undergone a polyphase Archaean deformation. Altogether 31 bedrock structures (R-structures) have been modelled at the investigation site, most of them representing steeply dipping fracture zones. The rock mass between the fracture zones represents what is termed 'intact rock', which is typically hard, unweathered and sparsely fractured. The R-structures are generally hydraulically more conductive than the intact rock and their mean transmissivity is 1.6 x 10 -7 m 2 /s. The corresponding mean of the hydraulic conductivity values for the intact rock measured using a 2 m packer interval is 8 x 10 -12 m/s, if a lognormal distribution for all measured values is assumed. A clear decrease in hydraulic conductivity with depth has been found, for both the R-structures and the intact rock. In addition, the hydraulically conductive fractures seem to be more frequent and their transmissivities higher in the uppermost 100 - 200 m of the bedrock than at greater depths. The groundwater of Romuvaara is classified as fresh water and the Total Dissolved Solids (TDS) and chloride contents increase with depth. The chemically most evolved

  14. Final disposal of spent nuclear fuel in Finnish bedrock - Romuvaara site report

    Energy Technology Data Exchange (ETDEWEB)

    Anttila, P. [Fortum Engineering Oy (Finland); Ahokas, H. [Fintact Oy (Finland); Front, K. [VTT Communities and Infrastructure, Espoo (Finland)] [and others

    1999-06-01

    Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Haestholmen in Loviisa, Kivetty in Aeaenekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Romuvaara. The bedrock of Romuvaara belongs to the Archean basement complex, whose oldest parts date back over 2800 million years. The bedrock consists mainly of migmatitic banded gneisses (tonalite, leucotonalite and mica gneiss), which are cut by granodiorite and metadiabase dykes. The rocks, excluding the metadiabase, have undergone a polyphase Archaean deformation. Altogether 31 bedrock structures (R-structures) have been modelled at the investigation site, most of them representing steeply dipping fracture zones. The rock mass between the fracture zones represents what is termed `intact rock`, which is typically hard, unweathered and sparsely fractured. The R-structures are generally hydraulically more conductive than the intact rock and their mean transmissivity is 1.6 x 10{sup -7} m{sup 2}/s. The corresponding mean of the hydraulic conductivity values for the intact rock measured using a 2 m packer interval is 8 x 10{sup -12} m/s, if a lognormal distribution for all measured values is assumed. A clear decrease in hydraulic conductivity with depth has been found, for both the R-structures and the intact rock. In addition, the hydraulically conductive fractures seem to be more frequent and their transmissivities higher in the uppermost 100 - 200 m of the bedrock than at greater depths. The groundwater of Romuvaara is classified as fresh water and the Total Dissolved Solids (TDS) and chloride contents increase with depth. The chemically

  15. The use of borehole geophysical logs and hydrologic tests to characterize plutonic rock for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Davison, C.C.

    1984-05-01

    The selection of an igneous rock body for the disposal of nuclear fuel waste will likely require the drilling and testing of a number of deep investigative boreholes in the rock body. Although coring of at least one hole at each Research Area will be essential, methods for making in situ geophysical and hydrological measurements can substitute for widespread coring and result in significant savings in time and money. A number of borehole methods have been applied to the investigation of plutonic rocks at Whiteshell Nuclear Research Establishment and Chalk River Nuclear Laboratories in Canada

  16. Overview of the US program for developing a waste disposal system for spent nuclear fuel and high-level waste

    International Nuclear Information System (INIS)

    Kay, C.E.

    1988-01-01

    Safe disposal of spent nuclear fuel and radioactive high-level waste (HLW) has been a matter of national concern ever since the first US civilian nuclear reactor began generating electricity in 1957. Based on current projections of commercial generating capacity, by the turn of the century, there will be >40,000 tonne of spent fuel in the Untied States. In addition to commercial spent fuel, defense HLW is generated in the United States and currently stored at three US Department of Energy (DOE) sites: The Nuclear Waste Policy Amendments Act of 1987 provided for financial incentives to host a repository or a monitored retrievable storage (MRS) facility; mandated the areas in which DOE's siting efforts should concentrate (Yucca Mountain, Nevada); required termination of site-specific activities at other sites; required a resisting process for an MRS facility, which DOE had proposed as an integral part of the waste disposal system; terminated all activities for identifying candidates for a second repository; established an 11-member Nuclear Waste Technical Review Board; established a three-member MRS commission to be appointed by heads of the US Senate and House; directed the President to appoint a negotiator to seek a state or Indian tribe willing to host a repository or MRS facility at a suitable site and to negotiate terms and conditions under which the state or tribe would be willing to host such a facility; and amended, adjusted, or established other requirements contained in the 1982 law

  17. Identification of contaminants of concern for the postclosure assessment of the concept for the disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    Goodwin, B.W.; Mehta, K.K.

    1994-03-01

    The concept for the disposal of Canada's nuclear fuel waste involves the isolation of irradiated fuel in corrosion-resistant containers emplaced din din a vault located deep in crystalline rock of the Canadian Shield. To estimate potential impacts on members of a critical group far into the future, a postclosure assessment evaluates the long-term safety of the concept. Although the nuclear fuel waste from CANDU (Canada Deuterium Uranium) power generating stations contains several hundreds of potentially toxic radionuclides and chemical elements (referred to as contaminants), many of these would not lead to significant impacts. This report provides an upper bound on estimated radiation dose and chemical toxicity effects on humans from all potentially toxic contaminants, and it identifies those that require detailed consideration in the postclosure assessment. This report also examines the origins and properties of the contaminants. Properties of interest include radioactive half-life, inventory, mobility in groundwaters and sorption on rock, degree of toxicity, and precursors and progeny (or parents and daughters) for members of a decay chain. The report considers how these properties affect the behaviour of different contaminants in different parts of the disposal system. The discussion leads to suggested methods of treatment of different contaminants when simulating their fate within the disposal system. In particular, recommendations are made on how the actinide decay chains can be simplified for study in the postclosure assessment. (author). 56 refs., 22 tabs., 12 figs

  18. Perceived risks of nuclear fuel waste disposal: trust, compensation, and public acceptance in Canada

    International Nuclear Information System (INIS)

    Hine, D.W.; Summers, C.

    1996-01-01

    AECL's recommendation to place the high-level radioactive waste in corrosion resistant containers and bury it in underground vaults several hundred metres deep in the rock of the Canadian shield is presently under federal review. If and when the disposal concept is approved by the federal review panel, a search will begin for a suitable host community. Given that siting guidelines prevent the government from unilaterally imposing the waste on a reluctant community, identifying a suitable site may represent the single greatest obstacle to successfully implementing the disposal concept. Even if the concept is approved by the review panel, it may be very difficult to find a community that is willing to accept the waste. In the US, efforts to site an underground disposal facility for high-level nuclear waste at Yucca Mountain has run into strong opposition from local residents and politicians, resulting in long delays and major cost overruns

  19. Report on financing the disposal of commercial spent nuclear fuel and processed high-level radioactive waste

    International Nuclear Information System (INIS)

    Benny, R.I.; Sprecher, W.M.

    1983-06-01

    Projected revenues generated from the 1.0 mill per kWh fee mandated by the Act are sufficient to cover the full range of reference case program costs, assuming 3% annual inflation and nuclear installed capacity of 165 gigawatts-electric by the year 2000. Total estimated costs of the reference waste disposal program, encompassing either spent nuclear fuel disposal or reprocessing waste disposal, range between $18 to 20 billion in constant 1982 dollars. Sensitivity case analyses established upper and lower program cost bounds of $28 billion and $16 billion, respectively (in 1982 dollars). In terms of discounted levelized unit costs, the disposal of spent fuel equates to $122 to 125 per kilogram (uranium) compared with $115 to 119 per kilogram for the reprocessing waste equivalent. The levelized unit costs for reprocessing exclude the solidification of liquid wastes. Such costs are estimated to be $8 per kilogram. Discounted levelized unit costs corresponding to the upper and lower limits of the sensitivity cases equate to $176 per kilogram and $107 per kilogram. The 1.0 mill per kWh fee will be reviewed annually and adjusted, if necessary, to accommodate changes in program costs due to inflation and program shifts. When adjustments are made for applicable discount rates, inflation, repository design changes, and other factors, levelized unit costs for the reference case presented in this analysis agree closely with the results of two previous Department of Energy studies concerning charges for spent fuel storage and disposal services provided by the Federal government. The cost estimates developed for the program were based on the best available data

  20. The future supply of and demand for candidate materials for the fabrication of nuclear fuel waste disposal containers

    International Nuclear Information System (INIS)

    Grover, L.K.

    1990-01-01

    This report summarizes the findings of a literature survey carried out to assess the future world supply of and demand for titanium, copper and lead. These metals are candidate materials for the fabrication of containers for the immobilization and disposal of Canada's nuclear used-fuel waste for a reference Used-fuel Disposal Centre. Such a facility may begin operation by approximately 2020, and continue for about 40 years. The survey shows that the world has abundant supplies of titanium minerals (mostly in the form of ilmenite), which are expected to last up to at least 2110. However, for copper and lead the balance between supply and demand may warrant increased monitoring beyond the year 2000. A number of factors that can influence future supply and demand are discussed in the report

  1. Final disposal of spent nuclear fuel in Finnish bedrock. Olkiluoto site report

    International Nuclear Information System (INIS)

    Anttila, P.; Ahokas, H.; Front, K.

    1999-06-01

    Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Haestholmen in Loviisa, Kivetty in Aeaenekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Olkiluoto. The bedrock of the Olkiluoto site consists of Svecofennian metasediments and platonic rocks, 1800-1900 million years in age. Migmatitic mica gneiss is the most abundant rock type, and is intruded by foliated tonalites and granodiorites and massive coarse-grained granites and pegmatites. Five successive plastic deformation phases have been defined. In total, 30 bedrock structures (R-structures) have been modelled at the site. Most of these represent steeply dipping fracture zones, but several sub-horizontal zones, gently dipping to the SE, have also been identified. The rock mass between the fracture zones represents what is termed 'intact rock', which is typically hard, unweathered and sparsely fractured. The R-structures are generally hydraulically more conductive than the intact rock and their mean transmissivity is 3 x 10 -7 m 2 /s. The corresponding mean of the hydraulic conductivity values for the intact rock measured using a 2 m packer interval, is 8 x 10 -13 m/s, if a lognormal distribution for all measured values is assumed. A clear decrease in hydraulic conductivity with depth has been found for the intact rock, and there seems to be a parallel decrease in the transmissivity of structures. In addition, the hydraulically conductive fractures seem to be more frequent and their transmissivities higher in the uppermost 100 - 200 m of the bedrock than at greater depths. The groundwater chemistry reflects the postglacial

  2. Final disposal of spent nuclear fuel in Finnish bedrock - Kivetty site report

    Energy Technology Data Exchange (ETDEWEB)

    Anttila, P. [Fortum Engineering Oy, Vantaa (Finland); Ahokas, H.; Front, K. [Fintact Oy (Finland)] [and others

    1999-06-01

    Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Haestholmen in Loviisa, Kivetty in Aeaenekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Kivetty. The bedrock of Kivetty belongs to the large Svecofennian granitoid complex of central Finland, about 1880 million years in age. The most common rock type is porphyritic granodiorite, which is cut by younger medium-grained granodiorite and porphyritic or even-grained granite. Minor bodies of gabbro, older than the porphyritic granodiorite, are also present. The granitoids show evidence of two deformation phases. Altogether 29 bedrock 'structures' (R-structures) have been modelled at the investigation site, most of them representing steeply dipping fracture zones. The rock mass between the fracture zones represents what is termed 'intact rock', which is typically hard, unweathered and sparsely fractured. The R-structures are generally hydraulically more conductive than the intact rock and their mean transmissivity is 1.3-10{sup -6} m{sup 2}/s. The corresponding mean of the hydraulic conductivity values for the intact rock, measured using a 2 m packer interval is 4*10{sup -11} m{sup 2}/s, if a lognormal distribution for all measured values is assumed. A clear decrease in hydraulic conductivity with depth has been found for the intact rock, and there seems to be a parallel decrease in the transmissivity of structures. In addition, the hydraulically conductive fractures seem to be more frequent and their transmissivities higher in the uppermost 100 - 200 m of the bedrock than at greater depths. The groundwater of

  3. Final disposal of spent nuclear fuel in Finnish bedrock. Olkiluoto site report

    Energy Technology Data Exchange (ETDEWEB)

    Anttila, P. [Fortum Engineering Oy, Vantaa (Finland); Ahokas, H. [Fintact Oy, Helsinki (Finland); Front, K. [VTT Communication and Infrastructure, Espoo (Finland)] [and others

    1999-06-01

    Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Haestholmen in Loviisa, Kivetty in Aeaenekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Olkiluoto. The bedrock of the Olkiluoto site consists of Svecofennian metasediments and platonic rocks, 1800-1900 million years in age. Migmatitic mica gneiss is the most abundant rock type, and is intruded by foliated tonalites and granodiorites and massive coarse-grained granites and pegmatites. Five successive plastic deformation phases have been defined. In total, 30 bedrock structures (R-structures) have been modelled at the site. Most of these represent steeply dipping fracture zones, but several sub-horizontal zones, gently dipping to the SE, have also been identified. The rock mass between the fracture zones represents what is termed `intact rock`, which is typically hard, unweathered and sparsely fractured. The R-structures are generally hydraulically more conductive than the intact rock and their mean transmissivity is 3 x 10{sup -7} m{sup 2}/s. The corresponding mean of the hydraulic conductivity values for the intact rock measured using a 2 m packer interval, is 8 x 10{sup -13} m/s, if a lognormal distribution for all measured values is assumed. A clear decrease in hydraulic conductivity with depth has been found for the intact rock, and there seems to be a parallel decrease in the transmissivity of structures. In addition, the hydraulically conductive fractures seem to be more frequent and their transmissivities higher in the uppermost 100 - 200 m of the bedrock than at greater depths. The groundwater chemistry reflects the

  4. Improved nuclear fuel element

    International Nuclear Information System (INIS)

    Klepfer, H.H.

    1974-01-01

    A nuclear fuel element is described which comprises: 1) an elongated clad container, 2) a layer of high lubricity material being disposed in and adjacent to the clad container, 3) a low neutron capture cross section metal liner being disposed in the clad container and adjacent to the layer, 4) a central core of a body of nuclear fuel material disposed in and partially filling the container and forming an internal cavity in the container, 5) an enclosure integrally secured and sealed at each end of the container, and a nuclear fuel material retaining means positioned in the cavity. (author)

  5. Evaluation of the recycling costs, as a disposal form of the spent nuclear fuel

    International Nuclear Information System (INIS)

    Ramirez S, J.R.; Alonso V, G.; Palacios, J.C.

    2006-01-01

    At the moment there are 2 BWR reactors operating in the Nuclear Power station of Laguna Verde in Mexico. At the end of the programmed life of the reactors (40 years) its will have completed 26 operation cycles, with will have 6712 spent fuel assemblies will be in the pools of the power station. Up to now, the decision on the destination of the high level wastes (spent nuclear fuel) it has not been determined in Mexico, the same as in other countries, adopting a politics of 'to wait to see that it happens in the world', in this respect, in the world two practical alternatives exist, one is to store the fuel in repositories designed for that end, another is reprocess the fuel to recycle the plutonium contained in it, both solutions have their particular technical and economic problematic. In this work it is evaluated from the economic point of view the feasibility of having the spent fuel, using the one recycled fuel, for that which thinks about a consistent scenario of a BWR reactor in which the fuel discharged in each operation cycle is reprocessed and its are built fuel assemblies of the MOX type to replace partly to the conventional fuel. This scenario shows an alternative to the indefinite storage of the high level radioactive waste. The found results when comparing from the economic point of view both options, show that the one recycled, even with the current costs of the uranium it is of the order of 7% more expensive that the option of storing the fuel in repositories constructed for that purpose. However the volumes of spent fuel decrease in 66%. (Author)

  6. AECB staff response to the environmental impact statement on the concept for disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    1995-07-01

    The Environmental Impact Statement (EIS) on the Concept for Disposal of Canada's Nuclear Fuel Waste was released in October 1994 (AECL,1994) in response to the guidelines issued in 1992 by a Panel formed to evaluate this concept (Federal Environmental Assessment Review Panel, 1992). This response is primarily a statement of deficiencies and thus focuses on the negative aspects of the EIS. The staff review of the EIS was based on the AECB mandate, which is to protect human health and the environment and as such was focused on technical issues in the EIS. These were performance assessment of the multiple barrier system, environmental impacts, concept feasibility, siting, transport and safety as well as general issues of regulatory policy and criteria. The EIS and its supporting documentation have been the sole basis used to judge whether AECB staff expectations of the EIS have been met. The staff response (Part II) considers whether an issue is addressed appropriately and adequately, while taking account of the generic and preliminary nature of the concept. The overall conclusion that AECB staff have drawn from the technical review of the EIS is that the EIS, by itself, does not adequately demonstrate the case for deep geological disposal for nuclear fuel waste. However, AECB staff believe that the EIS information, in combination with a variety of generic national and international assessments, has provided confidence that the deep geological disposal concept is safe and viable. 74 refs

  7. AECB staff response to the environmental impact statement on the concept for disposal of Canada`s nuclear fuel waste

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The Environmental Impact Statement (EIS) on the Concept for Disposal of Canada`s Nuclear Fuel Waste was released in October 1994 (AECL,1994) in response to the guidelines issued in 1992 by a Panel formed to evaluate this concept (Federal Environmental Assessment Review Panel, 1992). This response is primarily a statement of deficiencies and thus focuses on the negative aspects of the EIS. The staff review of the EIS was based on the AECB mandate, which is to protect human health and the environment and as such was focused on technical issues in the EIS. These were performance assessment of the multiple barrier system, environmental impacts, concept feasibility, siting, transport and safety as well as general issues of regulatory policy and criteria. The EIS and its supporting documentation have been the sole basis used to judge whether AECB staff expectations of the EIS have been met. The staff response (Part II) considers whether an issue is addressed appropriately and adequately, while taking account of the generic and preliminary nature of the concept. The overall conclusion that AECB staff have drawn from the technical review of the EIS is that the EIS, by itself, does not adequately demonstrate the case for deep geological disposal for nuclear fuel waste. However, AECB staff believe that the EIS information, in combination with a variety of generic national and international assessments, has provided confidence that the deep geological disposal concept is safe and viable. 74 refs.

  8. The Swedish Concept for Disposal of Spent Nuclear Fuel: Differences Between Vertical and Horizontal Waste Canister Emplacement

    International Nuclear Information System (INIS)

    Bennett, D.G.; Hicks, T.W.

    2005-10-01

    The Swedish Nuclear Power Inspectorate (SKI) is preparing for the review of licence applications related to the disposal of spent nuclear fuel. The Swedish Nuclear Fuel and Waste Management Company (SKB) refers to its proposals for the disposal of spent nuclear fuel as the KBS-3 concept. In the KBS-3 concept, SKB plans that, after 30 to 40 years of interim storage, spent fuel will be disposed of at a depth of about 500 m in crystalline bedrock, surrounded by a system of engineered barriers. The principle barrier to radionuclide release is a cylindrical copper canister. Within the copper canister, the spent fuel is supported by a cast iron insert. Outside the copper canister is a layer of bentonite clay, known as the buffer, which is designed to provide mechanical protection for the canisters and to limit the access of groundwater and corrosive substances to their surfaces. The bentonite buffer is also designed to sorb radionuclides released from the canisters, and to filter any colloids that may form within the waste. SKB is expected to base its forthcoming licence applications on a repository design in which the waste canisters are emplaced in vertical boreholes (KBS-3V). However, SKB has also indicated that it might be possible and, in some respects, beneficial to dispose of the waste canisters in horizontal tunnels (KBS-3H). There are many similarities between the KBS-3V and KBS-3H designs. There are, however, uncertainties associated with both of the designs and, when compared, both possess relative advantages and disadvantages. SKB has identified many of the key factors that will determine the evolution of a KBS-3H repository and has plans for research and development work in many of the areas where the differences between the KBS-3V and KBS-3H designs mean that they could be significant in terms of repository performance. With respect to the KBS-3H design, key technical issues are associated with: 1. The accuracy of deposition drift construction. 2. Water

  9. The potential for stress corrosion cracking of copper containers in a Canadian nuclear fuel waste disposal vault

    International Nuclear Information System (INIS)

    King, F.

    1996-09-01

    The potential for stress corrosion cracking (SCC) of copper nuclear fuel waste containers in a conceptual Canadian disposal vault has been assessed through a review of the literature and comparison of those environmental factors that cause SCC with the expected disposal environment. Stress-corrosion cracking appears to be an unlikely failure mode for Cu containers in a Canadian disposal vault because of a combination of environmental factors. Most importantly, there is only a relatively short period during which the containers will be undergoing strain when cracking should be possible at all, and then cracking is not expected because of the absence of known SCC agents, such as NH 3 , NO 2 - or organic acids. In addition, other environmental factors will mitigate SCC, namely, the presence of C1 - and its effect on film properties and the limited supply of oxidants. These arguments, to greater or lesser extent, apply to the three major mechanisms proposed for SCC of Cu alloys in aqueous solutions: film-rupture/anodic dissolution, tarnish rupture and film-induced cleavage. Detailed reviews of the SCC literature are presented as Appendices. The literature on the SCC of Cu (>99 wt.% Cu) is reviewed, including studies carried out in a number of countries under nuclear waste disposal conditions. Because of similarities with the behaviour of Cu, the more extensive literature on the SCC of α-brass in ammonia solutions is also reviewed. (author). 140 refs., 3 tabs., 25 figs

  10. Nuclear fuels

    International Nuclear Information System (INIS)

    Gangwani, Saloni; Chakrabortty, Sumita

    2011-01-01

    Nuclear fuel is a material that can be consumed to derive nuclear energy, by analogy to chemical fuel that is burned for energy. Nuclear fuels are the most dense sources of energy available. Nuclear fuel in a nuclear fuel cycle can refer to the fuel itself, or to physical objects (for example bundles composed of fuel rods) composed of the fuel material, mixed with structural, neutron moderating, or neutron reflecting materials. Long-lived radioactive waste from the back end of the fuel cycle is especially relevant when designing a complete waste management plan for SNF. When looking at long-term radioactive decay, the actinides in the SNF have a significant influence due to their characteristically long half-lives. Depending on what a nuclear reactor is fueled with, the actinide composition in the SNF will be different. The following paper will also include the uses. advancements, advantages, disadvantages, various processes and behavior of nuclear fuels

  11. The Nuclear Fuel Cycle

    International Nuclear Information System (INIS)

    2011-08-01

    This brochure describes the nuclear fuel cycle, which is an industrial process involving various activities to produce electricity from uranium in nuclear power reactors. The cycle starts with the mining of uranium and ends with the disposal of nuclear waste. The raw material for today's nuclear fuel is uranium. It must be processed through a series of steps to produce an efficient fuel for generating electricity. Used fuel also needs to be taken care of for reuse and disposal. The nuclear fuel cycle includes the 'front end', i.e. preparation of the fuel, the 'service period' in which fuel is used during reactor operation to generate electricity, and the 'back end', i.e. the safe management of spent nuclear fuel including reprocessing and reuse and disposal. If spent fuel is not reprocessed, the fuel cycle is referred to as an 'open' or 'once-through' fuel cycle; if spent fuel is reprocessed, and partly reused, it is referred to as a 'closed' nuclear fuel cycle.

  12. Final disposal of spent nuclear fuel in Finnish bedrock. Haestholmen site report

    International Nuclear Information System (INIS)

    Anttila, P.; Ahokas, H.; Front, K.

    1999-06-01

    Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Haestholmen in Loviisa, Kivetty in Aeaenekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Haestholmen. The Haestholmen area is located within the anorogenic Wiborg rapakivi granite batholith, about 1630 million years in age, representing one of the youngest rock formations in Finland. Wiborgite, pyterlite, porphyritic rapakivi granite and even-grained rapakivi granite are the rock types present. 25 bedrock structures have been modelled at the site. Most of them are steeply-dipping fracture zones trending NW-SE and NE-SW, but several sub-horizontal zones, mainly dipping to the N-NE and the SW, are also present. The rock mass between the fracture zones represents what is termed 'intact rock', which is typically hard, unweathered and sparsely fractured. The bedrock structures are generally hydraulically more conductive than the intact rock and their mean transmissivity is 8 x 10 -6 m 2 /s or 1.3 x 10 -6 m 2 /s, depending on how structures are defined. The corresponding mean of the hydraulic conductivity values measured for the intact rock using a 2 m packer interval is 1 x 10 -12 m/s, if a lognormal distribution for all measured values is assumed. A clear decrease in hydraulic conductivity with depth has been found in the intact rock. In addition, the hydraulically conductive fractures seem to be more frequent and their transmissivities higher in the uppermost 100-200 m of the bedrock than at greater depths. The groundwater chemistry reflects the post-glacial history of the island of Haestholmen, which rose from the Baltic Sea some

  13. Final disposal of spent nuclear fuel in Finnish bedrock. Haestholmen site report

    Energy Technology Data Exchange (ETDEWEB)

    Anttila, P. [Fortum Engineering Oy, Vantaa (Finland); Ahokas, H. [Fintact Oy, Helsinki (Finland); Front, K. [VTT Communities and Infrastructure, Espoo (Finland)

    1999-06-01

    Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Haestholmen in Loviisa, Kivetty in Aeaenekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Haestholmen. The Haestholmen area is located within the anorogenic Wiborg rapakivi granite batholith, about 1630 million years in age, representing one of the youngest rock formations in Finland. Wiborgite, pyterlite, porphyritic rapakivi granite and even-grained rapakivi granite are the rock types present. 25 bedrock structures have been modelled at the site. Most of them are steeply-dipping fracture zones trending NW-SE and NE-SW, but several sub-horizontal zones, mainly dipping to the N-NE and the SW, are also present. The rock mass between the fracture zones represents what is termed `intact rock`, which is typically hard, unweathered and sparsely fractured. The bedrock structures are generally hydraulically more conductive than the intact rock and their mean transmissivity is 8 x 10{sup -6} m{sup 2}/s or 1.3 x 10{sup -6} m{sup 2}/s, depending on how structures are defined. The corresponding mean of the hydraulic conductivity values measured for the intact rock using a 2 m packer interval is 1 x 10{sup -12} m/s, if a lognormal distribution for all measured values is assumed. A clear decrease in hydraulic conductivity with depth has been found in the intact rock. In addition, the hydraulically conductive fractures seem to be more frequent and their transmissivities higher in the uppermost 100-200 m of the bedrock than at greater depths. The groundwater chemistry reflects the post-glacial history of the island of Haestholmen, which rose

  14. Nuclear fuel reprocessing and high level waste disposal: informational hearings. Volume V. Reprocessing. Part 2

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-03-08

    Testimony was presented by a four member panel on the commercial future of reprocessing. Testimony was given on the status of nuclear fuel reprocessing in the United States. The supplemental testimony and materials submitted for the record are included in this report. (LK)

  15. Nuclear fuel replacement device

    International Nuclear Information System (INIS)

    Ritz, W.C.; Robey, R.M.; Wett, J.F.

    1984-01-01

    A fuel handling arrangement for a liquid metal cooled nuclear reactor having a single rotating plug eccentric to the fuel core and a fuel handling machine radially movable along a slot in the plug with a transfer station disposed outside the fuel core but covered by the eccentric plug and within range of movement of said fuel handling machine to permit transfer of fuel assemblies between the core and the transfer station. (author)

  16. Toward a risk assessment of the spent fuel and high-level nuclear waste disposal system. Risk assessment requirements, literature review, methods evaluation: an interim report

    International Nuclear Information System (INIS)

    Hamilton, L.D.; Hill, D.; Rowe, M.D.; Stern, E.

    1986-04-01

    This report provides background information for a risk assessment of the disposal system for spent nuclear fuel and high-level radioactive waste (HLW). It contains a literature review, a survey of the statutory requirements for risk assessment, and a preliminary evaluation of methods. The literature review outlines the state of knowledge of risk assessment and accident consequence analysis in the nuclear fuel cycle and its applicability to spent fuel and HLW disposal. The survey of statutory requirements determines the extent to which risk assessment may be needed in development of the waste-disposal system. The evaluation of methods reviews and evaluates merits and applicabilities of alternative methods for assessing risks and relates them to the problems of spent fuel and HLW disposal. 99 refs

  17. Toward a risk assessment of the spent fuel and high-level nuclear waste disposal system. Risk assessment requirements, literature review, methods evaluation: an interim report

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, L.D.; Hill, D.; Rowe, M.D.; Stern, E.

    1986-04-01

    This report provides background information for a risk assessment of the disposal system for spent nuclear fuel and high-level radioactive waste (HLW). It contains a literature review, a survey of the statutory requirements for risk assessment, and a preliminary evaluation of methods. The literature review outlines the state of knowledge of risk assessment and accident consequence analysis in the nuclear fuel cycle and its applicability to spent fuel and HLW disposal. The survey of statutory requirements determines the extent to which risk assessment may be needed in development of the waste-disposal system. The evaluation of methods reviews and evaluates merits and applicabilities of alternative methods for assessing risks and relates them to the problems of spent fuel and HLW disposal. 99 refs.

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

    International Nuclear Information System (INIS)

    Motiejunas, S.; Poskas, P.

    2005-01-01

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

  19. Final disposal of nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Anon,

    1995-10-01

    The nuclear industry argues that high level radioactive waste can be safely disposed of in deep underground repositories. As yet, however, no such repositories are in use and the amount of spent nuclear fuel in ponds and dry storage is steadily increasing. Although the nuclear industry further argues that storage is a safe option for up to 50 years and has the merit of allowing the radioactivity of the fuel to decay to a more manageable level, the situation seems to be far from ideal. The real reasons for procrastination over deep disposal seem to have as much to do with politics as safe technology. The progress of different countries in finding a solution to the final disposal of high level waste is examined. In some, notably the countries of the former Soviet Union, cost is a barrier; in others, the problem has not yet been faced. In these countries undertaking serious research into deep disposal there has been a tendency, in the face of opposition from environmental groups, to retreat to sites close to existing nuclear installations and to set up rock laboratories to characterize them. These sites are not necessarily the best geologically, but the laboratories may end up being converted into actual repositories because of the considerable financial investment they represent. (UK).

  20. Final disposal of nuclear waste

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    The nuclear industry argues that high level radioactive waste can be safely disposed of in deep underground repositories. As yet, however, no such repositories are in use and the amount of spent nuclear fuel in ponds and dry storage is steadily increasing. Although the nuclear industry further argues that storage is a safe option for up to 50 years and has the merit of allowing the radioactivity of the fuel to decay to a more manageable level, the situation seems to be far from ideal. The real reasons for procrastination over deep disposal seem to have as much to do with politics as safe technology. The progress of different countries in finding a solution to the final disposal of high level waste is examined. In some, notably the countries of the former Soviet Union, cost is a barrier; in others, the problem has not yet been faced. In these countries undertaking serious research into deep disposal there has been a tendency, in the face of opposition from environmental groups, to retreat to sites close to existing nuclear installations and to set up rock laboratories to characterize them. These sites are not necessarily the best geologically, but the laboratories may end up being converted into actual repositories because of the considerable financial investment they represent. (UK)

  1. An assessment of the long-term impact of chemically toxic contaminants from the disposal of nuclear fuel waste

    International Nuclear Information System (INIS)

    Goodwin, B.W.; Garisto, N.C.; Barnard, J.W.

    1987-01-01

    This paper presents a study on the potential for impact on man of chemically toxic contaminants associated with the Canadian concept for the disposal of nuclear fuel waste. The elements of concern are determined through a series of screening criteria such as elemental abundances and solubilities. A systems variability analysis approach is then used to predict the possible concentrations of these elements that may arise in the biosphere. These concentrations are compared with environmental guidelines such as permissible levels in drinking water. Conclusions are made regarding the potential for the chemically toxic contaminants to have an impact on man. 54 refs

  2. Policies, strategies and systems for the disposal of spent nuclear fuel; Principer, strategier och system foer slutligt omhaendertagande av anvaent kaernbraensle

    Energy Technology Data Exchange (ETDEWEB)

    Grundfelt, Bertil (Kemakta Konsult AB (Sweden))

    2010-12-15

    In this report an up-to-date account is made of the status of different principles, strategies and systems for the management and disposal of spent nuclear fuel. As large scale use of nuclear power for the production of electricity began in the 1960s and 1970s, studies of various principles and strategies for the management of the spent nuclear fuel were initialised. In particular in the USA, comprehensive studies were conducted of all strategies described in this report

  3. Investigations of possibilities to dispose of spent nuclear fuel in Lithuania: a model case. Volume 1, Suitability of Geological Environment in Lithuania for Disposal of Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    Motiejunas, S.; Satkunas, J.

    2005-01-01

    This Volume contains an overview of geological structure with respect to its relevance for waste disposal conditions and characteristics of crystalline rocks in Lithuania with respect to its relevance for waste disposal. The most prospective rock types are represented by cratonic (anorogenic) granitoid intrusions that in some places compose rather large massifs. These rocks are the least damaged by tectonic activity. Furthermore, the lithology variations at short distances are only minor that makes exploration much easier. Yet, other rock types (gneisses, mafic intrusions, migmatites) compose someplace only weakly fractured blocks that also may be prospective for repository

  4. Nuclear waste disposal

    International Nuclear Information System (INIS)

    Lindblom, U.; Gnirk, P.

    1982-01-01

    The subject is discussed under the following headings: the form and final disposal of nuclear wastes; the natural rock and groundwater; the disturbed rock and the groundwater; long-term behavior of the rock and the groundwater; nuclear waste leakage into the groundwater; what does it all mean. (U.K.)

  5. Corrosion resistance of canisters for final disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Mattsson, E.

    1979-01-01

    A group of Swedish scientists has evaluated from the corrosion point of view three alternative canister types for final disposal of waste from nuclear reactors in boreholes in rock 500 m below ground. Titanium canisters with a wall-thickness of 6 mm and 100 mm thick lead lining have been estimated to have a life of at least thousands of years, and probably tens of thousands of years. Copper canisters with 200-mm-thick walls would last for hundreds of thousands of years. The third type, α-alumina sintered under isostatic pressure, is a very promising canister material

  6. Room at the Mountain: Estimated Maximum Amounts of Commercial Spent Nuclear Fuel Capable of Disposal in a Yucca Mountain Repository

    International Nuclear Information System (INIS)

    Kessler, John H.; Kemeny, John; King, Fraser; Ross, Alan M.; Ross, Benjamen

    2006-01-01

    The purpose of this paper is to present an initial analysis of the maximum amount of commercial spent nuclear fuel (CSNF) that could be emplaced into a geological repository at Yucca Mountain. This analysis identifies and uses programmatic, material, and geological constraints and factors that affect this estimation of maximum amount of CSNF for disposal. The conclusion of this initial analysis is that the current legislative limit on Yucca Mountain disposal capacity, 63,000 MTHM of CSNF, is a small fraction of the available physical capacity of the Yucca Mountain system assuming the current high-temperature operating mode (HTOM) design. EPRI is confident that at least four times the legislative limit for CSNF (∼260,000 MTHM) can be emplaced in the Yucca Mountain system. It is possible that with additional site characterization, upwards of nine times the legislative limit (∼570,000 MTHM) could be emplaced. (authors)

  7. Advisory group meeting on safeguards related to final disposal of nuclear material in waste and spent fuel

    International Nuclear Information System (INIS)

    1988-07-01

    This paper is primarily concerned with Section 11 of INFCIRC/153 which provides for the possible termination of safeguards based on a determination that the nuclear material in question has been consumed, has been diluted, or has become practicably irrecoverable. Two distinctly different categories of nuclear material have been suggested for possible termination of safeguards based on a determination that the nuclear material has become practicably irrecoverable: One relates to a variety of low concentration waste materials, meaning thereby materials which the State or plant operator considers to be of questionable economic recoverability and the other relates to the spent fuel placed in facilities described as ''permanent repositories'' which are at least claimed to represent ''final disposal'' facilities and are candidates for a possible determination of practicably irrecoverable. 26 refs, tabs

  8. Experimental Investigation of Burnup Credit for Safe Transport, Storage, and Disposal of Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    Harms, Gary A.; Helmick, Paul H.; Ford, John T.; Walker, Sharon A.; Berry, Donald T.; Pickard, Paul S.

    2004-01-01

    This report describes criticality benchmark experiments containing rhodium that were conducted as part of a Department of Energy Nuclear Energy Research Initiative project. Rhodium is an important fission product absorber. A capability to perform critical experiments with low-enriched uranium fuel was established as part of the project. Ten critical experiments, some containing rhodium and others without, were conducted. The experiments were performed in such a way that the effects of the rhodium could be accurately isolated. The use of the experimental results to test neutronics codes is demonstrated by example for two Monte Carlo codes. These comparisons indicate that the codes predict the behavior of the rhodium in the critical systems within the experimental uncertainties. The results from this project, coupled with the results of follow-on experiments that investigate other fission products, can be used to quantify and reduce the conservatism of spent nuclear fuel safety analyses while still providing the necessary level of safety

  9. The effect of organic matter in clay sealing materials on the performance of a nuclear fuel waste disposal vault

    International Nuclear Information System (INIS)

    Oscarson, D.W.; Stroes-Gascoyne, S.; Cheung, S.C.H.

