Potential role of ABC-assisted repositories in U.S. plutonium and high-level waste disposition

Energy Technology Data Exchange (ETDEWEB)

Berwald, D.; Favale, A.; Myers, T. [Grumman Aerospace Corporation, Bethpage, NY (United States)] [and others

1995-10-01

This paper characterizes the issues involving deep geologic disposal of LWR spent fuel rods, then presents results of an investigation to quantify the potential role of Accelerator-Based Conversion (ABC) in an integrated national nuclear materials and high level waste disposition strategy. The investigation used the deep geological repository envisioned for Yucca Mt., Nevada as a baseline and considered complementary roles for integrated ABC transmutation systems. The results indicate that although a U.S. geologic waste repository will continue to be required, waste partitioning and accelerator transmutation of plutonium, the minor actinides, and selected long-lived fission products can result in the following substantial benefits: plutonium burndown to near zero levels, a dramatic reduction of the long term hazard associated with geologic repositories, an ability to place several-fold more high level nuclear waste in a single repository, electricity sales to compensate for capital and operating costs.

Chemotoxic materials in a final repository for high-level radioactive wastes. CHEMOTOX concept for defence in depth concerning ground water protection from chemotoxic materials in a final high-level waste repository

International Nuclear Information System (INIS)

Alt, Stefan; Sailer, Michael; Schmidt, Gerhard; Herbert, Horst-Juergen; Krone, Juergen; Tholen, Marion

2009-01-01

The disposal of high-level radioactive wastes in a final repository includes chemotoxic materials. The chemotoxic materials are either part of the radioactive material or part of the packaging material, or the structures within the repository. In the frame of the licensing procedure it has to be demonstrated that no hazardous pollution of the ground water or other disadvantageous changes can occur. The report describes the common project of the Oeko-Institut e.V., the DBE Technology GmbH and the GRS mbH concerning the possible demonstration of a systematic protection of the groundwater against chemotoxic materials in case of a final high-level-radioactive waste repository in the host materials salt and clay stone.

Natural geochemical analogues of the near field of high-level nuclear waste repositories

International Nuclear Information System (INIS)

Apps, J.A.

1995-01-01

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

Low level waste repositories

International Nuclear Information System (INIS)

Hill, P.R.H.; Wilson, M.A.

1983-11-01

Factors in selecting a site for low-level radioactive waste disposal are discussed. South Australia has used a former tailings dam in a remote, arid location as a llw repository. There are also low-level waste disposal procedures at the Olympic Dam copper/uranium project

The function of packing materials in a high-level nuclear waste repository and some candidate materials: Salt Repository Project

International Nuclear Information System (INIS)

Bunnell, L.R.; Shade, J.W.

1987-03-01

Packing materials should be included in waste package design for a high-level nuclear waste repository in salt. A packing material barrier would increase confidence in the waste package by alleviating possible shortcomings in the present design and prolonging confinement capabilities. Packing materials have been studied for uses in other geologic repositories; appropriately chosen, they would enhance the confinement capabilities of salt repository waste packages in several ways. Benefits of packing materials include retarding or chemically modifying brines to reduce corrosion of the waste package, providing good thermal conductivity between the waste package and host rock, retarding or absorbing radionuclides, and reducing the massiveness of the waste package. These benefits are available at low percentage of total repository cost, if the packing material is properly chosen and used. Several candidate materials are being considered, including oxides, hydroxides, silicates, cement-based mixtures, and clay mixtures. 18 refs

Source term evaluation model for high-level radioactive waste repository with decay chain build-up.

Science.gov (United States)

Chopra, Manish; Sunny, Faby; Oza, R B

2016-09-18

A source term model based on two-component leach flux concept is developed for a high-level radioactive waste repository. The long-lived radionuclides associated with high-level waste may give rise to the build-up of activity because of radioactive decay chains. The ingrowths of progeny are incorporated in the model using Bateman decay chain build-up equations. The model is applied to different radionuclides present in the high-level radioactive waste, which form a part of decay chains (4n to 4n + 3 series), and the activity of the parent and daughter radionuclides leaching out of the waste matrix is estimated. Two cases are considered: one when only parent is present initially in the waste and another where daughters are also initially present in the waste matrix. The incorporation of in situ production of daughter radionuclides in the source is important to carry out realistic estimates. It is shown that the inclusion of decay chain build-up is essential to avoid underestimation of the radiological impact assessment of the repository. The model can be a useful tool for evaluating the source term of the radionuclide transport models used for the radiological impact assessment of high-level radioactive waste repositories.

Testing of high-level waste forms under repository conditions

International Nuclear Information System (INIS)

Mc Menamin, T.

1989-01-01

The workshop on testing of high-level waste forms under repository conditions was held on 17 to 21 October 1988 in Cadarache, France, and sponsored by the Commission of the European Communities (CEC), the Commissariat a l'energie atomique (CEA) and the Savannah River Laboratory (US DOE). Participants included representatives from Australia, Belgium, Denmark, France, Germany, Italy, Japan, the Netherlands, Sweden, Switzerland, The United Kingdom and the United States. The first part of the conference featured a workshop on in situ testing of simulated nuclear waste forms and proposed package components, with an emphasis on the materials interface interactions tests (MIIT). MIIT is a sevent-part programme that involves field testing of 15 glass and waste form systems supplied by seven countries, along with potential canister and overpack materials as well as geologic samples, in the salt geology at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, New Mexico, USA. This effort is still in progress and these proceedings document studies and findings obtained thus far. The second part of the meeting emphasized multinational experimental studies and results derived from repository systems simulation tests (RSST), which were performed in granite, clay and salt environments

Project Guarantee 1985. Final repository for high-level radioactive wastes: The system of safety barriers

International Nuclear Information System (INIS)

Anon.

1985-01-01

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

Evaluation of health and safety impacts of defense high-level waste in geologic repositories

International Nuclear Information System (INIS)

Smith, E.D.; Kocher, D.C.; Witherspoon, J.P.

1985-02-01

Pursuant to the requirement of the Nuclear Waste Policy Act of 1982 that the President evaluate the use of commercial high-level waste repositories for the disposal of defense high-level wastes, a comparative assessment has been performed of the potential health and safety impacts of disposal of defense wastes in commercial or defense-only repositories. Simplified models were used to make quantitative estimates of both long- and short-term health and safety impacts of several options for defense high-level waste disposal. The results indicate that potential health and safety impacts are not likely to vary significantly among the different disposal options for defense wastes. Estimated long-term health and safety impacts from all defense-waste disposal options are somewhat less than those from commercial waste disposal, while short-term health and safety impacts appear to be insensitive to the differences between defense and commercial wastes. In all cases, potential health and safety impacts are small because of the need to meet stringent standards promulgated by the US Environmental Protection Agency and the US Nuclear Regulatory Commission. We conclude that health and safety impacts should not be a significant factor in the choice of a disposal option for defense high-level wastes. 20 references, 14 tables

Selection of the host rock for high level radioactive waste repository in China

International Nuclear Information System (INIS)

Jin Yuanxin; Wang Wenguang; Chen Zhangru

2001-01-01

The authors has briefly introduced the experiences of the host rock selection and the host rock types in other countries for high level radioactive waste repository. The potential host rocks in China are investigated. They include granite, tuff, clay, basalt, salt, and loess. The report has expounded the distributions, scale, thickness, mineral and chemical composition, construction, petrogenesis and the ages of the rock. The possibility of these rocks as the host rock has been studied. The six pieces of distribution map of potential rocks have been made up. Through the synthetical study, it is considered that granite as the host rock of high level radioactive waste repository is possible

Fuzzy distributions in probabilistic environmental impact assessment: application to a high-level waste repository

International Nuclear Information System (INIS)

Datta, D.; Joshi, M.L.

2006-01-01

Environmental modeling with a satisfaction levels of the end user in relation to a defined parameter coupled with imprecision that stems from the field data is a key issue. In the context of this issue success of possibility theory based on fuzzy sets has high visibility in comparison with conventional probability theory. Environmental impact assessments of a high level waste repository is focused using the new approach because the problems under consideration includes a number of qualitative uncertainties at different levels, apart from being quite complex; decision-maker's need to have a transparent assessment result that will enable him to understand underlying assumptions and to judge resulting doses. Fuzzy distributions have been tried to resolve the issues related to the safety of environment from the waste repository. Paper describes the details of fuzzy distribution, fuzzy logic and its possible application to deal the qualitative and quantitative uncertainty in connection with waste repository. (author)

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

International Nuclear Information System (INIS)

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

1987-01-01

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

Symposium on the development of nuclear waste policy: Siting the high-level nuclear waste repository

International Nuclear Information System (INIS)

Pijawka, K.D.; Mushkatel, A.H.