    1986-12-01

    The potential effect of organic matter in clay sealing materials on the performance of a nuclear fuel waste disposal vault was examined. The available data indicate that the engineering properties of clays are not significantly affected by the relatively low levels of organic matter (< 1.2 wt.%) present in the clay sealing materials. Complexing of radionuclides by organic substances that are released from the clay sealing materials or produced by microorganisms will likely inhibit rather than promote radionuclide mobility in the compacted sealing materials because of the relatively large size of organic complexing species. Decreasing the level of organic matter in the clay sealing materials will not eliminate microorganisms, and perhaps not decrease their numbers significantly, because chemolithotrophic microorganisms (microorganisms that utilize inorganic forms of C) will be present in a disposal vault. Furthermore, an examination of the nutrient budget in a disposal vault indicates that N, rather than C, will likely be the limiting nutrient for microbial growth. Finally, there is not suitable, proven method for decreasing the level of organic matter in the large amounts of clay needed to seal a vault. It is concluded that the organic matter present in the clay sealing material will not adversely affect the performance of a disposal vault

  10. Modelling of thermally driven groundwater flow in a facility for disposal of spent nuclear fuel in deep boreholes

    Energy Technology Data Exchange (ETDEWEB)

    Marsic, Nico; Grundfelt, Bertil [Kemakta Konsult AB, Stockholm (Sweden)

    2013-09-15

    In this report calculations are presented of buoyancy driven groundwater flow caused by the emission of residual heat from spent nuclear fuel deposited in deep boreholes from the ground surface in combination with the natural geothermal gradient. This work has been conducted within SKB's programme for evaluation of alternative methods for final disposal of spent nuclear fuel. The basic safety feature of disposal of spent nuclear fuel in deep boreholes is that the groundwater at great depth has a higher salinity, and hence a higher density, than more superficial groundwater. The result of this is that the deep groundwater becomes virtually stagnant. The study comprises analyses of the effects of different inter-borehole distances as well as the effect of different permeabilities in the backfill and sealing materials in the borehole and of different shapes of the interface between fresh and saline groundwater. The study is an update of a previous study published in 2006. In the present study, the facility design proposed by Sandia National Laboratories has been studied. In this design, steel canisters containing two BWR elements or one PWR element are stacked on top of each other between 3 and 5 kilometres depth. In order to host all spent fuel from the current Swedish nuclear programme, about 80 such holes are needed. The model used in this study comprises nine boreholes spaced 100 metres alternatively 50 metres apart in a 3{Chi}3 matrix. In one set of calculations the salinity in the groundwater was assumed to increase from zero above 700 metres depth to 10% by weight at 1500 metres depth and below. In another set, a sharper salinity gradient was applied in which the salinity increased from 0 to 10% between 1400 and 1500 metres depth. A geothermal gradient of 16 deg C/km was applied. The heat output from the spent fuel was assumed to decrease by time in manner consistent with the radioactive decay in the fuel. When the inter-borehole distance decreased from

  11. Handling and disposal of SP-100 ground test nuclear fuel and equipment

    International Nuclear Information System (INIS)

    Wilson, C.E.; Potter, J.D.; Hodgson, R.D.

    1990-05-01

    The post SP-100 reactor testing period will focus on defueling the reactor, packaging the various radioactive waste forms, and shipping this material to the appropriate locations. Remote-handling techniques will be developed to defuel the reactor. Packaging the spent fuel and activated reactor components is a challenge in itself. This paper presents an overview of the strategy, methods, and equipment that will be used during the closeout phase of nuclear testing

  12. Handling and disposal of SP-100 ground test nuclear fuel and equipment

    International Nuclear Information System (INIS)

    Wilson, C.E.; Potter, J.D.; Hodgson, R.D.

    1991-01-01

    The post SP-100 reactor testing period will focus on defueling the reactor, packaging the various radiactive waste forms, and shipping this material to the appropriate locations. Remote-handling techniques will be developed to defuel the reactor. Packaging the spent fuel and activated reactor components is a challenge in itself. This paper presents an overview of the strategy, methods, and equipment that will be used during the closeout phase of nuclear testing

  13. Nuclear waste disposal

    International Nuclear Information System (INIS)

    Hare, Tony.

    1990-01-01

    The Save Our Earth series has been designed to appeal to the inquiring minds of ''planet-friendly'' young readers. There is now a greater awareness of environmental issues and an increasing concern for a world no longer able to tolerate the onslaught of pollution, the depletion of natural resources and the effects of toxic chemicals. Each book approaches a specific topic in a way that is exciting and thought-provoking, presenting the facts in a style that is concise and appropriate. The series aims to demonstrate how various environmental subjects relate to our lives, and encourages the reader to accept not only responsibility for the planet, but also for its rescue and restoration. This volume, on nuclear waste disposal, explains how nuclear energy is harnessed in a nuclear reactor, what radioactive waste is, what radioactivity is and its effects, and the problems and possible solutions of disposing of nuclear waste. An awareness of the dangers of nuclear waste is sought. (author)

  14. Impact Force Applied on the Spent Nuclear Fuel Disposal Canister that Accidentally Drops and Collides onto the Ground

    International Nuclear Information System (INIS)

    Kwon, Young Joo

    2016-01-01

    In this paper, a mathematical methodology was theoretically studied to obtain the impact force caused by the collision between rigid bodies. This theoretical methodology was applied to compute the impact force applied on the spent nuclear fuel disposal canister that accidentally drops and collides onto the ground. From this study, the impact force required to ensure a structurally safe canister design was theoretically formulated. The main content of the theoretical study concerns the rigid body kinematics and equation of motion during collision between two rigid bodies. On the basis of this study, a general impact theory to compute the impact force caused by the collision between two bodies was developed. This general impact theory was applied to theoretically formulate the approximate mathematical solution of the impact force that affects the spent nuclear fuel disposal canister that accidentally falls to the ground. Simultaneously, a numerical analysis was performed using the computer code to compute the numerical solution of the impact force, and the numerical result was compared with the approximate mathematical solution

  15. Fuel corrosion processes under waste disposal conditions

    International Nuclear Information System (INIS)

    Shoesmith, D.W.

    2000-01-01

    The release of the majority of radionuclides from spent nuclear fuel under permanent disposal conditions will be controlled by the rate of dissolution of the UO 2 fuel matrix. In this manuscript the mechanism of the coupled anodic (fuel dissolution) and cathodic (oxidant reduction) reactions which constitute the overall fuel corrosion process is reviewed, and the many published observations on fuel corrosion under disposal conditions discussed. The primary emphasis is on summarizing the overall mechanistic behaviour and establishing the primary factors likely to control fuel corrosion. Included are discussions on the influence of various oxidants including radiolytic ones, pH, temperature, groundwater composition, and the formation of corrosion product deposits. The relevance of the data recorded on unirradiated UO 2 to the interpretation of spent fuel behaviour is included. Based on the review, the data used to develop fuel corrosion models under the conditions anticipated in Yucca Mountain (NV, USA) are evaluated

  16. Chemistry of nuclear waste disposal

    International Nuclear Information System (INIS)

    Zimmer, E.

    1981-01-01

    In extractive purification of the low-enriched uranium fuel element (UO 2 -particle fuel element with SiC coating) no problems arise in the PUREX-process which have not already been solved when reprocessing LWR-type reactor and breeder fuel elements. Concerning the HTR-type reactor fuel elements containing thorium, there are two process cycles behind the head end; the pure U-235 is reprocessed in the same manner as the low-enriched uranium fuel, and the thorium, which is the bigger fraction, is reprocessed together with U-233 in the same manner as the mixed oxides. Only the CO 2 -off gas system, which contains krypton and carbon 14, leads to difficulties in nuclear waste disposal. (DG) [de

  17. Fusion option to dispose of spent nuclear fuel and transuranic elements

    International Nuclear Information System (INIS)

    Gohar, Y.

    2000-01-01

    The fusion option is examined to solve the disposition problems of the spent nuclear fuel and the transuranic elements. The analysis of this report shows that the top rated solution, the elimination of the transuranic elements and the long-lived fission products, can be achieved in a fusion reactor. A 167 MW of fusion power from a D-T plasma for sixty years with an availability factor of 0.75 can transmute all the transuranic elements and the long-lived fission products of the 70,000 tons of the US inventory of spent nuclear fuel generated up to the year 2015. The operating time can be reduced to thirty years with use of 334 MW of fusion power, a system study is needed to define the optimum time. In addition, the fusion solution eliminates the need for a geological repository site, which is a major advantage. Meanwhile, such utilization of the fusion power will provide an excellent opportunity to develop fusion energy for the future. Fusion blankets with a liquid carrier for the transuranic elements can achieve a transmutation rate for the transuranic elements up to 80 kg/MW.y of fusion power with k eff of 0.98. In addition, the liquid blankets have several advantages relative to the other blanket options. The energy from this transmutation is utilized to produce revenue for the system. Molten salt (Flibe) and lithium-lead eutectic are identified as the most promising liquids for this application, both materials are under development for future fusion blanket concepts. The Flibe molten salt with transuranic elements was developed and used successfully as nuclear fuel for the molten salt breeder reactor in the 1960's

  18. Castor oil polyurethane as a coating option for spent nuclear fuel disposal containment

    Energy Technology Data Exchange (ETDEWEB)

    Mortley, A.; Bonin, H.W.; Bui, V.T. [Dept. of Chemistry and Chemical Engineering, Royal Military College of Canada, Kingston, Ontario (Canada)

    2009-07-01

    Castor oil polyurethane (COPU) coatings are being proposed as an additional barrier in the design of the copper containers to store spent nuclear fuel in Canada. The present work investigates the variation in the physicomechanical properties of two COPUs, based on an aliphatic and aromatic diisocyanate, as a function of ionizing radiation dose and dose rate. The changes in physicomechanical properties have shown that radiation, regardless of dose rate and isocyanate structure, increases the values of the modulus and the ultimate tensile strength when compared with those of the unirradiated samples, with aromatic based polyurethanes being more susceptible to variation than aliphatic based ones. (author)

  19. Castor oil polyurethane as a coating option for spent nuclear fuel disposal containment

    International Nuclear Information System (INIS)

    Mortley, A.; Bonin, H.W.; Bui, V.T.

    2009-01-01

    Castor oil polyurethane (COPU) coatings are being proposed as an additional barrier in the design of the copper containers to store spent nuclear fuel in Canada. The present work investigates the variation in the physicomechanical properties of two COPUs, based on an aliphatic and aromatic diisocyanate, as a function of ionizing radiation dose and dose rate. The changes in physicomechanical properties have shown that radiation, regardless of dose rate and isocyanate structure, increases the values of the modulus and the ultimate tensile strength when compared with those of the unirradiated samples, with aromatic based polyurethanes being more susceptible to variation than aliphatic based ones. (author)

  20. Nuclear fuel

    International Nuclear Information System (INIS)

    D Hondt, P.

    1998-01-01

    The research and development programme on nuclear fuel at the Belgian Nuclear Research Centre SCK/CEN is described. The objective of this programme is to enhance the quantitative prediction of the operational limits of nuclear fuel and to assess the behaviour of fuel under incidental and accidental conditions. Progress is described in different domains including the modelling of fission gas release in LWR fuel, thermal conductivity, basic physical phenomena, post-irradiation examination for fuel performance assessment, and conceptual studies of incidental and accidental fuel experiments

  1. Key natural analogue input required to build a safety case for direct disposal of spent nuclear fuel in Japan

    Energy Technology Data Exchange (ETDEWEB)

    McKinley, I.G.; Hardie, S.M.L.; Klein, E. [MCM Consulting, Baden-Dättwil (Switzerland); Kawamura, H. [Obayashi Corporation, Nuclear Facilities Division, Tokyo (Japan); Beattie, T.M. [MCM Consulting, Bristol (United Kingdom)

    2015-06-15

    Natural analogues have been previously used to support the safety case for direct disposal of spent nuclear fuel, but the focus of such work was very dependent on the key barriers of specific national disposal concepts. Investigations of the feasibility of such disposal in Japan are at an early stage but, nevertheless, it is clear that building a robust safety case will be very challenging and would benefit from focused support from natural analogue studies—both in terms of developing/testing required models and, as importantly, presenting safety arguments to a wide range of stakeholders. This paper identifies key analogues that support both longevity and spread of failure times of massive steel overpacks, the effectiveness of buffering of radiolytic oxidants and the chemical and physical mechanisms retarding release of radionuclides from the engineered barriers. It is concluded that, for countries like Japan where performance needs to be assessed as realistically as possible, natural analogues can complement the existing laboratory and theoretical knowledge base and contribute towards development of a robust safety case. (authors)

  2. Residual radioactivity investigation and radiological assessments for self-disposal of concrete waste in nuclear fuel processing facility

    International Nuclear Information System (INIS)

    Seol, Jeung Gun; Ryu, Jae Bong; Cho, Suk Ju; Yoo, Sung Hyun; Song, Jung Ho; Baek, Hoon; Kim, Seong Hwan; Shin, Jin Seong; Park, Hyun Kyoun

    2007-01-01

    In this study, domestic regulatory requirement was investigated for self-disposal of concrete waste from nuclear fuel processing facility. And after self-disposal as landfill or recycling/reuse, the exposure dose was evaluated by RESRAD Ver. 6.3 and RESRAD BUILD Ver. 3.3 computing code for radiological assessments of the general public. Derived clearance level by the result of assessments for the exposure dose of the general public is 0.1071Bq/g (3.5% enriched uranium) for landfill and 0.05515 Bq/cm 2 (5% enriched uranium) for recycling/reuse respectively. Also, residual radioactivity of concrete waste after decontamination was investigated in this study. The result of surface activity is 0.01Bq/cm 2 for emitter and the result of radionuclide analysis for taken concrete samples from surface of concrete waste is 0.0297Bq/g for concentration of 238 U, below 2w/o for enrichment of 235 U and 0.0089Bq/g for artificial contamination of 238 U respectively. Therefore, radiological hazard of concrete waste by self-disposal as landfill and recycling/reuse is below clearance level to comply with clearance criterion provided for Notice No. 2001-30 of the MOST and Korea Atomic Energy Act

  3. Posiva's application for a decision in principle concerning a disposal facility for spent nuclear fuel. STUK's statement and preliminary safety appraisal

    International Nuclear Information System (INIS)

    Ruokola, E.

    2000-03-01

    In May 1999, Posiva Ltd submitted to the Government an application, pursuant to the Nuclear Energy Act, for a Decision in Principle on a disposal facility for spent nuclear fuel from the Finnish nuclear power plants. The Ministry of Trade and Industry requested the Radiation and Nuclear Safety Authority (STUK) to draw up a preliminary safety appraisal concerning the proposed disposal facility. In the beginning of this report, STUK's statement to the Ministry and Industry concerning the proposed disposal facility is given. In that statement, STUK concludes that the Decision in Principle is currently justified from the standpoint of safety. The statement is followed by a safety appraisal, where STUK deems, how the proposed disposal concept, site and facility comply with the safety requirements included in the Government's Decision (478/1999). STUK's preliminary safety appraisal was supported by contributions from a number of outside experts. A collective opinion by an international group of ten distinguished experts is appended to this report. (orig.)

  4. SKB 91. Final disposal of spent nuclear fuel. Importance of the bedrock for safety

    International Nuclear Information System (INIS)

    1992-05-01

    The safety of a deep repository for spent nuclear fuel has been assessed in this report. The spent fuel is assumed to be encapsulated in a copper canister and deposited at a depth of 600 m in the bedrock. The primary purpose has been to shed light on the importance of the geological features of the site for the safety of a final repository. The assessment shows that the encapsulated fuel will, in all likelihood, be kept isolated from the groundwater for millions of years. This is considerably longer than the more than 100 000 years that are required in order for the toxicity of the waste to have declined to a level equivalent to that of rich uranium ores. However, in order to be able to study the role of the rock as a barrier to the dispersal of radioactive materials, calculations have been carried out under the assumption that waste canisters leak. The results show that the safety of a carefully designed repository is only affected to a small extent by the ability of the rock to retain the escaping radionuclides. The primary role of the rock is to provide stable mechanical and chemical conditions in the repository over a long period of time so that the function of the engineered barriers is not jeopardized. (187 refs.) (au)

  5. Nuclear fuel elements

    International Nuclear Information System (INIS)

    Nakai, Keiichi

    1983-01-01

    Purpose: To decrease the tensile stresses resulted in a fuel can as well as prevent decladding of fuel pellets into the bore holes by decreasing the inner pressure within the nuclear fuel element. Constitution: A fuel can is filled with hollow fuel pellets, inserted with a spring for retaining the hollow fuel pellets with an appropriate force and, thereafter, closely sealed at the both ends with end plugs. A cylindrical body is disposed into the bore holes of the hollow fuel pellets. Since initial sealing gases and/or gaseous nuclear fission products can thus be excluded from the bore holes where the temperature is at the highest level, the inner pressure of the nuclear fuel element can be reduced to decrease the tensile strength resulted to the fuel can. Furthermore, decladding of fuel pellets into the bore holes can be prevented. (Moriyama, K.)

  6. Nuclear Dynamics Consequence Analysis (NDCA) for the Disposal of Spent Nuclear Fuel in an Underground Geologic Repository--Volume 2: Methodology and Results

    International Nuclear Information System (INIS)

    Taylor, L.L.; Wilson, J.R.; Sanchez, L.C.; Aguilar, R.; Trellue, H.R.; Cochrane, K.; Rath, J.S.

    1998-01-01

    The US Department of Energy Office of Environmental Management's (DOE/EM's) National Spent Nuclear Fuel Program (NSNFP), through a collaboration between Sandia National Laboratories (SNL) and Idaho National Engineering and Environmental Laboratory (INEEL), is conducting a systematic Nuclear Dynamics Consequence Analysis (NDCA) of the disposal of SNFs in an underground geologic repository sited in unsaturated tuff. This analysis is intended to provide interim guidance to the DOE for the management of the SNF while they prepare for final compliance evaluation. This report presents results from a Nuclear Dynamics Consequence Analysis (NDCA) that examined the potential consequences and risks of criticality during the long-term disposal of spent nuclear fuel owned by DOE-EM. This analysis investigated the potential of post-closure criticality, the consequences of a criticality excursion, and the probability frequency for post-closure criticality. The results of the NDCA are intended to provide the DOE-EM with a technical basis for measuring risk which can be used for screening arguments to eliminate post-closure criticality FEPs (features, events and processes) from consideration in the compliance assessment because of either low probability or low consequences. This report is composed of an executive summary (Volume 1), the methodology and results of the NDCA (Volume 2), and the applicable appendices (Volume 3)

  7. Nuclear Dynamics Consequence Analysis (NDCA) for the Disposal of Spent Nuclear Fuel in an Underground Geologic Repository--Volume 2: Methodology and Results

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, L.L.; Wilson, J.R.; Sanchez, L.C.; Aguilar, R.; Trellue, H.R.; Cochrane, K.; Rath, J.S.

    1998-10-01

    The US Department of Energy Office of Environmental Management's (DOE/EM's) National Spent Nuclear Fuel Program (NSNFP), through a collaboration between Sandia National Laboratories (SNL) and Idaho National Engineering and Environmental Laboratory (INEEL), is conducting a systematic Nuclear Dynamics Consequence Analysis (NDCA) of the disposal of SNFs in an underground geologic repository sited in unsaturated tuff. This analysis is intended to provide interim guidance to the DOE for the management of the SNF while they prepare for final compliance evaluation. This report presents results from a Nuclear Dynamics Consequence Analysis (NDCA) that examined the potential consequences and risks of criticality during the long-term disposal of spent nuclear fuel owned by DOE-EM. This analysis investigated the potential of post-closure criticality, the consequences of a criticality excursion, and the probability frequency for post-closure criticality. The results of the NDCA are intended to provide the DOE-EM with a technical basis for measuring risk which can be used for screening arguments to eliminate post-closure criticality FEPs (features, events and processes) from consideration in the compliance assessment because of either low probability or low consequences. This report is composed of an executive summary (Volume 1), the methodology and results of the NDCA (Volume 2), and the applicable appendices (Volume 3).

  8. Nuclear Dynamics Consequence Analysis (NDCA) for the Disposal of Spent Nuclear Fuel in an Underground Geologic Repository--Volume 1: Executive Summary

    International Nuclear Information System (INIS)

    Taylor, L.L.; Wilson, J.R.; Sanchez, L.Z.; Aguilar, R.; Trellue, H.R.; Cochrane, K.; Rath, J.S.

    1998-01-01

    The US Department of Energy Office of Environmental Management's (DOE/EM's) National Spent Nuclear Fuel Program (NSNFP), through a collaboration between Sandia National Laboratories (SNL) and Idaho National Engineering and Environmental Laboratory (INEEL), is conducting a systematic Nuclear Dynamics Consequence Analysis (NDCA) of the disposal of SNFs in an underground geologic repository sited in unsaturated tuff. This analysis is intended to provide interim guidance to the DOE for the management of the SNF while they prepare for final compliance evaluation. This report presents results from a Nuclear Dynamics Consequence Analysis (NDCA) that examined the potential consequences and risks of criticality during the long-term disposal of spent nuclear fuel owned by DOE-EM. This analysis investigated the potential of post-closure criticality, the consequences of a criticality excursion, and the probability frequency for post-closure criticality. The results of the NDCA are intended to provide the DOE-EM with a technical basis for measuring risk which can be used for screening arguments to eliminate post-closure criticality FEPs (features, events and processes) from consideration in the compliance assessment because of either low probability or low consequences. This report is composed of an executive summary (Volume 1), the methodology and results of the NDCA (Volume 2), and the applicable appendices (Volume 3)

  9. AECB staff response to the environmental impact statement on the concept for disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    1995-07-01

    The Environmental Impact Statement on the Concept for Disposal of Canada's Nuclear Fuel Waste was released in October 1994 in response to the guidelines issued in 1992 by a panel formed to evaluate this concept (Federal Environmental Assessment Review Panel, 1992). This response is primarily a statement of deficiencies and thus focuses on the negative aspects of the Environmental Impact Statement (EIS). The staff review of the EIS was based on the AECB mandate, which is to protect human health and the environment and as such was focused on technical issues in the EIS. These were performance assessment of the multiple barrier system, environmental impacts, concept feasibility, siting, transport and safety as well as general issues o f regulatory policy and criteria. 30 refs

  10. Technical assistance to AECL: electron beam welding of thick-walled copper containers for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Maak, P.Y.Y.

    1984-01-01

    This report describes the results of Phase Two of the copper electron beam welding project for the final closure of copper containers for nuclear fuel waste disposal. It has been demonstrated that single pass, electron beam square butt welds (depth of weld penetration > 25 mm) can be made without preheat in both electrolytic tough-pitch copper and oxygen-free copper plates. The present results show that oxygen-free copper exhibits better weldability than the electrolytic tough-pitch copper in terms of weld penetration and vulnerability to weld defects such as gas porosity, erratic metal overflow and blow holes. The results of ultrasonic inspection studies of the welds are also discussed

  11. A novel waste form for disposal of spent-nuclear-fuel reprocessing waste: A vitrifiable cement

    International Nuclear Information System (INIS)

    Gougar, M.L.D.; Scheetz, B.E.; Siemer, D.D.

    1999-01-01

    A cement capable of being hot isostatically pressed into a glass ceramic has been proposed as the waste form for spent-nuclear-fuel reprocessing wastes at the Idaho National Engineering and Environmental Laboratory (INEEL). This intermediate cement, with a composition based on that of common glasses, has been designed and tested. The cement formulations included mixed INEEL wastes, blast furnace slag, reactive silica, and INEEL soil or vermiculite, which were activated with potassium or sodium hydroxide. Following autoclave processing, the cements were characterized. X-ray diffraction analysis revealed three notable crystalline phases: quartz, calcite, and fluorite. Results of compressive strength testing ranged from 1452 and 4163 psi, exceeding the US Nuclear Regulatory Commission (NRC)-suggested standard of >500 psi. From American National Standards Institute/American Nuclear Society 16.1-1986 leach testing, effective diffusivities for Cs were determined to be on the order of 10 -11 to 10 -10 cm 2 /s and for Sr were 10 -12 cm 2 /s, which are four orders of magnitude less than diffusivities in some other radwaste materials. Average leach indices (LI) were 9.6 and 11.9 for Cs and Sr, respectively, meeting the NRC Standard of LI > 6. The 28-day Materials Characterization Center-1 leach testing resulted in normalized elemental mass losses between 0.63 and 28 g/(m 2 ·day) for Cs and between 0.34 and 0.70 g/(m 2 ·day) industry-accepted standard while Cs losses indicate a process sensitive parameter

  12. Geological site selection studies for the final disposal of spent nuclear fuel in Finland

    International Nuclear Information System (INIS)

    Salmi, M.; Vuorela, P.; Kuivamaeki, A.

    1985-10-01

    have been met with that should be avoided in the sites to be selected for the final disposal of nuclear waste

  13. Uraninite alteration in an oxidizing environment and its relevance to the disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Finch, R.; Ewing, R.

    1990-12-01

    Uraninite is a natural analogue for spent nuclear fuel because of similarities in structure and chemistry. Effective assessment of the long-term behavior of spent fuel in a geologic repository requires a knowledge of the corrosion products produced in that environment. Several important natural analogue sites are reviewed, illustrating a wide variety of environments from oxidizing to reducing, including, among others: Cigar Lake, Canada, a uraninite-bearing ore body at depth within a strictly reducing environment; the ore body has 'seen' extensive groundwater interaction with virtually no significant oxidation or mobilization of U apperent. Koongara, Australia is a highly altered uraninite-bearing ore body partially exposed to meteoric water; alteration at depth has resulted from interaction with groundwater having a somewhat reduced Eh compared to the surface. Uraninite, Pb-uranyl oxide hydrates and uranyl silicates control U solubility at depth; uranyl phosphates and U adsorption onto clays and FeMn-oxides control U solubility near the surface. Pocos de Caldas, Brazil displays a redox from moving through uraninite-bearing rocks near the surface and shows local remobilization of U. Oklo, Gabon, a uraninite- and coffinite-bearing ore body, locally affected by intense hydrothermal alteration during fission reactions, demonstrates restricted radionuclide and fission product transport within a reducing environment. A current study being conducted by the authors at Shinkolbwe, Zaire, a uraninite-bearing ore body exposed to highly oxidizing conditions at the surface, provides over 50 species of uranyl phases for detailed study, and illustrates a complex uranyl phase paragenesis over several million years, from earliest-formed uranyl oxide hydrates and uranyl silicates to later-formed uranyl phosphate. (au) (268 refs.)

  14. The role of colloids and suspended particles in radionuclide transport in the Canadian concept for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Vilks, P.

    1994-02-01

    AECL Research is developing a concept for the permanent disposal of nuclear fuel waste in a deep engineered vault in plutonic rock of the Canadian Shield and is preparing an Environmental Impact Statement (EIS) to document its case for the acceptability of the disposal concept. This report, one in a series of supporting documents for the EIS, addresses the role of particles in radionuclide transport. It summarizes our studies of natural particles in groundwater and presents the arguments used to justify the omission of particle-facilitated transport in the geosphere model that is based on the Whiteshell Research Area (WRA) and used in the postclosure assessment study case. Because radiocolloids formed in the vault will not be able to migrate through the clay buffer, radiocolloid formation in the geosphere will be determined by the sorption of radionuclides onto particles in groundwater. These particles consist of typical fracture-lining minerals, such as clays, micas and quartz; precipitated particles, such as colloidal silica and Fe-Si oxyhydroxides; and organic particles. In groundwater from the WRA, the average concentrations of colloids and suspended particles are 0.34 and 1.4 mg/L respectively. Particle-facilitated transport is not included in the geosphere model because the concentrations of particles in groundwater from the WRA are too low to have a significant impact on radionuclide transport. (author). 92 refs., 11 tabs., 13 figs

  15. Alternative Concept to Enhance the Disposal Efficiency for CANDU Spent Fuel Disposal System

    International Nuclear Information System (INIS)

    Lee, Jong Youl; Cho, Dong Geun; Kook, Dong Hak; Lee, Min Soo; Choi, Heui Joo

    2011-01-01

    There are two types of nuclear reactors in Korea and they are PWR type and CANDU type. The safe management of the spent fuels from these reactors is very important factor to maintain the sustainable energy supply with nuclear power plant. In Korea, a reference disposal system for the spent fuels has been developed through a study on the direct disposal of the PWR and CANDU spent fuel. Recently, the research on the demonstration and the efficiency analyses of the disposal system has been performed to make the disposal system safer and more economic. PWR spent fuels which include a lot of reusable material can be considered being recycled and a study on the disposal of HLW from this recycling process is being performed. CANDU spent fuels are considered being disposed of directly in deep geological formation, since they have little reusable material. In this study, based on the Korean Reference spent fuel disposal System (KRS) which was to dispose of both PWR type and CANDU type, the more effective CANDU spent fuel disposal systems were developed. To do this, the disposal canister for CANDU spent fuels was modified to hold the storage basket for 60 bundles which is used in nuclear power plant. With these modified disposal canister concepts, the disposal concepts to meet the thermal requirement that the temperature of the buffer materials should not be over 100 .deg. C were developed. These disposal concepts were reviewed and analyzed in terms of disposal effective factors which were thermal effectiveness, U-density, disposal area, excavation volume, material volume etc. and the most effective concept was proposed. The results of this study will be used in the development of various wastes disposal system together with the HLW wastes from the PWR spent fuel recycling process.

  16. Nuclear waste disposal

    International Nuclear Information System (INIS)

    Schueller, W.

    1976-01-01

    The article cites and summarizes the papers on the topics: economic and ecological importance of waste management, reprocessing of nuclear fuel and recycling of uranium and plutonium, waste management and final storage, transports and organizational aspects of waste management, presented at this symposium. (HR/AK) [de

  17. Whither nuclear waste disposal?

    International Nuclear Information System (INIS)

    Cotton, T.A.

    1990-01-01

    With respect to the argument that geologic disposal has failed, I do not believe that the evidence is yet sufficient to support that conclusion. It is certainly true that the repository program is not progressing as hoped when the Nuclear Waste Policy Act of 1982 established a 1998 deadline for initial operation of the first repository. The Department of Energy (DOE) now expects the repository to be available by 2010, and tat date depends upon a finding that the Yucca Mountain site - the only site that DOE is allowed by law to evaluate - is in fact suitable for use. Furthermore, scientific evaluation of the site to determine its suitability is stopped pending resolution of two lawsuits. However, I believe it is premature to conclude that the legal obstacles are insuperable, since DOE just won the first of the two lawsuits, and chances are good it will win the second. The concept of geologic disposal is still broadly supported. A recent report by the Board on Radioactive Waste Management of the National Research Council noted that 'There is a worldwide scientific consensus that deep geological disposal, the approach being followed in the United States, is the best option for disposing of high-level radioactive waste'. The U.S. Nuclear Regulatory Commission (USNRC) recently implicitly endorsed this view in adopting an updated Waste Confidence position that found confidence that a repository could be available in the first quarter of the next century - sufficient time to allow for rejection of Yucca Mountain and evaluation of a new site

  18. Whither nuclear waste disposal?

    Energy Technology Data Exchange (ETDEWEB)

    Cotton, T A [JK Research Associates, Silver Spring, MD (United States)

    1990-07-01

    With respect to the argument that geologic disposal has failed, I do not believe that the evidence is yet sufficient to support that conclusion. It is certainly true that the repository program is not progressing as hoped when the Nuclear Waste Policy Act of 1982 established a 1998 deadline for initial operation of the first repository. The Department of Energy (DOE) now expects the repository to be available by 2010, and tat date depends upon a finding that the Yucca Mountain site - the only site that DOE is allowed by law to evaluate - is in fact suitable for use. Furthermore, scientific evaluation of the site to determine its suitability is stopped pending resolution of two lawsuits. However, I believe it is premature to conclude that the legal obstacles are insuperable, since DOE just won the first of the two lawsuits, and chances are good it will win the second. The concept of geologic disposal is still broadly supported. A recent report by the Board on Radioactive Waste Management of the National Research Council noted that 'There is a worldwide scientific consensus that deep geological disposal, the approach being followed in the United States, is the best option for disposing of high-level radioactive waste'. The U.S. Nuclear Regulatory Commission (USNRC) recently implicitly endorsed this view in adopting an updated Waste Confidence position that found confidence that a repository could be available in the first quarter of the next century - sufficient time to allow for rejection of Yucca Mountain and evaluation of a new site.

  19. Final disposal of spent nuclear fuel in Sweden. Some unresolved issues and challenges in the design and implementation of the forthcoming planning and EIA processes

    International Nuclear Information System (INIS)

    Bjarnadottir, H.; Hilding-Rydevik, T.

    2001-06-01

    The aim of the study is to highlight some unresolved and challenging issues in the forthcoming approximately six year long Environmental Impact Assessment (EIA) and planning process of the long-term disposal of spent nuclear fuel in Sweden. Different international and Nordic experiences of the processes for final disposal as well as from other development of similar scope, where experiences assumed to be of importance for final disposal of nuclear waste, have been described. Furthermore, issues relating to 'good EIA practice' as well as certain aspects of planning theory have also been presented. The current Swedish situation for the planning and EIA process of the final disposal of spent nuclear fuel was also been summarized. These different 'knowledge areas' have been compared and measured against our perception of the expectations towards the forthcoming process, put forward by different Swedish actors in the field. The result is a presentation of a number of questions and identification issues that the authors consider need special attention in the design and conduction of the planning and EIA process. The study has been realized through a literature survey and followed by reading and analysis of the written material. The main focus of the literature search was on material describing planning processes, actor perspectives and EIA. Material and literature on the technical and scientific aspects of spent nuclear fuel disposal was however deliberately avoided. There is a wealth of international and Swedish literature concerning final disposal of spent nuclear fuel - concerning both technical issues and issues concerning for example public participation and risk perception. But material of a more systematic and comparative nature (relating to both empirical and theoretical issues, and to practical experiences) in relation to EIA processes and communicative planning for final disposal of spent nuclear fuel seems to be more sparsely represented. Our perception of

  20. Nuclear fuels

    International Nuclear Information System (INIS)

    2008-01-01

    The nuclear fuel is one of the key component of a nuclear reactor. Inside it, the fission reactions of heavy atoms, uranium and plutonium, take place. It is located in the core of the reactor, but also in the core of the whole nuclear system. Its design and properties influence the behaviour, the efficiency and the safety of the reactor. Even if it represents a weak share of the generated electricity cost, its proper use represents an important economic stake. Important improvements remain to be made to increase its residence time inside the reactor, to supply more energy, and to improve its robustness. Beyond the economical and safety considerations, strategical questions have to find an answer, like the use of plutonium, the management of resources and the management of nuclear wastes and real technological challenges have to be taken up. This monograph summarizes the existing knowledge about the nuclear fuel, its behaviour inside the reactor, its limits of use, and its R and D tracks. It illustrates also the researches in progress and presents some key results obtained recently. Content: 1 - Introduction; 2 - The fuel of water-cooled reactors: aspect, fabrication, behaviour of UO 2 and MOX fuels inside the reactor, behaviour in loss of tightness situation, microscopic morphology of fuel ceramics and evolution under irradiation - migration and localisation of fission products in UOX and MOX matrices, modeling of fuels behaviour - modeling of defects and fission products in the UO 2 ceramics by ab initio calculations, cladding and assembly materials, pellet-cladding interaction, advanced UO 2 and MOX ceramics, mechanical behaviour of the fuel assembly, fuel during a loss of coolant accident, fuel during a reactivity accident, fuel during a serious accident, fuel management inside reactor cores, fuel cycle materials balance, long-term behaviour of the spent fuel, fuel of boiling water reactors; 3 - the fuel of liquid metal fast reactors: fast neutrons radiation

  1. Consultation Report. Consultation under the Environmental Act sixth chapter 4 paragraph for interim storage, encapsulation and disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    2010-09-01

    This consultation report is an appendix to the Environmental Impact Assessment (EIA) which in turn is an appendix to SKB's application under the Environmental Code for the continued operation of CLAB (Central interim storage for spent Nuclear Fuel, located on the Simpevarp Peninsula in Oskarshamn municipality), to build the encapsulation plant and operate it integrated with CLAB and to construct and operate the disposal facility in Soederviken at Forsmark in Oesthammar municipality, and SKB's application for a license under the Nuclear Activities Act to construct and operate the disposal facility at Forsmark. The aim of the consultation report is to give an overall picture of the consultations

  2. Introduction of microbial nutrients in a nuclear fuel waste disposal vault as a result of excavation and operation activities

    International Nuclear Information System (INIS)

    Stroes-Gascoyne, S.; Gascoyne, M.; Onagi, D.; Thomas, D.A.; Hamon, C.J.; Watson, R.; Porth, R.J.

    1996-08-01

    A nuclear fuel waste disposal vault would not likely be a sterile environment. Bacterial activity would be expected in those areas of the vault conducive to bacterial life, i.e., where effects of heat, moisture content, radiation and compaction would not prevent or severely restrict bacterial life and where suitable and sufficient nutrients would be present. An inventory of bacterial nutrients that would be emplaced 'intentionally' with vault materials (fuel waste, waste containers, buffer and backfill materials) has been made previously. This report assesses bacterial nutrients that would be added 'inadvertently' to a vault in the form of residues of materials used to excavate and operate a vault. Measurements of blasting material residues in the various water supplies, excavated broken rock (muck) and in cores drilled in old and new tunnel walls were made at AECL's Underground Research Laboratory. Results show that the largest potential nutrient addition (both carbon and nitrogen) to a vault would result from using untreated excavated broken rock as part of the backfill. (author). 16 refs., 4 tabs., 10 figs

  3. Introduction of microbial nutrients in a nuclear fuel waste disposal vault as a result of excavation and operation activities

    Energy Technology Data Exchange (ETDEWEB)

    Stroes-Gascoyne, S; Gascoyne, M; Onagi, D; Thomas, D A; Hamon, C J; Watson, R; Porth, R J

    1996-08-01

    A nuclear fuel waste disposal vault would not likely be a sterile environment. Bacterial activity would be expected in those areas of the vault conducive to bacterial life, i.e., where effects of heat, moisture content, radiation and compaction would not prevent or severely restrict bacterial life and where suitable and sufficient nutrients would be present. An inventory of bacterial nutrients that would be emplaced `intentionally` with vault materials (fuel waste, waste containers, buffer and backfill materials) has been made previously. This report assesses bacterial nutrients that would be added `inadvertently` to a vault in the form of residues of materials used to excavate and operate a vault. Measurements of blasting material residues in the various water supplies, excavated broken rock (muck) and in cores drilled in old and new tunnel walls were made at AECL`s Underground Research Laboratory. Results show that the largest potential nutrient addition (both carbon and nitrogen) to a vault would result from using untreated excavated broken rock as part of the backfill. (author). 16 refs., 4 tabs., 10 figs.

  4. Nuclear fuel element

    International Nuclear Information System (INIS)

    Grossman, L.N.; Levin, H.A.

    1975-01-01

    A nuclear fuel element has disposed therein an alloy having the essential components of nickel, titanium and zirconium, and the alloy reacts with water, water vapor and reactive gases at reactor ambient temperatures. The alloy is disposed in the plenum of the fuel element in the form of particles in a hollow gas permeable container having a multiplicity of openings of size smallr than the size of the particles. The container is preferably held in the spring in the plenum of the fuel element. (E.C.B.)

  5. Interfaces between transport and geological disposal systems for high level radioactive waste and spent nuclear fuel

    International Nuclear Information System (INIS)

    1994-09-01

    This document is an IAEA publication which identifies and discusses the interfaces and the interface requirements between high level waste, the waste transport system used for carriage of the waste to the disposal facility, and the high level waste disposal facility. The development of this document was prompted in part by the initiatives in various Member States to select, characterize and design the facilities for potential high level waste geological repositories. These initiatives have progressed to the point where an international document would be useful in calling attention to the need for establishing, in a systematic way, interfaces and interface requirements between the transport systems to be used and the waste disposal packages and geological repository. Refs, figs and tabs

  6. Nuclear fuel

    International Nuclear Information System (INIS)

    Azevedo, J.B.L. de.

    1980-01-01

    All stages of nuclear fuel cycle are analysed with respect to the present situation and future perspectives of supply and demand of services; the prices and the unitary cost estimation of these stages for the international fuel market are also mentioned. From the world resources and projections of uranium consumption, medium-and long term analyses are made of fuel availability for several strategies of use of different reactor types. Finally, the cost of nuclear fuel in the generation of electric energy is calculated to be used in the energetic planning of the electric sector. (M.A.) [pt

  7. Nonlinear chemical sorption isotherms in the assessment of nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Walker, J.R.; LeNeveu, D.M.

    1987-01-01

    Radionuclides emplaced in an underground disposal vault can possibly migrate from the vault, and through the geosphere, to enter Man's environment. Chemical sorption is a primary mechanism for retarding this migration. The effects of nonlinear chemical sorption isotherms on radionuclide transport are discussed. A method is given by which nonlinear isotherms can be approximated by the linear sorption isotherm used in the vault submodel. The relevance of nonlinear isotherms to transport in the geosphere is discussed, and it is shown that the linear isotherm model is conservative for deep geologic disposal. 22 refs

  8. The spent fuel disposal program in Taiwan

    International Nuclear Information System (INIS)

    Li, K.K.

    1994-01-01

    It is important, especially for countries with plan to develop nuclear power, to recognize that two key factors to the future prosperity of nuclear power are the safety of nuclear power plants and the appropriate management of backend activities. This paper described the financial, managerial, technical, and political status of the spent fuel disposal program in a newly industrialized country. It is concluded that the R ampersand D works and operational practices associated with the backend activities must be carried out in parallel with the development of nuclear power

  9. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Rechard, R.P.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste, as mandated by the Nuclear Waste Policy Act of 1982. The waste forms comprised about 700 metric tons of initial heavy metal (or equivalent units) stored at the INEL: graphite spent fuel, experimental low enriched and highly enriched spent fuel, and high-level waste generated during reprocessing of some spent fuel. Five different waste treatment options were studied; in the analysis, the options and resulting waste forms were analyzed separately and in combination as five waste disposal groups. When the waste forms were studied in combination, the repository was assumed to also contain vitrified high-level waste from three DOE sites for a common basis of comparison and to simulate the impact of the INEL waste forms on a moderate-sized repository, The performance of the waste form was assessed within the context of a whole disposal system, using the U.S. Environmental Protection Agency's Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191, promulgated in 1985. Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories

  10. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory. Volume 2: Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [ed.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste, as mandated by the Nuclear Waste Policy Act of 1982. The waste forms comprised about 700 metric tons of initial heavy metal (or equivalent units) stored at the INEL: graphite spent fuel, experimental low enriched and highly enriched spent fuel, and high-level waste generated during reprocessing of some spent fuel. Five different waste treatment options were studied; in the analysis, the options and resulting waste forms were analyzed separately and in combination as five waste disposal groups. When the waste forms were studied in combination, the repository was assumed to also contain vitrified high-level waste from three DOE sites for a common basis of comparison and to simulate the impact of the INEL waste forms on a moderate-sized repository, The performance of the waste form was assessed within the context of a whole disposal system, using the U.S. Environmental Protection Agency`s Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191, promulgated in 1985. Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories.

  11. Consideration of Nuclear Criticality When Directly Disposing Highly Enriched Spent Nuclear Fuel in Unsaturated Tuff - I: Nuclear Criticality Constraints

    International Nuclear Information System (INIS)

    Rechard, Rob P.; Sanchez, Lawrence C.; Trellue, Holly R.

    2003-01-01

    This paper presents the mass, concentration, and volume required for a critical event to occur in homogeneous mixtures of fissile material and various other geologic materials. The fissile material considered is primarily highly enriched uranium spent fuel; however, 239 Pu is considered in some cases. The non-fissile materials examined are those found in the proposed repository area at Yucca Mountain, Nevada: volcanic tuff, iron rust, concrete, and naturally occurring water. For 235 U, the minimum critical solid concentration for tuff was 5 kg/m 3 (similar to sandstone), and in goethite, 45 kg/m 3 . The critical mass of uranium was sensitive to a number of factors, such as moisture content and fissile enrichment, but had a minimum, assuming almost 100% saturation and >20% enrichment, of 18 kg in tuff as Soddyite (or 9.5 kg as UO 2 ) and 7 kg in goethite. For 239 Pu, the minimum critical solid concentration for tuff was 3 kg/m 3 (similar to sandstone); in goethite, 20 kg/m 3 . The critical mass of plutonium was also sensitive to a number of factors, but had a minimum, assuming 100% saturation and 80-90% enrichment, of 5 kg in tuff and 6 kg in goethite

  12. Improved nuclear fuel element

    International Nuclear Information System (INIS)

    1974-01-01

    A nuclear fuel element for use in the core of a nuclear reactor is disclosed and has a metal liner disposed between the cladding and the nuclear fuel material and a high lubricity material in the form of a coating disposed between the liner and the cladding. The liner preferably has a thickness greater than the longest fission product recoil distance and is composed of a low neutron capture cross-section material. The liner is preferably composed of zirconium, an alloy of zirconium, niobium or an alloy of niobium. The liner serves as a preferential reaction site for volatile impurities and fission products and protects the cladding from contact and reaction with such impurities and fission products. The high lubricity material acts as an interface between the liner and the cladding and reduces localized stresses on the cladding due to fuel expansion and cracking of the fuel

  13. Program for responsible and safe disposal of spent fuel elements and radioactive wastes (National disposal program)

    International Nuclear Information System (INIS)

    2015-01-01

    The contribution covers the following topics: fundamentals of the disposal policy; amount of radioactive wastes and prognosis; disposal of radioactive wastes - spent fuel elements and wastes from waste processing, radioactive wastes with low heat production; legal framework of the nuclear waste disposal in Germany; public participation, cost and financing.

  14. The Swedish Radiation Protection Institute's protection criteria for disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    1995-12-01

    In this document the Swedish Radiation Protection Institute reports the preliminary protection criteria for personnel and public concerned with, or in other ways affected by, the disposal of high level radioactive waste. The document will be submitted for consideration by the parties concerned and also serve as a basis for preparing a Swedish viewpoint which can be asserted in future international discussions

  15. The Swedish Radiation Protection Institute`s protection criteria for disposal of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    In this document the Swedish Radiation Protection Institute reports the preliminary protection criteria for personnel and public concerned with, or in other ways affected by, the disposal of high level radioactive waste. The document will be submitted for consideration by the parties concerned and also serve as a basis for preparing a Swedish viewpoint which can be asserted in future international discussions.

  16. Thermal and mechanical analyses of the spent nuclear fuel disposal canister and its barriers according to the design variable change

    International Nuclear Information System (INIS)

    Kwon, Young Joo

    2006-03-01

    This work constitutes a summary of research and development made for design and dimensioning of the spent nuclear fuel disposal canister. Since the spent nuclear fuel disposal emits high temperature heats and much radiation, its careful treatment is required. For that, a long term (usually 10,000 years) safe repository for the spent nuclear fuel disposal should be secured. Usually this repository is expected to locate at a depth of 500m underground. Many various analyses should be performed to secure the structural safety of the canister. For past years, these analyses have been performed to develop the canister model (so-called DKC-1 model). The diameter of the designed KDC-1 canister model is D=102m. However, there still remain some structural evaluations to make sure the structural safety of the designed KDC-1 canister mode. The one is the structural safety evaluation of the canister for the falling accident in the repository while handling the canister. There may happen two typical falling accidents in the repository. The one is the falling accident of the canister in the borehole while depositing the canister into the borehole. In these falling accidents the collision impact force between the canister and the surface of the ground or the bottom of the borehole may cause the structural damage onto the canister. However, the canister should be designed to withstand this impact force. Hence, the structural analysis of the canister for this impact force is required to guarantee the structural safety of the canister for this falling accident. Therefore in this report, the structural analyses of the KDC-1 canister model of the diameter of 102cm for two types of falling accidents are carried out for the impact forces while the canister collides onto the surface of the ground or the bottom of the borehole. The nonlinear structural analyses are performed for the canister to get the accurate analysis results assuming the materials composing canister parts as elasto

  17. Final disposal of spent nuclear fuel in Sweden: The evolving role for KASAM when society is preparing for important decisions

    International Nuclear Information System (INIS)

    Glimelius, Kristina; Hedberg, Bjoern; Norrby, Soeren; Soederberg, Olof

    2006-01-01

    KASAM, the Swedish National Council for Nuclear Waste, is an independent scientific council attached to the Ministry of Sustainable Development. The members of KASAM are independent scientists within a wide range of areas of importance for the final disposal of radioactive waste, not only within technology and natural sciences but also within areas such as ethics and social sciences. Swedish nuclear waste management policy and implementation is currently in a protracted phase of planning and decisions. Starting in 2006 , the Swedish Nuclear Waste Management Co (SKB) is expected to submit the necessary applications for permits to construct an encapsulation facility and a disposal facility for spent nuclear fuel (in crystalline bedrock about 500 meters below the ground). According to Swedish legislation, basic permits have to be granted by the Government, but the Government will not grant such permits unless the concerned host municipality accepts the proposal. The Government decision will form the basis for detailed licensing decisions by the regulatory authorities. KASAM has an important role as an independent advisory body to the Ministry of Sustainable Development. Also, KASAM will continue its function of creating forums for dialogue that could contribute to increase knowledge and understanding and improve the knowledge base for decision-making. There are a number of questions that are relevant. Examples are: Will society have a satisfactory basis for decision-making? What happens if society is not capable of making necessary decisions? Does the decision-making process enable society to postpone important decisions if more time is needed, to avoid obstacles if they appear, and - if needed - reverse decisions? Considering issues like this, KASAM has set up a plan for its activities in the next few years. These activities are meant to contribute to the ability of society as a whole to arrive at a well-founded decision that is widely accepted. Based on facts

  18. Overview of nuclear waste disposal in space

    International Nuclear Information System (INIS)

    Rice, E.E.; Priest, C.C.

    1981-01-01

    One option receiving consideration by the Department of Energy (DOE) is the space disposal of certain high-level nuclear wastes. The National Aeronautics and Space Administration is assessing the space disposal option in support of DOE studies on alternatives for nuclear waste management. The space disposal option is viewed as a complement, since total disposal of fuel rods from commercial power plants is not considered to be economically practical with Space Shuttle technology. The space disposal of certain high-level wastes may, however, provide reduced calculated and perceived risks. The space disposal option in conjunction with terrestrial disposal may offer a more flexible and lower risk overall waste management system. For the space disposal option to be viable, it must be demonstrated that the overall long-term risks associated with this activity, as a complement to the mined geologic repository, would be significantly less than the long-term risk associated with disposing of all the high-level waste. The long-term risk benefit must be achieved within an acceptable short-term and overall program cost. This paper briefly describes space disposal alternatives, the space disposal destination, possible waste mixes and forms, systems and typical operations, and the energy and cost analysis

  19. Geological disposal of nuclear waste

    International Nuclear Information System (INIS)

    1979-01-01

    Fourteen papers dealing with disposal of high-level radioactive wastes are presented. These cover disposal in salt deposits, geologic deposits and marine disposal. Also included are papers on nuclear waste characterization, transport, waste processing technology, and safety analysis. All of these papers have been abstracted and indexed

  20. Nuclear reactor fuel element splitter

    International Nuclear Information System (INIS)

    Yeo, D.

    1976-01-01

    A method and apparatus are disclosed for removing nuclear fuel from a clad fuel element. The fuel element is power driven past laser beams which simultaneously cut the cladding lengthwise into at least two longitudinal pieces. The axially cut lengths of cladding are then separated, causing the nuclear fuel contained therein to drop into a receptacle for later disposition. The cut lengths of cladding comprise nuclear waste which is disposed of in a suitable manner. 6 claims, 10 drawing figures

  1. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Formulation of radionuclide release scenarios 2012

    International Nuclear Information System (INIS)

    2013-04-01

    TURVA-2012 is Posiva's safety case in support of the Preliminary Safety Analysis Report (PSAR) and application for a construction licence for a repository for disposal of spent nuclear fuel at the Olkiluoto site in south-western Finland. This report presents the radionuclide release scenarios and the methodology followed in formulating them. The formulation of scenarios takes into account the regulatory framework, the knowledge acquired in the present safety case as well as in previous safety assessments, the safety functions of the barriers of the repository system and the uncertainties in the features, events, and processes (FEPs) that may affect the entire disposal system (i.e. repository system plus the surface environment) from the emplacement of the first canister until the far future. In the report Performance Assessment, the performance of the engineered and natural barriers has been assessed against the loads expected during the evolution of the repository system and the site. Uncertainties have been identified and these are taken into account in the formulation of radionuclide release scenarios. The uncertainties in the FEPs affecting the characteristics and evolution of the surface environment are taken into account in formulating the surface environment scenarios used ultimately for assessing radiation exposure. Formulating radionuclide release scenarios for the repository system links the reports Performance Assessment and Assessment of Radionuclide Release Scenarios for the Repository System. The formulation of radionuclide release scenarios for the surface environment brings together Biosphere Description and the surface environment FEPs and is the link to the assessment of the surface environment scenarios analysed in Biosphere Assessment. (orig.)

  2. Review of geoscientific data of relevance to disposal of spent nuclear fuel in deep boreholes in crystalline rock

    International Nuclear Information System (INIS)

    Marsic, Nico; Grundfelt, Bertil

    2013-09-01

    In this report a compilation of recent geoscientific data of relevance to disposal of spent nuclear fuel in deep boreholes in Sweden is presented. The goal of the study has been limited to identifying and briefly describing such geoscientific information of relevance to disposal in deep boreholes that was not available at the time when previous compilations were made. Hence, the study is not to be regarded as a general up-date of new geoscientific information. Disposal of spent nuclear fuel in deep boreholes has been studied in Sweden since the second half of the 1980s. The currently studied concept has been proposed by Sandia National Laboratories in the USA. In this concept the spent fuel elements are encapsulated in cylindrical steel canisters that are joined together in strings of 40 canisters and lowered into five kilometres deep boreholes. Ten such strings are stacked between three and five kilometres depth separated from each other by concrete plugs. The study started with a review of boreholes that have been reported after the previous reviews that were published in 1998 and 2004. A total of 12 boreholes of potential relevance were identified. Further study showed that only four out of these holes penetrated into crystalline rock. Two of these were deemed to be less relevant because they were drilled in areas with much higher geothermal gradient than in the parts of the Fennoscandian shield that realistically could host a Swedish deep borehole repository. Of the two remaining boreholes, only one, a geoscientific hole drilled at Outokumpu in Finland, is associated with a reasonably complete geoscientific data set. It is worth mentioning that a large part of this hole is drilled through meta sedimentary rock (mica schist) rather than granitic rock. The information collected and reviewed has been gathered under the headings hydraulic conditions, geothermal conditions, hydrogeochemical conditions, bacteriological activity and rock mechanical properties. Only

  3. Review of geoscientific data of relevance to disposal of spent nuclear fuel in deep boreholes in crystalline rock

    Energy Technology Data Exchange (ETDEWEB)

    Marsic, Nico; Grundfelt, Bertil [Kemakta Konsult AB, Stockholm (Sweden)

    2013-09-15

    In this report a compilation of recent geoscientific data of relevance to disposal of spent nuclear fuel in deep boreholes in Sweden is presented. The goal of the study has been limited to identifying and briefly describing such geoscientific information of relevance to disposal in deep boreholes that was not available at the time when previous compilations were made. Hence, the study is not to be regarded as a general up-date of new geoscientific information. Disposal of spent nuclear fuel in deep boreholes has been studied in Sweden since the second half of the 1980s. The currently studied concept has been proposed by Sandia National Laboratories in the USA. In this concept the spent fuel elements are encapsulated in cylindrical steel canisters that are joined together in strings of 40 canisters and lowered into five kilometres deep boreholes. Ten such strings are stacked between three and five kilometres depth separated from each other by concrete plugs. The study started with a review of boreholes that have been reported after the previous reviews that were published in 1998 and 2004. A total of 12 boreholes of potential relevance were identified. Further study showed that only four out of these holes penetrated into crystalline rock. Two of these were deemed to be less relevant because they were drilled in areas with much higher geothermal gradient than in the parts of the Fennoscandian shield that realistically could host a Swedish deep borehole repository. Of the two remaining boreholes, only one, a geoscientific hole drilled at Outokumpu in Finland, is associated with a reasonably complete geoscientific data set. It is worth mentioning that a large part of this hole is drilled through meta sedimentary rock (mica schist) rather than granitic rock. The information collected and reviewed has been gathered under the headings hydraulic conditions, geothermal conditions, hydrogeochemical conditions, bacteriological activity and rock mechanical properties. Only

  4. Interfaces between transport and geologic disposal systems for high-level radioactive wastes and spent nuclear fuel: A new international guidance document

    International Nuclear Information System (INIS)

    Pope, R.B.; Baekelandt, L.; Hoorelbeke, J.M.; Han, K.W.; Pollog, T.; Blackman, D.; Villagran, J.E.

    1994-01-01

    An International Atomic Energy Agency (IAEA) Technical Document (TECDOC) has been developed and will be published by the IAEA. The TECDOC addresses the interfaces between the transport and geologic disposal systems for, high-level waste (HLW) and spent nuclear fuel (SNF). The document is intended to define and assist in discussing, at both the domestic and the international level, regulatory, technical, administrative, and institutional interfaces associated with HLW and SNF transport and disposal systems; it identifies and discusses the interfaces and interface requirements between the HLW and SNF, the waste transport system used for carriage of the waste to the disposal facility, and the HLW/SNF disposal facility. It provides definitions and explanations of terms; discusses systems, interfaces and interface requirements; addresses alternative strategies (single-purpose packages and multipurpose packages) and how interfaces are affected by the strategies; and provides a tabular summary of the requirements

  5. Nuclear fuel reprocessing and high level waste disposal: informational hearings. Volume XII. Public and private roles, Part 2

    International Nuclear Information System (INIS)

    1977-01-01

    Presentations were made on institutional experiences at Nuclear Fuel Services, the framework for an acceptable nuclear future, the Price-Anderson Indemnity Act, Congress and nuclear energy policy, human dimension, and risk perception. The supplemental testimony and materials submitted for the record included information of the nuclear waste at West Valley, New York, the perception and acceptability of risk from nuclear and alternative energy sources, and psychological determinants of perceived and acceptable risk

  6. The psychosocial consequences of spent fuel disposal

    International Nuclear Information System (INIS)

    Paavola, J.; Eraenen, L.

    1999-03-01

    In this report the potential psychosocial consequences of spent fuel disposal to inhabitants of a community are assessed on the basis of earlier research. In studying the situation, different interpretations and meanings given to nuclear power are considered. First, spent fuel disposal is studied as fear-arousing and consequently stressful situation. Psychosomatic effects of stress and coping strategies used by an individual are presented. Stress as a collective phenomenon and coping mechanisms available for a community are also assessed. Stress reactions caused by natural disasters and technological disasters are compared. Consequences of nuclear power plant accidents are reviewed, e.g. research done on the accident at Three Mile Island power plant. Reasons for the disorganising effect on a community caused by a technological disaster are compared to the altruistic community often seen after natural disasters. The potential reactions that a spent fuel disposal plant can arouse in inhabitants are evaluated. Both short-term and long-term reactions are evaluated as well as reactions under normal functioning, after an incident and as a consequence of an accident. Finally an evaluation of how the decision-making system and citizens' opportunity to influence the decision-making affect the experience of threat is expressed. As a conclusion we see that spent fuel disposal can arouse fear and stress in people. However, the level of the stress is probably low. The stress is at strongest at the time of the starting of the spent fuel disposal plant. With time people get used to the presence of the plant and the threat experienced gets smaller. (orig.)

  7. A geographic information system and multi criteria analysis method for site selection of spent nuclear fuel disposal

    International Nuclear Information System (INIS)

    Martins, Vivian Borges

    2009-01-01

    This thesis aims to develop a site selection methodology for the construction of final repository for the spent nuclear fuel disposal, by using geographic information systems (GIS) and multi-criteria decision analysis. Decision making processes of this kind are often complex, given the great number of space parameters to consider and also the typically conflicting opinions of the diverse stake holders. By using GIS, data from different space parameters can be quickly and reliably stored, treated and analyzed. Multi-criteria techniques allow for the incorporation of different stake holders' opinions. These tools, when jointly used, allow for the decision process to be more transparent, quick and reliable. The method developed was applied to the particular case of the state of Rio de Janeiro. Weights obtained from an expert panel and also by using the Hierarchical Analysis Method and cartographic data were combined in the GIS. The application showed that it is possible not only to select and classify areas as to their aptness for the proposed objective, but also to exclude those clearly inadequate areas, thus optimizing the selection process by reducing the search space and consequently minimizing costs and the time spent in the search. (author)

  8. Seismic VSP and HSP surveys on preliminary investigation areas in Finland for final disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Keskinen, J.; Cosma, C.; Heikkinen, P.

    1992-10-01

    Seismic reflection surveys in boreholes were carried out for Teollisuuden Voima Oy at five sites in Finland (Eurajoki Olkiluoto, Hyrynsalmi Veitsivaara, Konginkangas Kivetty, Kuhmo Romuvaara and Sievi Syyry). The vertical Seismic Profiling (VSP) surveys were a part of the investigation programme for the final disposal of spent nuclear fuel. The purpose was to detect fractured zones, lithological contacts and other anomalies in the structure of the rockmass and to determine their position and orientation. Horizontal Seismic Profiling (HSP) was used at the Olkiluoto site, additionally to VSP. The data has been organized in profiles containing seismograms recorded from the same shotpoint (shot gathers). One of the most powerful processing methods used with this project has been the Image Space Filtering, a new technique, which has been developed (in the project) for seismic reflection studies in crystalline rock. The method can be applied with other rock types where steeply inclined or vertical anomalies are of interest. It acts like a multichannel filter, enhancing the reflected events and also as an interpretation tool, to estimate the strength and position of the reflectors. This approach has been of great help in emphasizing the weak reflections from uneven and sometimes vanishing interfaces encountered in crystalline

  9. Nuclear waste disposal in space

    Science.gov (United States)

    Burns, R. E.; Causey, W. E.; Galloway, W. E.; Nelson, R. W.

    1978-01-01

    Work on nuclear waste disposal in space conducted by the George C. Marshall Space Flight Center, National Aeronautics and Space Administration, and contractors are reported. From the aggregate studies, it is concluded that space disposal of nuclear waste is technically feasible.

  10. 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

  11. Review of the nuclear waste disposal problem

    International Nuclear Information System (INIS)

    Poch, L.A.; Wolsko, T.D.

    1979-10-01

    Regardless of future nuclear policy, a nuclear waste disposal problem does exist and must be dealt with. Even a moratorium on new nuclear plants leaves us with the wastes already in existence and wastes yet to be generated by reactors in operation. Thus, technologies to effectively dispose of our current waste problem must be researched and identified and, then, disposal facilities built. The magnitude of the waste disposal problem is a function of future nuclear policy. There are some waste disposal technologies that are suitable for both forms of HLW (spent fuel and reprocessing wastes), whereas others can be used with only reprocessed wastes. Therefore, the sooner a decision on the future of nuclear power is made the more accurately the magnitude of the waste problem will be known, thereby identifying those technologies that deserve more attention and funding. It is shown that there are risks associated with every disposal technology. One technology may afford a higher isolation potential at the expense of increased transportation risks in comparison to a second technology. Establishing the types of risks we are willing to live with must be resolved before any waste disposal technology can be instituted for widespread commercial use

  12. The feasibility of modelling coupled processes in safety analysis of spent nuclear fuel disposal

    Energy Technology Data Exchange (ETDEWEB)

    Rasilainen, K. [VTT Energy, Espoo (Finland); Luukkonen, A.; Niemi, A.; Poellae, J. [VTT Communities and Infrastructure, Espoo (Finland); Olin, M. [VTT Chemical Technology, Espoo (Finland)

    1999-07-01

    The potential of applying coupled modelling in the Finnish safety analysis programme has been reviewed. The study focused on the migration of radionuclides escaping from a spent fuel repository planned to be excavated in fractured bedrock. Two effects that can trigger various couplings in and around a spent fuel repository in Finland were studied in detail; namely heat generation in the spent fuel and the presence of deep, saline groundwaters. The latter have been observed in coastal areas. A systematic survey of the requirements of coupled modelling identified features that render such migration calculations a challenging task. In groundwater flow modelling there appears to be wide ranging uncertainty related to conceptualisation of flow systems and to the corresponding input data. In terms of migration related chemistry there appear to be large gaps in the underlying thermodynamic database for geochemical systems. Rock mechanical predictions are heavily dependent on knowing the location, structure and properties of dominant fractures; information which is extremely difficult to obtain. Conduction and convection of heat is understood well in principle. On the basis of this review, it appears that coupled migration modelling may not yet be at the stage of development that would allow its use as a standard modelling tool in performance assessments. However, a firmer basis for the conclusions reached can only be obtained after a systematic modelling exercise on a relevant and real migration problem has been carried out. (orig.)

  13. The feasibility of modelling coupled processes in safety analysis of spent nuclear fuel disposal

    International Nuclear Information System (INIS)

    Rasilainen, K.; Luukkonen, A.; Niemi, A.; Poellae, J.; Olin, M.

    1999-01-01

    The potential of applying coupled modelling in the Finnish safety analysis programme has been reviewed. The study focused on the migration of radionuclides escaping from a spent fuel repository planned to be excavated in fractured bedrock. Two effects that can trigger various couplings in and around a spent fuel repository in Finland were studied in detail; namely heat generation in the spent fuel and the presence of deep, saline groundwaters. The latter have been observed in coastal areas. A systematic survey of the requirements of coupled modelling identified features that render such migration calculations a challenging task. In groundwater flow modelling there appears to be wide ranging uncertainty related to conceptualisation of flow systems and to the corresponding input data. In terms of migration related chemistry there appear to be large gaps in the underlying thermodynamic database for geochemical systems. Rock mechanical predictions are heavily dependent on knowing the location, structure and properties of dominant fractures; information which is extremely difficult to obtain. Conduction and convection of heat is understood well in principle. On the basis of this review, it appears that coupled migration modelling may not yet be at the stage of development that would allow its use as a standard modelling tool in performance assessments. However, a firmer basis for the conclusions reached can only be obtained after a systematic modelling exercise on a relevant and real migration problem has been carried out. (orig.)

  14. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    Domoto, Noboru; Masuda, Hiroyuki

    1989-01-01

    In a nuclear fuel assembly loaded with a plurality of fuel rods, the inside of a fuel rod disposed at a high neutron flux region is divided into an inner region and an outer region, and more burnable poisons are mixed in the inner region than in the outer region. Alternatively, the central portion of a pellet disposed in a high neutron flux region is made hollow, in which burnable poisons are charged. This can prevent neutron infinite multiplication factor from decreasing extremely at the initial burning stage. Further, the burnable poisons are not rapidly burnt completely and local peaking coefficient can be controlled. Accordingly, in a case of suppressing a predetermined excess reactivity by using a fuel rod incorporated with the burnable poison, the fuel economy can be improved more and the reactor core controllability can also be improved as compared with the usual case. (T.M.)

  15. Advanced Nuclear Fuel Cycle Effects on the Treatment of Uncertainty in the Long-Term Assessment of Geologic Disposal Systems - EBS Input

    International Nuclear Information System (INIS)

    Sutton, M.; Blink, J.A.; Greenberg, H.R.; Sharma, M.

    2012-01-01

    The Used Fuel Disposition (UFD) Campaign within the Department of Energy's Office of Nuclear Energy (DOE-NE) Fuel Cycle Technology (FCT) program has been tasked with investigating the disposal of the nation's spent nuclear fuel (SNF) and high-level nuclear waste (HLW) for a range of potential waste forms and geologic environments. The planning, construction, and operation of a nuclear disposal facility is a long-term process that involves engineered barriers that are tailored to both the geologic environment and the waste forms being emplaced. The UFD Campaign is considering a range of fuel cycles that in turn produce a range of waste forms. The UFD Campaign is also considering a range of geologic media. These ranges could be thought of as adding uncertainty to what the disposal facility design will ultimately be; however, it may be preferable to thinking about the ranges as adding flexibility to design of a disposal facility. For example, as the overall DOE-NE program and industrial actions result in the fuel cycles that will produce waste to be disposed, and the characteristics of those wastes become clear, the disposal program retains flexibility in both the choice of geologic environment and the specific repository design. Of course, other factors also play a major role, including local and State-level acceptance of the specific site that provides the geologic environment. In contrast, the Yucca Mountain Project (YMP) repository license application (LA) is based on waste forms from an open fuel cycle (PWR and BWR assemblies from an open fuel cycle). These waste forms were about 90% of the total waste, and they were the determining waste form in developing the engineered barrier system (EBS) design for the Yucca Mountain Repository design. About 10% of the repository capacity was reserved for waste from a full recycle fuel cycle in which some actinides were extracted for weapons use, and the remaining fission products and some minor actinides were encapsulated

  16. ADVANCED NUCLEAR FUEL CYCLE EFFECTS ON THE TREATMENT OF UNCERTAINTY IN THE LONG-TERM ASSESSMENT OF GEOLOGIC DISPOSAL SYSTEMS - EBS INPUT

    Energy Technology Data Exchange (ETDEWEB)

    Sutton, M; Blink, J A; Greenberg, H R; Sharma, M

    2012-04-25

    The Used Fuel Disposition (UFD) Campaign within the Department of Energy's Office of Nuclear Energy (DOE-NE) Fuel Cycle Technology (FCT) program has been tasked with investigating the disposal of the nation's spent nuclear fuel (SNF) and high-level nuclear waste (HLW) for a range of potential waste forms and geologic environments. The planning, construction, and operation of a nuclear disposal facility is a long-term process that involves engineered barriers that are tailored to both the geologic environment and the waste forms being emplaced. The UFD Campaign is considering a range of fuel cycles that in turn produce a range of waste forms. The UFD Campaign is also considering a range of geologic media. These ranges could be thought of as adding uncertainty to what the disposal facility design will ultimately be; however, it may be preferable to thinking about the ranges as adding flexibility to design of a disposal facility. For example, as the overall DOE-NE program and industrial actions result in the fuel cycles that will produce waste to be disposed, and the characteristics of those wastes become clear, the disposal program retains flexibility in both the choice of geologic environment and the specific repository design. Of course, other factors also play a major role, including local and State-level acceptance of the specific site that provides the geologic environment. In contrast, the Yucca Mountain Project (YMP) repository license application (LA) is based on waste forms from an open fuel cycle (PWR and BWR assemblies from an open fuel cycle). These waste forms were about 90% of the total waste, and they were the determining waste form in developing the engineered barrier system (EBS) design for the Yucca Mountain Repository design. About 10% of the repository capacity was reserved for waste from a full recycle fuel cycle in which some actinides were extracted for weapons use, and the remaining fission products and some minor actinides were

  17. Consideration of critically when directly disposing highly enriched spent nuclear fuel in unsaturated tuff: Bounding estimates

    International Nuclear Information System (INIS)

    Rechard, R.P.; Tierney, M.S.; Sanchez, L.C.; Martell, M.-A.

    1996-05-01

    This report presents one of 2 approaches (bounding calculations) which were used in a 1994 study to examine the possibility of a criticality in a repository. Bounding probabilities, although rough, point to the difficulty of creating conditions under which a critical mass could be assembled (container corrosion, separation of neutron absorbers from fissile material, collapse or precipitation of fissile material) and how significant the geochemical and hydrologic phenomena are. The study could not conceive of a mechanism consistent with conditions under which an atomic explosion could occur. Should a criticality occur in or near a container in the future, boundary consequence calculations showed that fissions from one critical event ( 20 fissions, if similar to aqueous and metal accidents and experiments) are quite small compared to the amount of fissions represented by the spent fuel itself. If it is assumed that the containers necessary to hold the highly enriched spent fuel went critical once per day for 1 million years, creating an energy release of about 10 20 fissions, the number of fissions equals about 10 28 , which corresponds to only 1% of the fission inventory in a repository containing 70,000 metric tons of heavy metal, the expected size for the proposed repository at Yucca Mountain, Nevada

  18. Consideration of critically when directly disposing highly enriched spent nuclear fuel in unsaturated tuff: Bounding estimates

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P.; Tierney, M.S.; Sanchez, L.C.; Martell, M.-A.

    1996-05-01

    This report presents one of 2 approaches (bounding calculations) which were used in a 1994 study to examine the possibility of a criticality in a repository. Bounding probabilities, although rough, point to the difficulty of creating conditions under which a critical mass could be assembled (container corrosion, separation of neutron absorbers from fissile material, collapse or precipitation of fissile material) and how significant the geochemical and hydrologic phenomena are. The study could not conceive of a mechanism consistent with conditions under which an atomic explosion could occur. Should a criticality occur in or near a container in the future, boundary consequence calculations showed that fissions from one critical event (<10{sup 20} fissions, if similar to aqueous and metal accidents and experiments) are quite small compared to the amount of fissions represented by the spent fuel itself. If it is assumed that the containers necessary to hold the highly enriched spent fuel went critical once per day for 1 million years, creating an energy release of about 10{sup 20} fissions, the number of fissions equals about 10{sup 28}, which corresponds to only 1% of the fission inventory in a repository containing 70,000 metric tons of heavy metal, the expected size for the proposed repository at Yucca Mountain, Nevada.

  19. The Environmental Protection Agency's Safety Standards for Disposal of Spent Nuclear Fuel: Potential Path Forward in Response to the Report of the Blue Ribbon Commission on America's Nuclear Future - 13388

    International Nuclear Information System (INIS)

    Forinash, Betsy; Schultheisz, Daniel; Peake, Tom

    2013-01-01

    Following the decision to withdraw the Yucca Mountain license application, the Department of Energy created a Blue Ribbon Commission (BRC) on America's Nuclear Future, tasked with recommending a national strategy to manage the back end of the nuclear fuel cycle. The BRC issued its final report in January 2012, with recommendations covering transportation, storage and disposal of spent nuclear fuel (SNF); potential reprocessing; and supporting institutional measures. The BRC recommendations on disposal of SNF and high-level waste (HLW) are relevant to the U.S. Environmental Protection Agency (EPA), which shares regulatory responsibility with the Nuclear Regulatory Commission (NRC): EPA issues 'generally applicable' performance standards for disposal repositories, which are then implemented in licensing. For disposal, the BRC endorses developing one or more geological repositories, with siting based on an approach that is adaptive, staged and consent-based. The BRC recommends that EPA and NRC work cooperatively to issue generic disposal standards-applying equally to all sites-early in any siting process. EPA previously issued generic disposal standards that apply to all sites other than Yucca Mountain. However, the BRC concluded that the existing regulations should be revisited and revised. The BRC proposes a number of general principles to guide the development of future regulations. EPA continues to review the BRC report and to assess the implications for Agency action, including potential regulatory issues and considerations if EPA develops new or revised generic disposal standards. This review also involves preparatory activities to define potential process and public engagement approaches. (authors)

  20. The development of rock suitability classification strategies in the Finnish spent nuclear fuel disposal program

    Energy Technology Data Exchange (ETDEWEB)

    Hellae, Pirjo; Hagros, Annika [Saanio and Riekkola Oy (Finland); Aaltonen, Ismo; Kosunen, Paula; Mattila, Jussi [Posiva Oy (Finland)

    2015-07-01

    This paper describes the development of the rock suitability classification strategies applied to locate the spent fuel repository in crystalline rock in Finland. Development of the classification procedure is motivated not only by the regulatory requirements, but also by the need to more closely integrate site characterization, repository design and long-term safety assessment. The classification procedure has been developed along with the increasing level of detail of the available site data and knowledge on the performance of the engineered barrier system (EBS). The classification system has also been adapted to the changes in the regulations. The present form of the classification system and experiences from testing the system at the site are described. Demonstration activities have shown that the criteria and the stepwise research, construction and decision making protocol can be applied successfully.

  1. The development of rock suitability classification strategies in the Finnish spent nuclear fuel disposal program

    International Nuclear Information System (INIS)

    Hellae, Pirjo; Hagros, Annika; Aaltonen, Ismo; Kosunen, Paula; Mattila, Jussi

    2015-01-01

    This paper describes the development of the rock suitability classification strategies applied to locate the spent fuel repository in crystalline rock in Finland. Development of the classification procedure is motivated not only by the regulatory requirements, but also by the need to more closely integrate site characterization, repository design and long-term safety assessment. The classification procedure has been developed along with the increasing level of detail of the available site data and knowledge on the performance of the engineered barrier system (EBS). The classification system has also been adapted to the changes in the regulations. The present form of the classification system and experiences from testing the system at the site are described. Demonstration activities have shown that the criteria and the stepwise research, construction and decision making protocol can be applied successfully.

  2. Final Disposal of Nuclear Waste. The Swedish National Council for Nuclear Waste's Review of the Swedish Nuclear Fuel and Waste Management Co's (SKB's) RDandD Programme 2007

    International Nuclear Information System (INIS)

    2009-01-01

    and operation and providing guidelines for technology development and research. An important purpose of a systems analysis is to describe and explain which parameters can or should be kept open for modification and improvement, and when decisions must be made to finalize these parameters. The Council finds that systems analysis methodology is valuable as part of a learning process that is controlled by the stakeholders and that involves analysis from new angles and adjustment of the system boundary in a dialogue with the central actors. A coherent and clarifying account should be given of alternative methods for the final disposal of spent nuclear fuel. SKB should present such an account not later than in conjunction with the company's permit applications. The Council believes that SKB should in this account clearly explain its positions on the deep borehole concept. In this context, SKB should also explain its plans for KBS-3 with horizontal deposition. Regarding the Canister: The material and casting process for the nodular iron insert must be optimized so that specified requirements can be met. Otherwise some other type of material must be used. In order to guarantee reliability during canister fabrication and final disposal, quality requirements must be developed with respect to fabrication defects in all parts of the canister, including welds. Continued corrosion studies are required in different areas: accelerated long-term stress corrosion cracking experiments, general corrosion in -chloride- and sulphide-containing water with bentonite, and microbial corrosion, as well as possible corrosion in oxygen-free water. General studies should be conducted regarding what effect existing and altered rock stresses may have on hydraulic conductivity in fractures in different directions and the consequences for the detailed design of the repository. Additional RandD on grouting for sealing of fractures is necessary. A better account should be given of the extent and

  3. Posiva's application for a decision in principle concerning a disposal facility for spent nuclear fuel. STUK's statement and preliminary safety appraisal

    Energy Technology Data Exchange (ETDEWEB)

    Ruokola, E. [ed.