1991-01-01

The Nuclear Waste Policy Act of 1982 (NWPA) attempted to formulate a viable national policy for managing the disposal of high-level nuclear wastes. The NWPA authorized the selection of two repository sites: the first to be constructed in the West and a second site developed in the eastern United States. A detailed process for site selection was outlined in the NWPA. In addition, the NWPA authorized open-quotes the development of a waste transportation system; required the Department of Energy (DOE) to submit a proposal to construct a facility for monitored retrievable storage (MRS) after conducting a study of the need for, and feasibility of such a facility; and required the President to evaluate the use of the repositories ... for the disposal of high-level waste resulting from defense activitiesclose quotes (DOE, 1988, p. 1). A series of provisions granting oversight participation to states and Indian tribes, as well as a compensation package for the ultimate host state were also included. Responsibility for implementing the NWPA was assigned to DOE

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

Energy Technology Data Exchange (ETDEWEB)

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

1982-12-01

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

Source terms for analysis of accidents at a high level waste repository

International Nuclear Information System (INIS)

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

1989-01-01

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

Application of GIS in siting disposal repository for high level radioactive waste

International Nuclear Information System (INIS)

Zhong Xia; Wang Ju; Huang Shutao

2010-01-01

High level radioactive waste geo-disposal is directly related to environment protection and Sustainable Utilization of nuclear energy. To ensure both success and long-term safe disposal of the high level-radioactive waste, finding suitable sites is an important step in the research. Meanwhile, siting and evaluation the geo-disposal repository for high level-radioactive waste need a wide range of relevant information, including geology and geophysical surveys data, geochemistry data and other geoscience data in the field. At the same time, some of the data has its spatial property. Geographic information system (GIS) have a role to play in all geographic and spatial aspects of the development and management of the siting disposal repository. GIS has greatly enhanced our ability to store, analyze and communicate accounts of the information. This study was conducted to compare the more suitable sites for the repository using GIS -based on the data which belongs to the preselected area in BeiShan, Gansu Province, China. First, the data of the pre-selected site is captured by GIS and stored in the geoscience database. Then, according to the relevant guide line in the field, the analysis models based on GIS are build. There are some thematic layers of the sites character grouped into two basic type, namely social factors(town, traffic and nuclear plant) and natural factors (water, land and animals and plants).In the paper, a series of GIS models was developed to compare the pre-selected areas in order to make optimal decision. This study shows that with appropriate and enough information GIS used in modeling is a powerful tool for site selection for disposal repository. (authors)

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

International Nuclear Information System (INIS)

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

1987-01-01

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

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

International Nuclear Information System (INIS)

1978-01-01

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

Research on high level radioactive waste repository seismic design criteria

International Nuclear Information System (INIS)

Jing Xu

2012-01-01

Review seismic hazard analysis principle and method in site suitable assessment process of Yucca Mountain Project, and seismic design criteria and seismic design basis in primary design process. Demonstrated spatial character of seismic hazard by calculated regional seismic hazard map. Contrasted different level seismic design basis to show their differences and relation. Discussed seismic design criteria for preclosure phrase of high level waste repository and preference goal under beyond design basis ground motion. (author)

Disruption scenarios for a high-level waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Ross, B.

1986-01-01

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

High level radioactive waste repositories. Task 3. Review of underground handling and emplacement. 1. Executive summary

Energy Technology Data Exchange (ETDEWEB)

1981-01-01

A review is presented of proposals for transport, handling and emplacement of high-level radioactive waste in an underground repository appropriate to the U.K. context, with particular reference to waste block size and configuration; self-shielded or partially-shielded block; stages of disposal; transport by road/rail to repository site; handling techniques within repository; emplacement in vertical holes or horizontal tunnels; repository access by adit, incline or shaft; conventional and radiological safety; costs; and major areas of uncertainty requiring research or development.

Synthetic hydrogeological study on Beishan preselected area for high-level radioactive waste repository in China

International Nuclear Information System (INIS)

Guo Yonghai; Su Rui; Ji Ruili; Wang Hailong; Liu Shufen; Zong Zihua; Dong Jiannan; Zhang Ming

2014-01-01

On the basis of large scale field hydrogeological investigation, synthetic hydrogeological studies related to groundwater system characteristics, permeability of rock bodies, groundwater dynamic, hydrogeochemistry, isotopic hydrology, CFC's of groundwater and groundwater flow field simulation were carried out for Beishan area, Gansu province. According to analysis on a large amount of hydrogeological data, the characteristics of groundwater circulation, groundwater hydrodynamics and hydrgeochemistry were described and the suitability of Beishan area as the potential area of high-level radioactive waste disposal was evaluated in the paper. Through this study, the hydrogeological study and evaluation methods in the siting of China's high level radioactive waste repository were set up. Furthermore, the important hydrogeological scientific evidence was provided for optimal site filtration of China's high-level radioactive waste repository in Beishan area. (authors)

Siting the high level radioactive waste repository in the United States

International Nuclear Information System (INIS)

Tourtellotte, J.

1992-01-01

For more than twenty-five years after the National Academy of Science issued its 1957 report recommending a Mined Geologic Disposal System (''MGDS'') for high level radioactive waste, no substantial progress was made in selecting and siting a repository. The United States Congress attempted to give substantive and procedural direction to the program in the Nuclear Waste Policy Act of 1982. Seeing that very little had been accomplished some five years later, Congress gave further direction and tentatively selected a single site, Yucca Mountain in Nevada, in the Nuclear Waste Policy Act Amendments of 1987. Selection of the Yucca Mountain site created a political conflict between federal and state authorities. Until recently, that conflict stalled the site characterization and evaluation program. Standards development under a polycentric regulatory regime has also been slow and has created a number of technical, legal and policy controversies. The Environmental Protection Agency (EPA), charged with setting radiation protection rules, may be developing regulatory standards which are technically unachievable and, therefore, legally unprovable in a licensing proceeding. The Nuclear Regulatory Commission (NRC), having the responsibility for licensing and setting performance objectives, may be taking an overly conservative approach. This approach could seriously impact the cost and may preclude the ability to reach an affirmative finding on license issuance. The Department of Energy (DOE) has responsibility for siting, construction and operation of the repository. In so doing, DOE must apply both EPA and NRC standards. To the extent that EPA and NRC standards are untimely, poorly defined, unrealistic, inconsistent, and technically or legally unsound, DOE may be forestalled from fulfilling its responsibilities. The US must rethink its approach to siting the high level radioactive waste repository and take realistic, timely action to preserve the nuclear option. (Author)

Effects of post-disposal gas generation in a repository for spent fuel, high-level waste and long-lived intermediate level waste sited in opalinus clay

International Nuclear Information System (INIS)

Johnson, L.; Marschall, P.; Zuidema, P.; Gribi, P.

2004-07-01

This comprehensive report issued by the Swiss National Cooperative for the Disposal of Radioactive Waste NAGRA takes a look at post-disposal gas generation in a repository for spent fuel and highly radioactive wastes in Opalinus clay strata. This study provides a comprehensive treatment of the issue of gas generation in a repository for spent fuel (SF), vitrified high-level waste (HLW) and long-lived intermediate-level waste (ILW), sited in the Opalinus clay of the Zuercher Weinland in northern Switzerland. The issue of how gas generation in and transport from waste repositories may influence disposal system performance has been under study for many years, both at Nagra and internationally. The report consists of three main parts: (i) A synthesis of basic information on the host rock and on details of repository construction; (ii) A discussion on gas transport characteristics of the engineered barrier system and the geosphere; (iii) A discussion on the effects of gas on system performance, based on the available information on gas generation, gas transport properties and gas pathways provided in the previous parts of the report. Simplified model calculations based on a mass balance approach for the gas generated within the repository are presented and discussed

System analysis methods for geological repository of high level radioactive waste in granite

International Nuclear Information System (INIS)

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

2009-01-01

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

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

International Nuclear Information System (INIS)

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

1980-01-01

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

Environmental program overview for a high-level radioactive waste repository at Yucca Mountain

International Nuclear Information System (INIS)

1988-12-01

The United States plans to begin operating the first repository for the permanent disposal of high-level nuclear waste early in the next century. In February 1983, the US Department of Energy (DOE) identified Yucca Mountain, in Nevada, as one of nine potentially acceptable sites for a repository. To determine its suitability, the DOE evaluated the Yucca Mountain site, along with eight other potentially acceptable sites, in accordance with the DOE's General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories. The purpose of the Environmental Program Overview (EPO) for the Yucca Mountain site is to provide an overview of the overall, comprehensive approach being used to satisfy the environmental requirements applicable to sitting a repository at Yucca Mountain. The EPO states how the DOE will address the following environmental areas: aesthetics, air quality, cultural resources (archaeological and Native American components), noise, radiological studies, soils, terrestrial ecosystems, and water resources. This EPO describes the environmental program being developed for the sitting of a repository at Yucca Mountain. 1 fig., 3 tabs

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

Energy Technology Data Exchange (ETDEWEB)

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

1981-12-01

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

Hydrological performance assessment on siting the high level radioactive waste repository

International Nuclear Information System (INIS)

Guo Yonghai; Liu Shufen; Wang Ju; Wang Zhiming; Su Rui; Lv Chuanhe; Zong Zihua

2007-01-01

Based on the research experiences in China and some developed countries in the world, the processes and methods on hydrological performance assessment for the siting of high radioactive repository are discussed in this paper. The methods and contents of hydrological performance assessment are discussed respectively for region, area and site hydrological investigation stages. At the same time, the hydrological performance assessment of the potential site for high level radioactive waste in China is introduced. (authors)

Total system performance predictions (TSPA-1995) for the potential high-level waste repository at Yucca Mountain

International Nuclear Information System (INIS)

Sevougian, S.D.; Andrews, R.W.; McNeish, J.A.

1996-01-01

The management and operating contractor for the potential high-level nuclear waste repository at Yucca Mountain, Nevada, has been recently completed a new performance assessment of the ability of the repository to isolate and contain nuclear waste for long time periods (up to 1,000,000 years). Sensitivity analyses determine the most important physical parameters and processes, using the most current information and models

Thermoelastic analysis of spent fuel and high level radioactive waste repositories in salt. A semi-analytical solution

International Nuclear Information System (INIS)

St John, C.M.