    2000-03-01

    In May 1999, Posiva Ltd submitted to the Government an application, pursuant to the Nuclear Energy Act, for a Decision in Principle on a disposal facility for spent nuclear fuel from the Finnish nuclear power plants. The Ministry of Trade and Industry requested the Radiation and Nuclear Safety Authority (STUK) to draw up a preliminary safety appraisal concerning the proposed disposal facility. In the beginning of this report, STUK's statement to the Ministry and Industry concerning the proposed disposal facility is given. In that statement, STUK concludes that the Decision in Principle is currently justified from the standpoint of safety. The statement is followed by a safety appraisal, where STUK deems, how the proposed disposal concept, site and facility comply with the safety requirements included in the Government's Decision (478/1999). STUK's preliminary safety appraisal was supported by contributions from a number of outside experts. A collective opinion by an international group of ten distinguished experts is appended to this report. (orig.)

  4. Electromagnetic characterization of fractured rock for geological disposal studies of spent nuclear fuel

    International Nuclear Information System (INIS)

    Eloranta, E.; Ermutlu, M.; Flykt, M.; Lindell, I.; Nikoskinen, K.; Sihvola, A.

    1998-04-01

    In the report, the results of a joint research project carried out in 1991-1997 by the Finnish Radiation and Nuclear Safety Authority (STUK) and the Electromagnetics Laboratory of the Helsinki University of Technology are presented. The main purpose was to create computational models for electric potential responses when the medium is anisotropic and is bounded by a perfect magnetic conductor, a perfect electric conductor, and an anisotropic impedance surface. Furthermore, the geometry of two anisotropic half spaces and a layered medium were considered. The solutions of the problems were made using image theory. For modeling the electric potential in anisotropic medium with inhomogeneities, an integral equation was formulated. Also a wedge structure was treated as an extension to the traditional two parallel plate model of fracture geometry. The equivalentization of fracturing with anisotropy is a research area that still continues that still continues

  5. Electromagnetic characterization of fractured rock for geological disposal studies of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Eloranta, E. [Radiation and Nuclear Safety Authority, Helsinki (Finland); Ermutlu, M. [Nokia Research Center, Helsinki (Finland); Flykt, M.; Lindell, I.; Nikoskinen, K.; Sihvola, A. [Helsinki Univ. of Technology, Espoo (Finland). Electromagnetics Lab.

    1998-04-01

    In the report, the results of a joint research project carried out in 1991-1997 by the Finnish Radiation and Nuclear Safety Authority (STUK) and the Electromagnetics Laboratory of the Helsinki University of Technology are presented. The main purpose was to create computational models for electric potential responses when the medium is anisotropic and is bounded by a perfect magnetic conductor, a perfect electric conductor, and an anisotropic impedance surface. Furthermore, the geometry of two anisotropic half spaces and a layered medium were considered. The solutions of the problems were made using image theory. For modeling the electric potential in anisotropic medium with inhomogeneities, an integral equation was formulated. Also a wedge structure was treated as an extension to the traditional two parallel plate model of fracture geometry. The equivalentization of fracturing with anisotropy is a research area that still continues that still continues 46 refs. The publication contains also fourteen previous publications by authors

  6. Safety case for the disposal of spent nuclear fuel at Olkiluoto - Biosphere assessment 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-09-15

    Biosphere Assessment sits within Posiva Oy's safety case 'TURVA-2012' report portfolio and has the objectives of presenting the assessment methodology, a summary of the surface environment at the Olkiluoto site and an assessment of the surface environment scenarios that have been identified in Formulation of Radionuclide Release Scenarios. A base scenario, variant scenarios and disturbance scenarios are considered. For the base scenario, a Reference Case has been identified and analysed. For the other scenarios, a range of biosphere calculation cases has been identified and analysed. All calculation cases, except cases addressing inadvertent human intrusion, are based on repository calculation cases, assessed in Assessment of Radionuclide Release Scenarios, in which failure of a single spent fuel canister gives radionuclide releases to the biosphere within the dose assessment time window of ten millennia. The biosphere calculation cases take into account uncertainties in the development of the terrain and the ecosystems, land use, location of the releases to the surface environment, radionuclide transport properties and dietary profiles. The resulting annual doses to humans for all calculation cases for the base and variant scenarios are below the radiation dose constraints for most exposed people and other people, as set out by the Finnish regulator, generally by more than two orders of magnitude. The resulting absorbed doses rates to plants and animals for all calculation cases imply that any radiological impacts of these releases will be negligible (orig.)

  7. Safety case for the disposal of spent nuclear fuel at Olkiluoto - Biosphere assessment 2012

    International Nuclear Information System (INIS)

    2013-09-01

    Biosphere Assessment sits within Posiva Oy's safety case 'TURVA-2012' report portfolio and has the objectives of presenting the assessment methodology, a summary of the surface environment at the Olkiluoto site and an assessment of the surface environment scenarios that have been identified in Formulation of Radionuclide Release Scenarios. A base scenario, variant scenarios and disturbance scenarios are considered. For the base scenario, a Reference Case has been identified and analysed. For the other scenarios, a range of biosphere calculation cases has been identified and analysed. All calculation cases, except cases addressing inadvertent human intrusion, are based on repository calculation cases, assessed in Assessment of Radionuclide Release Scenarios, in which failure of a single spent fuel canister gives radionuclide releases to the biosphere within the dose assessment time window of ten millennia. The biosphere calculation cases take into account uncertainties in the development of the terrain and the ecosystems, land use, location of the releases to the surface environment, radionuclide transport properties and dietary profiles. The resulting annual doses to humans for all calculation cases for the base and variant scenarios are below the radiation dose constraints for most exposed people and other people, as set out by the Finnish regulator, generally by more than two orders of magnitude. The resulting absorbed doses rates to plants and animals for all calculation cases imply that any radiological impacts of these releases will be negligible (orig.)

  8. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    Wakamatsu, Mitsuo.

    1974-01-01

    Object: To improve a circulating flow passage of coolant so as to be able to accurately detect the temperature of coolant, rare gases contained, and the like. Structure: A fuel assembly comprising a flow regulating lattice provided with a plurality of communication holes in an axial direction, said lattice being positioned at the upper end of an outer tube in which nuclear fuel elements are received, and a neutron shielding body having a plurality of spiral coolant flow passages disposed between the lattice and the nuclear fuel elements, whereby a coolant comprised of liquid sodium or the like, which moves up passing through the coolant flow passages and the flow regulating passage, is regulated and passed through a detector mounted at the upper part of the flow regulating lattice to detect coolant temperature, flow rate, and rare gases or the like as the origin of nuclear fission contained in the coolant due to breakage of fuel elements. (Kamimura, M.)

  9. Issues related to the construction and operation of a geological disposal facility for nuclear fuel waste in crystalline rock - the Canadian experience

    International Nuclear Information System (INIS)

    Allan, C.J.; Baumgartner, P.; Ohta, M.M.; Simmons, G.R.; Whitaker, S.H.

    1997-12-01

    The siting, design, construction, operation, decommissioning, and closure of a geological facility for the disposal of nuclear fuel waste is a complex undertaking that will span many decades. Both technical and social issues must be taken into account simultaneously and many factors must be considered. Based on studies carried out in Canada and elsewhere, it appears that these factors can be accommodated and that geological disposal is both technically and socially feasible. But throughout the different stages of implementing disposal, technical and social issues will continue to arise and these will have to be dealt with successfully if progress is to continue. This paper discusses these issues and a proposed approach for dealing with them. (author)

  10. Identification of contaminants of concern for the postclosure assessment of the concept for the disposal of Canada`s nuclear fuel waste

    Energy Technology Data Exchange (ETDEWEB)

    Goodwin, B W; Mehta, K K

    1994-03-01

    The concept for the disposal of Canada`s nuclear fuel waste involves the isolation of irradiated fuel in corrosion-resistant containers emplaced din din a vault located deep in crystalline rock of the Canadian Shield. To estimate potential impacts on members of a critical group far into the future, a postclosure assessment evaluates the long-term safety of the concept. Although the nuclear fuel waste from CANDU (Canada Deuterium Uranium) power generating stations contains several hundreds of potentially toxic radionuclides and chemical elements (referred to as contaminants), many of these would not lead to significant impacts. This report provides an upper bound on estimated radiation dose and chemical toxicity effects on humans from all potentially toxic contaminants, and it identifies those that require detailed consideration in the postclosure assessment. This report also examines the origins and properties of the contaminants. Properties of interest include radioactive half-life, inventory, mobility in groundwaters and sorption on rock, degree of toxicity, and precursors and progeny (or parents and daughters) for members of a decay chain. The report considers how these properties affect the behaviour of different contaminants in different parts of the disposal system. The discussion leads to suggested methods of treatment of different contaminants when simulating their fate within the disposal system. In particular, recommendations are made on how the actinide decay chains can be simplified for study in the postclosure assessment. (author). 56 refs., 22 tabs., 12 figs.

  11. Environmental standards for management and disposal of spent nuclear fuel, high-level and transuranic radioactive wastes, 40 CFR part 191: draft environmental impact statement

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The establishment of environmental standards for management and disposal of spent nuclear reactor fuel and high-level and transuranic radioactive wastes is proposed. The standards would require that maximum individual doses from all normal operations be limited to 25 millirem to the whole body, 75 millirem to the thyroid, and 25 millirem to any other organ. Regarding disposal of subject materials in geologic sites, the standards would include numerical containment requirements for the first 10,000 years following disposal, assurance requirements, and procedural requirements. The assurance requirements would provide seven principles necessary for developing confidence that long-term containment requirements would be upheld. The principles would call for well-designed, multiple-barrier disposal systems that would not rely on future generations for maintenance and would not be located near potential valuable resources. The principles would also require that future generations be provided with information about the location and dangers of the wastes and an option to recover the wastes if necessary. Procedural requirements would be developed to assure that the containment requirements were upheld. The implementation of the standards would protect public health and the environment against emissions of radioactivity. The maximum impact expected from a disposal system complying with the proposed standards would be less than 1000 premature cancer deaths over the first 10,000 years for disposal of high-level wastes produced by all currently operating reactors over their lifetime

  12. Transport and nuclear waste disposal

    International Nuclear Information System (INIS)

    Wild, E.

    1999-01-01

    The author assesses both past and future of nuclear waste disposal in Germany. The failure of the disposal concept is, he believes, mainly the fault of the Federal Government. On the basis of the Nuclear Energy Act, the government is obliged to ensure that ultimate-storage sites are established and operated. Up to the present, however, the government has failed - apart from the episode in Asse and Morsleben and espite existing feasible proposals in Konrad and Gorleben - to achieve this objective. This negative development is particularly evident from the projects which have had to be prematurely abandoned. The costs of such 'investment follies' meanwhile amount to several billion DM. At least 92% of the capacity in the intermediate-storage sites are at present unused. Following the closure of the ultimate-storage site in Morsleben, action must be taken to change over to long-term intermediate-storage of operational waste. The government has extensive intermediate-storage capacity at the intermediate-storage site Nord in Greifswald. There, the wate originally planned for storage in Morsleben could be intermediately stored at ERAM-rates. Nuclear waste transportation, too, could long ago have been resumed, in the author's view. For the purpose of improving the transport organisation, a new company was founded which represents exclusively the interests of the reprocessing firms at the nuclear power stations. The author's conclusion: The EVU have done their homework properly and implemented all necessary measures in order to be able to resume transport of fuel elements as soon as possible. The generating station operators favour a solution based upon agreement with the Federal Government. The EVU have already declared their willingness - in the event of unanimous agreement - to set up intermediate-storage sites near the power stations. The ponds in the generating stations, however, are unsuitable for use as intermediate-storage areas. If intermediate-storage areas for

  13. The social impacts of the final disposal of spent nuclear fuel from the point of view of the inhabitants. Interview research

    International Nuclear Information System (INIS)

    Viinikainen, T.

    1998-12-01

    The research studied the social impacts of the final disposal of spent nuclear fuel by the means of qualitative methods. The principal research material consisted of 49 theme interviews carried out in four municipalities, Eurajoki, Kuhmo, Loviisa and Aeaenekoski, all of which have a candidate site for spent fuel disposal. The interviews covered residents living near the possible disposal site, local authorities from different sectors of the municipality, social workers, youth workers and teachers, local businesses, trade and other organisations as well as environmental and citizen movements. When considering the risk conceptions and worries over safety, a fairly consistent view on the safety of the different phases of the project can be identified in all the municipalities. The transportation of nuclear waste aroused definitely the most worries over safety, especially because of the danger of sabotage and traffic accidents. When considering the encapsulation stage' the interviews revealed that risks are associated with this stage because it entails a 'human factor': the treatment of a dangerous substance in a disposal site above ground is considered hazardous. When considering the time after the closing of the disposal system, an opinion could be formed on the basis of the interviews that a final disposal system in hard bedrock would probably perform adequately in the short term but there can be no certain knowledge of risks in the long term. Confidence or lack of confidence in the safety of the project appeared as the most important factor causing social impacts. As a summary of the results, it can be concluded that especially (1) familiarity of the risk and (2) the possibility that taking risks are advantageous to oneself increase the acceptability of the risk. These are also the factors which distinguish the municipalities with nuclear power plants (Loviisa and Eurajoki) from the other two municipalities. The fair allocation of risks as well as the division of

  14. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Rechard, R.P.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste. Although numerous caveats must be placed on the results, the general findings were as follows: Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories

  15. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory. Volume 1, Methodology and results

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [ed.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste. Although numerous caveats must be placed on the results, the general findings were as follows: Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories.

  16. INERT-MATRIX FUEL: ACTINIDE ''BURNING'' AND DIRECT DISPOSAL

    International Nuclear Information System (INIS)

    Rodney C. Ewing; Lumin Wang

    2002-01-01

    Excess actinides result from the dismantlement of nuclear weapons (Pu) and the reprocessing of commercial spent nuclear fuel (mainly 241 Am, 244 Cm and 237 Np). In Europe, Canada and Japan studies have determined much improved efficiencies for burnup of actinides using inert-matrix fuels. This innovative approach also considers the properties of the inert-matrix fuel as a nuclear waste form for direct disposal after one-cycle of burn-up. Direct disposal can considerably reduce cost, processing requirements, and radiation exposure to workers

  17. Final disposal of spent nuclear fuel - regulatory system and roles of different actors during the decision process

    International Nuclear Information System (INIS)

    2009-03-01

    In November 2006 Swedish Nuclear Fuels Co. applied for a license to build a plant for encapsulation of spent nuclear fuels at Oskarshamn, Sweden. The company also have plans to apply, in 2009, for a license to construct a underground repository for spent nuclear fuels. KASAM arranged a seminar in November 2006 in order to describe and discuss the licensing rules and regulations and the roles of different parties in the decision making. Another objective of the seminar was to point out possible ambiguities in this process. Another interesting question under discussion was in what ways the basic data for the decision should be produced. The seminar covered the part of the process beginning with the application for a license and ending with the government approval/rejection of the application. Most time was spent on the legal aspects of the process

  18. Final disposal of spent nuclear fuel - regulatory system and roles of different actors during the decision process

    Energy Technology Data Exchange (ETDEWEB)

    2009-03-15

    In November 2006 Swedish Nuclear Fuels Co. applied for a license to build a plant for encapsulation of spent nuclear fuels at Oskarshamn, Sweden. The company also have plans to apply, in 2009, for a license to construct a underground repository for spent nuclear fuels. KASAM arranged a seminar in November 2006 in order to describe and discuss the licensing rules and regulations and the roles of different parties in the decision making. Another objective of the seminar was to point out possible ambiguities in this process. Another interesting question under discussion was in what ways the basic data for the decision should be produced. The seminar covered the part of the process beginning with the application for a license and ending with the government approval/rejection of the application. Most time was spent on the legal aspects of the process

  19. Final disposal of spent nuclear fuels - regulations and the roles of different stakeholders during the decision making process

    International Nuclear Information System (INIS)

    2007-05-01

    In November 2006 Swedish Nuclear Fuels Co. applied for a license to build a plant for encapsulation of spent nuclear fuels at Oskarshamn, Sweden. The company also have plans to apply, in 2009, for a license to construct a underground repository for spent nuclear fuels. KASAM arranged a seminar in November 2006 in order to describe and discuss the licensing rules and regulations and the roles of different parties in the decision making. Another objective of the seminar was to point out possible ambiguities in this process. Another interesting question under discussion was in what ways the basic data for the decision should be produced. The seminar covered the part of the process beginning with the application for a license and ending with the government approval/rejection of the application. Most time was spent on the legal aspects of the process

  20. Supply, operation and radioactive waste disposal of nuclear power plants

    International Nuclear Information System (INIS)

    Mohrhauer, H.; Krey, M.; Haag, G.; Wolters, J.; Merz, E.; Sauermann, P.F.

    1981-07-01

    The subject of 'Nuclear Fuel Cycle' is treated in 5 reports: 1. Uranium supply; 2. Fabrication and characteristics of fuel elements; 3. Design, operation and safety of nuclear power plants after Harrisburg; 4. Radioactive waste disposal of nuclear power plants - changed political scenery after 1979; 5. Shutdown and dismantling of LWR-KKW - state of knowledge and feasibility. (HP) [de

  1. User's manual for the CC3 computer models of the concept for disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    Dougan, K.D.; Wojciechowski, L.C.

    1995-06-01

    Atomic Energy of Canada Limited (AECL) is assessing a concept for disposing of CANDU reactor fuel waste in a vault deep in plutonic rock of the Canadian Shield. A computer program called the Systems Variability Analysis Code (SYVAC) has been developed as an analytical tool for the postclosure (long-term) assessment of the concept, and for environmental assessments of other systems. SYVAC3, the third generation of the code, is an executive program that directs repeated simulation of the disposal system, which is represented by the CC3 (Canadian Concept, generation 3) models comprising a design-specific vault, a site-specific geosphere and a biosphere typical of the Canadian Shield. (author). 23 refs., 7 tabs., 21 figs

  2. On the Impact of the Fuel Dissolution Rate Upon Near-Field Releases From Nuclear Waste Disposal

    Directory of Open Access Journals (Sweden)

    A Pereira

    2016-09-01

    Full Text Available Calculations of the impact of the dissolution of spent nuclear fuel on the release from a damaged canister in a KBS-3 repository are presented. The dissolution of the fuel matrix is a complex process and the dissolution rate is known to be one of the most important parameters in performance assessment models of the near-field of a geological repository. A variability study has been made to estimate the uncertainties associated with the process of fuel dissolution. The model considered in this work is a 3D model of a KBS-3 copper canister. The nuclide used in the calculations is Cs-135. Our results confirm that the fuel degradation rate is an important parameter, however there are considerable uncertainties associated with the data and the conceptual models. Consequently, in the interests of safety one should reduce, as far as possible, the uncertainties coupled to fuel degradation.

  3. The disposal of Canada`s nuclear fuel waste: a study of postclosure safety of in-room emplacement of used CANDU fuel in copper containers in permeable plutonic rock volume 1: summary

    Energy Technology Data Exchange (ETDEWEB)

    Wikjord, A G; Baumgartner, P; Johnson, L H; Stanchell, F W; Zach, R; Goodwin, B W

    1996-06-01

    The concept for disposal of Canada`s nuclear fuel waste involves isolating the waste in corrosion-resistant containers emplaced and sealed within a vault at a depth of 500 to 1000 m in plutonic rock of the Canadian Shield. The case for the acceptability of the concept as a means of safely disposing of Canada`s nuclear fuel waste is presented in an Environmental Impact Statement (EIS) The disposal concept permits a choice of methods, materials, site locations and designs. The EIS presents a case study of the long-term (i.e., postclosure) performance of a hypothetical implementation of the concept, referred to in this report as the reference disposal system. The reference disposal system is based on borehole emplacement of used CANDU fuel in Grade-2 titanium alloy containers in low-permeability, sparsely fractured plutonic rock of the Canadian Shield. We evaluate the long-term performance of another hypothetical implementation of the concept based on in-room emplacement of used CANDU fuel in copper containers in permeable plutonic rock. The geological characteristics of the geosphere assumed for this study result in short groundwater travel times from the disposal vault to the surface. In the present study, the principal barrier to the movement of contaminants is the long-lasting copper container. We show that the long-lasting container can effectively compensate for a permeable host rock which results in an unfavourable groundwater flow condition. These studies illustrate the flexibility of AECL`s disposal concept to take advantage of the retention, delay, dispersion, dilution and radioactive decay of contaminants in a system of natural barriers provided by the geosphere and hydrosphere and of engineered barriers provided by the waste form, container, buffer, backfills, other vault seals and grouts. In an actual implementation, the engineered system would be designed for the geological conditions encountered at the host site. 34 refs., 2 tabs., 11 figs.

  4. The disposal of Canada's nuclear fuel waste: a study of postclosure safety of in-room emplacement of used CANDU fuel in copper containers in permeable plutonic rock volume 1: summary

    International Nuclear Information System (INIS)

    Wikjord, A.G.; Baumgartner, P.; Johnson, L.H.; Stanchell, F.W.; Zach, R.; Goodwin, B.W.

    1996-06-01

    The concept for disposal of Canada's nuclear fuel waste involves isolating the waste in corrosion-resistant containers emplaced and sealed within a vault at a depth of 500 to 1000 m in plutonic rock of the Canadian Shield. The case for the acceptability of the concept as a means of safely disposing of Canada's nuclear fuel waste is presented in an Environmental Impact Statement (EIS) The disposal concept permits a choice of methods, materials, site locations and designs. The EIS presents a case study of the long-term (i.e., postclosure) performance of a hypothetical implementation of the concept, referred to in this report as the reference disposal system. The reference disposal system is based on borehole emplacement of used CANDU fuel in Grade-2 titanium alloy containers in low-permeability, sparsely fractured plutonic rock of the Canadian Shield. We evaluate the long-term performance of another hypothetical implementation of the concept based on in-room emplacement of used CANDU fuel in copper containers in permeable plutonic rock. The geological characteristics of the geosphere assumed for this study result in short groundwater travel times from the disposal vault to the surface. In the present study, the principal barrier to the movement of contaminants is the long-lasting copper container. We show that the long-lasting container can effectively compensate for a permeable host rock which results in an unfavourable groundwater flow condition. These studies illustrate the flexibility of AECL's disposal concept to take advantage of the retention, delay, dispersion, dilution and radioactive decay of contaminants in a system of natural barriers provided by the geosphere and hydrosphere and of engineered barriers provided by the waste form, container, buffer, backfills, other vault seals and grouts. In an actual implementation, the engineered system would be designed for the geological conditions encountered at the host site. 34 refs., 2 tabs., 11 figs

  5. Final disposal of spent nuclear fuel in Sweden. Some unresolved issues and challenges in the design and implementation of the forthcoming planning and EIA processes

    Energy Technology Data Exchange (ETDEWEB)

    Bjarnadottir, H.; Hilding-Rydevik, T. [Nordregio, Stockholm (Sweden)

    2001-06-01

    The aim of the study is to highlight some unresolved and challenging issues in the forthcoming approximately six year long Environmental Impact Assessment (EIA) and planning process of the long-term disposal of spent nuclear fuel in Sweden. Different international and Nordic experiences of the processes for final disposal as well as from other development of similar scope, where experiences assumed to be of importance for final disposal of nuclear waste, have been described. Furthermore, issues relating to 'good EIA practice' as well as certain aspects of planning theory have also been presented. The current Swedish situation for the planning and EIA process of the final disposal of spent nuclear fuel was also been summarized. These different 'knowledge areas' have been compared and measured against our perception of the expectations towards the forthcoming process, put forward by different Swedish actors in the field. The result is a presentation of a number of questions and identification issues that the authors consider need special attention in the design and conduction of the planning and EIA process. The study has been realized through a literature survey and followed by reading and analysis of the written material. The main focus of the literature search was on material describing planning processes, actor perspectives and EIA. Material and literature on the technical and scientific aspects of spent nuclear fuel disposal was however deliberately avoided. There is a wealth of international and Swedish literature concerning final disposal of spent nuclear fuel - concerning both technical issues and issues concerning for example public participation and risk perception. But material of a more systematic and comparative nature (relating to both empirical and theoretical issues, and to practical experiences) in relation to EIA processes and communicative planning for final disposal of spent nuclear fuel seems to be more sparsely represented

  6. Quantitative and radiological assessment of PYRO-SFR closed fuel cycle against direct disposal of spent nuclear fuel from Korean nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Muhammad Minhaj; Lee, Suhong; Cheong, Jaehak; Whang, Jooho [Kyunghee University, Seoul (Korea, Republic of)

    2016-12-15

    Calculations have been made to estimate the generation of SNF including Plutonium (Pu) and minor actinides (MAs) from PWR and PHWR NPPs by using the IAEA code Nuclear Fuel Cycle Simulation System (NFCSS) for the period of 2016, 2030 as 12 more NPPs will be added by the year 2029. In order to find the optimize option for SNF management through sustainable use of nuclear energy system and reduce the associated radiological risk, 4 scenarios to burnout the Pu and MAs are analyzed. Estimation for the amount of SNF including major radionuclides has made for the year of 2016, 2030, 2089 and 2109 with an approximate amount of 148,19.65MT, 248,34.6 MT, 41572.23 MT and 61272.24 MT of SNF will be generated respectively. Radioactivity and radiotoxicity is calculated in order to access the radiological risk in terms of ingestion. Four Transmutation strategies is predicted to make Korean NPPs sustainable by incorporating KALIMER-600 (Burner) reactor in Korean nuclear fleet with an approximate transmutation rate of 99.77%, 96.57%, 95.34% and 97.58% for MA only (scenario-1), (MA & Pu) scenario-2, scenario-3 (MA only till the year 2125) and scenario-4 MA & Pu till the year 2148) respectively.

  7. A practical approach to the disposal of highly toxic and long-lived spent nuclear fuel waste between Venus and Earth

    International Nuclear Information System (INIS)

    Ehricke, K.A.

    1983-01-01

    Extraterrestrial disposal, while not the only alternative, nevertheless assures definite and irreversible removal of the most toxic and long-lived waste from the biosphere. The disposal 'site' should lie at minimum safe transfer energy level. Primary candidate is the space between Venus and Earth. The number of propulsion phases should be a minimum, preferably only one. Lunar gravity assist can be helpful to achieve higher inclination of the heliocentric orbit relative to the ecliptic. Solidified spent fuel isotopes and actinides, sufficient to reduce the residual terrestrial waste to the radiation level of natural uranium deposits after 30 to 40 yr instead of 1000 to 1500 yr, is deposited into heliocentric orbits. Transportation systems, requirements, costs and the associated socio-economic benefit potentials of an environmentally more benign and a more vigorous nuclear power generation program are presented. Prior to solidification, an interim storage of 10 yr, following removal from the reactor, may be required. The Shuttle, with one Orbiter modified as Nuclear Waste Carrying Orbiter and an out of near-Earth orbit booster, provides a safe and economic transportation system at disposal mission costs from surface to disposal orbit of less than 0.5 cents/kWhe or <= 0.1 cent/kWhe depending on level of orbital operations. Details are discussed. (author)

  8. NWTS program criteria for mined geologic disposal of nuclear waste: functional requirements and performance criteria for waste packages for solidified high-level waste and spent fuel

    International Nuclear Information System (INIS)

    1982-07-01

    The Department of Energy (DOE) has primary federal responsibility for the development and implementation of safe and environmentally acceptable nuclear waste disposal methods. Currently, the principal emphasis in the program is on emplacement of nuclear wastes in mined geologic repositories well beneath the earth's surface. A brief description of the mined geologic disposal system is provided. The National Waste Terminal Storage (NWTS) program was established under DOE's predecessor, the Energy Research and Development Administration, to provide facilities for the mined geologic disposal of radioactive wastes. The NWTS program includes both the development and the implementation of the technology necessary for designing, constructing, licensing, and operating repositories. The program does not include the management of processing radioactive wastes or of transporting the wastes to repositories. The NWTS-33 series, of which this document is a part, provides guidance for the NWTS program in the development and implementation of licensed mined geologic disposal systems for solidified high-level and transuranic (TRU) wastes. This document presents the functional requirements and performance criteria for waste packages for solidified high-level waste and spent fuel. A separate document to be developed, NWTS-33(4b), will present the requirements and criteria for waste packages for TRU wastes. The hierarchy and application of these requirements and criteria are discussed in Section 2.2

  9. Management of radioactive fuel wastes: the Canadian disposal program

    International Nuclear Information System (INIS)

    Boulton, J.

    1978-10-01

    This report describes the research and development program to verify and demonstrate the concepts for the safe, permanent disposal of radioactive fuel wastes from Canadian nuclear reactors. The program is concentrating on deep underground disposal in hard-rock formations. The nature of the radioactive wastes is described, and the options for storing, processing, packaging and disposing of them are outlined. The program to verify the proposed concept, select a suitable site and to build and operate a demonstration facility is described. (author)

  10. Performance assessment of the direct disposal in unsaturated tuff or spent nuclear fuel and high-level waste owned by USDOE: Volume 2, Methodology and results

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [ed.

    1995-03-01

    This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservations. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM.

  11. Performance assessment of the direct disposal in unsaturated tuff or spent nuclear fuel and high-level waste owned by USDOE: Volume 2, Methodology and results

    International Nuclear Information System (INIS)

    Rechard, R.P.

    1995-03-01

    This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservations. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM

  12. Mire succession and balance of key elements in relation to crustal uplift and spent nuclear fuel disposal

    Energy Technology Data Exchange (ETDEWEB)

    Aro, L. [Finnish Forest Research Institute (Finland); Ikonen, A.T.K. [Environmental Research and Assessment EnviroCase Ltd (Finland)

    2014-07-01

    Olkiluoto Island on the western coast of Finland has been selected as a repository site for spent nuclear fuel disposal. Olkiluoto is subjected to post-glacial crustal uplift, 6-8 mm/year. This changes landscape and creates new ecosystems, e.g. mires, to be developed further due to changes in groundwater table, site properties and prevailing vegetation in future. The biosphere assessment demonstrating the long-term safety of the repository is developed into more and more site specific. In the biosphere assessment, terrestrial ecosystems are divided into upland forests (three biotopes) and mires. Mires are not well represented at the site at present. However, over the assessment timeframe, 10,000 years, there will be a succession of mire development stages that need to be considered. There are various stages ranging from brackish marshes through minerotrophic treed and treeless mires to ombrotrophic bogs that can ultimately be overgrown by terrestrial plants. At this final stage of development there are no connections to ground or surface waters so the only source of water is from precipitation. Hence, there are very different properties between the different mires. The properties of the future mire ecosystems surrounding Olkiluoto Island can be projected from the past and radionuclide transport models applied based on the properties of present mires, both on Olkiluoto Island and in a reference area. A set of reference mires have therefore been selected on the basis that they are as similar as possible to the types that are expected to develop during the next 10,000 years. The most important radionuclides in transport models are long-lived C-14, Cl-36, I-129, Mo-93, Se-79, Cs-135, Ni-59 and Nb-94. Due to low or non-existent concentrations of many of these nuclides in the environment, stable isotopes are used as analogues in certain cases, e.g. Ni instead of Ni-59. In this presentation we demonstrate the subject by estimating distribution of stable Ni in mires at

  13. Consideration of Nuclear Criticality When Directly Disposing Highly Enriched Spent Nuclear Fuel in Unsaturated Tuff - II: Geochemical Constraints

    International Nuclear Information System (INIS)

    Rechard, Rob P.; Sanchez, Lawrence C.; Trellue, Holly R.

    2003-01-01

    This article presents several reasonable cases in which four mechanisms - dissolution, physical mixing, adsorption, and precipitation (either chemical change or evaporation) - might concentrate fissile material in and around a disposal container for radioactive waste at the proposed repository at Yucca Mountain, Nevada. The possible masses, concentrations, and volume are then compared to criticality limits. The cases examined evaluate the geologic barrier role in preventing criticality since engineered options for preventing criticality (e.g., boron or gadolinium neutron absorber in the disposal container) are not considered. The solid concentrations able to form in the natural environment are insufficient for criticality to occur because (a) solutions of 235 U and 239 Pu are clearly not critical; (b) physical mixing of fissile material with the entire potential iron oxide (as goethite - FeOOH) in a waste package is not critical; (c) the adsorption of 239 Pu on consolidated iron oxide in a waste package is not critical; (d) the adsorption of 235 U on consolidated iron oxide in a waste package is not critical when accounting for reduced adsorption because of carbonates at high pH; (e) the filtration of iron oxide colloids, containing fissile material, by the thin invert material is not critical; (f) insufficient retention through precipitation of 235 U or 239 Pu occurs in the invert; (g) adsorption of 235 U and 239 Pu on devitrified or clinoptolite-rich tuff below the repository is not critical; (h) the average precipitation/adsorption of 235 U as uranyl silicates in the tuff is not critical by analogy with calcite deposition in lithophysae at Yucca Mountain; and (i) precipitation/adsorption (caused by cyclic drying) as uranyl silicates on fracture surfaces of the tuff is not critical by analogy with the oxidation of UO 2 , migration of U VI , and precipitation in fractures at the Nopal I ore deposit in Mexico

  14. Investigations of possibilities to dispose of spent nuclear fuel in Lithuania: a model case. Volume 3, Generic Safety Assessment of Repository in Crystalline Rocks

    International Nuclear Information System (INIS)

    Motiejunas, S.; Poskas, P.

    2005-01-01

    In this Volume a generic safety assessment of the repository for spent nuclear fuel in crystalline rock in Lithuania is presented. Modeling of safety relevant radionuclide release from the defected canister and their transport through the near field and far field was performed. Doses to humans due to released radionuclides in the well water were calculated and compared with the dose restrictions existing in Lithuania. For this stage of generic safety assessment only two scenarios were chosen: base scenario and canister defect scenario. KBS-3 concept developed by SKB for disposal of spent nuclear fuel in Sweden was chosen as prototype for repository in crystalline basement in Lithuania. The KBS-3H design with horizontal canister emplacement is proposed as a reference design for Lithuania

  15. Implications of monitored retrievable storage for geologic disposal of spent nuclear fuel and high level radioactive waste

    International Nuclear Information System (INIS)

    Halstead, R.J.; Kidwell, S.M.; Woodbury, D.

    1986-01-01

    The integral monitored retrievable storage (I-MRS) proposal has major implications for geologic disposal. This paper reviews the positive and negative implications from the standpoint of a potential repository host state. Recommendations for improving the I-MRS proposal include: eliminate provisions restricting I-MRS backup role; add provisions to prevent I-MRS from becoming a permanent disposal facility; optimize reactor-to-I-MRS transportation system; further shift preclosure operations from repository to I-MRS; defer decision on rod consolidation; repeat the I-MRS site selection process; eliminate any potential linkage between I-MRS and nuclear weapons programs; and incorporate I-MRS in the repository siting program

  16. Considerations affecting deep-well disposal of tritium-bearing low-level aqueous waste from nuclear fuel reprocessing plants

    International Nuclear Information System (INIS)

    Trevorrow, L.E.; Warner, D.L.; Steindler, M.J.

    1977-03-01

    Present concepts of disposal of low-level aqueous wastes (LLAW) that contain much of the fission-product tritium from light water reactors involve dispersal to the atmosphere or to surface streams at fuel reprocessing plants. These concepts have been challenged in recent years. Deep-well injection of low-level aqueous wastes, an alternative to biospheric dispersal, is the subject of this presentation. Many factors must be considered in assessing its feasibility, including technology, costs, environmental impact, legal and regulatory constraints, and siting. Examination of these factors indicates that the technology of deep-well injection, extensively developed for other industrial wastes, would require little innovation before application to low-level aqueous wastes. Costs would be low, of the order of magnitude of 10 -4 mill/kWh. The environmental impact of normal deep-well disposal would be small, compared with dispersal to the atmosphere or to surface streams; abnormal operation would not be expected to produce catastrophic results. Geologically suitable sites are abundant in the U.S., but a well would best be co-located with the fuel-reprocessing plant where the LLAW is produced. Legal and regulatory constraints now being developed will be the most important determinants of the feasibility of applying the method

  17. Report on the disposal of radioactive wastes and spent fuel elements from Baden-Wuerttemberg

    International Nuclear Information System (INIS)

    2017-04-01

    The report on the disposal of radioactive wastes and spent fuel elements from Baden- Wuerttemberg covers the following issues: legal framework for the nuclear disposal; producer of spent fuels and radioactive wastes in Baden- Report on the disposal of radioactive wastes and spent fuel elements from Baden- Wuerttemberg; low- and medium-level radioactive wastes (non heat generating radioactive wastes); spent fuels and radioactive wastes from waste processing (heat generating radioactive wastes); final disposal.

  18. On a possibility to ground a reliable and safe disposing of a spent nuclear fuel from nuclear reactors RBMK in deep boreholes

    International Nuclear Information System (INIS)

    Kedrovskij, O.L.

    1998-01-01

    In order to isolate a spent nuclear fuel (SNF), it is proposed to dispose it, after 30 years keeping on the day surface, in boreholes of up to 4 km depth and 350-1020 mm diameter drilled in low permeable platform basement crystalline rocks, that allows one to localize SNF radionuclides till their full decay. It is shown that the method requires relatively low investments and enables the volume of a burial being increased during wastes income. Along with consideration and assessment of hydrodynamic, geological and hydrogeological parameters of a rock massive and rocks preferable for the new method, engineering solutions for the borehole design and hermetizing structure and assessments of the technogeneous influence on the environment are given. The questions are also considered of a possible shortening of the terms of keeping SNF in a surface storage before their burying, that enables one to decrease expenses for surface storage constructions and to promote the cleaning of the sphere of human habitation from the most active and dangerous wastes

  19. Criticality safety calculations for the nuclear waste disposal canisters

    International Nuclear Information System (INIS)

    Anttila, M.