1977-04-01

An underground repository containing heat generating, High Level Waste or Spent Unreprocessed Fuel may be approximated as a finite number of heat sources distributed across the plane of the repository. The resulting temperature, displacement and stress changes may be calculated using analytical solutions, providing linear thermoelasticity is assumed. This report documents a computer program based on this approach and gives results that form the basis for a comparison between the effects of disposing of High Level Waste and Spent Unreprocessed Fuel

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

International Nuclear Information System (INIS)

Kovanda, O.

2017-01-01

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

Preliminary site characterization at Beishan northwest China-A potential site for China's high-level radioactive waste repository

International Nuclear Information System (INIS)

Wang Ju; Su Rui; Xue Weiming; Zheng Hualing

2004-01-01

Chinese nuclear power plants,radioactive waste and radioactive waste disposal are introduced. Beishan region (Gansu province,Northwest China)for high-level radioactive waste repository and preliminary site characterization are also introduced. (Zhang chao)

Coupled thermo-mechanical analysis of granite for high-level radioactive waste repository

International Nuclear Information System (INIS)

Liu Wengang; Wang Ju; Zhou Hongwei; Jiang Pengfei; Yang Chunhe

2008-01-01

High-level radioactive wastes (HLW) repository is a special deep underground engineering, and in the stages of site selection, designing, constructing ,the stability evaluation, lots of important rock mechanics problems need to be resolved. During the decay of nuclear waste, enormous thermal energy was released and temperature variation caused dynamic distribution of stress and deformation field of surrounding rock of repository. BeiShan region of Gansu province was selected to be the repository field in the future, it is of practical significance to do research on granite in this region. Based on the concept model of HLW repository, this thesis calculates temperature field, stress field and deformation field of HLW repository surrounding rock under the condition of TM coupled with applying the finite difference FLAC 3D . From this study, thermo-mechanical characteristic of granite is obtained primarily under given canister heat source and given decay law function. And these results show that the reasonable space between disposal hole is 8 m-12 m, and the peak temperature of the canister surface is 130 ℃, the centerline temperature between pits is about 40 ℃ which is maintained for about hundreds of years under given heating output at -500 m depth. (authors)

Workshops for state review of site suitability criteria for high-level radioactive waste repositories: analysis and recommendations

International Nuclear Information System (INIS)

1978-02-01

The purpose of this report is to present the views and recommendations of invited State officials and legislators participating in a workshop concerned with preliminary site suitability criteria for high level radioactive waste repositories. The workshops were open to the public and were conducted by the U. S. Nuclear Regulatory Commission (NRC) during September 1977 in three regional locations across the United States. This contractor report is the second of two reports and consolidates the discussion by State officials on the role of a State in siting a repository, NRC's waste management program, the transportation of high level wastes, the number and location of repositories and concerns with the socio-economic impacts of siting a repository in a community. The recommendations to the NRC can be categorized into four areas. These were: (1) general recommendations, (2) procedural recommendations, (3) recommendations for improving communications, and (4) specific recommendations on the preliminary siting criteria. The recommendations emphasized the need for early State involvement in the siting process, the need for an impacted State to assess repository operations, the need for early solution of waste transportation concerns, and the requirement that any repository developed insure the protection of the public health and safety as its most important characteristic. Other participant recommendations are included in the body of the report

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

International Nuclear Information System (INIS)

Perkins, C.

2001-01-01

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

Numerical method for analysis of temperature rises and thermal stresses around high level radioactive waste repository in granite

International Nuclear Information System (INIS)

Shimooka, Hiroshi

1982-01-01

The disposal of high-level radioactive waste should result in temperature rises and thermal stresses which change the hydraulic conductivity of the rock around the repository. For safety analysis on disposal of high-level radioactive waste into hard rock, it is necessary to find the temperature rises and thermal stresses distributions around the repository. In this paper, these distribution changes are analyzed by the use of the finite difference method. In advance of numerical analysis, it is required to simplify the shapes and properties of the repository and the rock. Several kinds of numerical models are prepared, and the results of this analysis are examined. And, the waste disposal methods are discussed from the stand-points of the temperature rise and thermal stress analysis. (author)

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

International Nuclear Information System (INIS)

Forsberg, C.W.

1993-01-01

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

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

International Nuclear Information System (INIS)

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

1983-11-01

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

Public opposition to the siting of the high-level nuclear waste repository: The importance of trust

International Nuclear Information System (INIS)

Pijawka, K.D.; Mushkatel, A.H.

1991-01-01

This paper examines several dimensions of public opposition to the proposed siting of the high-level nuclear waste repository at Yucca Mountain. In order to provide a context for the public's views of the repository in metropolitan Clark County, both governmental studies of the repository siting process are analyzed, as well as elements of the Nuclear Waste Policy Act. This analysis suggests that one potentially key component of the public's opposition to the siting, as well as their perceptions of risk of the facility, may be the result of a lack of trust in the Department of Energy. Empirical analysis of survey data collected in Nevada in 1988 confirms the strong relationship between political trust and repository risk perceptions

Aspects on the gas generation and migration in repositories for high level waste in salt formations

International Nuclear Information System (INIS)

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

2013-07-01

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

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

International Nuclear Information System (INIS)

Wang Changxuan; Liu Xiaodong; Liu Pinghui

2008-01-01

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

Analogues to features and processes of a high-level radioactive waste repository proposed for Yucca Mountain, Nevada

Science.gov (United States)

Simmons, Ardyth M.; Stuckless, John S.; with a Foreword by Abraham Van Luik, U.S. Department of Energy

2010-01-01

Natural analogues are defined for this report as naturally occurring or anthropogenic systems in which processes similar to those expected to occur in a nuclear waste repository are thought to have taken place over time periods of decades to millennia and on spatial scales as much as tens of kilometers. Analogues provide an important temporal and spatial dimension that cannot be tested by laboratory or field-scale experiments. Analogues provide one of the multiple lines of evidence intended to increase confidence in the safe geologic disposal of high-level radioactive waste. Although the work in this report was completed specifically for Yucca Mountain, Nevada, as the proposed geologic repository for high-level radioactive waste under the U.S. Nuclear Waste Policy Act, the applicability of the science, analyses, and interpretations is not limited to a specific site. Natural and anthropogenic analogues have provided and can continue to provide value in understanding features and processes of importance across a wide variety of topics in addressing the challenges of geologic isolation of radioactive waste and also as a contribution to scientific investigations unrelated to waste disposal. Isolation of radioactive waste at a mined geologic repository would be through a combination of natural features and engineered barriers. In this report we examine analogues to many of the various components of the Yucca Mountain system, including the preservation of materials in unsaturated environments, flow of water through unsaturated volcanic tuff, seepage into repository drifts, repository drift stability, stability and alteration of waste forms and components of the engineered barrier system, and transport of radionuclides through unsaturated and saturated rock zones.

International perspective on repositories for low level waste

International Nuclear Information System (INIS)

Bergstroem, Ulla; Pers, Karin; Almen, Ylva

2011-12-01

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

International perspective on repositories for low level waste

Energy Technology Data Exchange (ETDEWEB)

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

2011-12-15

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

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

International Nuclear Information System (INIS)

Klingsberg, C.; Duguid, J.

1980-10-01

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

Long-Term Waste Package Degradation Studies at the Yucca Mountain Potential High-Level Nuclear Waste Repository

International Nuclear Information System (INIS)

Mon, K. G.; Bullard, B. E.; Longsine, D. E.; Mehta, S.; Lee, J. H.; Monib, A. M.

2002-01-01

The Site Recommendation (SR) process for the potential repository for spent nuclear fuel (SNF) and high-level nuclear waste (HLW) at Yucca Mountain, Nevada is underway. Fulfillment of the requirements for substantially complete containment of the radioactive waste emplaced in the potential repository and subsequent slow release of radionuclides from the Engineered Barrier System (EBS) into the geosphere will rely on a robust waste container design, among other EBS components. Part of the SR process involves sensitivity studies aimed at elucidating which model parameters contribute most to the drip shield and waste package degradation characteristics. The model parameters identified included (a) general corrosion rate model parameters (temperature-dependence and uncertainty treatment), and (b) stress corrosion cracking (SCC) model parameters (uncertainty treatment of stress and stress intensity factor profiles in the Alloy 22 waste package outer barrier closure weld regions, the SCC initiation stress threshold, and the fraction of manufacturing flaws oriented favorably for through-wall penetration by SCC). These model parameters were reevaluated and new distributions were generated. Also, early waste package failures due to improper heat treatment were added to the waste package degradation model. The results of these investigations indicate that the waste package failure profiles are governed by the manufacturing flaw orientation model parameters and models used

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

International Nuclear Information System (INIS)

1984-11-01

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

A conceptual subsurface facility design for a high-level nuclear waste repository at Yucca Mountain

International Nuclear Information System (INIS)

McKenzie, D.G., III; Bhattacharyya, K.K.; Segrest, A.M.

1996-01-01

The US Department of Energy is responsible for the design, construction, operation and closure of a repository in which to permanently dispose of the nation's high level nuclear waste. In addition to the objective of safely isolating the waste inventory, the repository must provide a safe working environment for its workforce, and protect the public. The conceptual design for this facility is currently being developed. Tunnel Boring Machine will be used to excavate 228 kilometers of tunneling to construct the facility over a 30 year period. The excavation operations will be physically separated from the waste emplacement operations, and each operation will have its own dedicated ventilation system. The facility is being designed to remain open for 150 years

Long-term stability of the near-field about high-level radioactive waste repository in thermo-hydro-mechanical coupling action condition

International Nuclear Information System (INIS)

Liu Yuemiao; Wang Ju; Ke Dan; Cai Meifeng

2008-01-01

It is a long-term process for the high-level radioactive waste repository, from opening, construction to end of its service. The long-term stability of the near-field is the key issue for the design of HLW repository because the opening and heat generated from the HLW. Through a nationwide investigation, Beishan area, a Gobi desert in Gansu province, is considered as a suitable candidate and GMZ bentonite deposit which located in Xinghe County, Inner Mongolia has been proposed for the supplier of buffer/backfill material for HLW geological repository in China. According to the R and D guide of high-level radioactive waste disposal in China, the 3D model of HLW repository with high-level radioactive waste, canister and buffer/backfill material is established using FLAC3D. To take into account in situ stress, geothermal gradient, groundwater, thermal relief of HLW and swelling pressure of buffer/backfill material, the evolution of temperature, stress and displacement of HLW repository under thermo-mechanical coupling, hydro-mechanical coupling and thermo-hydro-mechanical coupling conditions was analyzed respectively. The long-term stability of HLW repository in Beishan area was studied. (authors)

Anticipated Degradation Modes of Metallic Engineered Barriers for High-Level Nuclear Waste Repositories

Science.gov (United States)

Rodríguez, Martín A.

2014-03-01

Metallic engineered barriers must provide a period of absolute containment to high-level radioactive waste in geological repositories. Candidate materials include copper alloys, carbon steels, stainless steels, nickel alloys, and titanium alloys. The national programs of nuclear waste management have to identify and assess the anticipated degradation modes of the selected materials in the corresponding repository environment, which evolves in time. Commonly assessed degradation modes include general corrosion, localized corrosion, stress-corrosion cracking, hydrogen-assisted cracking, and microbiologically influenced corrosion. Laboratory testing and modeling in metallurgical and environmental conditions of similar and higher aggressiveness than those expected in service conditions are used to evaluate the corrosion resistance of the materials. This review focuses on the anticipated degradation modes of the selected or reference materials as corrosion-resistant barriers in nuclear repositories. These degradation modes depend not only on the selected alloy but also on the near-field environment. The evolution of the near-field environment varies for saturated and unsaturated repositories considering backfilled and unbackfilled conditions. In saturated repositories, localized corrosion and stress-corrosion cracking may occur in the initial aerobic stage, while general corrosion and hydrogen-assisted cracking are the main degradation modes in the anaerobic stage. Unsaturated repositories would provide an oxidizing environment during the entire repository lifetime. Microbiologically influenced corrosion may be avoided or minimized by selecting an appropriate backfill material. Radiation effects are negligible provided that a thick-walled container or an inner shielding container is used.

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

International Nuclear Information System (INIS)

Perkins, C.

2003-01-01

The Australian Government is committed to establishing two purpose-built facilities for the management of Australia's radioactive waste; the national repository for disposal of low level and short-lived intermediate level ('low level') waste, and the national store for storage of long-lived intermediate level ('intermediate level') waste. It is strongly in the interests of public security and safety to secure radioactive waste by disposal or storage in facilities specially designed for this purpose. The current arrangements where waste is stored under ad hoc arrangements at hundreds of sites around Australia does not represent international best practice in radioactive waste management. Environmental approval has been obtained for the national repository to be located at Site 40a, 20 km east of Woomera in South Australia, and licences are currently being sought from the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) to site, construct and operate the facility. The national repository may be operating in 2004 subject to obtaining the required licences. The national store will be located on Australian Government land and house intermediate level waste produced by Australian Government departments and agencies. The national store will not be located in South Australia. Short-listing of potentially suitable sites is expected to be completed soon

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

International Nuclear Information System (INIS)

1977-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

1977-01-01

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

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

International Nuclear Information System (INIS)

1977-06-01

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

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

Energy Technology Data Exchange (ETDEWEB)

1977-06-01

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

Environmental remediation of high-level nuclear waste in geological repository. Modified computer code creates ultimate benchmark in natural systems

International Nuclear Information System (INIS)

Peter, Geoffrey J.

2011-01-01

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

Siting high-level nuclear waste repositories: A progress report for Rhode Island

International Nuclear Information System (INIS)

Frohlich, R.K.; Vild, B.F.

1986-03-01

In this booklet, we will not try to argue the pros and cons of nuclear power or weapons production. We will focus instead on the issue of nuclear waste disposal. With the passage of the Nuclear Waste Policy Act (NWPA) of 1982, the US Congress and the President charged federal and state regulators with the responsibility of settling that issue by the end of this century - with extensive public involvement. This booklet, now in its second printing, is designed to explain the nature of ''high-level'' nuclear waste, the essential criteria for its safe and permanent disposal, and Rhode Island's participation in the federal repository program. It has been funded from a USDOE grant derived from a utility-financed Nuclear Waste Fund established under the NWPA. 17 refs., 10 figs., 2 tabs

Attitudes and opposition in siting a high level nuclear waste repository

International Nuclear Information System (INIS)

Sjoeberg, L.; Viklund, M.; Truedsson, J.

1998-09-01

In Sweden, the Swedish Nuclear Fuel and Waste Management Company (SKB) handles all issues concerning nuclear waste, including the siting process, in which the final outcome is intended to be a repository for high level nuclear waste placed deep down in bedrock. The main objective of the siting process is to find a host community fulfilling two important conditions: the safety demands have been met and agreements with the municipality can be accomplished. Only in such municipalities, so-called feasibility studies will be conducted. After conducting general studies in the whole country, SKB, in October 1992, sent letters with information about the intended feasibility studies to all Swedish municipalities. As a result, feasibility studies are or have been considered - and in some cases also been conducted - in eleven Swedish municipalities up until 1998. These are the municipalities where the attitudes and opposition towards a feasibility study, and possibly a final repository, are studied. The discussion can be divided into three main parts: Management of the siting process; Inherent 'chaotic' processes and/or factors and risk perception. It is argued that two important problems could have been avoided at least partly: The citizens in many municipalities were uncertain of the relationship between a feasibility study and a final repository, and in many municipalities the citizens were afraid that the Government could overrule the municipal veto. Because of these fears, a common argument among the opponents of a feasibility study was: 'to be sure of not receiving a final repository, we say no to a feasibility study'. Some inherent factors, more or less prevalent in the municipalities as well as in society in general, may also partly explain the outcome of the siting process. The municipalities in which the debate has been heated, and where public support has been more difficult to reach, share some common characteristics. Esp. in the municipalities in the north of

Attitudes and opposition in siting a high level nuclear waste repository

Energy Technology Data Exchange (ETDEWEB)

Sjoeberg, L.; Viklund, M.; Truedsson, J

1998-09-01

In Sweden, the Swedish Nuclear Fuel and Waste Management Company (SKB) handles all issues concerning nuclear waste, including the siting process, in which the final outcome is intended to be a repository for high level nuclear waste placed deep down in bedrock. The main objective of the siting process is to find a host community fulfilling two important conditions: the safety demands have been met and agreements with the municipality can be accomplished. Only in such municipalities, so-called feasibility studies will be conducted. After conducting general studies in the whole country, SKB, in October 1992, sent letters with information about the intended feasibility studies to all Swedish municipalities. As a result, feasibility studies are or have been considered - and in some cases also been conducted - in eleven Swedish municipalities up until 1998. These are the municipalities where the attitudes and opposition towards a feasibility study, and possibly a final repository, are studied. The discussion can be divided into three main parts: Management of the siting process; Inherent `chaotic` processes and/or factors and risk perception. It is argued that two important problems could have been avoided at least partly: The citizens in many municipalities were uncertain of the relationship between a feasibility study and a final repository, and in many municipalities the citizens were afraid that the Government could overrule the municipal veto. Because of these fears, a common argument among the opponents of a feasibility study was: `to be sure of not receiving a final repository, we say no to a feasibility study`. Some inherent factors, more or less prevalent in the municipalities as well as in society in general, may also partly explain the outcome of the siting process. The municipalities in which the debate has been heated, and where public support has been more difficult to reach, share some common characteristics. Esp. in the municipalities in the north of

High-level-waste immobilization

International Nuclear Information System (INIS)

Crandall, J.L.

1982-01-01

Analysis of risks, environmental effects, process feasibility, and costs for disposal of immobilized high-level wastes in geologic repositories indicates that the disposal system safety has a low sensitivity to the choice of the waste disposal form

Siting the nation's first high-level nuclear waste repository: Social impacts for Utah

International Nuclear Information System (INIS)

Olshansky, S.J.