    1996-12-01

    The criticality safety of the copper/iron canisters developed for the final disposal of the Finnish spent fuel has been studied with the MCNP4A code based on the Monte Carlo technique and with the fuel assembly burnup programs CASMO-HEX and CASMO-4. Two rather similar types of spent fuel disposal canisters have been studied. One canister type has been designed for hexagonal VVER-440 fuel assemblies used at the Loviisa nuclear power plant (IVO canister) and the other one for square BWR fuel bundles used at the Olkiluoto nuclear power plant (TVO canister). (10 refs.)

  20. Retrievability - a matter of public acceptance? Reflections on the public review of the proposed nuclear fuel waste disposal concept in Canada

    International Nuclear Information System (INIS)

    Riverin, G.

    2000-01-01

    Environmental assessment has been used as a planning tool in Canada for almost three decades. Public participation, one of its fundamental principles, is at the heart of environmental assessment in our country. To date, approximately 12 large projects related to nuclear energy have been the subject of public reviews by independent panels of experts appointed by the Government of Canada. These include: the development of uranium mines in Northern Saskatchewan; the construction and operation of two CANDU reactors in New-Brunswick, the second of which was never constructed; proposed uranium hexafluoride refineries in Ontario and Saskatchewan; expansion of a dry storage facility for nuclear spent fuel in Quebec; and decommissioning of uranium mine tailings areas in Ontario. All of the assessments mentioned above were conducted under the environmental assessment regimes of 1975 and 1984 that preceded the Canadian Environmental Assessment Act (1995). One of the public reviews of particular interest to this workshop is that of the proposed concept for deep geological disposal of nuclear fuel waste in Canada. This paper focuses exclusively on the public review of the Nuclear Fuel Waste Disposal Concept developed by Atomic Energy of Canada Limited (AECL), particularly as it relates to public acceptance of retrievability. The paper first describes the historical context in which AECL's concept was developed prior to the public review. It then briefly outlines the changes in the societal context that occurred between the time when decisions were made to proceed with the development of the concept in 1978 and the time when public hearings were held in 1996-1997 and the panel report was presented to the government in 1998. It also provides a short description of the concept itself. The paper then presents a discussion of the arguments used by the public in the panel review, arguments, which demonstrate a decrease in confidence in a concept lacking effective postclosure

  1. Nuclear chemistry research for the safe disposal of nuclear waste

    International Nuclear Information System (INIS)

    Fanghaenel, Thomas

    2011-01-01

    The safe disposal of high-level nuclear waste and spent nuclear fuel is of key importance for the future sustainable development of nuclear energy. Concepts foresee the isolation of the nuclear waste in deep geological formations. The long-term radiotoxicity of nuclear waste is dominated by plutonium and the minor actinides. Hence it is essential for the performance assessment of a nuclear waste disposal to understand the chemical behaviour of actinides in a repository system. The aqueous chemistry and thermodynamics of actinides is rather complex in particular due to their very rich redox chemistry. Recent results of our detailed study of the Plutonium and Neptunium redox - and complexation behaviour are presented and discussed. (author)

  2. Nuclear waste disposal site

    International Nuclear Information System (INIS)

    Mallory, C.W.; Watts, R.E.; Sanner, W.S. Jr.; Paladino, J.B.; Lilley, A.W.; Winston, S.J.; Stricklin, B.C.; Razor, J.E.

    1988-01-01

    This patent describes a disposal site for the disposal of toxic or radioactive waste, comprising: (a) a trench in the earth having a substantially flat bottom lined with a layer of solid, fluent, coarse, granular material having a high hydraulic conductivity for obstructing any capillary-type flow of ground water to the interior of the trench; (b) a non-rigid, radiation-blocking cap formed from a first layer of alluvium, a second layer of solid, fluent, coarse, granular material having a high hydraulic conductivity for blocking any capillary-type flow of water between the layer of alluvium and the rest of the cap, a layer of water-shedding silt for directing surface water away from the trench, and a layer of rip-rap over the silt layer for protecting the silt layer from erosion and for providing a radiation barrier; (c) a solidly-packed array of abutting modules of uniform size and shape disposed in the trench and under the cap for both encapsulating the wastes from water and for structurally supporting the cap, wherein each module in the array is slidable movable in the vertical direction in order to allow the array of modules to flexibly conform to variations in the shape of the flat trench bottom caused by seismic disturbances and to facilitate the recoverability of the modules; (d) a layer of solid, fluent, coarse, granular materials having a high hydraulic conductivity in the space between the side of the modules and the walls of the trench for obstructing any capillary-type flow of ground water to the interior of the trench; and (e) a drain and wherein the layer of silt is sloped to direct surface water flowing over the cap into the drain

  3. Is Yucca Mountain a long-term solution for disposing of US spent nuclear fuel and high-level radioactive waste?

    Science.gov (United States)

    Thorne, M C

    2012-06-01

    On 26 January 2012, the Blue Ribbon Commission on America's Nuclear Future released a report addressing, amongst other matters, options for the managing and disposal of high-level waste and spent fuel. The Blue Ribbon Commission was not chartered as a siting commission. Accordingly, it did not evaluate Yucca Mountain or any other location as a potential site for the storage or disposal of spent nuclear fuel and high-level waste. Nevertheless, if the Commission's recommendations are followed, it is clear that any future proposals to develop a repository at Yucca Mountain would require an extended period of consultation with local communities, tribes and the State of Nevada. Furthermore, there would be a need to develop generally applicable regulations for disposal of spent fuel and high-level radioactive waste, so that the Yucca Mountain site could be properly compared with alternative sites that would be expected to be identified in the initial phase of the site-selection process. Based on what is now known of the conditions existing at Yucca Mountain and the large number of safety, environmental and legal issues that have been raised in relation to the DOE Licence Application, it is suggested that it would be imprudent to include Yucca Mountain in a list of candidate sites for future evaluation in a consent-based process for site selection. Even if there were a desire at the local, tribal and state levels to act as hosts for such a repository, there would be enormous difficulties in attempting to develop an adequate post-closure safety case for such a facility, and in showing why this unsaturated environment should be preferred over other geological contexts that exist in the USA and that are more akin to those being studied and developed in other countries.

  4. Nuclear fuel cycle techniques

    International Nuclear Information System (INIS)

    Pecqueur, Michel; Taranger, Pierre

    1975-01-01

    The production of fuels for nuclear power plants involves five principal stages: prospecting of uranium deposits (on the ground, aerial, geochemical, geophysical, etc...); extraction and production of natural uranium from the deposits (U content of ores is not generally high and a chemical processing is necessary to obtain U concentrates); production of 235 U enriched uranium for plants utilizing this type of fuel (a description is given of the gaseous diffusion process widely used throughout the world and particularly in France); manufacture of suitable fuel elements for the different plants; reprocessing of spent fuels for the purpose of not only recovering the fissile materials but also disposing safely of the fission products and other wastes [fr

  5. Nuclear fuel element

    International Nuclear Information System (INIS)

    Penrose, R.T.; Thompson, J.R.

    1976-01-01

    A method of protecting the cladding of a nuclear fuel element from internal attack and a nuclear fuel element for use in the core of a nuclear reactor are disclosed. The nuclear fuel element has disposed therein an additive of a barium-containing material and the barium-containing material collects reactive gases through chemical reaction or adsorption at temperatures ranging from room temperature up to fuel element plenum temperatures. The additive is located in the plenum of the fuel element and preferably in the form of particles in a hollow container having a multiplicity of gas permeable openings in one portion of the container with the openings being of a size smaller than the size of the particles. The openings permit gases and liquids entering the plenum to contact the particles. The additive is comprised of elemental barium or a barium alloy containing one or more metals in addition to barium such as aluminum, zirconium, nickel, titanium and combinations thereof. 6 claims, 3 drawing figures

  6. The effects of the final disposal facility for spent nuclear fuel on regional economy; Kaeytetyn ydinpolttoaineen loppusijoituslaitoksen aluetaloudelliset vaikutukset

    Energy Technology Data Exchange (ETDEWEB)

    Laakso, S. [Seppo Laakso Urban Research (Finland)

    1999-03-01

    The study deals with the economic effects of the final disposal facility for spent nuclear fuel on the alternative location municipalities - Eurajoki, Kuhmo, Loviisa and Aeaenekoski - and their neighbouring areas (in Finland). The economic influence of the facility on industrials, employment, population, property markets, community structure and local public economics are analysed applying the approach of regional economics. The evaluation of the facility`s effects on employment is based on the input-output analysis. Both the direct and indirect effects of the construction and the functioning of the facility are taken into account in the analysis. According to the results the total increase in employment caused by the construction of the facility is about 350 persons annually, at national level. Some 150 persons of this are estimated to live in the wider region and 100-150 persons in the facility`s influence area consisting of the location municipality and neighbouring municipalities. This amount is reached at the top stage of construction (around the year 2018). At the production stage - after the year 2020 - the facility`s effects on employment will be concentrated significantly more on the location municipality and the rest of the influence area than on the rest of the country, compared with the construction stage. The estimated employment growth in the production stage is approximately 160 persons at national level of which 100-120 persons live in the candidate municipality and in the rest of the influence area. There is a direct link between local employment and population development. The growth of jobs attracts immigrants affecting the development of both the number and the structure of population. The facility`s effects on population development in the alternative location municipalities are analysed using comparative population forecasts based on demographic population projection methods. According to the results the job growth caused by the facility will

  7. Fuel and nuclear fuel cycle

    International Nuclear Information System (INIS)

    Prunier, C.

    1998-01-01

    The nuclear fuel is studied in detail, the best choice and why in relation with the type of reactor, the properties of the fuel cans, the choice of fuel materials. An important part is granted to the fuel assembly of PWR type reactor and the performances of nuclear fuels are tackled. The different subjects for research and development are discussed and this article ends with the particular situation of mixed oxide fuels ( materials, behavior, efficiency). (N.C.)

  8. The relationship between the Resource Conservation and Recovery Act and the storage and disposal of spent nuclear fuel and high-level waste

    International Nuclear Information System (INIS)

    Gertz, C.P.; Cloke, P.L.

    1993-01-01

    This paper addresses the potential applicability of the requirements of the Resource Conservation and Recovery Act (RCRA) to the disposal of spent commercial nuclear fuel and of high-level (vitrified) radioactive waste. The Atomic Energy Act of 1954, as amended, and the associated regulations issued by the US NRC provides many requirements that apply to these waste forms and largely, if not entirely, pre-empts the applicability of RCRA. The RCRA would apply only to the non-radioactive components of these wastes, and then only in respect to hazardous components. In view of these restrictions it becomes important to evaluate whether any components of spent fuel or high-level waste are toxic, as defined by the RCRA regulations. Present indications are that they are not and, hence, the US DOE is proceeding on the basis that these wastes and others that may be generated in the future are non-hazardous in respect to RCRA definitions

  9. Final disposal of nuclear waste. An investigated issue

    International Nuclear Information System (INIS)

    Palmu, J.; Nikula, A.

    1996-01-01

    Since 1978, the nuclear power companies have co-ordinated joint studies of nuclear waste disposal through the Nuclear Waste Commission of Finnish Power Companies. The studies are done primarily to gather basic data, with a view to implementing nuclear waste management in a safe, economical and timely way. The power companies' research, development and design work with regard to nuclear waste has been progressing according to the schedule set by the Government, and Finland has received international recognition for its advanced nuclear waste management programme. Last year, the nuclear power companies set up a joint company, Posiva Oy, to manage the final disposal of spent uranium fuel. (orig.)

  10. The nuclear disposal challenge

    International Nuclear Information System (INIS)

    2011-01-01

    In Germany, GNS Gesellschaft fuer Nuklear-Service mbH is in charge of all operations regarding the management of waste and residual materials from nuclear power plants. Jointly with its subsidiaries, GNS is reliably ensuring the safe packaging, treatment, transport and interim storage of these materials. Moreover, as the inventor and manufacturer of the CASTOR registered casks, GNS is the global leader in the field of casks for HLW. At its locations in Essen, Muelheim, Duisburg, Juelich, Karlsruhe, Ahaus and Gorleben, the GNS group has more than 550 employees and achieves a yearly turnover of more than 200 million Euro. (orig.)

  11. Regulation at nuclear fuel cycle

    International Nuclear Information System (INIS)

    2002-01-01

    This bulletin contains information about activities of the Nuclear Regulatory Authority of the Slovak Republic (UJD). In this leaflet the role of the UJD in regulation at nuclear fuel cycle is presented. The Nuclear Fuel Cycle (NFC) is a complex of activities linked with production of nuclear fuel for nuclear reactors as a source of energy used for production of electricity and heat, and of activities linked with spent nuclear fuel handling. Activities linked with nuclear fuel (NF) production, known as the Front-End of Nuclear Fuel Cycle, include (production of nuclear fuel from uranium as the most frequently used element). After discharging spent nuclear fuel (SNF) from nuclear reactor the activities follow linked with its storage, reprocessing and disposal known as the Back-End of Nuclear Fuel Cycle. Individual activity, which penetrates throughout the NFC, is transport of nuclear materials various forms during NF production and transport of NF and SNF. Nuclear reactors are installed in the Slovak Republic only in commercial nuclear power plants and the NFC is of the open type is imported from abroad and SNF is long-term supposed without reprocessing. The main mission of the area of NFC is supervision over: - assurance of nuclear safety throughout all NFC activities; - observance of provisions of the Treaty on Non-Proliferation of Nuclear Weapons during nuclear material handling; with an aim to prevent leakage of radioactive substances into environment (including deliberated danage of NFC sensitive facilities and misuse of nuclear materials to production of nuclear weapons. The UJD carries out this mission through: - assessment of safety documentation submitted by operators of nuclear installations at which nuclear material, NF and SNF is handled; - inspections concentrated on assurance of compliance of real conditions in NFC, i.e. storage and transport of NF and SNF; storage, transport and disposal of wastes from processing of SNF; with assumptions of the safety

  12. Advisory group meeting on safeguards related to final disposal of nuclear material in waste and spent fuel (AGM-660)

    International Nuclear Information System (INIS)

    1988-12-01

    The Advisory Group was asked to advise the Agency on the circumstances under which the Agency might logically implement Section 11 of INFCIRC/153, or the comparable Section 26c of INFCIRC/66/rev2, which provides for a determination that nuclear material is 'practicably irrecoverable', and that therefore safeguards could be terminated. This advice was sought, and in the paragraphs that follow is given, in two areas. One relates to 'waste', which the Group understands as referring to material which contains nuclear material that the State/facility operator believes has no economically recoverable value and for which no further use is foreseen. The other relates to spent fuel, which in some cases may be placed in geological 'permanent repositories'

  13. Programmer's guide for the CC3 computer models of the concept for disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    Dougan, K.D.

    1996-11-01

    Atomic Energy of Canada Limited (AECL) is assessing a concept for disposing of CANDU reactor fuel waste in a vault deep in plutonic rock of the Canadian Shield. A computer program called the Systems Variability Analysis Code (SYVAC) was developed as an analytical tool for the postclosure (long-term) assessment of the concept, and for environmental assessments of other systems. SYVAC3, the third generation of the code, is an executive program that directs repeated simulation of the disposal system, which is described by the CC3 (Canadian Concept, generation 3) model. The CC3 model is comprised of the disposal vault submodel, the local geosphere submodel and the biosphere submodel. The CC3 Proarammer's Guide describes the programming philosophy and programming conventions not covered in the project standards. The guide includes a description of the overall logic for the CC3 vault, geosphere, and biosphere submodels. Each of the CC3 submodels is also isolated from the other two submbdels to create autonomous or 'stand-alone' submodels. The techniques used to isolate a CC3 submodel, and in particular to determine the submodells input and output data interface, are described. Structure charts are provided for the CC3 model and stand-alone submodels. This guide is meant as a companion document to the CC3 User's Manual. This guide does not describe how to use the CC3 software. The user should consult the CC3 User's Manual to determine how to configure, compile, link, and run the CC3 source code, as well as how to modify the data in the input files. It is intended that the CC3 code version CC305 be executed with SYVAC3 version SV309 and the Modelling Algorithm Library (ML3) version ML303, both developed for the assessment of the concept. SYVAC3-CC3-ML3 (also referred to as 'SC3') can be run on any platform containing an ANSI FORTRAN 77 compliant compiler. Recommended hardware environments are specified in the CC3 User's Manual. (author)

  14. Preliminary evaluation of the impact and inter-generation risk transfers related to the release and disposal of radioactive waste from the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Tort, V.; Lochard, J.; Schneider, T.; Sugier, A.

    1997-12-01

    This report is an attempt to contribute to the complex issue of the decision-making in the field of radioactive waste management. Because of the complex and multidimensional nature of the distant future consequences of waste management options, their analysis implies the taking into considerations of various aggregated indicators which depend on the elapse of time during which the radionuclides remain in the environment and their local, regional or world-wide dispersion. This report is a preliminary work sponsored by IPSN mainly focused on the risk transfer dimension, inherent to waste disposal management. Its objective is to illustrate, using the French nuclear fuel cycle context, the relative impact of some simple waste management options, outlining particularly the issue of inter-generation risk transfer. Even though the selected six radionuclides are the most important, a complete assessment should include all the radionuclides contained in the waste, what is particularly important in case of underground waste disposal were both normal evolution scenarios and intrusion must be considered. The extreme alternatives, i.e. the total disposal or total release of the radionuclides are analyzed but realistic are the intermediate options, which should be thoroughly examined from the technical point of view. The analysis of intermediate management options could give an estimation of the most appropriate solution in an ALARA perspective

  15. Deep boreholes. An alternative for final disposal of spent nuclear fuel? Report from KASAM's question-and-answer session on 14-15 March 2007

    International Nuclear Information System (INIS)

    2009-03-01

    On 14-15 March 2007, KASAM held a hearing for the purpose of thoroughly examining deep boreholes as a method for the final disposal of spent nuclear fuel. Some of the questions that were raised were: What are the technical, geological and hydrological premises and possibilities? What are the risks from different viewpoints and what values underlie different views of the potential and suitability of deep boreholes? This report is a summary of the seminar. KASAM has made a selection of contributions and questions from the debate that took place on the basis of their relevance to the purpose of the seminar. The report generally follows the chronological lecture-and debate format of the seminar, but has been edited according to different issues rather than according to when different persons spoke. Chapter 2 describes a number of premises and criteria in the Environmental Code's and the Nuclear Activities Act's requirements on alternatives reporting. The chapter also contains a description of what the deep borehole concept entails and a discussion of the geoscientific premises. In addition, the chapter describes how different values can influence the choice of final disposal method. Chapters 3-6 describe and discuss technology and long-term safety, the viewpoints of the supervisory authorities on deep boreholes and safety philosophy via lectures followed by questions by KASAM's questioners and the audience. On the evening of 14 March, representatives of the seven parliamentary parties discussed their preparations and standpoints for an upcoming national debate on the final disposal of nuclear waste. This discussion is also reproduced in the report as Chapter 7. The main points from a concluding panel debate and discussion are presented in Chapter 8. In conclusion, Chapter 9 contains some reflections on various arguments proffered during the question-and-answer session, questions on which agreement seems to exist, and where there are differences of opinion. Speakers

  16. The impact of a final disposal facility for spent nuclear fuel on a municipality`s image; Tutkimus loppusijoituslaitoksen vaikutuksista kuntien imagoon

    Energy Technology Data Exchange (ETDEWEB)

    Kankaanpaeae, H; Haapavaara, L; Lampinen, T

    1999-02-01

    The study comprised on one hand a nationwide telephone interview (totally 800 interviews) aimed at mapping out the current image of possible host municipalities to a final disposal facility for spent nuclear fuel, and on the other hand some group interviews of people of another parish but of interest from the municipalities` point of view. The purpose of these group interviews was the same as that of the telephone interview, i.e. to find out what kind of an impact locating a final disposal facility of spent nuclear fuel in a certain municipality would have on the host municipality`s image. Because the groups interviewed were selected on different grounds the results of the interviews are not fully comparable. The most important result of the study is that the current attitude towards a final disposal facility for spent nuclear fuel is calm and collected and that the matter is often considered from the standpoint of an outsider. The issue is easily ignored, classified as a matter `which does not concern me`, provided that the facility will not be placed too near one`s own home. Among those interviewed the subject seemed not to be of any `great interest and did not arouse spontaneous feelings for or against`. There are, however, deeply rooted beliefs concerning the facility and quite strong negative and positive attitudes towards it. The facility itself and the associated decision-making procedure arouse many questions, which at present to a large extent are still unexpressed because the subject is considered so remote. It is, however, necessary to give concrete answers to the questions because this makes it possible for people to relate the issue to daily life. It is further important that things arousing fear and doubts also can be discussed because a silence in this respect only emphasizes their importance. The attitude towards the facility is varying. On one hand there are economic and technical factors: the probable economic benefit from it, the obligation to

  17. Disposal of nuclear wastes

    International Nuclear Information System (INIS)

    Albrecht, E.; Kuehn, K.

    1977-01-01

    Final storage of nuclear wastes in the salt mine at Asse is described. Until the end of 1976, all in all 73,000 containers with slightly radioactive wastes were deposited there within the framework of a test programme - the Asse pit is a pilot plant. Final storage of medium active waste was started in 1972. So far, about 1,150 barrels with medium active waste were deposited. Storage techniques applied, radiation exposure of the personnel and experience gained so far are reported on in this context. Final storage at Asse of highly active wastes developing decay heat is still in a preparatory stage, as here radiation as well as heat problems have to be mastered. Technical mining activities for the recoverable storage of highly-active, heat-developing wastes in the form of ceramic glasses are still in a planning phase, whereas advance work, e.g. cutting storage chambers out of seams 775 m thick have already begun. (HPH) [de

  18. Radioactive waste management decommissioning spent fuel storage. V. 3. Waste transport, handling and disposal spent fuel storage

    International Nuclear Information System (INIS)

    1985-01-01

    As part of the book entitled Radioactive waste management decommissioning spent fuel storage, vol. 3 dealts with waste transport, handling and disposal, spent fuel storage. Twelve articles are presented concerning the industrial aspects of nuclear waste management in France [fr

  19. Equity and nuclear waste disposal

    International Nuclear Information System (INIS)

    Shrader-Frechette, K.

    1994-01-01

    Following the recommendations of the US National Academy of Sciences and the mandates of the 1987 Nuclear Waste Policy Amendments Act, the US Department of Energy has proposed Yucca Mountain, Nevada as the site of the world's first permanent repository for high-level nuclear waste. The main justification for permanent disposal (as opposed to above-ground storage) is that it guarantees safety by means of waste isolation. This essay argues, however, that considerations of equity (safer for whom?) undercut the safety rationale. The article surveys some prima facie arguments for equity in the distribution of radwaste risks and then evaluates four objections that are based, respectively, on practicality, compensation for risks, scepticism about duties to future generations, and the uranium criterion. The conclusion is that, at least under existing regulations and policies, permanent waste disposal is highly questionable, in part, because it fails to distribute risk equitably or to compensate, in full, for this inequity

  20. Comparison between the KBS-3 method and the deep borehole for final disposal of spent nuclear fuel; Jaemfoerelse mellan KBS-3-metoden och deponering i djupa borrhaal foer slutligt omhaendertagande av anvaent kaernbraensle

    Energy Technology Data Exchange (ETDEWEB)

    Grundfelt, Bertil (Kemakta Konsult AB (Sweden))

    2010-09-15

    In this report a comparison is made between disposal of spent nuclear fuel according to the KBS-3 method with disposal in very deep boreholes. The objective has been to make a broad comparison between the two methods, and by doing so to pinpoint factors that distinguish them from each other. The ambition has been to make an as fair comparison as possible despite that the quality of the data of relevance is very different between the methods

  1. Critical review of nuclear fuel cycle

    International Nuclear Information System (INIS)

    Kuster, N.

    1996-01-01

    Transmutation of long-lived radionuclides is considered as an alternative to the in-depth disposal of spent nuclear fuel, in particular, on the final stage of the nuclear fuel cycle. The majority of conclusions is the result of the common work of the Karlsruhe FZK and the Commissariat on nuclear energy of France (CEA)

  2. Change in plan for installation of nuclear reactor in No.1 atomic powered vessel of Japan Atomic Energy Research Institute (change in purpose of use and in method for nuclear reactor installation and spent fuel disposal) (report)

    International Nuclear Information System (INIS)

    1987-01-01

    This report, compiled by the Nuclear Safety Commission to be submitted to the Prime Minister, deals with studies concerning some changes in the plan for the installation of a nuclear reactor in the No.1 atomic powered vessel to be constructed under the Japan Atomic Energy Research Institute (changes in the purpose of its use and in the methods for the nuclear reactor installation and spent fuel disposal). The conclusions of and procedures for the examination and evaluation are presented and then detailes of the studies are described. The study on the location requirements for the incidental land facilities at Sekinehama covers various conditions concerning the location, geology, earthquakes, meteorology, hydrology and social environment. The study on the safety design of the nuclear reactor facilities deals with the reactor, fuel handling facilities and other auxiliary facilities, as well as various land facilities to be constructed at Sekinehama including the reactor facilities and other facilities for fuel handling, waste disposal and protection and management of radioactive rays. Evaluation of possible radiation emission is shown and the accident analysis is also addressed. (Nogami, K.)

  3. The Canadian nuclear fuel waste management program

    International Nuclear Information System (INIS)

    Dixon, R.S.; Rosinger, E.L.J.

    1984-04-01

    This report, the fifth of a series of annual reports, reviews the progress that has been made in the research and development program for the safe management and disposal of Canada's nuclear fuel waste. The report summarizes activities over the past year in the following areas: public interaction; used fuel storage and transportation; immobilization of used fuel and fuel recycle waste; geoscience research related to deep underground disposal; environmental research; and environmental and safety assessment

  4. Quantitative mineralogy and preliminary pore-water chemistry of candidate buffer and backfill materials for a nuclear fuel waste disposal vault

    International Nuclear Information System (INIS)

    Quigley, R.M.

    1984-07-01

    The quantitative mineralogy of seven candidate buffer and backfill materials for a nuclear fuel waste disposal vault is presented. Two of the materials were coarse grained: one a blended very pure silica sand, and the other a crushed plagioclase-rich granite or granodiorite. Five materials were fine-grained soils containing abundant clay minerals. Of these, three were fairly pure, Cretaceous, ash-derived bentonites that contained up to 3 percent of soluble sulphates; one was a freshwater glacial clay containing 59 percent interlayered smectite-illite; and one was a crushed Paleozoic shale containing abundant illite and chlorite. The adsorbed cation regimes and the pore-water chemistry of the clays are discussed

  5. 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)

  6. The influence of the presence of sulphate on methanogenesis in the backfill of a Canadian nuclear fuel waste disposal vault: a laboratory study

    International Nuclear Information System (INIS)

    Sheppard, M.I.; Stroes-Gascoyne, S.; Motycka, M.; Haveman, S.A.

    1997-09-01

    Microbial gas production in the clay-based buffer and backfill materials of a nuclear waste disposal vault could produce gas bubbles or a separate gas phase, depending on quantities produced and the kinetics of the process. Gas production may affect the performance of the clay-based barriers. Results from previous laboratory experiments suggested that the presence of backfill or backfill clay prevented methane production in groundwater systems, likely because of inherently high sulphate concentrations in the clay. The work presented here shows that methane production in groundwater/clay systems is possible, but only at sulphate concentrations <35 mg/L. Sulphate concentrations in laboratory systems were lowered by the addition of Ba, and also by natural (microbiological or chemical) processes occurring over time (almost 700 d). Nutrient additions (acetate, diesel fuel) appeared to increase the magnitude of methane production but not necessarily speed the onset of methanogenesis. A high pH did not reduce or enhance methanogenesis, and the role of Fe in creating suitable conditions was not clear. Methane production rates in laboratory systems containing groundwater and backfill or backfill clay ranged from 0.1 to 0.125 mole%/d. In the presence of Ba-acetate, a rate as high as 0.7 mole%/d was observed. It is recommended that all microbial gas production experiments be continued for an adequate period of time, because of the considerable time required to develop suitable conditions for methanogenesis in laboratory systems. Methane production rates in water-limited clay environments, such as those expected in a nuclear fuel waste disposal vault, are needed as well as modelling of methane production for incorporation into vault performance optimization and safety assessments. (author)

  7. The influence of the presence of sulphate on methanogenesis in the backfill of a Canadian nuclear fuel waste disposal vault: a laboratory study

    Energy Technology Data Exchange (ETDEWEB)

    Sheppard, M I; Stroes-Gascoyne, S; Motycka, M; Haveman, S A

    1997-09-01

    Microbial gas production in the clay-based buffer and backfill materials of a nuclear waste disposal vault could produce gas bubbles or a separate gas phase, depending on quantities produced and the kinetics of the process. Gas production may affect the performance of the clay-based barriers. Results from previous laboratory experiments suggested that the presence of backfill or backfill clay prevented methane production in groundwater systems, likely because of inherently high sulphate concentrations in the clay. The work presented here shows that methane production in groundwater/clay systems is possible, but only at sulphate concentrations <35 mg/L. Sulphate concentrations in laboratory systems were lowered by the addition of Ba, and also by natural (microbiological or chemical) processes occurring over time (almost 700 d). Nutrient additions (acetate, diesel fuel) appeared to increase the magnitude of methane production but not necessarily speed the onset of methanogenesis. A high pH did not reduce or enhance methanogenesis, and the role of Fe in creating suitable conditions was not clear. Methane production rates in laboratory systems containing groundwater and backfill or backfill clay ranged from 0.1 to 0.125 mole%/d. In the presence of Ba-acetate, a rate as high as 0.7 mole%/d was observed. It is recommended that all microbial gas production experiments be continued for an adequate period of time, because of the considerable time required to develop suitable conditions for methanogenesis in laboratory systems. Methane production rates in water-limited clay environments, such as those expected in a nuclear fuel waste disposal vault, are needed as well as modelling of methane production for incorporation into vault performance optimization and safety assessments. (author) 30 refs., 6 tabs., 27 figs.

  8. Problems and prospects for nuclear waste disposal policy

    International Nuclear Information System (INIS)

    Herzik, E.B.; Mushkatel, A.H.

    1996-01-01

    This book is a collection of articles examining legal, organizational, and public-interest issues involving the transportation, storage, treatment, and disposal of radioactive wastes. The introductions examines the unresolved issues of nuclear-waste policy-making in the USA and then presents essays covering the disposal of commercial power plant fuel, low level radioactive wastes, the by-products of nuclear weapons production, and the challenges of transporting radiological materials

  9. Nuclear fuel

    International Nuclear Information System (INIS)

    Quinauk, J.P.

    1990-01-01

    Since 1985, Fragema has been marketing and selling the Advanced Fuel Assemby AFA whose main features are its zircaloy grids and removable top and bottom nozzles. It is this product, which exists for several different fuel assembly arrays and heights, that will be employed in the reactors at Daya Bay. Fragema employs gadolinium as the consumable poison to enable highperformance fuel management. More recently, the company has supplied fuel assemblies of the mixed-oxide(MOX) and enriched reprocessed uranium type. The reliability level of the fuel sold by Fragema is one of the highest in the world, thanks in particular to the excellence of the quality assurance and quality control programs that have been implemented at all stages of its design and manufacture

  10. Nuclear waste disposal: Technology and environmental hazards

    International Nuclear Information System (INIS)

    Hare, F.K.; Aikin, A.M.

    1984-01-01

    The authors have arrived at what appears to be a comforting conclusion--that the ultimate disposal of nuclear wastes should be technically feasible and very safe. They find that the environment and health impacts will be negligible in the short-term, being due to the steps that precede the emplacement of the wastes in the repository. Disposal itself, once achieved, offers no short-term threat--unless an unforseen catastrophe of very low probability occurs. The risks appear negligible by comparison with those associated with earlier stages of the fuel cycle. Ultimately -- millinnia hence -- a slow leaching of radionuclides to the surface might begin. But it would be so slow that great dilution of each nuclide will occur. This phase is likely to be researched somewhere in the period 100,000 to 1,000,000 years hence

  11. Evolution of repository and waste package designs for Yucca Mountain disposal system for spent nuclear fuel and high-level radioactive waste

    International Nuclear Information System (INIS)

    Rechard, Rob P.; Voegele, Michael D.

    2014-01-01

    This paper summarizes the evolution of the engineered barrier design for the proposed Yucca Mountain disposal system. Initially, the underground facility used a fairly standard panel and drift layout excavated mostly by drilling and blasting. By 1993, the layout of the underground facility was changed to accommodate construction by a tunnel boring machine. Placement of the repository in unsaturated zone permitted an extended period without backfilling; placement of the waste package in an open drift permitted use of much larger, and thus hotter packages. Hence in 1994, the underground facility design switched from floor emplacement of waste in small, single walled stainless steel or nickel alloy containers to in-drift emplacement of waste in large, double-walled containers. By 2000, the outer layer was a high nickel alloy for corrosion resistance and the inner layer was stainless steel for structural strength. Use of large packages facilitated receipt and disposal of high volumes of spent nuclear fuel. In addition, in-drift package placement saved excavation costs. Options considered for in-drift emplacement included different heat loads and use of backfill. To avoid dripping on the package during the thermal period and the possibility of localized corrosion, titanium drip shields were added for the disposal drifts by 2000. In addition, a handling canister, sealed at the reactor to eliminate further handling of bare fuel assemblies, was evaluated and eventually adopted in 2006. Finally, staged development of the underground layout was adopted to more readily adjust to changes in waste forms and Congressional funding. - Highlights: • Progression of events associated with repository design to accommodate tunnel boring machine and in-drift waste package emplacement are discussed. • Change in container design from small, single-layered stainless steel vessel to large, two-layered nickel alloy vessel is discussed. • The addition of drip shield to limit the

  12. Judgement of properties and function of concrete in connection with final disposal of nuclear fuel wastes in rock

    International Nuclear Information System (INIS)

    Bergstroem, S.G.; Fagerlund, G.; Romben, L.

    1977-06-01

    This report deals with the possibility of using concrete in conjuction with the permanent storage of nuclear fuel waste in rock storage facilities. The emphasis has been placed on properties such as strength and tightness and how these may be affected by internal and external causes of destruction during a filling stage of approximately 100 years and during the final storage stage of 1 000 - 100 000 years. It is established that spontaneous structural changes, which lead to a certain increase in porosity, cannot be precluded during the filling stage and uring the final storage stage. It is deemed possible to avoid cracking during the manufacture and during the filling stage if the concrete is kept moist. The risk for cracking during the final storage stage is difficult to assess. Attempts are made to estimate the tightness of aged concrete during the various stages. The tightness during the final storage stage is difficult to assess due to the fact that the scope of the cracking cannot be estimated. Chemical attacks during the filling stage are deemed to be small and can be repaired. The risk for destruction due to radioactive radiation is extremely small. Reinforcement, if any, can be protected during the filling stage on condition that the concrete is kep saturated but all reinforcement will be destroyed during the final storage stage. By way of conclusion, a number of general views on the choice of concrete and work methods are provided. (author)

  13. Decision nearing on final disposal of spent fuel in Finland

    International Nuclear Information System (INIS)

    Vira, J.

    2000-01-01

    The programme for final disposal of spent fuel from Finnish nuclear power plants is entering into important phase: in the year 2000 the Finnish Government is expected to decide whether the proposal made by Posiva Oy on the spent fuel disposal is in line with the overall good of society. Associated with the decision is also Posiva's proposal on siting the disposal facility at Olkiluoto in Eurajoki municipality on the western coast of Finland. An important document underlying Posiva's application for this principle decision is the report of the environmental impact assessment, which was completed in 1999. Safety considerations play an important role in the application. New assessments have, therefore, been made on both the operational and long-term safety as well as on safety of spent fuel transportation. (author)

  14. Final disposal of spent fuel in the Finnish bedrock

    International Nuclear Information System (INIS)

    1992-12-01

    Teollisuuden Voima Oy (TVO) is preparing for the final disposal of spent nuclear fuel from the Olkiluoto nuclear power plant (TVO-I and TVO-II reactors). According to present estimates, a total of 1840 tU of spent fuel will be accumulated during the 40-year lifetime of the power plant. An interim storage facility for spent fuel (TVO-KPA Store) has operated at Olkiluoto since 1987. The spent fuel will be held in storage for several decades before it is shipped to the repository site. Both train and road transportation are possible. The spent fuel will be encapsulated in composite copper and steel canisters (ACP Canister) in a facility that will be build above the ground on the site where the repository is located. The repository will be constructed at the depth of several hundreds of meters in the bedrock. In 1987 five areas were selected for preliminary site investigations. The safety analysis (TVO-92) that was carried out shows that the proposed safety criteria would be met at each of the candidate sites. In future expected conditions there would never be significant releases of radioactive substances to the biosphere. The site investigations will be continued in the period 1993 to 2000. In parallel, a R and D programme will be devoted to the safety and technology of final disposal. The site for final disposal will be selected in the year 2000 with the aim of having the capability to start the disposal operations in 2020

  15. Consultation Report. Consultation under the Environmental Act sixth chapter 4 paragraph for interim storage, encapsulation and disposal of spent nuclear fuel; Samraadsredogoerelse. Samraad enligt miljoebalkens 6:e kapitel 4:e paragraf avseende mellanlagring, inkapsling och slutfoervaring av anvaent kaernbraensle

    Energy Technology Data Exchange (ETDEWEB)

    2010-09-15

    This consultation report is an appendix to the Environmental Impact Assessment (EIA) which in turn is an appendix to SKB's application under the Environmental Code for the continued operation of CLAB (Central interim storage for spent Nuclear Fuel, located on the Simpevarp Peninsula in Oskarshamn municipality), to build the encapsulation plant and operate it integrated with CLAB and to construct and operate the disposal facility in Soederviken at Forsmark in Oesthammar municipality, and SKB's application for a license under the Nuclear Activities Act to construct and operate the disposal facility at Forsmark. The aim of the consultation report is to give an overall picture of the consultations.