1986-01-01

The siting of a high-level nuclear waste repository in the United States has been an issue of great controversy, particulary for the states under consideration. In addition to concerns expressed about the geological stability of the proposed sites, numerous social issues have been raised by the general public--most of which have been addressed by the draft environmental impact statements. Among the social impacts raised by the Department of Engery and the general public, those receiving the greatest attention were the potential influence of the repository on local economics, tourism, and the health status of the local residents. The major issues of interest in the present study include 1) the effects of respondent knowledge of nuclear waste disposal issues on opinions of health effects and tourism, particularly as they are affected by visitation patterns, and 2) the effects of occupation and education (in particular) on knowledge of nuclear waste disposal issues and opinions on technical and non-technical aspects of siting the repository. Preliminary results indicate that only about 40 percent of the respondents have visited the national parks in southeastern Utah, but over 70 percent feel they are informed about the issues associated with siting the repository. Over 60 percent of the respondents were very concerned about the possible negative effect the repository could have on jobs, tourism, health effects, and environmental quality. Cross-tabulations indicate that the respondents self rating on knowledge of nuclear disposal issues has a statistically significant influence on responses to socioeconomic issues, yet the same self rating scale is significantly influenced by the frequency with which respondents have visited the national parks in southeastern Utah

General conceptual design study for a high-level radioactive waste repository in a granite formation

International Nuclear Information System (INIS)

1982-01-01

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

Reduction on high level radioactive waste volume and geological repository footprint with high burn-up and high thermal efficiency of HTGR

Energy Technology Data Exchange (ETDEWEB)

Fukaya, Yuji, E-mail: fukaya.yuji@jaea.go.jp; Nishihara, Tetsuo

2016-10-15

Highlights: • We evaluate the number of canisters and its footprint for HTGR. • We proposed new waste loading method for direct disposal of HTGR. • HTGR can significantly reduce HLW volume compared with LWR. - Abstract: Reduction on volume of High Level radioactive Waste (HLW) and footprint in a geological repository due to high burn-up and high thermal efficiency of High Temperature Gas-cooled Reactor (HTGR) has been investigated. A helium-cooled and graphite-moderated commercial HTGR was designed as a Gas Turbine High Temperature Reactor (GTHTR300), and that has particular features such as significantly high burn-up of approximately 120 GWd/t, high thermal efficiency around 50%, and pin-in-block type fuel. The pin-in-block type fuel was employed to reduce processed graphite volume in reprocessing. By applying the feature, effective waste loading method for direct disposal is proposed in this study. By taking into account these feature, the number of HLW canister generations and its repository footprint are evaluated by burn-up fuel composition, thermal calculation and criticality calculation in repository. As a result, it is found that the number of canisters and its repository footprint per electricity generation can be reduced by 60% compared with Light Water Reactor (LWR) representative case for direct disposal because of the higher burn-up, higher thermal efficiency, less TRU generation, and effective waste loading proposed in this study for HTGR. But, the reduced ratios change to 20% and 50% if the long term durability of LWR canister is guaranteed. For disposal with reprocessing, the number of canisters and its repository footprint per electricity generation can be reduced by 30% compared with LWR because of the 30% higher thermal efficiency of HTGR.

Overall review strategy for the Nuclear Regulatory Commission's High-Level Waste Repository Program

International Nuclear Information System (INIS)

Johnson, R.L.

1994-11-01

The Overall Review Strategy gives general guidance to the Nuclear Regulatory Commission staff for conducting it's license application and pre-license application reviews. These reviews are in support of the Commission's construction authorization decision for a geologic repository for the disposal of high-level radioactive waste. Objectives and strategies are defined that focus the staff's reviews on determining compliance with requirements of 10 CFR Part 60. These strategies define how the staff prioritizes its reviews on those key technical uncertainties considered to be most important to repository performance. Strategies also give guidance for developing, in an integrated way, the License Application Review Plan together with supporting performance assessments, analyses, and research

Waste acceptance product specifications for vitrified high-level waste forms

International Nuclear Information System (INIS)

Applewhite-Ramsey, A.; Sproull, J.F.

1993-01-01

The Nuclear Waste Policy Act of 1982 mandated that all high-level waste (HLW) be sent to a federal geologic repository for permanent disposal. DOE published the Environmental Assessment in 1982 which identified borosilicate glass as the chosen HLW form. 1 In 1985 the Department of Energy instituted a Waste Acceptance Process to assure that DWPF glass waste forms would be acceptable to such a repository. This assurance was important since production of waste forms will precede repository construction and licensing. As part of this Waste Acceptance Process, the DOE Office of Civilian Radioactive Waste Management (RW) formed the Waste Acceptance Committee (WAC). The WAC included representatives from the candidate repository sites, the waste producing sites and DOE. The WAC was responsible for developing the Waste Acceptance Preliminary Specifications (WAPS) which defined the requirements the waste forms must meet to be compatible with the candidate repository geologies

Establishing managerial requirements for low-and intermediate-level waste repository

International Nuclear Information System (INIS)

Chung, C. W.; Lee, Y. K.; Kim, H. T.; Park, W. J.; Suk, T. W.; Park, S. H.

2004-01-01

This paper reviews basic considerations for establishing managerial requirements on the domestic low-and intermediate-level radioactive waste repository and presents the corresponding draft requirements. The draft emphasizes their close linking with the related regulations, standards and safety assessment for the repository. It also proposes a desirable direction towards harmonizing together with the existing waste acceptance requirements for the repository

Peer review for high-level nuclear waste repositories: Generic technical position

International Nuclear Information System (INIS)

Altman, W.D.; Donnelly, J.P.; Kennedy, J.E.

1988-02-01

This document provides guidance on the use of the peer review process in the high-level nuclear waste repository program. The applicant must demonstrate in the license application that the applicable health, safety, and environmental regulations in 10 CFR Part 60 have been met. Confidence in the data used to support the license application is obtained through a quality assurance (AQ) program. Peer reviews may be used as part of the QA actions necessary to provide adequate confidence in the work being reviewed. Because of several unique conditions inherent to the geologic repository program, expert judgment will need to be utilized in assessing the adequacy of work. Peer reviews are a mechanism by which these judgments may be made. This document provides guidance on areas where a peer review is appropriate, the acceptability of peers, and the conduct and documentation of a peer review

Environmental issues of repository licensing: an evaluation of a hypothetical high-level radioactive waste repository

International Nuclear Information System (INIS)

Owen, J.L.; McGinnis, J.T.; Harper, C.M.; Battelle Columbus Labs., OH)

1982-01-01

This paper presents results of an environmental assessment conducted under the direction of the Office of Nuclear Waste Isolation as part of the National Waste Terminal Storage program. The study defined a range of potential environmental effects of constructing, operating, decommissioning, and long-term isolation of a nuclear waste repository. The analytical methodology used to determine potential environmental effects required definition of a hypothetical environmental setting and repository. Potentially applicable regulatory requirements were identified and were used as guidelines to evaluate permitting feasibility. The environmental effects of repository development were analyzed for the two major time periods of concern: short term (the period of construction, operation, and decommissioning) and long term (the isolation period after decommissioning). As a result of this analysis, major environmental uncertainties and issues were identified. 11 references, 5 figures

Probabilistic safety assessment for a generic deep geological repository for high-level waste and long-lived intermediate-level waste in clay

International Nuclear Information System (INIS)

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

2010-01-01

Document available in extended abstract form only. In the selection procedure for the search of a final site location for the disposal of radioactive wastes, the comparison and evaluation of different potentially suitable repository systems in different types of host rocks will be an essential and crucial step. Since internationally accepted guidelines on how to perform such quantitative comparisons between repository systems with regard to their long-term safety behaviour are still lacking, in 2007 the German Federal Office for Radiation Protection launched the project 'VerSi' (Vergleichende Sicherheitsanalysen - Comparing Safety Assessments) that aims at the development of a methodology for the comparison of long-term safety assessments. A vital part of the VerSi project is the performance of long-term safety assessments for the comparison of two repository systems. The comparison focuses on a future repository for heat-generating, i.e. high-level and long-lived intermediate-level radioactive wastes in Germany. Rock salt is considered as a potential host rock for such a repository, and one repository system in VerSi is defined similarly to the potential site located in the Gorleben salt dome. Another suitable host rock formation may be clay. A generic location within the lower Cretaceous clays in Northern Germany is therefore chosen for the comparison of safety assessments within the VerSi project. The long-term safety assessment of a repository system for heat-generating radioactive waste at the generic clay location comprises different steps, amongst others: - Identifying the relevant processes in the near-field, in the geosphere and in the biosphere which are relevant for the long-term safety behaviour. - Development of a safety concept for the repository system. - Deduction of scenarios of the long-term evolution of the repository system. - Definition of statistic weights, i. e. the likelihood of occurrence of the scenarios. - Performance of a

Socioeconomic impacts of large-scale developments: implications for high-level nuclear waste repositories

International Nuclear Information System (INIS)

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

1983-01-01

High-level nuclear waste repositories will likely be located in sparsely settled rural areas in the US. These projects will significantly affect the economic, demographic, public service, fiscal, and social (the socioeconomic) dimensions of those rural areas. The impacts and means of mitigating them thus require careful analysis. This paper examines some of the potential socioeconomic impacts likely to occur in rural areas as a result of repository siting and development, and it describes some of the characteristics of mitigation programs that are likely to be necessary, if the impacts are to be addressed. Both (1) standard impacts, those resulting from the fact that, like many other large-scale developments, repositories will involve a substantial number of new workers and residents (relative to the size of existing communities), and (2) special impacts, those resulting from the fact that repositories store radioactive materials, are examined. The discussion indicates that economic, demographic, public service, fiscal, and social impacts (standard and special) of these repositories will be substantial and problematic in many cases. Unless the impacts are effectively addressed with carefully planned and well financed mitigation efforts that insure that high-quality planning information is provided to local residents, and that local residents are involved in impact planning and management throughout the siting and development process, repository siting is unlikely to be effectively and equitably achieved. 44 references

Field instrumentation and testing needs for a high level waste repository

International Nuclear Information System (INIS)

Marti, J.; Maini, T.