  16. Deep boreholes. An alternative for final disposal of spent nuclear fuel? Report from KASAM's question-and-answer session on 14-15 March 2007

    Energy Technology Data Exchange (ETDEWEB)

    2009-03-15

    On 14-15 March 2007, KASAM held a hearing for the purpose of thoroughly examining deep boreholes as a method for the final disposal of spent nuclear fuel. Some of the questions that were raised were: What are the technical, geological and hydrological premises and possibilities? What are the risks from different viewpoints and what values underlie different views of the potential and suitability of deep boreholes? This report is a summary of the seminar. KASAM has made a selection of contributions and questions from the debate that took place on the basis of their relevance to the purpose of the seminar. The report generally follows the chronological lecture-and debate format of the seminar, but has been edited according to different issues rather than according to when different persons spoke. Chapter 2 describes a number of premises and criteria in the Environmental Code's and the Nuclear Activities Act's requirements on alternatives reporting. The chapter also contains a description of what the deep borehole concept entails and a discussion of the geoscientific premises. In addition, the chapter describes how different values can influence the choice of final disposal method. Chapters 3-6 describe and discuss technology and long-term safety, the viewpoints of the supervisory authorities on deep boreholes and safety philosophy via lectures followed by questions by KASAM's questioners and the audience. On the evening of 14 March, representatives of the seven parliamentary parties discussed their preparations and standpoints for an upcoming national debate on the final disposal of nuclear waste. This discussion is also reproduced in the report as Chapter 7. The main points from a concluding panel debate and discussion are presented in Chapter 8. In conclusion, Chapter 9 contains some reflections on various arguments proffered during the question-and-answer session, questions on which agreement seems to exist, and where there are differences of

  17. Nuclear fuel element

    International Nuclear Information System (INIS)

    Iwano, Yoshihiko.

    1993-01-01

    Microfine cracks having a depth of less than 10% of a pipe thickness are disposed radially from a central axis each at an interval of less than 100 micron over the entire inner circumferential surface of a zirconium alloy fuel cladding tube. For manufacturing such a nuclear fuel element, the inside of the cladding tube is at first filled with an electrolyte solution of potassium chloride. Then, electrolysis is conducted using the cladding tube as an anode and the electrolyte solution as a cathode, and the inner surface of the cladding tube with a zirconium dioxide layer having a predetermined thickness. Subsequently, the cladding tube is laid on a smooth steel plate and lightly compressed by other smooth steel plate to form microfine cracks in the zirconium dioxide layer on the inner surface of the cladding tube. Such a compressing operation is continuously applied to the cladding tube while rotating the cladding tube. This can inhibit progress of cracks on the inner surface of the cladding tube, thereby enabling to prevent failure of the cladding tube even if a pellet/cladding tube mechanical interaction is applied. Accordingly, reliability of the nuclear fuel elements is improved. (I.N.)

  18. Method of manufacturing nuclear fuel pellet

    International Nuclear Information System (INIS)

    Oguma, Masaomi; Masuda, Hiroshi; Hirai, Mutsumi; Tanabe, Isami; Yuda, Ryoichi.

    1989-01-01

    In a method of manufacturing nuclear fuel pellets by compression molding an oxide powder of nuclear fuel material followed by sintering, a metal nuclear material is mixed with an oxide powder of the nuclear fuel material. As the metal nuclear fuel material, whisker or wire-like fine wire or granules of metal uranium can be used effectively. As a result, a fuel pellet in which the metal nuclear fuel is disposed in a network-like manner can be obtained. The pellet shows a great effect of preventing thermal stress destruction of pellets upon increase of fuel rod power as compared with conventional pellets. Further, the metal nuclear fuel material acts as an oxygen getter to suppress the increase of O/M ratio of the pellets. Further, it is possible to reduce the swelling of pellet at high burn-up degree. (T.M.)

  19. 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.

  20. Fuel containing vessel for transporting nuclear fuel

    International Nuclear Information System (INIS)

    Yoshizawa, Hiroyasu; Shimizu, Fukuzo; Tanaka, Nobuyuki.

    1996-01-01

    A shock absorbing mechanism is disposed on an inner bottom of a vessel main body. The shock absorbing mechanism comprises a shock absorbing member disposed on the upper surface of a bottom wall, an annular metal plate disposed on the upper surface of the shock absorbing member and an annular spacer disposed on the upper surface of the metal plate. The shock absorbing member is made of a material such as of wood, lead, metal honeycomb or a metal mesh, which plastically deforms when applied with load higher than a predetermined level, and is formed in a square block-like form covering the upper surface of the bottom wall. The spacer is made of a thin soft material such as tetrafluoroethylene, and is formed in such a shape as capable of preventing direct contact of the lower end of the cylindrical member in a lower tie plate of nuclear fuels with the metal portion. This can ensure integrity of nuclear fuels even when they fall from a high place upon an assumed dropping accident. (I.N.)

  1. Concept for Underground Disposal of Nuclear Waste

    Science.gov (United States)

    Bowyer, J. M.

    1987-01-01

    Packaged waste placed in empty oil-shale mines. Concept for disposal of nuclear waste economically synergistic with earlier proposal concerning backfilling of oil-shale mines. New disposal concept superior to earlier schemes for disposal in hard-rock and salt mines because less uncertainty about ability of oil-shale mine to contain waste safely for millenium.

  2. Nuclear waste management: storage and disposal aspects

    International Nuclear Information System (INIS)

    Patterson, B.D.; Dave, S.A.; O'Connell, W.J.

    1980-01-01

    Long-term disposal of nuclear wastes must resolve difficulties arising chiefly from the potential for contamination of the environment and the risk of misuse. Alternatives available for storage and disposal of wastes are examined in this overview paper. Guidelines and criteria which may govern in the development of methods of disposal are discussed

  3. The effects of the final disposal facility for spent nuclear fuel on regional and municipal economy assessment of socio economical impacts

    International Nuclear Information System (INIS)

    Laakso, S.; Kuisma, H.; Kilpelaeinen, P.; Kostiainen, E.

    2007-12-01

    The aim of this study is to give an up-to-date assessment of the effects the construction of the final disposal facility for spent nuclear fuel in Eurajoki, based on latest knowledge. The disposal facility's effects on employment, population, housing construction, community structure and economy are estimated in the municipality of Eurajoki and in the wider region under the influence of the facility. The time-span of the report reaches from 2001 to the early 2020's when the facility will be in operation. The investment in research and construction of the disposal facility during the years 2004-2020 will be all together approximately 290 million euros. The estimation for the overall effect on national employment during the years 2001-2020 is circa 6 800 manyears, of which 4 200 man-years are from direct effects and 2 600 from indirect effects. The direct employment effects of the project will be at its highest approximately 325 man-year per year in 2020. The direct effect on employment during the operational period is estimated to be circa 130 man-years per year, of which the share of regular employees of Posiva is slightly over 100 man-years. At its highest, about 45 man-years per year of the total effect on employment (direct + indirect effects) will be directed to Eurajoki municipality. During the operational phase the share of Eurajoki is estimated to be circa 30 man-years per year. For the whole region, the effect of the disposal facility on employment will be significant, at its height in 2020, approximately 220 man-years per year. The disposal facility will also have an effect on the size and the structure of the population due to changes in employment and jobs. The estimation for the cumulative effect on the growth of the population caused by the facility is 80 more inhabitants in Eurajoki by 2020, which corresponds to 1,4 % of the municipality's current population. The growth of the population brought about by the facility in the whole region is estimated

  4. Spent nuclear fuel storage vessel

    International Nuclear Information System (INIS)

    Watanabe, Yoshio; Kashiwagi, Eisuke; Sekikawa, Tsutomu.

    1997-01-01

    Containing tubes for containing spent nuclear fuels are arranged vertically in a chamber. Heat releasing fins are disposed horizontal to the outer circumference of the containing tubes for rectifying cooling air and promoting cooling of the containing tubes. Louvers and evaporation sides of heat pipes are disposed at a predetermined distance in the chamber. Cooling air flows from an air introduction port to the inside of the chamber and takes heat from the containing tubes incorporated with heat generating spent nuclear fuels, rising its temperature and flows off to an air exhaustion exit. The direction for the rectification plate of the louver is downward from a horizontal position while facing to the air exhaustion port. Since the evaporation sides of the heat pipes are disposed in the inside of the chamber and the condensation side of the heat pipes is disposed to the outside of the chamber, the thermal energy can be recovered from the containing tubes incorporated with spent nuclear fuels and utilized. (I.N.)

  5. Social dimensions of nuclear waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Grunwald, Armin [Karlsruhe Institute of Technology, Karlsruhe (Germany). Inst. for Technology Assessment and Systems Analysis

    2015-07-01

    Nuclear waste disposal is a two-faceted challenge: a scientific and technological endeavour, on the one hand, and confronted with social dimensions, on the other. In this paper I will sketch the respective social dimensions and will give a plea for interdisciplinary research approaches. Relevant social dimensions of nuclear waste disposal are concerning safety standards, the disposal 'philosophy', the process of determining the disposal site, and the operation of a waste disposal facility. Overall, cross-cutting issues of justice, responsibility, and fairness are of major importance in all of these fields.

  6. Social dimensions of nuclear waste disposal

    International Nuclear Information System (INIS)

    Grunwald, Armin

    2015-01-01

    Nuclear waste disposal is a two-faceted challenge: a scientific and technological endeavour, on the one hand, and confronted with social dimensions, on the other. In this paper I will sketch the respective social dimensions and will give a plea for interdisciplinary research approaches. Relevant social dimensions of nuclear waste disposal are concerning safety standards, the disposal 'philosophy', the process of determining the disposal site, and the operation of a waste disposal facility. Overall, cross-cutting issues of justice, responsibility, and fairness are of major importance in all of these fields.

  7. Disposal of fissionable material from dismantled nuclear weapons

    International Nuclear Information System (INIS)

    Taylor, J.J.

    1991-01-01

    The reduction in tensions between the United States and the Soviet Union has improved the prospects for nuclear disarmament, making it more likely that significant numbers of nuclear warheads will be dismantled by the United States and USSR in the foreseeable future. Thus, the question becomes more urgent as to the disposition of the weapons materials, highly enriched uranium and plutonium. It is timely, therefore, to develop specific plans for such disposal. The overall process for disposal of weapons materials by the burnup option involves the following steps: (1) removing the weapons material from the warheads, (2) converting the material to a fuel form suitable for power reactors, (3) burning it up as a power reactor fuel, and (4) removing the spent fuel and placing it in a permanent repository. This paper examines these four steps with the purpose of answering the following questions. What facilities would be appropriate for the disposal process? Do they need to be dedicated facilities, or could industrial facilities be used? What is the present projection of the economics of the burnup process, both the capital investment and the operating costs? How does one assure that fissionable materials will not be diverted to military use during the disposal process? Is the spent fuel remaining from the burnup process proliferation resistant? Would the disposal of spent fuel add an additional burden to the spent fuel permanent repository? The suggested answers are those of the author and do not represent a position by the Electric Power Research Institute

  8. The legislation of nuclear disposal. Text booklet with an introduction

    International Nuclear Information System (INIS)

    Smeddinck, Ulrich

    2014-01-01

    The book on the legislation of nuclear waste disposal covers the following issues: Part A: Introduction in the site selection law. Part B: Set of regulations: Constitutional law of the Federal Republic of Germany (extract), Guideline 2011/70 EURATOM on the responsible and safe disposal of spent fuel elements, common agreement on the safety of spent fuel treatment and on the safety of radioactive waste conditioning, law on search and selection of final repository site for heat generating radioactive wastes (site selection law), law on the civil use of nuclear energy and the protection against its hazards (Atomic Law AtG), federal mining act (BBergG), law on environmental impact assessment (UVPG), Law on supplementary regulations and legal remedies in environmental matters according EU guideline 2003/35EG, law on the construction of a Federal authority for nuclear disposal (BfkEEG), regulation on the protection against ionizing radiation hazards (Strahlenschutzverordnung), regulation on the transport of radioactive wastes or spent fuel elements. Regulation on the commissioning processes of facilities according paragraph 7 Atomic law, regulation on the definition of a development freeze for site protection for a final disposal, regulation on the warranty of nuclear safety and radiation protection, implementing rule for the nuclear safety warranty, regulation on the advance financing for the construction of Federal facilities for safeguarding and final disposal of radioactive wastes. Cost regulation for the Atomic Law.

  9. Nuclear waste disposal educational forum

    International Nuclear Information System (INIS)

    1982-01-01

    In keeping with a mandate from the US Congress to provide opportunities for consumer education and information and to seek consumer input on national issues, the Department of Energy's Office of Consumer Affairs held a three-hour educational forum on the proposed nuclear waste disposal legislation. Nearly one hundred representatives of consumer, public interest, civic and environmental organizations were invited to attend. Consumer affairs professionals of utility companies across the country were also invited to attend the forum. The following six papers were presented: historical perspectives; status of legislation (Senate); status of legislation (House of Representatives); impact on the legislation on electric utilities; impact of the legislation on consumers; implementing the legislation. All six papers have been abstracted and indexed for the Energy Data Base

  10. The Canadian nuclear fuel waste management program

    International Nuclear Information System (INIS)

    Dixon, R.S.

    1984-12-01

    The Canadian Nuclear Fuel Waste Management Program involves research into the storage and transportation of used nuclear fuel, immobilization of fuel waste, and deep geological disposal of the immobilized waste. The program is now in the fourth year of a ten-year generic research and development phase. The objective of this phase of the program is to assess the safety and environmental aspects of the deep underground disposal of immobilized fuel waste in plutonic rock. The objectives of the research for each component of the program and the progress made to the end of 1983 are described in this report

  11. The disposal of Canada's nuclear fuel waste: a study of postclosure safety of in-room emplacement of used CANDU fuel in copper containers in permeable plutonic rock. Volume 3: geosphere model

    International Nuclear Information System (INIS)

    Stanchell, F.W.; Davison, C.C.; Melnyk, T.W.; Scheier, N.W.; Chan, T.

    1996-06-01

    This report discusses the approach we used to develop a model of the 3-D network of transport pathways through the geosphere from the location of a nuclear fuel waste disposal vault at a depth of 500 m in a hypothetical permeable plutonic rock mass. The transport pathways correspond to the pathways of advective groundwater movement through this permeable rock from the disposal vault to discharge areas at groundsurface. In this analysis we assumed the permeability of the region of rock immediately surrounding the waste emplacement areas of the disposal vault was considerably higher than the permeability used in the geosphere model for the EIS case study. We also assumed the porosity of the rock could fall within the range 10 -3 to 10 -5 to represent the range of effects by alternative conceptual models of flow through fracture networks in the rock. Advection by the groundwater flow field in the rock surrounding the disposal vault entirely controls the rate and direction of transport from the vault in this geosphere model. The hydrogeological environment we assumed for this geosphere model is entirely hypothetical, unlike the model we developed for the EIS case study which was a conservative, yet realistic, representation of the hydrogeological conditions encountered at the site of our Underground Research Laboratory in the Whiteshell Research Area. We used the same geometry of rock structures for this model as we used in the geosphere model for the EIS case study but we assigned hydrogeologic properties to the various rock domains of the model that result in relatively rapid groundwater flow from the depth of the disposal vault to surface discharge areas. This report desribes the modelling and sensitivity analyses we performed with the MOTIF finite element model to develop the GEONET transport network for this hypothetical geosphere situation. The geosphere model accounts for the effects of natural geothermal heat and vault-induced heat on transport pathways

  12. The politics of nuclear-waste disposal

    International Nuclear Information System (INIS)

    Tarricone, P.

    1994-01-01

    After 72 days of public hearings and testimony from more than 100 witnesses, the first commission of its kind in the US found that politics--not science and engineering--led to the selection of Martinsville, Ill. as the host site for a nuclear-waste-disposal facility. This article examines how the plan to dispose of nuclear waste in Martinsville ultimately unraveled

  13. Update to Assessment of Direct Disposal in Unsaturated Tuff of Spent Nuclear Fuel and High-Level Waste Owned by U.S. Department of Energy

    Energy Technology Data Exchange (ETDEWEB)

    P. D. Wheatley (INEEL POC); R. P. Rechard (SNL)

    1998-09-01

    The overall purpose of this study is to provide information and guidance to the Office of Environmental Management of the U.S. Department of Energy (DOE) about the level of characterization necessary to dispose of DOE-owned spent nuclear fuel (SNF). The disposal option modeled was codisposal of DOE SNF with defense high-level waste (DHLW). A specific goal was to demonstrate the influence of DOE SNF, expected to be minor, in a predominately commercial repository using modeling conditions similar to those currently assumed by the Yucca Mountain Project (YMP). A performance assessment (PA) was chosen as the method of analysis. The performance metric for this analysis (referred to as the 1997 PA) was dose to an individual; the time period of interest was 100,000 yr. Results indicated that cumulative releases of 99Tc and 237Np (primary contributors to human dose) from commercial SNF exceed those of DOE SNF both on a per MTHM and per package basis. Thus, if commercial SNF can meet regulatory performance criteria for dose to an individual, then the DOE SNF can also meet the criteria. This result is due in large part to lower burnup of the DOE SNF (less time for irradiation) and to the DOE SNF's small percentage of the total activity (1.5%) and mass (3.8%) of waste in the potential repository. Consistent with the analyses performed for the YMP, the 1997 PA assumed all cladding as failed, which also contributed to the relatively poor performance of commercial SNF compared to DOE SNF.

  14. Update to Assessment of Direct Disposal in Unsaturated Tuff of Spent Nuclear Fuel and High-Level Waste Owned by U.S. Department of Energy

    International Nuclear Information System (INIS)

    Wheatley, P.D.; Rechard, R.P.

    1998-01-01

    The overall purpose of this study is to provide information and guidance to the Office of Environmental Management of the U.S. Department of Energy (DOE) about the level of characterization necessary to dispose of DOE-owned spent nuclear fuel (SNF). The disposal option modeled was codisposal of DOE SNF with defense high-level waste (DHLW). A specific goal was to demonstrate the influence of DOE SNF, expected to be minor, in a predominately commercial repository using modeling conditions similar to those currently assumed by the Yucca Mountain Project (YMP). A performance assessment (PA) was chosen as the method of analysis. The performance metric for this analysis (referred to as the 1997 PA) was dose to an individual; the time period of interest was 100,000 yr. Results indicated that cumulative releases of 99Tc and 237Np (primary contributors to human dose) from commercial SNF exceed those of DOE SNF both on a per MTHM and per package basis. Thus, if commercial SNF can meet regulatory performance criteria for dose to an individual, then the DOE SNF can also meet the criteria. This result is due in large part to lower burnup of the DOE SNF (less time for irradiation) and to the DOE SNF's small percentage of the total activity (1.5%) and mass (3.8%) of waste in the potential repository. Consistent with the analyses performed for the YMP, the 1997 PA assumed all cladding as failed, which also contributed to the relatively poor performance of commercial SNF compared to DOE SNF

  15. Nuclear fuel preheating system

    International Nuclear Information System (INIS)

    Andrea, C.

    1975-01-01

    A nuclear reactor new fuel handling system which conveys new fuel from a fuel preparation room into the reactor containment boundary is described. The handling system is provided with a fuel preheating station which is adaptd to heat the new fuel to reactor refueling temperatures in such a way that the fuel is heated from the top down so that fuel element cladding failure due to thermal expansions is avoided. (U.S.)

  16. Ontario Hydro's plan for used nuclear fuel

    International Nuclear Information System (INIS)

    Stevens-Guille, P.D.; Howes, H.A.; Freire-Canosa, J.

    1992-01-01

    A comprehensive plan for the management of used nuclear fuel has been published by Ontario Hydro. In this paper current practices are discussed and actions leading to disposal in a repository are outlined. Extended storage options are discussed should disposal be delayed

  17. Spent fuel disposal problem in Bulgaria

    Energy Technology Data Exchange (ETDEWEB)

    Milanov, M; Stefanova, I [Bylgarska Akademiya na Naukite, Sofia (Bulgaria). Inst. za Yadrena Izsledvaniya i Yadrena Energetika

    1994-12-31

    The internationally agreed basic safety principles and criteria for spent fuel (SF) and high level waste (HLW) disposal are outlined. In the framework of these principles the specific problems of Bulgaria described in the `National Concept for Radioactive Waste Management and Disposal in Republic of Bulgaria` are discussed. The possible alternatives for spent fuel management are: (1) sending the spent fuel for disposal in other country; (2) once-through cycle and (3) closed fuel cycle. A mixed solution of the problem is implemented in Bulgaria. According to the agreement between Bulgaria and former Soviet Union a part of the spent fuel has been returned to Russia. The once-through and closed-fuel cycle are also considered. The projected cumulated amount of spent fuel is estimated for two cases: (1) the six units of Kozloduy NPP are in operation till the end of their lifetime (3300 tHM) and (2) low estimate (2700 tHM) - only units 5 and 6 are operated till the end of their lifetime. The reprocessing of the total amount of 3300 tHM will lead to the production of about 370 m{sup 3} vitrified high level wastes. Together with the HLW about 1850 m{sup 3} cladding hulls and 7800 m{sup 3} intermediate-level wastes will be generated, which should be disposed off in deep geological repository. The total production of radioactive waste in once-through cycle is 181 000 m{sup 3}, and in closed cycle - 190 000 m{sup 3}. Geological investigations are performed resulting in categorization of the territory of the country based on geological, geotechnical and hydrogeological conditions. This will facilitate the choice of the most suitable location for deep geological repository. 7 figs., 11 refs.

  18. Unsaturated flow modeling in performance assessments for the Yucca Mountain disposal system for spent nuclear fuel and high-level radioactive waste

    International Nuclear Information System (INIS)

    Rechard, Rob P.; Birkholzer, Jens T.; Wu, Yu-Shu; Stein, Joshua S.; Houseworth, James E.

    2014-01-01

    This paper summarizes the progression of modeling efforts of infiltration, percolation, and seepage conducted between 1984 and 2008 to evaluate feasibility, viability, and assess compliance of a repository in the unsaturated zone for spent nuclear fuel and high-level radioactive waste at Yucca Mountain, Nevada. Scientific understanding of infiltration in a desert environment, unsaturated percolation flux in fractures and matrix of the volcanic tuff, and seepage into an open drift in a thermally perturbed environment was initially lacking in 1984. As understanding of the Yucca Mountain disposal system increased through site characterization and in situ testing, modeling of infiltration, percolation, and seepage evolved from simple assumptions in a single model in 1984 to three modeling modules each based on several detailed process models in 2008. Uncertainty in percolation flux through Yucca Mountain was usually important in explaining the observed uncertainty in performance measures:cumulative release in assessments prior to 1995 and individual dose, thereafter. - Highlights: • Progression of modeling of infiltration, percolation, and seepage conducted is described for a geological repository at Yucca Mountain. • Progression from 1-D in single equivalent to 3-D model of percolation in dual permeability continuum is described. • Introduction of an infiltration boundary condition in 1998 and the refinement for evaluating uncertainty for the license application is described. • Introduction of a seepage module that included calibration to in-site measurements and separating uncertainty and variability is described

  19. Waste degradation and mobilization in performance assessments for the Yucca Mountain disposal system for spent nuclear fuel and high-level radioactive waste

    International Nuclear Information System (INIS)

    Rechard, Rob P.; Stockman, Christine T.

    2014-01-01

    This paper summarizes modeling of waste degradation and mobilization in performance assessments (PAs) conducted between 1984 and 2008 to evaluate feasibility, viability, and assess compliance of a repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain in southern Nevada. As understanding of the Yucca Mountain disposal system increased, the waste degradation module, or succinctly called the source-term, evolved from initial assumptions in 1984 to results based on process modeling in 2008. In early PAs, waste degradation had significant influence on calculated behavior but as the robustness of the waste container was increased and modeling of the container degradation improved, waste degradation had much less influence in later PAs. The variation of dissolved concentrations of radionuclides progressed from simple probability distributions in early PAs to functions dependent upon water chemistry in later PAs. Also, transport modeling of radionuclides in the waste, container, and invert were added in 1995; and, colloid-facilitated transport of radionuclides was added in 1998. - Highlights: • Progression of modeling of waste degradation in performance assessments is discussed for the proposed repository at Yucca Mountain. • Progression of evaluating dissolved concentrations of radionuclides in the source-term is discussed. • Radionuclide transport modeling in the waste, container, and invert in 1995 and thereafter is discussed. • Colloid-facilitated transport in the waste, container, and invert in 1998 and thereafter is discussed

  20. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Terrain and ecosystems development modelling in the biosphere assessment BSA-2012

    International Nuclear Information System (INIS)

    2013-12-01

    This report is one of the four supporting reports for the three main biosphere reports in the safety case for the disposal of spent nuclear fuel at Olkiluoto, 'TURVA-2012'. The focus of this report is to detail the scenario analysis of terrain and ecosystems development at the Olkiluoto repository site within a time frame of 10 000 years, whereas the input data to this modelling is detailed in the Data Basis report. The results are used further especially in the surface and near-surface hydrological modelling and in the biosphere radionuclide transport and dose modelling, both part of the biosphere assessment 'BSA-2012' feeding into the safety case. Based on the results of the 18 cases simulated in the scenario analysis, it can be outlined that the most significant differences in respect of the dose implications of the repository arise from the inputs and settings affecting the rate of coastline retreat (i.e. land uplift and sea level) and determining whether there are croplands or not in the area. (orig.)

  1. Romanian nuclear fuel program

    International Nuclear Information System (INIS)

    Budan, O.

    1999-01-01

    The paper presents and comments the policy adopted in Romania for the production of CANDU-6 nuclear fuel before and after 1990. The CANDU-6 nuclear fuel manufacturing started in Romania in December 1983. Neither AECL nor any Canadian nuclear fuel manufacturer were involved in the Romanian industrial nuclear fuel production before 1990. After January 1990, the new created Romanian Electricity Authority (RENEL) assumed the responsibility for the Romanian Nuclear Power Program. It was RENEL's decision to stop, in June 1990, the nuclear fuel production at the Institute for Nuclear Power Reactors (IRNE) Pitesti. This decision was justified by the Canadian specialists team findings, revealed during a general, but well enough technically founded analysis performed at IRNE in the spring of 1990. All fuel manufactured before June 1990 was quarantined as it was considered of suspect quality. By that time more than 31,000 fuel bundles had already been manufactured. This fuel was stored for subsequent assessment. The paper explains the reasons which provoked this decision. The paper also presents the strategy adopted by RENEL after 1990 regarding the Romanian Nuclear Fuel Program. After a complex program done by Romanian and Canadian partners, in November 1994, AECL issued a temporary certification for the Romanian nuclear fuel plant. During the demonstration manufacturing run, as an essential milestone for the qualification of the Romanian fuel supplier for CANDU-6 reactors, 202 fuel bundles were produced. Of these fuel bundles, 66 were part of the Cernavoda NGS Unit 1 first fuel load (the balance was supplied by Zircatec Precision Industries Inc. ZPI). The industrial nuclear fuel fabrication re-started in Romania in January 1995 under AECL's periodical monitoring. In December 1995, AECL issued a permanent certificate, stating the Romanian nuclear fuel plant as a qualified and authorised CANDU-6 fuel supplier. The re-loading of the Cernavoda NGS Unit 1 started in the middle

  2. Nuclear fuel lease accounting

    International Nuclear Information System (INIS)

    Danielson, A.H.

    1986-01-01

    The subject of nuclear fuel lease accounting is a controversial one that has received much attention over the years. This has occurred during a period when increasing numbers of utilities, seeking alternatives to traditional financing methods, have turned to leasing their nuclear fuel inventories. The purpose of this paper is to examine the current accounting treatment of nuclear fuel leases as prescribed by the Financial Accounting Standards Board (FASB) and the Federal Energy Regulatory Commission's (FERC's) Uniform System of Accounts. Cost accounting for leased nuclear fuel during the fuel cycle is also discussed

  3. Quivers For Special Fuel Rods-Disposal Of Special Fuel Rods In CASTOR V Casks

    International Nuclear Information System (INIS)

    Bannani, Amin; Cebula, Wojciech; Buchmuller, Olga; Huggenberg, Roland; Helmut Kuhl

    2015-01-01

    While GNS casks of the CASTOR family are a suitable means to transfer fuel assemblies (FA) from the NPP to an interim dry storage site, Germanys phase-out of nuclear energy has triggered the demand for an additional solution to dispose of special fuel rods (SFR), normally remaining in the fuel pond until the final shutdown of the NPP. SFR are fuel rods that had to be removed from fuel assemblies mainly due to their special condition, e. g. damages in the cladding of the fuel rods which may have occurred during reactor operations. SFR are usually stored in the spent fuel pond after they are removed from the FA. The quiver for special fuel rods features a robust yet simple design, with a high mechanical stability, a reliable leak-tightness and large safety margins for future requirements on safety analysis. The quiver for special fuel rods can be easily adapted to a large variety of different damaged fuel rods and tailored to the specific need of the customer. The quiver for special fuel rods is adaptable e.g. in length and diameter for use in other types of transport and storage casks and is applicable in other countries as well. The overall concept presented here is a first of its kind solution for the disposal of SFRs via Castor V-casks. This provides an important precondition in achieving the status 'free from nuclear fuel' of the shut down German NPPs

  4. Quivers For Special Fuel Rods-Disposal Of Special Fuel Rods In CASTOR V Casks

    Energy Technology Data Exchange (ETDEWEB)

    Bannani, Amin; Cebula, Wojciech; Buchmuller, Olga; Huggenberg, Roland [GNS, Essen (Germany); Helmut Kuhl [WTI, Julich (Germany)

    2015-05-15

    While GNS casks of the CASTOR family are a suitable means to transfer fuel assemblies (FA) from the NPP to an interim dry storage site, Germanys phase-out of nuclear energy has triggered the demand for an additional solution to dispose of special fuel rods (SFR), normally remaining in the fuel pond until the final shutdown of the NPP. SFR are fuel rods that had to be removed from fuel assemblies mainly due to their special condition, e. g. damages in the cladding of the fuel rods which may have occurred during reactor operations. SFR are usually stored in the spent fuel pond after they are removed from the FA. The quiver for special fuel rods features a robust yet simple design, with a high mechanical stability, a reliable leak-tightness and large safety margins for future requirements on safety analysis. The quiver for special fuel rods can be easily adapted to a large variety of different damaged fuel rods and tailored to the specific need of the customer. The quiver for special fuel rods is adaptable e.g. in length and diameter for use in other types of transport and storage casks and is applicable in other countries as well. The overall concept presented here is a first of its kind solution for the disposal of SFRs via Castor V-casks. This provides an important precondition in achieving the status 'free from nuclear fuel' of the shut down German NPPs.

  5. Overview of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Knief, R.A.

    1978-01-01

    The nuclear fuel cycle is substantially more complicated than the energy production cycles of conventional fuels because of the very low abundance of uranium 235, the presence of radioactivity, the potential for producing fissile nuclides from irradiation, and the risk that fissile materials will be used for nuclear weapons. These factors add enrichment, recycling, spent fuel storage, and safeguards to the cycle, besides making the conventional steps of exploration, mining, processing, use, waste disposal, and transportation more difficult

  6. Nuclear waste disposal: technology and environmental hazards

    International Nuclear Information System (INIS)

    Hare, F.K.; Aikin, A.M.

    1980-01-01

    The subject is discussed under the headings: introduction; the nature and origin of wastes (fuel cycles; character of wastes; mining and milling operations; middle stages; irradiated fuel; reprocessing (waste generation); reactor wastes); disposal techniques and disposal of reprocessing wastes; siting of repositories; potential environmental impacts (impacts after emplacement in a rock repository; catastrophic effects; dispersion processes (by migrating ground water); thermal effects; future security; environmental survey, monitoring and modelling); conclusion. (U.K.)

  7. Rack for nuclear fuel elements

    International Nuclear Information System (INIS)

    Rubinstein, H.J.; Gordon, C.B.; Robison, A.; Clark, P.M.

    1977-01-01

    Disclosed is a rack for storing spent nuclear fuel elements in which a plurality of aligned rows of upright enclosures of generally square cross-sectional areas contain vertically disposed spent fuel elements. Each fuel element is supported at the lower end thereof by a respective support that rests on the floor of the spent fuel pool for a nuclear power plant. An open rack frame is employed as an upright support for the enclosures containing the spent fuel elements. Legs at the lower corners of the frame rest on the floor of the pool to support the frame. In one exemplary embodiment, the support for the fuel element is in the form of a base on which a fuel element rests and the base is supported by legs. In another exemplary embodiment, each fuel element is supported on the pool floor by a self-adjusting support in the form of a base on which a fuel element rests and the base rests on a ball or swivel joint for self-alignment. The lower four corners of the frame are supported by legs adjustable in height for leveling the frame. Each adjustable frame leg is in the form of a base resting on the pool floor and the base supports a threaded post. The threaded post adjustably engages a threaded column on which rests the lower end of the frame. 16 claims, 14 figures

  8. DFN Modeling for the Safety Case of the Final Disposal of Spent Nuclear Fuel in Olkiluoto, Finland

    Science.gov (United States)

    Vanhanarkaus, O.

    2017-12-01

    Olkiluoto Island is a site in SW Finland chosen to host a deep geological repository for high-level nuclear waste generated by nuclear power plants of power companies TVO and Fortum. Posiva, a nuclear waste management organization, submitted a construction license application for the Olkiluoto repository to the Finnish government in 2012. A key component of the license application was an integrated geological, hydrological and biological description of the Olkiluoto site. After the safety case was reviewed in 2015 by the Radiation and Nuclear Safety Authority in Finland, Posiva was granted a construction license. Posiva is now preparing an updated safety case for the operating license application to be submitted in 2022, and an update of the discrete fracture network (DFN) model used for site characterization is part of that. The first step describing and modelling the network of fractures in the Olkiluoto bedrock was DFN model version 1 (2009), which presented an initial understanding of the relationships between rock fracturing and geology at the site and identified the important primary controls on fracturing. DFN model version 2 (2012) utilized new subsurface data from additional drillholes, tunnels and excavated underground facilities in ONKALO to better understand spatial variability of the geological controls on geological and hydrogeological fracture properties. DFN version 2 connected fracture geometric and hydraulic properties to distinct tectonic domains and to larger-scale hydraulically conductive fault zones. In the version 2 DFN model, geological and hydrogeological models were developed along separate parallel tracks. The version 3 (2017) DFN model for the Olkiluoto site integrates geological and hydrogeological elements into a single consistent model used for geological, rock mechanical, hydrogeological and hydrogeochemical studies. New elements in the version 3 DFN model include a stochastic description of fractures within Brittle Fault Zones (BFZ

  9. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    Hindle, E.D.

    1981-01-01

    An array of rods comprising zirconium alloy sheathed nuclear fuel pellets assembled to form a fuel element for a pressurised water reactor is claimed. The helium gas pressure within each rod differs substantially from that of its closest neighbours

  10. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    Hindle, E.D.

    1984-01-01

    The fuel elements for a pressurised water reactor comprise arrays of rods of zirconium alloy sheathed nuclear fuel pellets. The helium gas pressure within each rod differs substantially from that of its closest neighbours

  11. Nuclear fuel accounting

    International Nuclear Information System (INIS)

    Aisch, D.E.

    1977-01-01

    After a nuclear power plant has started commercial operation the actual nuclear fuel costs have to be demonstrated in the rate making procedure. For this purpose an accounting system has to be developed which comprises the following features: 1) All costs associated with nuclear fuel shall be correctly recorded; 2) it shall be sufficiently flexible to cover also deviations from proposed core loading patterns; 3) it shall be applicable to different fuel cycle schemes. (orig./RW) [de

  12. The disposal of Canada's nuclear fuel waste: a study of postclosure safety of in-room emplacement of used CANDU fuel in copper containers in permeable plutonic rock. Volume 2: vault model

    International Nuclear Information System (INIS)

    Johnson, L.H.; LeNeveu, D.M.; King, F.; Shoesmith, D.W.; Kolar, M.; Oscarson, D.W.; Sunder, S.; Onofrei, C.; Crosthwaite, J.L.

    1996-06-01

    A study has been undertaken to evaluate the design and long-term performance of a nuclear fuel waste disposal vault based on a concept of in-room emplacement of copper containers at a depth of 500 m in plutonic rock in the Canadian Shield. The containers, each with 72 used CANDU fuel bundles, would be surrounded by clay-based buffer and backfill materials in an array of parallel rooms, with the excavation boundary assumed to have an excavation-disturbed zone (EDZ) with a higher permeability than the surrounding rock. In the anoxic conditions of deep rock of the Canadian Shield, the copper containers are expected to survive for >10 6 a. Thus container manufacturing defects, which are assumed to affect approximately 1 in 5000 containers, would be the only potential source of radionuclide release in the vault. The vault model is a computer code that simulates the release of radionuclides that would occur upon contact of the used fuel with groundwater, the diffusive transport of these radionuclides through the defect in the container shell and the surrounding buffer, and their dispersive and convective transport through the backfill and EDZ into the surrounding rock. The vault model uses a computationally efficient boundary integral model (BIM) that simulates radionuclide mass transport in the engineered barrier system as a point source (representing the defective container) that releases radionuclides into concentric cylinders, that represent the buffer, backfill and EDZ. A 3-dimensional finite-element model is used to verify the accuracy of the BIM. The results obtained in the present study indicates the effectiveness of a design using in-room emplacement of long-lived containers in providing a safe disposal system even under permeable geosphere conditions. (author). refs., tabs., figs

  13. The nuclear fuel cycle

    International Nuclear Information System (INIS)

    1998-05-01

    After a short introduction about nuclear power in the world, fission physics and the French nuclear power plants, this brochure describes in a digest way the different steps of the nuclear fuel cycle: uranium prospecting, mining activity, processing of uranium ores and production of uranium concentrates (yellow cake), uranium chemistry (conversion of the yellow cake into uranium hexafluoride), fabrication of nuclear fuels, use of fuels, reprocessing of spent fuels (uranium, plutonium and fission products), recycling of energetic materials, and storage of radioactive wastes. (J.S.)

  14. Recent developments in the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Wunderer, A.

    1984-01-01

    There is a description of the present situation in each individual area of the nuclear fuel cycle. Further topics are: risk and safety factors and emissions from the fuel cycle, availability and disruptions, waste disposal and the storage of radioactive waste. (UA) [de

  15. A design concept of underground facilities for the deep geologic disposal of spent fuel

    International Nuclear Information System (INIS)

    Lee, Jong Youl; Choi, Heui Joo; Choi, Jong Won; Hahn, Pil Soo

    2005-01-01

    Spent nuclear fuel from nuclear power plants can be disposed in the underground repository. In this paper, a concept of Korean Reference HLW disposal System (KRS-1) design is presented. Though no site for the underground repository has been specified in Korea, but a generic site with granitic rock is considered for reference spent fuel repository design. To implement the concept, design requirements such as spent fuel characteristics and capacity of the repository and design principles were established. Then, based on these requirements and principles, a concept of the disposal process, the facilities and the layout of the repository was developed

  16. Lessons from nature. The behaviour of technical and natural barriers in the geological disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Marcos, N.