1981-03-01

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

Disposal of high level and intermediate level radioactive wastes

International Nuclear Information System (INIS)

Flowers, R.H.

1991-01-01

The waste products from the nuclear industry are relatively small in volume. Apart from a few minor gaseous and liquid waste streams, containing readily dispersible elements of low radiotoxicity, all these products are processed into stable solid packages for disposal in underground repositories. Because the volumes are small, and because radioactive wastes are latecomers on the industrial scene, a whole new industry with a world-wide technological infrastructure has grown up alongside the nuclear power industry to carry out the waste processing and disposal to very high standards. Some of the technical approaches used, and the Regulatory controls which have been developed, will undoubtedly find application in the future to the management of non-radioactive toxic wastes. The repository site outlined would contain even high-level radioactive wastes and spent fuels being contained without significant radiation dose rates to the public. Water pathway dose rates are likely to be lowest for vitrified high-level wastes with spent PWR fuel and intermediate level wastes being somewhat higher. (author)

Elicitation and use of expert judgment in performance assessment for high-level radioactive waste repositories

International Nuclear Information System (INIS)

Bonano, E.J.; Hora, S.C.; Keeney, R.L.; von Winterfeldt, D.

1990-05-01

This report presents the concept of formalizing the elicitation and use of expert judgment in the performance assessment of high-level radioactive waste (HLW) repositories in deep geologic formations. The report begins with a discussion of characteristics (advantages and disadvantages) of formalizing expert judgment examples of previous uses of expert judgment in radioactive waste programs, criteria that can assist in deciding when to formalize expert judgment, and the relationship of formal use of expert judgment to data collection and modeling. The current state of the art with respect to the elicitation, use, and communication of formal expert judgment is presented. The report concludes with a discussion on potential applications of formal expert judgment in performance assessment of HLW repositories. 93 refs

Preliminary total-system analysis of a potential high-level nuclear waste repository at Yucca Mountain

International Nuclear Information System (INIS)

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

1993-01-01

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

Preliminary total-system analysis of a potential high-level nuclear waste repository at Yucca Mountain

Energy Technology Data Exchange (ETDEWEB)

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

1993-01-01

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

Sample performance assessment of a high-level radioactive waste repository: sensitivity analysis

International Nuclear Information System (INIS)

Tkaczyk, A.

2001-01-01

The Yucca Mountain Project (YMP) is the USA's first attempt at long-term storage of High-Level Radioactive Waste (HLW). In theory, the reasoning for such a repository seems sound. In practice, there are many scenarios and cases to be considered while putting such a project into effect. Since a goal of YMP is to minimize dangers associated with long-term storage of HLW, it is important to estimate the dose rate to which current and future generations will be subjected. The lifetime of the repository is simulated to indicate the radiation dose rate to the maximally exposed individual; it is assumed that if the maximally exposed individual would not be harmed by the annual dose, the remaining population will be at even smaller risk. The determination of what levels of exposure can be deemed harmless is a concern, and the results from the simulations as compared against various regulations are discussed. (author)

Sample performance assessment of a high-level radioactive waste repository: sensitivity analysis

Energy Technology Data Exchange (ETDEWEB)

Tkaczyk, A. [Iowa State Univ. of Science and Technology, Ames, IA (United States). Dept. of Mechanical Engineering

2001-07-01

The Yucca Mountain Project (YMP) is the USA's first attempt at long-term storage of High-Level Radioactive Waste (HLW). In theory, the reasoning for such a repository seems sound. In practice, there are many scenarios and cases to be considered while putting such a project into effect. Since a goal of YMP is to minimize dangers associated with long-term storage of HLW, it is important to estimate the dose rate to which current and future generations will be subjected. The lifetime of the repository is simulated to indicate the radiation dose rate to the maximally exposed individual; it is assumed that if the maximally exposed individual would not be harmed by the annual dose, the remaining population will be at even smaller risk. The determination of what levels of exposure can be deemed harmless is a concern, and the results from the simulations as compared against various regulations are discussed. (author)

An analysis of repository waste-handling operations

International Nuclear Information System (INIS)

Dennis, A.W.

1990-09-01

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

Containment barrier metals for high-level waste packages in a Tuff repository

International Nuclear Information System (INIS)

Russell, E.W.; McCright, R.D.; O'Neal, W.C.

1983-01-01

The Nevada Nuclear Waste Storage Investigations (NNWSI) Waste Package project is part of the US Department of Energy's Civilian Radioactive Waste Management (CRWM) Program. The NNWSI project is working towards the development of multibarriered packages for the disposal of spent fuel and high-level waste in tuff in the unsaturated zone at Yucca Mountain at the Nevada Test Site (NTS). The final engineered barrier system design may be composed of a waste form, canister, overpack, borehole liner, packing, and the near field host rock, or some combination thereof. Lawrence Livermore National Laboratory's (LLNL) role is to design, model, and test the waste package subsystem for the tuff repository. At the present stage of development of the nuclear waste management program at LLNL, the detailed requirements for the waste package design are not yet firmly established. In spite of these uncertainties as to the detailed package requirements, we have begun the conceptual design stage. By conceptual design, we mean design based on our best assessment of present and future regulatory requirements. We anticipate that changes will occur as the detailed requirements for waste package design are finalized. 17 references, 4 figures, 10 tables

Containment barrier metals for high-level waste packages in a Tuff repository

Energy Technology Data Exchange (ETDEWEB)

Russell, E.W.; McCright, R.D.; O`Neal, W.C.

1983-10-12

The Nevada Nuclear Waste Storage Investigations (NNWSI) Waste Package project is part of the US Department of Energy`s Civilian Radioactive Waste Management (CRWM) Program. The NNWSI project is working towards the development of multibarriered packages for the disposal of spent fuel and high-level waste in tuff in the unsaturated zone at Yucca Mountain at the Nevada Test Site (NTS). The final engineered barrier system design may be composed of a waste form, canister, overpack, borehole liner, packing, and the near field host rock, or some combination thereof. Lawrence Livermore National Laboratory`s (LLNL) role is to design, model, and test the waste package subsystem for the tuff repository. At the present stage of development of the nuclear waste management program at LLNL, the detailed requirements for the waste package design are not yet firmly established. In spite of these uncertainties as to the detailed package requirements, we have begun the conceptual design stage. By conceptual design, we mean design based on our best assessment of present and future regulatory requirements. We anticipate that changes will occur as the detailed requirements for waste package design are finalized. 17 references, 4 figures, 10 tables.

Thermal characteristics of rocks for high-level waste repository

International Nuclear Information System (INIS)

Shimooka, Kenji; Ishizaki, Kanjiro; Okamoto, Masamichi; Kumata, Masahiro; Araki, Kunio; Amano, Hiroshi

1980-12-01

Heat released by the radioactive decay of high-level waste in an underground repository causes a long term thermal disturbance in the surrounding rock mass. Several rocks constituting geological formations in Japan were gathered and specific heat, thermal conductivity, thermal expansion coefficient and compressive strength were measured. Thermal analysis and chemical analysis were also carried out. It was found that volcanic rocks, i.e. Andesite and Basalt had the most favorable thermal characteristics up to around 1000 0 C and plutonic rock, i.e. Granite had also favorable characteristics under 573 0 C, transition temperature of quartz. Other igneous rocks, i.e. Rhyolite and Propylite had a problem of decomposition at around 500 0 C. Sedimentary rocks, i.e. Zeolite, Tuff, Sandstone and Diatomite were less favorable because of their decomposition, low thermal conductivity and large thermal expansion coefficient. (author)

The preliminary design and feasibility study of the spent fuel and high level waste repository in the Czech Republic

International Nuclear Information System (INIS)

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

1996-01-01

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

Radionuclide release from high level waste forms under repository conditions in clay or granite

International Nuclear Information System (INIS)

Godon, N.; Lanza, F.

1990-01-01

The behaviour of both fully active and simulated vitrified high level waste (HLW) has been studied under conditions that are likely to occur in future repositories in clay and granite. The simulated HLW was doped with Cs, Sr, Tc and the actinides and the leaching of these elements from the glass has been measured together with their concentrations in the water of the near-field and their distribution between the various components of the repository. The diffusion coefficients of several elements in Boom clay has also been measured. The results show that the concentrations of Tc and the actinides in the near-field of a repository will be very low and that the actinides will only diffuse very slowly away from the vicinity of the glass. 24 refs., 1 figs., 7 tabs

Radioactive waste repository of high ecological safety

International Nuclear Information System (INIS)

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

2000-01-01

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

Radioactive waste isolation in salt: peer review of the Office of Nuclear Waste Isolation's report on Functional Design Criteria for a Repository for High-Level Radioactive Waste

International Nuclear Information System (INIS)

Hambley, D.F.; Russell, J.E.; Busch, J.S.; Harrison, W.; Edgar, D.E.; Tisue, M.W.

1984-08-01

This report summarizes Argonne's review of the Office of Nuclear Waste Isolation's (ONWI's) draft report entitled Functional Design Criteria for High-Level Nuclear Waste Repository in Salt, dated January 23, 1984. Recommendations are given for improving the ONWI draft report

National high-level waste systems analysis report

Energy Technology Data Exchange (ETDEWEB)

Kristofferson, K.; Oholleran, T.P.; Powell, R.H.