    2002-01-01

    This work deals with the study of the long-term performance of materials and elements involved in the near- and far-field of an underground nuclear waste repository. Materials and elements occurring in nature are similar, or at least analogous, to the materials and elements manufactured or processed by man. Also, natural processes may be similar to those envisaged as occurring in a nuclear waste repository. This similarity makes it possible to study the behaviour of those materials in nature and to compare it with the behaviour of the manufactured materials to be used in a repository. As many materials and elements have been in the natural environment for long time periods (thousands to million of years), the data obtained can be extrapolated to estimate the future evolution of similar components in a nuclear waste repository. Thinking by analogy is the process of comparison, with those materials, elements and environments used to perform the studies that allow the comparison to be regarded as natural analogues. The Hyrkkoelae U-Cu mineralisation (SW Finland) was studied as an analogue to the behaviour of copper canisters in crystalline bedrock. This analogue could also address the interaction between copper corrosion products and uranium. Copper sulphides are shown to retain up to 25% of uranium as U (IV) even if oxidizing conditions prevail. Furthermore, uranium was observed in smectite (main component of bentonite) associated with native copper and cuprite, which constitutes an analogue to the behaviour of the repository near-field materials in a natural oxidizing environment. In addition to the Hyrkkoelae analogue, the issue of irreversible sorption or uranium immobilization is also addressed, in the studies of the boulder rock near Haemeenlinna. The behaviour of U, Th, and rare earth elements (REE) as analogues to the long-lived actinides is also evaluated in groundwater and rock samples at Olkiluoto (SW Finland). U and Th were shown to be released more easily

  17. The status of nuclear fuel cycle system analysis for the development of advanced nuclear fuel cycles

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Won Il; Kim, Seong Ki; Lee, Hyo Jik; Chang, Hong Rae; Kwon, Eun Ha; Lee, Yoon Hee; Gao, Fanxing [KAERI, Daejeon (Korea, Republic of)

    2011-11-15

    The system analysis has been used with different system and objectives in various fields. In the nuclear field, the system can be applied from uranium mining to spent fuel reprocessing or disposal which is called the nuclear fuel cycle. The analysis of nuclear fuel cycle can be guideline for development of advanced fuel cycle through integrating and evaluating the technologies. For this purpose, objective approach is essential and modeling and simulation can be useful. In this report, several methods which can be applicable for development of advanced nuclear fuel cycle, such as TRL, simulation and trade analysis were explained with case study

  18. Disposal of high-activity nuclear wastes

    International Nuclear Information System (INIS)

    Hamilton, E.I.

    1983-01-01

    A discussion is presented on the deep sea ocean disposal for high-activity nuclear wastes. The following topics are covered: effect of ionizing radiation on marine ecosystems; pathways by which radionuclides are transferred to man from the marine environment; information about releases of radioactivity to the sea; radiological protection; storage and disposal of radioactive wastes and information needs. (U.K.)

  19. TVO-92 safety analysis of spent fuel disposal

    International Nuclear Information System (INIS)

    Vieno, T.; Hautojaervi, A.; Koskinen, L.; Nordman, H.

    1993-08-01

    The spent fuel from the TVO I and TVO II reactors at the Olkiluoto nuclear power plant is planned to be disposed in a repository constructed at a depth of about 500 meters in crystalline bedrock. Teollisuuden Voima Oy (TVO) has carried out preliminary site investigations for spent fuel disposal between 1987 and 1992 at five areas in Finland (Olkiluoto, Kivetty, Romuvaara, Syyry and Veitsivaara). The Safety analysis of the disposal system is presented in the report. Spent fuel will be encapsulated in composite copper-steel canisters. The canister design (ACP canister) consists of an inner container of steel as a load-bearing element and an outer container of oxygen-free copper to provide a shield against corrosion. In the repository the canisters will be emplaced in vertical holes drilled in the floors of horizontal deposition tunnels. The annulus between the canister and the rock is filled with compacted bentonite. The results of the safety analysis attest that the planned disposal system fulfils the safety requirements. Suitable places for the repository can be found at each of the five investigation sites

  20. Applications of polymer coatings for the fabrication of copper-based containers for the ultimate disposal of Canada's spent nuclear fuel

    Science.gov (United States)

    Mortley, Aba

    Oxygen-free, phosphorous doped copper containers have been proposed for the storage of the used nuclear fuel bundles as a part of Canada's multi-barrier, adaptive phased management procedure for long term storage of spent nuclear fuel bundles. The spent nuclear fuel disposal system proposed for Canada has been engineered based on the multi-barrier approach intended to minimize the risk that the radioactive materials enter the biosphere. Copper is known to be susceptible to corrosion and it is thought that the simultaneous exposure to aggressive ionizing radiation field and residual heat produced by the spent nuclear fuel and the surrounding groundwater would all challenge the container's integrity. The goal of the present work is to reduce the impact of corrosion in the early stages of emplacement with the addition of a protective coating. Specifically, castor oil based polyurethanes were assessed as coatings and their ability to act as an additional physical barrier in the multi-barrier system mentioned previously. The novelty of this work stems from the use of a naturally derived non-petroleum based material in the form of castor oil as the polyol component. Two types of castor oil polyurethanes were investigated, one based on an aliphatic hexamethylene diisocyanate (HMDI), and the other based on an aromatic 2,4-toluene diisocyanate (TDI). Radiation and saturation tests were conducted using varying conditions. Mixed field ionizing radiation was provided by a SLOWPOKE-2 pool-type nuclear research reactor, up to accumulated doses of 6 MGy at dose rates of 37 kGy h-1 and 55.5 kGy h-1. Weight gain immersion studies, at temperatures of 25° C, 50° C, 70° C, were used to determine the mass uptake of several different solutions. The solutions utilized in the present work included hydrochloric acids of varying pHs, distilled water, and buffered solutions, which simulated chloride and sulphide rich calcium-sodium bicarbonate waters. After being exposed to radiation and

  1. Nuclear fuel element

    International Nuclear Information System (INIS)

    1974-01-01

    A nuclear fuel element for use in the core of a nuclear reactor is disclosed. A heat conducting fission product retaining metal liner of a refractory metal is incorporated in the fuel element between the cladding and the nuclear fuel to inhibit mechanical interaction between the nuclear fuel and the cladding, to isolate fission products and nuclear fuel impurities from contacting the cladding, and to improve the axial thermal peaking gradient along the length of the fuel rod. The metal liner can be in the form of a tube or hollow cylindrical column, a foil of single or multiple layers in the shape of a hollow cylindrical column, or a coating on the internal surface of the cladding. Preferred refractory metal materials are molybdenum, tungsten, rhenium, niobium and alloys of the foregoing metals

  2. Nuclear fuel element

    International Nuclear Information System (INIS)

    Thompson, J.R.; Rowland, T.C.

    1976-01-01

    A nuclear fuel element for use in the core of a nuclear reactor is disclosed. A heat conducting, fission product retaining metal liner of a refractory metal is incorporated in the fuel element between the cladding and the nuclear fuel to inhibit mechanical interaction between the nuclear fuel and the cladding, to isolate fission products and nuclear fuel impurities from contacting the cladding and to improve the axial thermal peaking gradient along the length of the fuel rod. The metal liner can be in the form of a tube or hollow cylindrical column, a foil of single or multiple layers in the shape of a hollow cylindrical column, or a coating on the internal surface of the cladding. Preferred refractory metal materials are molybdenum, tungsten, rhenium, niobium and alloys of the foregoing metals

  3. Heat transfer enhancement for spent nuclear fuel assembly disposal packages using metallic void fillers: A prevention technique for solidification shrinkage-induced interfacial gaps

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yongsoo, E-mail: yspark@alum.mit.edu; McKrell, Thomas J.; Driscoll, Michael J.

    2017-06-15

    This study considers replacing the externally accessible void spaces inside a disposal package containing a spent nuclear fuel assembly (SNFA) with high heat conducting metal to increase the effective thermal conductivity of the package and simplify the heat transfer mechanism inside the package by reducing it to a conduction dominant problem. The focus of the study is on preventing the gaps adjacent to the walls of the package components, produced by solidification shrinkage of poured liquid metal. We approached the problem by providing a temporary coating layer on the components to avoid direct build-up of thick metal oxides on their surface to promote metallic bonding at the interfaces under a non-inert environment. Laboratory scale experiments without SNFA were performed with Zn coated low carbon steel canisters and Zamak-3 void filler under two different filling temperature conditions – below and above the melting point of Zn (designated BMP and AMP respectively). Gap formation was successfully prevented in both cases while we confirmed an open gap in a control experiment, which used an uncoated canister. Minor growth of Al-Fe intermetallic phases was observed at the canister/filler interface of the sample produced under the BMP condition while their growth was significant and showed irregularly distributed morphology in the sample produced under the AMP condition, which has a potential to mitigate excessive residual stresses caused by shrinkage prevention. A procedure for the full-scale application was specified based on the results. - Highlights: •A void filling technique is introduced to enhance SNFA package heat transfer. •The technique is demonstrated via experiments using the Fe-Al-Zn system. •A procedure for the full scale application is proposed based on the results.

  4. Assessment of the long-term risks of inadvertent human intrusion into a proposed Canadian nuclear fuel waste disposal vault in deep plutonic rock -revision 1

    International Nuclear Information System (INIS)

    Wuschke, D.M.

    1996-04-01

    Canada has conducted an extensive research program on a concept of safe disposal of nuclear fuel wastes deep In plutonic rock of the Canadian Shield. An essential goal of this program has been to develop and demonstrate a methodology to evaluate the performance of the facility against safety criteria established by Canada's regulatory agency, the Atomic Energy Control Board. These criteria are expressed in terms of risk, where risk is defined as the sum, over all significant scenarios, of the product of the probability of the scenario, the magnitude of the resultant dose, and the probability of a health effect per unit dose. This report describes the methodology developed to assess the long-term risk from inadvertent human intrusion into such a facility, and the results of its application to the proposed facility. Four intrusion scenarios were analysed, all initiated by a drilling operation. These scenarios are exposure of a member of the drilling crew, of a technologist conducting a core examination, of a construction worker and of a resident. The consequence of each scenario was estimated using standard computer codes for environmental pathways analysis and radiation dosimetry. For comparison with the risk criterion, an estimate of the probability of each scenario is also required. An event-tree methodology was used to estimate these probabilities. The estimated risks from these intrusion scenarios are several orders of magnitude below the established risk criterion. The event-tree methodology has the advantages of explicity displaying the assumptions made, of permitting easy testing of the sensitivity of the risk estimates to assumptions, and of combining technical and sociological information. (author). 53 refs., 8 tabs., 2 figs

  5. Assessment of the long-term risks of inadvertent human intrusion into a proposed Canadian nuclear fuel waste disposal vault in deep plutonic rock -revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Wuschke, D M

    1996-04-01

    Canada has conducted an extensive research program on a concept of safe disposal of nuclear fuel wastes deep In plutonic rock of the Canadian Shield. An essential goal of this program has been to develop and demonstrate a methodology to evaluate the performance of the facility against safety criteria established by Canada`s regulatory agency, the Atomic Energy Control Board. These criteria are expressed in terms of risk, where risk is defined as the sum, over all significant scenarios, of the product of the probability of the scenario, the magnitude of the resultant dose, and the probability of a health effect per unit dose. This report describes the methodology developed to assess the long-term risk from inadvertent human intrusion into such a facility, and the results of its application to the proposed facility. Four intrusion scenarios were analysed, all initiated by a drilling operation. These scenarios are exposure of a member of the drilling crew, of a technologist conducting a core examination, of a construction worker and of a resident. The consequence of each scenario was estimated using standard computer codes for environmental pathways analysis and radiation dosimetry. For comparison with the risk criterion, an estimate of the probability of each scenario is also required. An event-tree methodology was used to estimate these probabilities. The estimated risks from these intrusion scenarios are several orders of magnitude below the established risk criterion. The event-tree methodology has the advantages of explicity displaying the assumptions made, of permitting easy testing of the sensitivity of the risk estimates to assumptions, and of combining technical and sociological information. (author). 53 refs., 8 tabs., 2 figs.

  6. Assessment of the long-term risk of a meteorite impact on a hypothetical Canadian nuclear fuel waste disposal vault deep in plutonic rock

    International Nuclear Information System (INIS)

    Wuschke, D.M.; Whitaker, S.H.; Goodwin, B.W.; Rasmussen, L.R.

    1995-06-01

    This report describes an assessment of the long-term radiological risk to an individual of the critical group that would result from a meteorite impact on a hypothetical reference disposal vault for used fuel, located 500 m below the Earth's surface. The purpose of the assessment was to determine if this radiological risk could exceed or approach the AECB risk criterion. (author). 47 refs., 5 tabs., 6 figs

  7. Device for separating, purifying and recovering nuclear fuel material, impurities and materials from impurity-containing nuclear fuel materials or nuclear fuel containing material

    International Nuclear Information System (INIS)

    Sato, Ryuichi; Kamei, Yoshinobu; Watanabe, Tsuneo; Tanaka, Shigeru.

    1988-01-01

    Purpose: To separate, purify and recover nuclear fuel materials, impurities and materials with no formation of liquid wastes. Constitution: Oxidizing atmosphere gases are introduced from both ends of a heating furnace. Vessels containing impurity-containing nuclear fuel substances or nuclear fuel substance-containing material are continuously disposed movably from one end to the other of the heating furnace. Then, impurity oxides or material oxides selectively evaporated from the impurity-containing nuclear fuel substances or nuclear fuel substance-containing materials are entrained in the oxidizing atmosphere gas and the gases are led out externally from a discharge port opened at the intermediate portion of the heating furnace, filters are disposed to the exit to solidify and capture the nuclear fuel substances and traps are disposed behind the filters to solidify and capture the oxides by spontaneous air cooling or water cooling. (Sekiya, K.)

  8. Development of geological disposal system for spent fuels and high-level radioactive wastes in Korea

    International Nuclear Information System (INIS)

    Choi, Heui Joo; Lee, Jong Youl; Choi, Jong Won

    2013-01-01

    Two different kinds of nuclear power plants produce a substantial amount of spent fuel annually in Korea. According to the current projection, it is expected that around 60,000 MtU of spent fuel will be produced from 36 PWR and APR reactors and 4 CANDU reactors by the end of 2089. In 2006, KAERI proposed a conceptual design of a geological disposal system (called KRS, Korean Reference disposal System for spent fuel) for PWR and CANDU spent fuel, as a product of a 4-year research project from 2003 to 2006. The major result of the research was that it was feasible to construct a direct disposal system for 20,000 MtU of PWR spent fuels and 16,000 MtU of CANDU spent fuel in the Korean peninsula. Recently, KAERI and MEST launched a project to develop an advanced fuel cycle based on the pyroprocessing of PWR spent fuel to reduce the amount of HLW and reuse the valuable fissile material in PWR spent fuel. Thus, KAERI has developed a geological disposal system for high-level waste from the pyroprocessing of PWR spent fuel since 2007. However, since no decision was made for the CANDU spent fuel, KAERI improved the disposal density of KRS by introducing several improved concepts for the disposal canister. In this paper, the geological disposal systems developed so far are briefly outlined. The amount and characteristics of spent fuel and HLW, 4 kinds of disposal canisters, the characteristics of a buffer with domestic Ca-bentonite, and the results of a thermal design of deposition holes and disposal tunnels are described. The different disposal systems are compared in terms of their disposal density.

  9. DEVELOPMENT OF GEOLOGICAL DISPOSAL SYSTEMS FOR SPENT FUELS AND HIGH-LEVEL RADIOACTIVE WASTES IN KOREA

    Directory of Open Access Journals (Sweden)

    HEUI-JOO CHOI

    2013-02-01

    Full Text Available Two different kinds of nuclear power plants produce a substantial amount of spent fuel annually in Korea. According to the current projection, it is expected that around 60,000 MtU of spent fuel will be produced from 36 PWR and APR reactors and 4 CANDU reactors by the end of 2089. In 2006, KAERI proposed a conceptual design of a geological disposal system (called KRS, Korean Reference disposal System for spent fuel for PWR and CANDU spent fuel, as a product of a 4-year research project from 2003 to 2006. The major result of the research was that it was feasible to construct a direct disposal system for 20,000 MtU of PWR spent fuels and 16,000 MtU of CANDU spent fuel in the Korean peninsula. Recently, KAERI and MEST launched a project to develop an advanced fuel cycle based on the pyroprocessing of PWR spent fuel to reduce the amount of HLW and reuse the valuable fissile material in PWR spent fuel. Thus, KAERI has developed a geological disposal system for high-level waste from the pyroprocessing of PWR spent fuel since 2007. However, since no decision was made for the CANDU spent fuel, KAERI improved the disposal density of KRS by introducing several improved concepts for the disposal canister. In this paper, the geological disposal systems developed so far are briefly outlined. The amount and characteristics of spent fuel and HLW, 4 kinds of disposal canisters, the characteristics of a buffer with domestic Ca-bentonite, and the results of a thermal design of deposition holes and disposal tunnels are described. The different disposal systems are compared in terms of their disposal density.

  10. Multi-Pack Disposal Concepts for Spent Fuel (Revision 1)

    International Nuclear Information System (INIS)

    Hardin, Ernest; Matteo, Edward N.; Hadgu, Teklu

    2016-01-01

    At the initiation of the Used Fuel Disposition (UFD) R&D campaign, international geologic disposal programs and past work in the U.S. were surveyed to identify viable disposal concepts for crystalline, clay/shale, and salt host media. Concepts for disposal of commercial spent nuclear fuel (SNF) and high-level waste (HLW) from reprocessing are relatively advanced in countries such as Finland, France, and Sweden. The UFD work quickly showed that these international concepts are all "enclosed,"whereby waste packages are emplaced in direct or close contact with natural or engineered materials . Alternative "open"modes (emplacement tunnels are kept open after emplacement for extended ventilation) have been limited to the Yucca Mountain License Application Design. Thermal analysis showed that if "enclosed"concepts are constrained by peak package/buffer temperature, that waste package capacity is limited to 4 PWR assemblies (or 9 BWR) in all media except salt. This information motivated separate studies: 1) extend the peak temperature tolerance of backfill materials, which is ongoing; and 2) develop small canisters (up to 4-PWR size) that can be grouped in larger multi-pack units for convenience of storage, transportation, and possibly disposal (should the disposal concept permit larger packages). A recent result from the second line of investigation is the Task Order 18 report: Generic Design for Small Standardized Transportation, Aging and Disposal Canister Systems. This report identifies disposal concepts for the small canisters (4-PWR size) drawing heavily on previous work, and for the multi-pack (16-PWR or 36-BWR).

  11. Multi-pack Disposal Concepts for Spent Fuel (Rev. 0)

    Energy Technology Data Exchange (ETDEWEB)

    Hadgu, Teklu [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hardin, Ernest [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Matteo, Edward N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-01

    At the initiation of the Used Fuel Disposition (UFD) R&D campaign, international geologic disposal programs and past work in the U.S. were surveyed to identify viable disposal concepts for crystalline, clay/shale, and salt host media (Hardin et al., 2012). Concepts for disposal of commercial spent nuclear fuel (SNF) and high-level waste (HLW) from reprocessing are relatively advanced in countries such as Finland, France, and Sweden. The UFD work quickly showed that these international concepts are all “enclosed,” whereby waste packages are emplaced in direct or close contact with natural or engineered materials . Alternative “open” modes (emplacement tunnels are kept open after emplacement for extended ventilation) have been limited to the Yucca Mountain License Application Design (CRWMS M&O, 1999). Thermal analysis showed that, if “enclosed” concepts are constrained by peak package/buffer temperature, waste package capacity is limited to 4 PWR assemblies (or 9-BWR) in all media except salt. This information motivated separate studies: 1) extend the peak temperature tolerance of backfill materials, which is ongoing; and 2) develop small canisters (up to 4-PWR size) that can be grouped in larger multi-pack units for convenience of storage, transportation, and possibly disposal (should the disposal concept permit larger packages). A recent result from the second line of investigation is the Task Order 18 report: Generic Design for Small Standardized Transportation, Aging and Disposal Canister Systems (EnergySolution, 2015). This report identifies disposal concepts for the small canisters (4-PWR size) drawing heavily on previous work, and for the multi-pack (16-PWR or 36-BWR).

  12. Multi-Pack Disposal Concepts for Spent Fuel (Revision 1)

    Energy Technology Data Exchange (ETDEWEB)

    Hardin, Ernest [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Matteo, Edward N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hadgu, Teklu [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-01-01

    At the initiation of the Used Fuel Disposition (UFD) R&D campaign, international geologic disposal programs and past work in the U.S. were surveyed to identify viable disposal concepts for crystalline, clay/shale, and salt host media. Concepts for disposal of commercial spent nuclear fuel (SNF) and high-level waste (HLW) from reprocessing are relatively advanced in countries such as Finland, France, and Sweden. The UFD work quickly showed that these international concepts are all “enclosed,” whereby waste packages are emplaced in direct or close contact with natural or engineered materials . Alternative “open” modes (emplacement tunnels are kept open after emplacement for extended ventilation) have been limited to the Yucca Mountain License Application Design. Thermal analysis showed that if “enclosed” concepts are constrained by peak package/buffer temperature, that waste package capacity is limited to 4 PWR assemblies (or 9 BWR) in all media except salt. This information motivated separate studies: 1) extend the peak temperature tolerance of backfill materials, which is ongoing; and 2) develop small canisters (up to 4-PWR size) that can be grouped in larger multi-pack units for convenience of storage, transportation, and possibly disposal (should the disposal concept permit larger packages). A recent result from the second line of investigation is the Task Order 18 report: Generic Design for Small Standardized Transportation, Aging and Disposal Canister Systems. This report identifies disposal concepts for the small canisters (4-PWR size) drawing heavily on previous work, and for the multi-pack (16-PWR or 36-BWR).

  13. Nuclear fuel production

    International Nuclear Information System (INIS)

    Randol, A.G.

    1985-01-01

    The production of new fuel for a power plant reactor and its disposition following discharge from the power plant is usually referred to as the ''nuclear fuel cycle.'' The processing of fuel is cyclic in nature since sometime during a power plant's operation old or ''depleted'' fuel must be removed and new fuel inserted. For light water reactors this step typically occurs once every 12-18 months. Since the time required for mining of the raw ore to recovery of reusable fuel materials from discharged materials can span up to 8 years, the management of fuel to assure continuous power plant operation requires simultaneous handling of various aspects of several fuel cycles, for example, material is being mined for fuel to be inserted in a power plant 2 years into the future at the same time fuel is being reprocessed from a discharge 5 years prior. Important aspects of each step in the fuel production process are discussed

  14. The disposal of Canada's nuclear fuel waste: a study of postclosure safety of in-room emplacement of used CANDU fuel in copper containers in permeable plutonic rock. Volume 5: radiological assessment

    International Nuclear Information System (INIS)

    Goodwin, B.W.; Andres, T.H.; Hajas, W.C.

    1996-06-01

    The concept for disposal of Canada's nuclear fuel waste involves isolating the waste in long-lived containers placed in a sealed vault at a depth of 500 to 1000 m in plutonic rock of the Canadian Shield. The concept permits a choice of methods, materials, sites and designs. The engineered system would be designed for the geological conditions of the disposal site. The technical feasibility of the disposal concept, and its impact on the environment and human health, have been presented in an Environmental Impact Statement (EIS) (AECL 1994a,b), supported by nine primary references (Davis et al. 1993; Davison et al. 1994a,b; Goodwin et al. 1994; Greber et al. 1994; Grondin et al. 1994; Johnson et al. 1994a,b; Simmons and Baumgartner 1994). In this report, we evaluate the long-term safety of a second hypothetical implementation of the concept that has several notable differences in site and design features compared to the EIS case study. We assume that the containers are constructed from copper, that they are placed within the disposal rooms, and that the vault is located in a more permeable rock domain. In this study, we consider the groundwater transport scenario and the radionuclides expected to be the most important contributors to dose and radiological risk. We use a prototype systems assessment code, comprising the SYVAC3 executive (the third generation of the SYstems Variability Analysis Code) and models representing the vault, geosphere and biosphere. We have not dealt with other, less likely scenarios, other radionuclides, chemically toxic elements, and some aspects of software quality assurance. The present study provides evidence that the second hypothetical implementation of the disposal concept would meet the radiological risk criterion established by the Atomic Energy Control Board by about an order of magnitude. The study illustrates the flexibility for designing engineered barriers to accommodate a permeable host-rock condition in which advection is the

  15. The disposal of Canada's nuclear fuel waste: a study of postclosure safety of in-room emplacement of used CANDU fuel in copper containers in permeable plutonic rock. Volume 4: biosphere model

    International Nuclear Information System (INIS)

    Zach, R.; Amiro, B.D.; Bird, G.A.; Macdonald, C.R.; Sheppard, M.I.; Sheppard, S.C.; Szekely, J.G.

    1996-06-01

    AECL (Atomic Energy of Canada Limited) has developed a disposal concept for Canada's nuclear fuel waste, which calls for a vault deep in plutonic rock of the Canadian Shield. The concept has been fully, documented in an environmental impact statement (EIS) for review by a panel under the Canadian Environmental Assessment Agency. The EIS includes the results of the EIS postclosure assessment case study to address the long term safety of the disposal concept. To more fully demonstrate the flexibility of the disposal concept and our assessment methodology, we are now carrying out another postclosure assessment study, which involves different assumptions and engineering options than those used in the EIS. In response to these changes, we have updated the BIOTRAC (BIOsphere Transport and Assessment Code) model developed for the EIS postclosure assessment case study. The main changes made to the BIOTRAC model are the inclusion of 36 Cl, 137 Cs, 239 Np and 243 Am; animals inhalation pathway; International Commission on Radiological Protection 60/61 human internal dose conversion factors; all the postclosure assessment nuclides in the dose calculations for non-human biota; and groundwater dose limits for 14 C, 16 C1 and 129 I for non-human biota to parallel these limits for humans. We have also reviewed and changed several parameter values, including evasion rates of gaseous nuclides from soil and release fractions of various nuclides from domestic water, and indicated changes that affect the geosphere/biosphere interface model. These changes make the BIOTRAC model more flexible. As a result of all of these changes, the BIOTRAC model has been significantly expanded and improved, although the changes do not greatly affect model predictions. The modified model for the present study is called BIOTRAC2 (BIOTRAC - Version 2). The full documentation of the BIOTRAC2 model includes the report by Davis et al. (1993a) and this report. (author). 105 refs., 13 tabs., 8 figs

  16. The disposal of Canada`s nuclear fuel waste: a study of postclosure safety of in-room emplacement of used CANDU fuel in copper containers in permeable plutonic rock. Volume 4: biosphere model

    Energy Technology Data Exchange (ETDEWEB)

    Zach, R; Amiro, B D; Bird, G A; Macdonald, C R; Sheppard, M I; Sheppard, S C; Szekely, J G

    1996-06-01

    AECL (Atomic Energy of Canada Limited) has developed a disposal concept for Canada`s nuclear fuel waste, which calls for a vault deep in plutonic rock of the Canadian Shield. The concept has been fully, documented in an environmental impact statement (EIS) for review by a panel under the Canadian Environmental Assessment Agency. The EIS includes the results of the EIS postclosure assessment case study to address the long term safety of the disposal concept. To more fully demonstrate the flexibility of the disposal concept and our assessment methodology, we are now carrying out another postclosure assessment study, which involves different assumptions and engineering options than those used in the EIS. In response to these changes, we have updated the BIOTRAC (BIOsphere Transport and Assessment Code) model developed for the EIS postclosure assessment case study. The main changes made to the BIOTRAC model are the inclusion of {sup 36}Cl, {sup 137}Cs, {sup 239}Np and {sup 243}Am; animals inhalation pathway; International Commission on Radiological Protection 60/61 human internal dose conversion factors; all the postclosure assessment nuclides in the dose calculations for non-human biota; and groundwater dose limits for {sup 14}C, {sup 16}C1 and {sup 129}I for non-human biota to parallel these limits for humans. We have also reviewed and changed several parameter values, including evasion rates of gaseous nuclides from soil and release fractions of various nuclides from domestic water, and indicated changes that affect the geosphere/biosphere interface model. These changes make the BIOTRAC model more flexible. As a result of all of these changes, the BIOTRAC model has been significantly expanded and improved, although the changes do not greatly affect model predictions. The modified model for the present study is called BIOTRAC2 (BIOTRAC - Version 2). The full documentation of the BIOTRAC2 model includes the report by Davis et al. (1993a) and this report. (author). 105

  17. The social impacts of the final disposal of spent nuclear fuel from the point of view of the inhabitants. Interview research; Kaeytetyn ydinpolttoaineen loppusijoituksen sosiaaliset vaikutukset kuntalaisten naekoekulmasta. Haastattelututkimus

    Energy Technology Data Exchange (ETDEWEB)

    Viinikainen, T. [Helsinki Univ. of Technology, Otaniemi (Finland). Centre for Urban and Regional Studies

    1998-12-01

    The research studied the social impacts of the final disposal of spent nuclear fuel by the means of qualitative methods. The principal research material consisted of 49 theme interviews carried out in four municipalities, Eurajoki, Kuhmo, Loviisa and Aeaenekoski, all of which have a candidate site for spent fuel disposal. The interviews covered residents living near the possible disposal site, local authorities from different sectors of the municipality, social workers, youth workers and teachers, local businesses, trade and other organisations as well as environmental and citizen movements. When considering the risk conceptions and worries over safety, a fairly consistent view on the safety of the different phases of the project can be identified in all the municipalities. The transportation of nuclear waste aroused definitely the most worries over safety, especially because of the danger of sabotage and traffic accidents. When considering the encapsulation stage` the interviews revealed that risks are associated with this stage because it entails a `human factor`: the treatment of a dangerous substance in a disposal site above ground is considered hazardous. When considering the time after the closing of the disposal system, an opinion could be formed on the basis of the interviews that a final disposal system in hard bedrock would probably perform adequately in the short term but there can be no certain knowledge of risks in the long term. Confidence or lack of confidence in the safety of the project appeared as the most important factor causing social impacts. As a summary of the results, it can be concluded that especially (1) familiarity of the risk and (2) the possibility that taking risks are advantageous to oneself increase the acceptability of the risk. These are also the factors which distinguish the municipalities with nuclear power plants (Loviisa and Eurajoki) from the other two municipalities. The fair allocation of risks as well as the division of

  18. Nuclear fuel element

    International Nuclear Information System (INIS)

    Mogard, J.H.

    1977-01-01

    A nuclear fuel element is disclosed for use in power producing nuclear reactors, comprising a plurality of axially aligned ceramic cylindrical fuel bodies of the sintered type, and a cladding tube of metal or metal alloys, wherein said cladding tube on its cylindrical inner surface is provided with a plurality of slightly protruding spacing elements distributed over said inner surface

  19. A global sensitivity analysis of two-phase flow between fractured crystalline rock and bentonite with application to spent nuclear fuel disposal.

    Science.gov (United States)

    Dessirier, Benoît; Frampton, Andrew; Jarsjö, Jerker

    2015-11-01

    Geological disposal of spent nuclear fuel in deep crystalline rock is investigated as a possible long term solution in Sweden and Finland. The fuel rods would be cased in copper canisters and deposited in vertical holes in the floor of deep underground tunnels, embedded within an engineered bentonite buffer. Recent experiments at the Äspö Hard Rock Laboratory (Sweden) showed that the high suction of unsaturated bentonite causes a de-saturation of the adjacent rock at the time of installation, which was also independently predicted in model experiments. Remaining air can affect the flow patterns and alter bio-geochemical conditions, influencing for instance the transport of radionuclides in the case of canister failure. However, thus far, observations and model realizations are limited in number and do not capture the conceivable range and combination of parameter values and boundary conditions that are relevant for the thousands of deposition holes envisioned in an operational final repository. In order to decrease this knowledge gap, we introduce here a formalized, systematic and fully integrated approach to study the combined impact of multiple factors on air saturation and dissolution predictions, investigating the impact of variability in parameter values, geometry and boundary conditions on bentonite buffer saturation times and on occurrences of rock de-saturation. Results showed that four parameters consistently appear in the top six influential factors for all considered output (target) variables: the position of the fracture intersecting the deposition hole, the background rock permeability, the suction representing the relative humidity in the open tunnel and the far field pressure value. The combined influence of these compared to the other parameters increases as one targets a larger fraction of the buffer reaching near-saturation. Strong interaction effects were found, which means that some parameter combinations yielded results (e.g., time to

  20. Nuclear fuel cycle

    International Nuclear Information System (INIS)

    1993-01-01

    Status of different nuclear fuel cycle phases in 1992 is discussed including the following issues: uranium exploration, resources, supply and demand, production, market prices, conversion, enrichment; reactor fuel technology; spent fuel management, as well as trends of these phases development up to the year 2010. 10 refs, 11 figs, 15 tabs

  1. Nuclear reactor fuel assembly

    International Nuclear Information System (INIS)

    Sasaki, Y.; Tashima, J.

    1975-01-01

    A description is given of nuclear reactor fuel assemblies arranged in the form of a lattice wherein there is attached to the interface of one of two adjacent fuel assemblies a plate spring having a concave portion curved toward said interface and to the interface of the other fuel assembly a plate spring having a convex portion curved away from said interface

  2. Social awareness on nuclear fuel cycle

    International Nuclear Information System (INIS)

    Tanigaki, Toshihiko

    2006-01-01

    In the present we surveyed public opinion regarding the nuclear fuel cycle to find out about the social awareness about nuclear fuel cycle and nuclear facilities. The study revealed that people's image of nuclear power is more familiar than the image of the nuclear fuel cycle. People tend to display more recognition and concern towards nuclear power and reprocessing plants than towards other facilities. Comparatively speaking, they tend to perceive radioactive waste disposal facilities and nuclear power plants as being highly more dangerous than reprocessing plants. It is found also that with the exception of nuclear power plants don't know very much whether nuclear fuel cycle facilities are in operation in Japan or not. The results suggests that 1) the relatively mild image of the nuclear fuel cycle is the result of the interactive effect of the highly dangerous image of nuclear power plants and the less dangerous image of reprocessing plants; and 2) that the image of a given plant (nuclear power plant, reprocessing plant, radioactive waste disposal facility) is influenced by the fact of whether the name of the plant suggests the presence of danger or not. (author)

  3. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    Anthony, A.J.

    1980-01-01

    A bimetallic spacer means is cooperatively associated with a nuclear fuel assembly and operative to resist the occurrence of in-reactor bowing of the nuclear fuel assembly. The bimetallic spacer means in one embodiment of the invention includes a space grid formed, at least principally, of zircaloy to the external surface of which are attached a plurality of stainless steel strips. In another embodiment the strips are attached to fuel pins. In each of the embodiments, the stainless steel strips during power production expand outwardly to a greater extent than do the members to which the stainless steel strips are attached, thereby forming stiff springs which abut against like bimetallic spacer means with which the other nuclear fuel assemblies are provided in a given nuclear reactor core to thus prevent the occurrence of in-reactor bowing of the nuclear fuel assemblies. (author)

  4. Axially alignable nuclear fuel pellets

    International Nuclear Information System (INIS)

    Johansson, E.B.; Klahn, D.H.; Marlowe, M.O.

    1978-01-01

    An axially alignable nuclear fuel pellet of the type stacked in end-to-end relationship within a tubular cladding is described. Fuel cladding failures can occur at pellet interface locations due to mechanical interaction between misaligned fuel pellets and the cladding. Mechanical interaction between the cladding and the fuel pellets loads the cladding and causes increased cladding stresses. Nuclear fuel pellets are provided with an end structure that increases plastic deformation of the pellets at the interface between pellets so that lower alignment forces are required to straighten axially misaligned pellets. Plastic deformation of the pellet ends results in less interactions beween the cladding and the fuel pellets and significantly lowers cladding stresses. The geometry of pellets constructed according to the invention also reduces alignment forces required to straighten fuel pellets that are tilted within the cladding. Plastic deformation of the pellets at the pellet interfaces is increased by providing pellets with at least one end face having a centrally-disposed raised area of convex shape so that the mean temperature and shear stress of the contact area is higher than that of prior art pellets

  5. Nuclear fuel storage facility

    International Nuclear Information System (INIS)

    Matsumoto, Takashi; Isaka, Shinji.

    1987-01-01

    Purpose: To increase the spent fuel storage capacity and reduce the installation cost in a nuclear fuel storage facility. Constitution: Fuels handled in the nuclear fuel storage device of the present invention include the following four types: (1) fresh fuels, (2) 100 % reactor core charged fuels, (3) spent fuels just after taking out and (4) fuels after a certain period (for example one half-year) from taking out of the reactor. Reactivity is high for the fuels (1), and some of fuels (2), while low in the fuels (3) (4), Source intensity is strong for the fuels (3) and some of the fuels (2), while it is low for the fuels (1) and (4). Taking notice of the fact that the reactivity, radioactive source intensity and generated after heat are different in the respective fuels, the size of the pool and the storage capacity are increased by the divided storage control. While on the other hand, since the division is made in one identical pool, the control method becomes important, and the working range is restricted by means of a template, interlock, etc., the operation mode of the handling machine is divided into four, etc. for preventing errors. (Kamimura, M.)

  6. Dynamic Systems Analysis Report for Nuclear Fuel Recycle

    Energy Technology Data Exchange (ETDEWEB)

    Brent Dixon; Sonny Kim; David Shropshire; Steven Piet; Gretchen Matthern; Bill Halsey

    2008-12-01

    This report examines the time-dependent dynamics of transitioning from the current United States (U.S.) nuclear fuel cycle where used nuclear fuel is disposed in a repository to a closed fuel cycle where the used fuel is recycled and only fission products and waste are disposed. The report is intended to help inform policy developers, decision makers, and program managers of system-level options and constraints as they guide the formulation and implementation of advanced fuel cycle development and demonstration efforts and move toward deployment of nuclear fuel recycling infrastructure.

  7. Nuclear spent fuel management. Experience and options

    International Nuclear Information System (INIS)

    1986-01-01

    Spent nuclear fuel can be stored safely for long periods at relatively low cost, but some form of permanent disposal will eventually be necessary. This report examines the options for spent fuel management, explores the future prospects for each stage of the back-end of the fuel cycle and provides a thorough review of past experience and the technical status of the alternatives. Current policies and practices in twelve OECD countries are surveyed

  8. High-level nuclear waste disposal

    International Nuclear Information System (INIS)

    Burkholder, H.C.

    1985-01-01

    The meeting was timely because many countries had begun their site selection processes and their engineering designs were becoming well-defined. The technology of nuclear waste disposal was maturing, and the institutional issues arising from the implementation of that technology were being confronted. Accordingly, the program was structured to consider both the technical and institutional aspects of the subject. The meeting started with a review of the status of the disposal programs in eight countries and three international nuclear waste management organizations. These invited presentations allowed listeners to understand the similarities and differences among the various national approaches to solving this very international problem. Then seven invited presentations describing nuclear waste disposal from different perspectives were made. These included: legal and judicial, electric utility, state governor, ethical, and technical perspectives. These invited presentations uncovered several issues that may need to be resolved before high-level nuclear wastes can be emplaced in a geologic repository in the United States. Finally, there were sixty-six contributed technical presentations organized in ten sessions around six general topics: site characterization and selection, repository design and in-situ testing, package design and testing, disposal system performance, disposal and storage system cost, and disposal in the overall waste management system context. These contributed presentations provided listeners with the results of recent applied RandD in each of the subject areas

  9. Nuclear fuel activities in Belgium

    Energy Technology Data Exchange (ETDEWEB)

    Bairiot, H

    1997-12-01

    In his presentation on nuclear fuel activities in belgium the author considers the following directions of this work: fuel fabrication, NPP operation, fuel performance, research and development programmes.

  10. Boosting nuclear fuels

    International Nuclear Information System (INIS)

    Demarthon, F.; Donnars, O.; Dupuy-Maury, F.

    2002-01-01

    This dossier gives a broad overview of the present day status of the nuclear fuel cycle in France: 1 - the revival of nuclear power as a solution to the global warming and to the increase of worldwide energy needs; 2 - the security of uranium supplies thanks to the reuse of weapon grade highly enriched uranium; 3 - the fabrication of nuclear fuels from the mining extraction to the enrichment processes, the fabrication of fuel pellets and the assembly of fuel rods; 4 - the new composition of present day fuels (UO x and chromium-doped pellets); 5 - the consumption of plutonium stocks and the Corail and Apa fuel assemblies for the reduction of plutonium stocks and the preservation of uranium resources. (J.S.)

  11. Fuel cycle and waste management: A perspective from British nuclear fuels plc

    International Nuclear Information System (INIS)

    Holmes, R.G.G.; Fairhall, G.A.; Robbins, R.A.

    1996-01-01

    The phrase fuel cycle and waste management implies two separate and distinct activities. British Nuclear Fuels plc (BNFL) has adopted a holistic approach to the fuel cycle that integrates the traditional fuel cycle activities of conversion to uranium hexafluoride, fuel fabrication, power generation, and reprocessing with waste arisings, its subsequent treatment, and disposal

  12. User`s manual for the CC3 computer models of the concept for disposal of Canada`s nuclear fuel waste

    Energy Technology Data Exchange (ETDEWEB)

    Dougan, K D; Wojciechowski, L C

    1995-06-01

    Atomic Energy of Canada Limited (AECL) is assessing a concept for disposing of CANDU reactor fuel waste in a vault deep in plutonic rock of the Canadian Shield. A computer program called the Systems Variability Analysis Code (SYVAC) has been developed as an analytical tool for the postclosure (long-term) assessment of the concept, and for environmental assessments of other systems. SYVAC3, the third generation of the code, is an executive program that directs repeated simulation of the disposal system, which is represented by the CC3 (Canadian Concept, generation 3) models comprising a design-specific vault, a site-specific geosphere and a biosphere typical of the Canadian Shield. (author). 23 refs., 7 tabs., 21 figs.

  13. A concept to combine DOE waste minimization goals with commercial utility needs for a universal container system for spent nuclear fuel storage, transportation, and disposal

    International Nuclear Information System (INIS)

    Falci, F.P.; Smith, M.L.; Sorenson, K.B.

    1993-01-01

    The concept of storing, transporting, and disposing of spent fuel using a single package has obvious advantages. Coupling this concept with using contaminated scrap metal from the EM Complex will help reduce a significant portion of waste that would otherwise need to be packaged, stored, and disposed of as low level radioactive waste. Assuming a material of cost of $1 per pound for 800,000 tons of metal needed for universal containers, the potential material cost savings from manufacturing these containers from what would otherwise be a waste product is about $1.5 billion. Clearly, this concept is novel and has significant obstacles that need to be addressed and overcome; particularly in the regulatory arena. However, the potential benefits warrant the evaluation of the proposal on several fronts. DOE OCRWM should seriously consider the universal cask concept for management of spent fuel. DOE EM should pursue the development of melting contaminated scrap for the manufacture of casks. Finally, EM and OCRWM should cooperate on the evaluation of using EM contaminated scrap metal for the manufacture of universal casks for OCRWM spent fuel

  14. Nuclear fuel pellet transfer escalator

    International Nuclear Information System (INIS)

    Huggins, T.B. Sr.; Roberts, E.; Edmunds, M.O.

    1991-01-01

    This patent describes a nuclear fuel pellet escalator for loading nuclear fuel pellets into a sintering boat. It comprises a generally horizontally-disposed pellet transfer conveyor for moving pellets in single file fashion from a receiving end to a discharge end thereof, the conveyor being mounted about an axis at its receiving end for pivotal movement to generally vertically move its discharge end toward and away from a sintering boat when placed below the discharge end of the conveyor, the conveyor including an elongated arm swingable vertically about the axis and having an elongated channel recessed below an upper side of the arm and extending between the receiving and discharge ends of the conveyor; a pellet dispensing chute mounted to the arm of the conveyor at the discharge end thereof and extending therebelow such that the chute is carried at the discharge end of the conveyor for generally vertical movement therewith toward and away from the sintering boat

  15. Electrochemical reprocessing of nuclear fuels

    International Nuclear Information System (INIS)

    Brambilla, G.; Sartorelli, A.

    1980-01-01

    A method is described for the reprocessing of irradiated nuclear fuel which is particularly suitable for use with fuel from fast reactors and has the advantage of being a dry process in which there is no danger of radiation damage to a solvent medium as in a wet process. It comprises the steps of dissolving the fuel in a salt melt under such conditions that uranium and plutonium therein are converted to sulphate form. The plutonium sulphate may then be thermally decomposed to PuO 2 and removed. The salt melt is then subjected to electrolysis conditions to achieve cathodic deposition of UO 2 (and possibly PuO 2 ). The salt melt can then be recycled or conditioned for final disposal. (author)

  16. Fuel assemblies for nuclear reactors

    International Nuclear Information System (INIS)

    Jabsen, F.S.

    1979-01-01

    In a nuclear fuel assembly, hollow guide posts protrude into a fuel assembly and fitting grill from a biased spring pad with a plunger that moves with the spring pad plugging one end of each of the guide posts. A plate on the end fitting grill that has a hole for fluid discharge partially plugs the other end of the guide post. Pressurized water coolant that fills the guide post volume acts as a shock absorber and should the reactor core receive a major seismic or other shock, the fuel assembly is compelled to move towards a pad depending from a transversely disposed support grid. The pad bears against the spring pad and the plunger progressively blocks the orifices provided by slots in the guide posts thus gradually absorbing the applied shock. After the orifice has been completely blocked, controlled fluid discharge continues through a hole coil spring cooperating in the attenuation of the shock. (author)

  17. Nuclear dynamics consequence analysis of SNF disposed in volcanic tuff

    International Nuclear Information System (INIS)

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

    1998-05-01

    This paper describes criticality analyses for spent nuclear fuels in a geologic repository. The analyses investigated criticality potential, criticality excursion consequences, and the probability frequency for nuclear criticality. Key findings include: expected number of fissions per excursion range from 10 17 to 10 20 , repeated rate of criticalities range from 3 to 30 per year, and the probability frequency for criticality initiators (based on rough-order-of-magnitude calculations) is 7x10 -7 . Overall results indicate that criticality consequences are a minor contribution to the biological hazards caused by the disposal of spent nuclear material

  18. Testing to evaluate the suitability of waste forms developed for electrometallurgically treated spent sodium-bonded nuclear fuel for disposal in the Yucca Mountain reporsitory.

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, W. E.

    2006-01-31

    The results of laboratory testing and modeling activities conducted to support the development of waste forms to immobilize wastes generated during the electrometallurgical treatment of spent sodium-bonded nuclear fuel and their qualification for disposal in the federal high-level radioactive waste repository are summarized in this report. Tests and analyses were conducted to address issues related to the chemical, physical, and radiological properties of the waste forms relevant to qualification. These include the effects of composition and thermal treatments on the phase stability, radiation effects, and methods for monitoring product consistency. Other tests were conducted to characterize the degradation and radionuclide release behaviors of the ceramic waste form (CWF) used to immobilize waste salt and the metallic waste form (MWF) used to immobilize metallic wastes and to develop models for calculating the release of radionuclides over long times under repository-relevant conditions. Most radionuclides are contained in the binder glass phase of the CWF and in the intermetallic phase of the MWF. The release of radionuclides from the CWF is controlled by the dissolution rate of the binder glass, which can be tracked using the same degradation model that is used for high-level radioactive waste (HLW) glass. Model parameters measured for the aqueous dissolution of the binder glass are used to model the release of radionuclides from a CWF under all water-contact conditions. The release of radionuclides from the MWF is element-specific, but the release of U occurs the fastest under most test conditions. The fastest released constituent was used to represent all radionuclides in model development. An empirical aqueous degradation model was developed to describe the dependence of the radionuclide release rate from a MWF on time, pH, temperature, and the Cl{sup -} concentration. The models for radionuclide release from the CWF and MWF are both bounded by the HLW glass

  19. Nuclear Fuel Reprocessing

    International Nuclear Information System (INIS)

    Simpson, Michael F.; Law, Jack D.

    2010-01-01

    This is a submission for the Encyclopedia of Sustainable Technology on the subject of Reprocessing Spent Nuclear Fuel. Nuclear reprocessing is the chemical treatment of spent fuel involving separation of its various constituents. Principally, it is used to recover useful actinides from the spent fuel. Radioactive waste that cannot be re-used is separated into streams for consolidation into waste forms. The first known application of nuclear reprocessing was within the Manhattan Project to recover material for nuclear weapons. Currently, reprocessing has a peaceful application in the nuclear fuel cycle. A variety of chemical methods have been proposed and demonstrated for reprocessing of nuclear fuel. The two most widely investigated and implemented methods are generally referred to as aqueous reprocessing and pyroprocessing. Each of these technologies is described in detail in Section 3 with numerous references to published articles. Reprocessing of nuclear fuel as part of a fuel cycle can be used both to recover fissionable actinides and to stabilize radioactive fission products into durable waste forms. It can also be used as part of a breeder reactor fuel cycle that could result in a 14-fold or higher increase in energy utilization per unit of natural uranium. Reprocessing can also impact the need for geologic repositories for spent fuel. The volume of waste that needs to be sent to such a repository can be reduced by first subjecting the spent fuel to reprocessing. The extent to which volume reduction can occur is currently under study by the United States Department of Energy via research at various national laboratories and universities. Reprocessing can also separate fissile and non-fissile radioactive elements for transmutation.

  20. Final disposal of spent fuels and high activity waste: status and trends in the world

    International Nuclear Information System (INIS)

    Herscovich de Pahissa, Marta

    2007-01-01

    Geological disposal of spent nuclear fuel and high level waste from reprocessing, properly conditioned, is described. This issue is a major challenge related to radioactive waste management. Several options are analyzed, such as application of separation and transmutation to high level waste before final disposal; need of multinational repositories; a phased approach to deep geological disposal and long term surface storage. Bearing in mind this information, a future article will report the state of art in the world. (author) [es

  1. Spent nuclear fuel storage

    International Nuclear Information System (INIS)

    Romanato, Luiz Sergio

    2005-01-01

    When a country becomes self-sufficient in part of the nuclear cycle, as production of fuel that will be used in nuclear power plants for energy generation, it is necessary to pay attention for the best method of storing the spent fuel. Temporary storage of spent nuclear fuel is a necessary practice and is applied nowadays all over the world, so much in countries that have not been defined their plan for a definitive repository, as well for those that already put in practice such storage form. There are two main aspects that involve the spent fuels: one regarding the spent nuclear fuel storage intended to reprocessing and the other in which the spent fuel will be sent for final deposition when the definitive place is defined, correctly located, appropriately characterized as to several technical aspects, and licentiate. This last aspect can involve decades of studies because of the technical and normative definitions at a given country. In Brazil, the interest is linked with the storage of spent fuels that will not be reprocessed. This work analyses possible types of storage, the international panorama and a proposal for future construction of a spent nuclear fuel temporary storage place in the country. (author)

  2. Nuclear fuel element

    International Nuclear Information System (INIS)

    Yamamoto, Seigoro.

    1994-01-01

    Ultrafine particles of a thermal neutron absorber showing ultraplasticity is dispersed in oxide ceramic fuels by more than 1% to 10% or lower. The ultrafine particles of the thermal neutron absorber showing ultrafine plasticity is selected from any one of ZrGd, HfEu, HfY, HfGd, ZrEu, and ZrY. The thermal neutron absorber is converted into ultrafine particles and solid-solubilized in a nuclear fuel pellet, so that the dispersion thereof into nuclear fuels is made uniform and an absorbing performance of the thermal neutrons is also made uniform. Moreover, the characteristics thereof, for example, physical properties such as expansion coefficient and thermal conductivity of the nuclear fuels are also improved. The neutron absorber, such as ZrGd or the like, can provide plasticity of nuclear fuels, if it is mixed into the nuclear fuels for showing the plasticity. The nuclear fuel pellets are deformed like an hour glass as burning, but, since the end portion thereof is deformed plastically within a range of a repulsive force of the cladding tube, there is no worry of damaging a portion of the cladding tube. (N.H.)

  3. Potential information requirements for spent nuclear fuel

    International Nuclear Information System (INIS)

    Disbrow, J.A.

    1991-01-01

    This paper reports that the Energy Information Administration (EIA) has performed analyses of the requirements for data and information for the management of commercial spent nuclear fuel (SNF) designated for disposal under the Nuclear Waste Policy Act (NWPA). Subsequently, the EIA collected data on the amounts and characteristics of SNF stored at commercial nuclear facilities. Most recently, the EIA performed an analysis of the international and domestic laws and regulations which have been established to ensure the safeguarding, accountability, and safe management of special nuclear materials (SNM). The SNM of interest are those designated for permanent disposal by the NWPA. This analysis was performed to determine what data and information may be needed to fulfill the specific accountability responsibilities of the Department of Energy (DOE) related to SNF handling, transportation, storage and disposal; to work toward achieving a consistency between nuclear fuel assembly identifiers and material weights as reported by the various responsible parties; and to assist in the revision of the Nuclear Fuel Data Form RW-859 used to obtain spent nuclear fuel characteristics data from the nuclear utilities

  4. No nuclear power. No disposal facility?

    Energy Technology Data Exchange (ETDEWEB)

    Feinhals, J. [DMT GmbH und Co.KG, Hamburg (Germany)

    2016-07-01

    Countries with a nuclear power programme are making strong efforts to guarantee the safe disposal of radioactive waste. The solutions in those countries are large disposal facilities near surface or in deep geological layers depending on the activity and half-life of the nuclides in the waste. But what will happen with the radioactive waste in countries that do not have NPPs but have only low amounts of radioactive waste from medical, industrial and research facilities as well as from research reactors? Countries producing only low amounts of radioactive waste need convincing solutions for the safe and affordable disposal of their radioactive waste. As they do not have a fund by an operator of nuclear power plants, those countries need an appropriate and commensurate solution for the disposal of their waste. In a first overview five solutions seem to be appropriate: (i) the development of multinational disposal facilities by using the existing international knowhow; (ii) common disposal with hazardous waste; (iii) permanent storage; (iv) use of an existing mine or tunnel; (v) extension of the borehole disposal concept for all the categories of radioactive wastes.

  5. Back-end of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Choi, J.S.

    2002-01-01

    Current strategies of the back-end nuclear fuel cycles are: (1) direct-disposal of spent fuel (Open Cycle), and (2) reprocessing of the spent fuel and recycling of the recovered nuclear materials (Closed Cycle). The selection of these strategies is country-specific, and factors affecting selection of strategy are identified and discussed in this paper. (author)

  6. Reprocessing of spent nuclear fuel

    International Nuclear Information System (INIS)

    Schmitt, D.

    1985-01-01

    How should the decision in favour of reprocessing and against alternative waste management concepts be judged from an economic standpoint. Reprocessing is not imperative neither for resource-economic reasons nor for nuclear energy strategy reasons. On the contrary, the development of an ultimate storage concept representing a real alternative promising to close, within a short period of time, the nuclear fuel cycle at low cost. At least, this is the result of an extensive economic efficiency study recently submitted by the Energy Economics Institute which investigated all waste management concepts relevant for the Federal Republic of Germany in the long run, i.e. direct ultimate storage of spent fuel elements (''Other waste disposal technologies'' - AE) as well as reprocessing of spent fuel elements where re-usable plutonium and uranium are recovered and radioactive waste goes to ultimate storage (''Integrated disposal'' - IE). Despite such fairly evident results, the government of the Federal Republic of Germany has favoured the construction of a reprocessing plant. From an economic point of view there is no final answer to the question whether or not the argumentation is sufficient to justify the decision to construct a reprocessing plant. This is true for both the question of technical feasibility and issues of overriding significance of a political nature. (orig./HSCH) [de

  7. Nuclear fuel powder transfer device

    International Nuclear Information System (INIS)

    Komono, Akira

    1998-01-01

    A pair of parallel rails are laid between a receiving portion to a molding portion of a nuclear fuel powder transfer device. The rails are disposed to the upper portion of a plurality of parallel support columns at the same height. A powder container is disposed while being tilted in the inside of the vessel main body of a transfer device, and rotational shafts equipped with wheels are secured to right and left external walls. A nuclear powder to be mixed, together with additives, is supplied to the powder container of the transfer device. The transfer device engaged with the rails on the receiving side is transferred toward the molding portion. The wheels are rotated along the rails, and the rotational shafts, the vessel main body and the powder container are rotated. The nuclear powder in the tilted powder container disposed is rotated right and left and up and down by the rotation, and the powder is mixed satisfactory when it reaches the molding portion. (I.N.)

  8. Nuclear fuel element

    International Nuclear Information System (INIS)

    Yamanaka, Tsuneyasu.

    1976-01-01

    Purpose: To provide a mechanism for the prevention of fuel pellet dislocation in fuel can throughout fuel fablication, fuel transportation and reactor operation. Constitution: A plenum spacer as a mechanism for the prevention of fuel pellet dislocation inserted into a cladding tube comprises split bodies bundled by a frame and an expansion body being capable of inserting into the central cavity of the split bodies. The expansion body is, for example, in a conical shape and the split bodies are formed so that they define in the center portion, when disposed along the inner wall of the cladding tube, a gap capable of inserting the conical body. The plenum spacer is assembled by initially inserting the split bodies in a closed state into the cladding tube after the loading of the pellets, pressing their peripheral portions and then inserting the expansion body into the space to urge the split bodies to the inner surface of the cladding tube. (Kawakami, Y.)

  9. Transportation of nuclear fuel

    International Nuclear Information System (INIS)

    Prowse, D.R.

    1979-01-01

    Shipment of used fuel from nuclear reactors to a central fuel management facility is discussed with particular emphasis on the assessment of the risk to the public due to these shipments. The methods of transporting used fuel in large shipping containers is reviewed. In terms of an accident scenario, it is demonstrated that the primary risk of transport of used fuel is due to injury and death in common road accidents. The radiological nature of the used fuel cargo is, for all practical purposes, an insignificant factor in the total risk to the public. (author)

  10. Nuclear waste disposal: Gambling on Yucca Mountain

    International Nuclear Information System (INIS)

    Ginsburg, S.

    1995-01-01

    This document describes the historical aspects of nuclear energy ,nuclear weapons usage, and development of the nuclear bureaucracy in the United States, and discusses the selection and siting of Yucca Mountain, Nevada for a federal nuclear waste repository. Litigation regarding the site selection and resulting battles in the political arena and in the Nevada State Legislature are also presented. Alternative radioactive waste disposal options, risk assessments of the Yucca Mountain site, and logistics regarding the transportation and storage of nuclear waste are also presented. This document also contains an extensive bibliography

  11. Fuel assemblies for nuclear reactor

    International Nuclear Information System (INIS)

    Nishi, Akihito.

    1987-01-01

    Purpose: To control power-up rate at the initial burning stage of new fuel assemblies due to fuel exchange in a pressure tube type power reactor. Constitution: Burnable poisons are disposed to a most portion of fuel pellets in a fuel assembly to such a low concentration as the burn-up rate changes with time at the initial stage of the burning. The most portion means substantially more than one-half part of the pellets and gadolinia is used as burn-up poisons to be dispersed and the concentration is set to less than about 0.2 %. Upon elapse of about 15 days after the charging, the burnable poisons are eliminated and the infinite multiplication factors are about at 1.2 to attain a predetermined power state. Since the power-up rate of the nuclear reactor fuel assembly is about 0.1 % power/hour and the power-up rate of the fuel assembly around the exchanged channel is lower than that, it can be lowered sufficiently than the limit for the power-up rate practiced upon reactor start-up thereby enabling to replace fuels during power operation. (Horiuchi, T.)

  12. Nuclear fuel banks

    International Nuclear Information System (INIS)

    Anon.

    2010-01-01

    In december 2010 IAEA gave its agreement for the creation of a nuclear fuel bank. This bank will allow IAEA to help member countries that renounce to their own uranium enrichment capacities. This bank located on one or several member countries will belong to IAEA and will be managed by IAEA and its reserve of low enriched uranium will be sufficient to fabricate the fuel for the first load of a 1000 MW PWR. Fund raising has been successful and the running of the bank will have no financial impact on the regular budget of the IAEA. Russia has announced the creation of the first nuclear fuel bank. This bank will be located on the Angarsk site (Siberia) and will be managed by IAEA and will own 120 tonnes of low-enriched uranium fuel (between 2 and 4.95%), this kind of fuel is used in most Russian nuclear power plants. (A.C.)

  13. Nuclear fuel grid outer strap

    International Nuclear Information System (INIS)

    Duncan, R.; Craver, J.E.

    1989-01-01

    This patent describes a nuclear reactor fuel assembly grid. It comprises a first outer grip strap segment end. The first end having a first tab arranged in substantially the same plane as the plane defined by the first end; a second outer grip strap end. The second end having a second slot arranged in substantially the same plane as the plane defined by the second end, with the tab being substantially disposed in the slot, defining a socket therebetween; and a fort tine interposed substantially perpendicularly in the socket

  14. Radioecology of nuclear fuel cycles

    International Nuclear Information System (INIS)

    Schreckhise, R.G.; Cadwell, L.L.; Emery, R.M.

    1981-01-01

    This study provides information to help assess the environmental impacts and certain potential human hazards associated with nuclear fuel cycles. A data base is being developed to define and quantify biological transport routes which will permit credible predictions and assessment of routine and potential large-scale releases of radionuclides and other toxic materials. Information obtained from existing storage and disposal sites will provide a meaningful radioecological perspective with which to improve the effectiveness of waste management practices. This paper focuses on terrestrial and aquatic radioecology of waste management areas and biotic transport parameters

  15. Waste disposal[1997 Scientific Report of the Belgian Nuclear Research Centre

    Energy Technology Data Exchange (ETDEWEB)

    Neerdael, B.; Marivoet, J.; Put, M.; Verstricht, J.; Van Iseghem, P.; Buyens, M.

    1998-07-01

    The primary mission of the Waste Disposal programme at the Belgian Nuclear Research Centre SCK/CEN is to propose, develop, and assess solutions for the safe disposal of radioactive waste. In Belgium, deep geological burial in clay is the primary option for the disposal of High-Level Waste and spent nuclear fuel. The main achievements during 1997 in the following domains are described: performance assessment, characterization of the geosphere, characterization of the waste, migration processes, underground infrastructure.

  16. The nuclear fuel cycle

    International Nuclear Information System (INIS)

    Jones, P.M.S.

    1987-01-01

    This chapter explains the distinction between fissile and fertile materials, examines briefly the processes involved in fuel manufacture and management, describes the alternative nuclear fuel cycles and considers their advantages and disadvantages. Fuel management is usually divided into three stages; the front end stage of production and fabrication, the back end stage which deals with the fuel after it is removed from the reactor (including reprocessing and waste treatment) and the stage in between when the fuel is actually in the reactor. These stages are illustrated and explained in detail. The plutonium fuel cycle and thorium-uranium-233 fuel cycle are explained. The differences between fuels for thermal reactors and fast reactors are explained. (U.K.)

  17. The nuclear fuel cycle

    International Nuclear Information System (INIS)

    Patarin, L.

    2002-01-01

    This book treats of the different aspects of the industrial operations linked with the nuclear fuel, before and after its use in nuclear reactors. The basis science of this nuclear fuel cycle is chemistry. Thus a recall of the elementary notions of chemistry is given in order to understand the phenomena involved in the ore processing, in the isotope enrichment, in the fabrication of fuel pellets and rods (front-end of the cycle), in the extraction of recyclable materials (residual uranium and plutonium), and in the processing and conditioning of wastes (back-end of the fuel cycle). Nuclear reactors produce about 80% of the French electric power and the Cogema group makes 40% of its turnover at the export. Thus this book contains also some economic and geopolitical data in order to clearly position the stakes. The last part, devoted to the management of wastes, presents the solutions already operational and also the research studies in progress. (J.S.)

  18. Nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    White, D.

    1981-01-01

    A simple friction device for cutting nuclear fuel wrappers comprising a thin metal disc clamped between two large diameter clamping plates. A stream of gas ejected from a nozzle is used as coolant. The device may be maintained remotely. (author)

  19. Spent Nuclear Fuel Alternative Technology Decision Analysis

    International Nuclear Information System (INIS)

    Shedrow, C.B.

    1999-01-01

    The Westinghouse Savannah River Company (WSRC) made a FY98 commitment to the Department of Energy (DOE) to recommend a technology for the disposal of aluminum-based spent nuclear fuel (SNF) at the Savannah River Site (SRS). The two technologies being considered, direct co-disposal and melt and dilute, had been previously selected from a group of eleven potential SNF management technologies by the Research Reactor Spent Nuclear Fuel Task Team chartered by the DOE''s Office of Spent Fuel Management. To meet this commitment, WSRC organized the SNF Alternative Technology Program to further develop the direct co-disposal and melt and dilute technologies and ultimately provide a WSRC recommendation to DOE on a preferred SNF alternative management technology

  20. Spent Nuclear Fuel Alternative Technology Decision Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shedrow, C.B.

    1999-11-29

    The Westinghouse Savannah River Company (WSRC) made a FY98 commitment to the Department of Energy (DOE) to recommend a technology for the disposal of aluminum-based spent nuclear fuel (SNF) at the Savannah River Site (SRS). The two technologies being considered, direct co-disposal and melt and dilute, had been previously selected from a group of eleven potential SNF management technologies by the Research Reactor Spent Nuclear Fuel Task Team chartered by the DOE''s Office of Spent Fuel Management. To meet this commitment, WSRC organized the SNF Alternative Technology Program to further develop the direct co-disposal and melt and dilute technologies and ultimately provide a WSRC recommendation to DOE on a preferred SNF alternative management technology.

  1. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    Hayashi, Hiroshi; Watari, Yoshio; Hizahara, Hiroshi; Masuoka, Ryuzo.

    1970-01-01

    When exchanging nuclear fuel assemblies during the operation of a nuclear reactor, melting of fuel bodies, and severence of tubular claddings is halted at the time of insertion by furnishing a neutron absorbing material such as B 10 , Cd, Gd or the like at the forward end of the fuel assembly to thereby lower the power peak at the forward ends of the fuel elements to within tolerable levels and thus prevent both fuel liquification and excessive expansion. The neutron absorbing material may be attached in the form of a plate to the fuel assembly forward tie plate, or may be inserted as a pellet into the front end of the tubular cladding. (Owens, K.J.)

  2. Nuclear fuel elements

    International Nuclear Information System (INIS)

    Ainsworth, K.F.

    1979-01-01

    A nuclear fuel element is described having a cluster of nuclear fuel pins supported in parallel, spaced apart relationship by transverse cellular braces within coaxial, inner and outer sleeves, the inner sleeve being in at least two separate axial lengths, each of the transverse braces having a peripheral portion which is clamped peripherally between the ends of the axial lengths of the inner sleeve. (author)

  3. Nuclear fuel manufacture

    International Nuclear Information System (INIS)

    Costello, J.M.

    1980-09-01

    The technologies used to manufacture nuclear fuel from uranium ore are outlined, with particular reference to the light water reactor fuel cycle. Capital and operating cost estimates for the processing stages are given, and the relevance to a developing uranium industry in Australia is discussed

  4. A disposal centre for immobilized nuclear waste

    International Nuclear Information System (INIS)

    1980-02-01

    This report describes a conceptual design of a disposal centre for immobilized nuclear waste. The surface facilities consist of plants for the preparation of steel cylinders containing nuclear waste immobilized in glass, shaft headframe buildings and all necessary support facilities. The underground disposal vault is located on one level at a depth of 1000 m. The waste cylinders are emplaced into boreholes in the tunnel floors. All surface and subsurface facilities are described, operations and schedules are summarized, and cost estimates and manpower requirements are given. (auth)

  5. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    Butterfield, C.E.; Waite, E.

    1982-01-01

    A nuclear reactor fuel element comprising a column of vibration compacted fuel which is retained in consolidated condition by a thimble shaped plug. The plug is wedged into gripping engagement with the wall of the sheath by a wedge. The wedge material has a lower coefficient of expansion than the sheath material so that at reactor operating temperature the retainer can relax sufficient to accommodate thermal expansion of the column of fuel. (author)

  6. Nuclear fuel element recovery using PEDSCO RMI Unit

    International Nuclear Information System (INIS)

    Martin, D.G.; Pedersen, B.V.

    1984-01-01

    In September 1982, a PEDSCO Remote Mobile Investigation Unit was used to recover damaged irradiated fuel elements from a fueling machine and trolley deck at Bruce Nuclear Generating Station 'A'. This Canadian-made remote controlled vehicle was originally designed for explosive ordinance disposal by law enforcement agencies. This paper describes its adaptation to nuclear service and its first mission, within a nuclear facility

  7. Nuclear fuel pellet loading apparatus

    International Nuclear Information System (INIS)

    Gerkey, K.S.

    1979-01-01

    An automatic apparatus for loading a predetermined amount of nuclear fuel pellets into a nuclear fuel element to be used in a nuclear reactor is described. The apparatus consists of a vibratory bed capable of supporting corrugated trays containing rows of nuclear fuel pellets and arranged in alignment with the open ends of several nuclear fuel elements. A sweep mechanism is arranged above the trays and serves to sweep the rows of fuel pellets onto the vibratory bed and into the fuel element. A length detecting system, in conjunction with a pellet stopping mechanism, is also provided to assure that a predetermined amount of nuclear fuel pellets are loaded into each fuel element

  8. Review Statement and Evaluation of the Swedish Nuclear Fuel and Waste Management Co's RDandD Programme 2004. Programme for Research, Development and Demonstration of Methods for the Management and Disposal of Nuclear Waste, including Social Science Research

    International Nuclear Information System (INIS)

    2005-12-01

    SKB has submitted RDandD Programme 2004 to SKI for review in accordance with the Act (1984:3) on Nuclear Activities. Based on SKI's review and the review statements received, SKI considers that: - SKB, and thereby the reactor owners, have fulfilled their obligations in accordance with paragraph 12 of the Act (1984:3) on Nuclear Activities, - Disposal in accordance with the KBS-3 concept seems to still be the most suitable way of disposing of spent nuclear fuel from the Swedish nuclear power programme. SKI would like to draw the Government's attention to the following evaluations and comments: - The question of who is responsible after the closure of a repository for spent nuclear fuel needs to be clarified. - SKB's plan of action is incomplete and its structure needs to be improved. The revised plan of action needs a more detailed account of the content of the basis for decision-making that SKB intends to present on different decision-making occasions. - As soon as possible, SKB should develop design premises for the canister and verify these premises in the next safety assessment which is planned for 2006. A clear and logical link between the detailed design premises for the canister and the requirements on long-term safety of the repository is still lacking. - SKB should specify the limits for different parameters that are of importance for the canister function. The account must be based on an identification of defects that can occur and their consequences for canister integrity and repository function. - SKB should clarify how the work on KBS-3H (horizontal deposition of the canisters) is to be developed. An estimate of how much time and resources will be required is needed in order to prepare a body of material corresponding to that for KBS-3V (vertical deposition which is, so far, the most studied concept). - SKB should continue to participate in and contribute to the development of methodology for safeguards in connection with the disposal process. The area

  9. Review Statement and Evaluation of the Swedish Nuclear Fuel and Waste Management Co's RDandD Programme 2004. Programme for Research, Development and Demonstration of Methods for the Management and Disposal of Nuclear Waste, including Social Science Research

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-12-15

    SKB has submitted RDandD Programme 2004 to SKI for review in accordance with the Act (1984:3) on Nuclear Activities. Based on SKI's review and the review statements received, SKI considers that: - SKB, and thereby the reactor owners, have fulfilled their obligations in accordance with paragraph 12 of the Act (1984:3) on Nuclear Activities, - Disposal in accordance with the KBS-3 concept seems to still be the most suitable way of disposing of spent nuclear fuel from the Swedish nuclear power programme. SKI would like to draw the Government's attention to the following evaluations and comments: - The question of who is responsible after the closure of a repository for spent nuclear fuel needs to be clarified. - SKB's plan of action is incomplete and its structure needs to be improved. The revised plan of action needs a more detailed account of the content of the basis for decision-making that SKB intends to present on different decision-making occasions. - As soon as possible, SKB should develop design premises for the canister and verify these premises in the next safety assessment which is planned for 2006. A clear and logical link between the detailed design premises for the canister and the requirements on long-term safety of the repository is still lacking. - SKB should specify the limits for different parameters that are of importance for the canister function. The account must be based on an identification of defects that can occur and their consequences for canister integrity and repository function. - SKB should clarify how the work on KBS-3H (horizontal deposition of the canisters) is to be developed. An estimate of how much time and resources will be required is needed in order to prepare a body of material corresponding to that for KBS-3V (vertical deposition which is, so far, the most studied concept). - SKB should continue to participate in and contribute to the development of methodology for safeguards in connection with the disposal process. The area

  10. Nuclear Fuel Cycle Objectives

    International Nuclear Information System (INIS)

    2013-01-01

    . The four Objectives publications include Nuclear General Objectives, Nuclear Power Objectives, Nuclear Fuel Cycle Objectives, and Radioactive Waste management and Decommissioning Objectives. This publication sets out the objectives that need to be achieved in the area of the nuclear fuel cycle to ensure that the Nuclear Energy Basic Principles are satisfied. Within each of these four Objectives publications, the individual topics that make up each area are addressed. The five topics included in this publication are: resources; fuel engineering and performance; spent fuel management and reprocessing; fuel cycles; and the research reactor nuclear fuel cycle

  11. Safety case for the disposal of spent nuclear fuel at Olkiluoto. Surface and near-surface hydrological modelling in the biosphere assessment BSA-2012

    International Nuclear Information System (INIS)

    Karvonen, T.

    2013-05-01

    The Finnish nuclear waste disposal company, Posiva Oy, is planning an underground repository for spent nuclear fuel to be constructed on the island of Olkiluoto on the south-west coast of Finland. This study is part of the biosphere assessment (BSA-2012) within the safety case for the repository. The surface hydrological modelling described in this report is aimed at providing link between radionuclide transport in the geosphere and in the biosphere systems. The SVAT-model and Olkiluoto site scale surface hydrological model were calibrated and validated in the present day conditions using the input data provided by the Olkiluoto Monitoring Programme (OMO). During the next 10 000 years the terrain and ecosystem development is to a large extent driven by the postglacial crustal uplift. UNTAMO is a GIS toolbox developed for simulating land-uplift driven or other changes in the biosphere. All the spatial and temporal input data (excluding meteorological data) needed in the surface hydrological modelling were provided by the UNTAMO toolbox. The specific outputs given by UNTAMO toolbox are time-dependent evolution of the biosphere objects. They are continuous and sufficiently homogeneous sub-areas of the modelled area that could potentially receive radionuclides released from the repository. Possible ecosystem types for biosphere objects are coast, lake, river, forest, cropland, pasture and wetland. The primary goal of this study was to compute vertical and horizontal water fluxes in the biosphere objects. These data will be used in the biosphere radionuclide transport calculations. The method adopted here is based on calculating average vertical and horizontal fluxes for biosphere objects from the results of the full 3D-model. It was not necessary to develop any simplified hydrological model for the biosphere objects. This report includes modelling results from for the Reference Case (present day climate) and Terr M axAgri Case (maximum extent of agricultural areas and

  12. Spent fuel waste disposal: analyses of model uncertainty in the MICADO project

    International Nuclear Information System (INIS)

    Grambow, B.; Ferry, C.; Casas, I.; Bruno, J.; Quinones, J.; Johnson, L.

    2010-01-01

    The objective was to find out whether international research has now provided sufficiently reliable models to assess the corrosion behavior of spent fuel in groundwater and by this to contribute to answering the question whether the highly radioactive used fuel from nuclear reactors can be disposed of safely in a geological repository. Principal project results are described in the paper

  13. Performance assessment of the direct disposal in unsaturated tuff of spent nuclear fuel and high-level waste owned by U.S. Department of Energy. Volume 1: Executive summary

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [ed.] [Sandia National Labs., Albuquerque, NM (United States). WIPP Performance Assessment Dept.

    1995-03-01

    This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservation. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2,100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9,200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM. A source term model was developed to study the wide variety of waste forms, which included radionuclides residing in 10 different matrices and up to 8 nested layers of material that might react with water. The possibility and consequences of critical conditions occurring in or near containers of highly enriched uranium spent nuclear fuel were also studied.