1995-09-01

This report documents the assessment of budgetary impacts, constraints, and repository availability on the storage and treatment of high-level waste and on both existing and pending negotiated milestones. The impacts of the availabilities of various treatment systems on schedule and throughput at four Department of Energy sites are compared to repository readiness in order to determine the prudent application of resources. The information modeled for each of these sites is integrated with a single national model. The report suggests a high-level-waste model that offers a national perspective on all high-level waste treatment and storage systems managed by the Department of Energy.

National high-level waste systems analysis report

International Nuclear Information System (INIS)

Kristofferson, K.; Oholleran, T.P.; Powell, R.H.

1995-09-01

This report documents the assessment of budgetary impacts, constraints, and repository availability on the storage and treatment of high-level waste and on both existing and pending negotiated milestones. The impacts of the availabilities of various treatment systems on schedule and throughput at four Department of Energy sites are compared to repository readiness in order to determine the prudent application of resources. The information modeled for each of these sites is integrated with a single national model. The report suggests a high-level-waste model that offers a national perspective on all high-level waste treatment and storage systems managed by the Department of Energy

The ground water chemical characteristics of Beishan area-the China's potential high level radioactive waste repository

International Nuclear Information System (INIS)

Yang Tianxiao; Guo Yonghai

2004-01-01

The ground water chemical characteristics have impact on nuclide migration in high level waste repository, so the study on the ground water chemical characteristics is an important aspect in site screening and characterization. The geochemical modeling of the reaction trend between ground water and solid phase, the water-rock interaction modeling of the formation and evolution of ground water chemistry, the modeling of the reaction between ground water and nuclear waste are all carried out in this paper to study the ground water chemical characteristics in Beishan area. The study illustrates that the ground water chemical characteristics in Beishan area is favorable to the disposal of high level nuclear waste and to prevent the nuclides migration. (author)

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

International Nuclear Information System (INIS)

Liu Jianqin; Li Honghui; Sun Qinghong; Yang Zhongtian

2012-01-01

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

Third report, development of site suitability and design performance data base for a high level nuclear waste repository

International Nuclear Information System (INIS)

1978-05-01

This report presents the results of mining and geotechnical studies provided as support for the development of a technical data base suitable for the generation of a regulatory framework governing high-level nuclear waste disposal: flow path models for basalts, salt domes, and crystalline rocks; simplistic model evaluations; loss of administrative control; repository conceptual designs; repository design considerations; and design performance criteria

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

International Nuclear Information System (INIS)

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

2009-01-01

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

Workshops for state review of site suitability criteria for high-level radioactive waste repositories: analysis and recommendations

International Nuclear Information System (INIS)

1978-02-01

The responses from various discussion groups on site suitability criteria for high-level radioactive waste repositories are presented. The consensus, principal concern, and minority opinion on each issue are given. The visual aids used in the workshop are included

Repository environmental parameters and models/methodologies relevant to assessing the performance of high-level waste packages in basalt, tuff, and salt

Energy Technology Data Exchange (ETDEWEB)

Claiborne, H.C.; Croff, A.G.; Griess, J.C.; Smith, F.J.

1987-09-01

This document provides specifications for models/methodologies that could be employed in determining postclosure repository environmental parameters relevant to the performance of high-level waste packages for the Basalt Waste Isolation Project (BWIP) at Richland, Washington, the tuff at Yucca Mountain by the Nevada Test Site, and the bedded salt in Deaf Smith County, Texas. Guidance is provided on the identify of the relevant repository environmental parameters; the models/methodologies employed to determine the parameters, and the input data base for the models/methodologies. Supporting studies included are an analysis of potential waste package failure modes leading to identification of the relevant repository environmental parameters, an evaluation of the credible range of the repository environmental parameters, and a summary of the review of existing models/methodologies currently employed in determining repository environmental parameters relevant to waste package performance. 327 refs., 26 figs., 19 tabs.

Repository environmental parameters and models/methodologies relevant to assessing the performance of high-level waste packages in basalt, tuff, and salt

International Nuclear Information System (INIS)

Claiborne, H.C.; Croff, A.G.; Griess, J.C.; Smith, F.J.

1987-09-01

This document provides specifications for models/methodologies that could be employed in determining postclosure repository environmental parameters relevant to the performance of high-level waste packages for the Basalt Waste Isolation Project (BWIP) at Richland, Washington, the tuff at Yucca Mountain by the Nevada Test Site, and the bedded salt in Deaf Smith County, Texas. Guidance is provided on the identify of the relevant repository environmental parameters; the models/methodologies employed to determine the parameters, and the input data base for the models/methodologies. Supporting studies included are an analysis of potential waste package failure modes leading to identification of the relevant repository environmental parameters, an evaluation of the credible range of the repository environmental parameters, and a summary of the review of existing models/methodologies currently employed in determining repository environmental parameters relevant to waste package performance. 327 refs., 26 figs., 19 tabs

Regional groundwater chemical characteristics of Aqishan pre-selected site for high level radioactive waste repository and its hydrogeological significance

International Nuclear Information System (INIS)

Guo Yonghai; Dong Jiannan; Liu Shufen; Zhou Zhichao

2014-01-01

Aqishan area located in Xinjiang Uygur Automonous Region is one of the main preselected site of disposal repository for high-level radioactive waste (HLW) in our country. Groundwater chemical feature is one of the most important consideration factors in the siting and site evaluation for high-level radioactive waste repository, From 2012 to 2013, the regional field hydrogeochemical investigation was carried out in study area and more than 30 groundwater samples were collected. According to the measurement data, the groundwater chemical features for different subareas are discussed in the paper. Furthermore, the location of discharge area of groundwater in Aqishan area was estimated according to the chemical features of different subareas. (authors)

High level nuclear waste repository in salt: Sealing systems status and planning report: Draft report

International Nuclear Information System (INIS)

1985-09-01

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

Engineering studies: high-level radioactive waste repositories task 3 - review of underground handling and emplacement. 1. Executive summary

Energy Technology Data Exchange (ETDEWEB)

1981-02-01

The report reviews proposals for transport, handling and emplacement of high-level radioactive waste in an underground repository with particular reference to: waste block size and configuration; self-shielded or partially-shielded block; stages of disposal; transport by road/rail to repository site; handling techniques within repository; emplacement in vertical holes or horizontal tunnels; repository access by adit, incline or shaft; conventional and radiological safety; costs; and major areas of uncertainty requiring research or development. In carrying out this programme due attention was given to work already carried out both in the U.K. and overseas and where appropriate comparisons with this work have been made to substantiate and explain the observations made in this report. The examination and use of this previous work however has been confined to those proposals which were considered capable of meeting the basic design criterion for a U.K. based repository, that the maximum temperature achieved by the host rock should not exceed 100/sup 0/C.

Acceptability of a low and intermediate level radioactive waste repository

International Nuclear Information System (INIS)

Zeleznik, N.; Polic, M.

2000-01-01

Siting of a radioactive waste repository, even for the waste of low and intermediate level (LILW) radioactivity, presents a great problem in almost every country that produces such waste. The main problem is not a technical one, but socio-psychological, namely the acceptability of this kind of repository. In general, people are opposed to any such kind of facility in their vicinity (NIMBY). In this study we try to establish the factors that influence people's behavior regarding the construction of a radioactive waste repository in their local community, with the use of Ajzen's model of planned behavior. Two different scenarios about the construction of a radioactive waste repository in their community, together with a set of questions were presented to participants from different schools. Data from the survey were analysed by multivariate methods, and a model of relevant behaviour was proposed. From the results it can be seen that different approaches to local community participation in site selection process slightly influence people's attitudes towards the LILW repository, while significant differences in answers were found in the responses which depend on participants' knowledge. Therefore the RAO Agency will further intensify preparation of the relevant communication plan and start with its implementation to support LILW repository site selection process, which will also include educational programme. (author)

Site characterization plan conceptual design report for a high-level nuclear waste repository in salt, vertical emplacement mode: Volume 1

International Nuclear Information System (INIS)

1987-12-01

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

Site characterization plan conceptual design report for a high-level nuclear waste repository in salt, vertical emplacement mode: Volume 1

Energy Technology Data Exchange (ETDEWEB)

1987-12-01

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

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

International Nuclear Information System (INIS)

1987-12-01

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

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

International Nuclear Information System (INIS)

Gaussen, JL

2006-01-01

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

Seismic considerations in sealing a potential high-level radioactive waste repository

International Nuclear Information System (INIS)

Fernandez, J.A.; Richardson, A.M.; Lin, Ming

1992-01-01

The potential repository system is intended to isolate high-level radioactive waste at Yucca Mountain. One subsystem that may contribute to achieving this objective is the sealing subsystem. This subsystem is comprised of sealing components in the shafts, ramps, underground network of drifts, and the exploratory boreholes. Sealing components can be rigid, as in the case of a shaft seal, or can be more compressible, as in the case of drift fill comprised of mined rockfill. This paper presents the preliminary seismic response of discrete sealing components in welded and nonwelded tuff. Special consideration is given to evaluating the stress in the seal, and the behavior of the interface between the seal and the rock. The seismic responses are computed using both static and dynamic analyses. Also presented is an evaluation of the maximum seismic response encountered by a drift seal with respect to the angle of incidence of the seismic wave. Mitigation strategies and seismic design considerations are proposed which can potentially enhance the overall response of the sealing component and subsequently, the performance of the overall repository system

Evaluation of commercial repository capacity for the disposal of defense high-level waste. Comments and responses for DOE/DP--0020

International Nuclear Information System (INIS)

1985-12-01

The Nuclear Waste Policy Act of 1982 (Public Law 97-425) requires that the President evaluate the use of disposal capacity at one or more repositories to be developed for permanent disposal of civilian spent nuclear fuel and high-level radioactive waste for the disposal of defense high-level radioactive waste. The Department of Energy prepared a report titled ''An Evaluation of Commercial Repository Capacity for the Disposal of Defense High-Level Waste,'' DOE/DP-0020, to provide input for the President's evaluation. The report constituted the Department's input and recommendation to be considered by the President in making his evaluation. Although not required by the Act, the Department made the July 1984 draft of the report available to the general public for review and comment in order to increase public awareness, and develop a public record on the issue of disposal of defense high-level waste. Over 400 copies of the draft report were distributed. Thirty comment letters containing over 400 comments were received from representatives of states, localities, and Indian tribes, federal agencies, organizations representing utilities, public interest groups, individual utilities, and private citizens. All letters were reviewed and considered. Where appropriate, changes were made in the final report reflecting the comments received

Hydrogeological investigation for sitting disposal repository for high level radioactive waste

International Nuclear Information System (INIS)

Guo Yonghai; Liu Shufen; Lv Chuanhe

2005-01-01

Based on the research experiences of our country and some developed countries in the world, the purpose, process and methods, as well as the function of hydrogeological investigation for sitting disposal repository for high radioactive waste are discussed. Meanwhile, the topic related to the acquisition of hydrogeological parameters is described as well, aiming at providing reference for the future study. (authors)

Future extension of the Swedish repository for low and intermediate level waste (SFR)

International Nuclear Information System (INIS)

Carlsson, Jan

2006-01-01

The existing Swedish repository for low and intermediate level waste (SFR) is licensed for disposal of short-lived waste originated from operation and maintenance of Swedish nuclear power plants. The repository is foreseen to be extended to accommodate short-lived waste from the future decommissioning of the Nuclear Power Plants. Long-lived waste from operation, maintenance and eventually decommissioning will be stored some years before disposal in a geological repository. This repository can be build either as a further extension of the SFR facility or as a separate repository. This paper discusses the strategy of a step-wise extended repository where the extensions are performed during operation of the existing parts of the repository. It describes the process for licensing new parts of the repository (and re-license of the existing parts). (author)

Public concerns and choices regarding nuclear-waste repositories

International Nuclear Information System (INIS)

Rankin, W.L.; Nealey, S.M.

1981-06-01

Survey research on nuclear power issues conducted in the late 1970's has determined that nuclear waste management is now considered to be one of the most important nuclear power issues both by the US public and by key leadership groups. The purpose of this research was to determine the importance placed on specific issues associated with high-level waste disposal. In addition, policy option choices were asked regarding the siting of both low-level and high-level nuclear waste repositories. A purposive sampling strategy was used to select six groups of respondents. Averaged across the six respondent groups, the leakage of liquid wastes from storage tanks was seen as the most important high-level waste issue. There was also general agreement that the issue regarding water entering the final repository and carrying radioactive wastes away was second in importance. Overall, the third most important issue was the corrosion of the metal containers used in the high-level waste repository. There was general agreement among groups that the fourth most important issue was reducing safety to cut costs. The fifth most important issue was radioactive waste transportation accidents. Overall, the issues ranked sixth and seventh were, respectively, workers' safety and earthquakes damaging the repository and releasing radioactivity. The eighth most important issue, overall, was regarding explosions in the repository from too much radioactivity, which is something that is not possible. There was general agreement across all six respondent groups that the two least important issues involved people accidentally digging into the site and the issue that the repository might cost too much and would therefore raise electricity bills. These data indicate that the concerns of nuclear waste technologists and other public groups do not always overlap

Hydrogeological characteristics of Beishan preselected area, Gansu province for China's high-level radioactive waste repository

International Nuclear Information System (INIS)

Guo Yonghai; Yang Tianxiao; Liu Shufen

2001-01-01

Groundwater is the major carrier for radionuclide migration in the high-level radioactive waste disposal. For this reason the hydrogeological study is one of the main contents in repository siting. According to the field investigation which has been carried out during the last few years and some data from the previous study, the author describes the general hydrogeological situation and groundwater circulation, as well as chemical characteristics of groundwater in Beishan preselected area, Gansu province. The research shows that main hydrogeological characteristics of the Beishan area is water-bearing character, low permeability and slow water movement while the major chemical feature of groundwater is high mineralization. This recognition will provide an important basis for repository siting in the site area

Waste Package and Material Testing for the Proposed Yucca Mountain High Level Waste Repository

International Nuclear Information System (INIS)

Doering, Thomas; Pasupathi, V.

2002-01-01

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

Effects of silica redistribution on performance of high-level nuclear waste repositories in saturated geologic formations

International Nuclear Information System (INIS)

Verma, A.; Pruess, K.

1985-11-01

Evaluation of the thermohydrological conditions near high-level waste packages is needed for the design of the waste canister and for overall repository design and performance assessment. Most available studies in this area have assumed that the hydrologic properties of the host rock do not change in response to the thermal, mechanical or chemical effects caused by waste emplacement. However, the ramifications of this simplifying assumption have not been substantiated. We have studied dissolution and precipitation of silica in thermally driven flow systems, including changes in formation porosity and permeability. Using numerical simulation, we compare predictions of thermohydrological conditions with and without inclusion of silica redistribution effects. Two cases were studied, namely, a canister-scale problem, a repository-wide thermal convection problem, and different pore models were employed for the permeable medium (fractures with uniform or non-uniform cross sections). We find that silica redistribution generally has insignificant effects on host rock and canister temperatures, pore pressures, or flow velocites

Geochemical modelling of bentonite porewater in high-level waste repositories

Science.gov (United States)

Wersin, Paul

2003-03-01

The description of the geochemical properties of the bentonite backfill that serves as engineered barrier for nuclear repositories is a central issue for perfomance assessment since these play a large role in determining the fate of contaminants released from the waste. In this study the porewater chemistry of bentonite was assessed with a thermodynamic modelling approach that includes ion exchange, surface complexation and mineral equilibrium reactions. The focus was to identify the geochemical reactions controlling the major ion chemistry and acid-base properties and to explore parameter uncertainties specifically at high compaction degrees. First, the adequacy of the approach was tested with two distinct surface complexation models by describing recent experimental data performed at highly varying solid/liquid ratios and ionic strengths. The results indicate adequate prediction of the entire experimental data set. Second, the modelling was extended to repository conditions, taking as an example the current Swiss concept for high-level waste where the compacted bentonite backfill is surrounded by argillaceous rock. The main reactions controlling major ion chemistry were found to be calcite equilibrium and concurrent Na-Ca exchange reactions and de-protonation of functional surface groups. Third, a sensitivity analysis of the main model parameters was performed. The results thereof indicate a remarkable robustness of the model with regard to parameter uncertainties. The bentonite system is characterised by a large acid-base buffering capacity which leads to stable pH-conditions. The uncertainty in pH was found to be mainly induced by the pCO 2 of the surrounding host rock. The results of a simple diffusion-reaction model indicate only minor changes of porewater composition with time, which is primarily due to the geochemical similarities of the bentonite and the argillaceous host rock. Overall, the results show the usefulness of simple thermodynamic models to

Modelling magma-drift interaction at the proposed high-level radioactive waste repository at Yucca Mountain, Nevada, USA

NARCIS (Netherlands)

Woods, Andrew W.; Sparks, Steve; Bokhove, Onno; Lejeune, Anne-Marie; Connor, Charles B.; Hill, Britain E.

2002-01-01

We examine the possible ascent of alkali basalt magma containing 2 wt percent water through a dike and into a horizontal subsurface drift as part of a risk assessment for the proposed high-level radioactive waste repository beneath Yucca Mountain, Nevada, USA. On intersection of the dike with the

Low and intermediate level waste repositories: public involvement aspects

International Nuclear Information System (INIS)

Ferreira, Vinicius V.M.; Mourao, Rogerio P.; Fleming, Peter M.; Soares, Wellington A.; Braga, Leticia T.P.; Santos, Rosana A.M.

2009-01-01

The nuclear energy acceptance creates several problems, and one of the most important is the disposal of the radioactive waste. International experiences show that not only environmental, radiological and technical questions have to be analyzed, but the public opinion about the project must be considered. The objective of this article is to summarize some public involvement aspects associated with low and intermediate level waste repositories. Experiences from USA, Canada, South Africa, Ukraine and other countries are studied and show the importance of the population in the site selection process for a repository. (author)

Use of geostatistics in high level radioactive waste repository site characterization

Energy Technology Data Exchange (ETDEWEB)

Doctor, P G [Pacific Northwest Laboratory, Richland, WA (USA)

1980-09-01

In evaluating and characterizing sites that are candidates for use as repositories for high-level radioactive waste, there is an increasing need to estimate the uncertainty in hydrogeologic data and in the quantities calculated from them. This paper discusses the use of geostatistical techniques to estimate hydrogeologic surfaces, such as the top of a basalt formation, and to provide a measure of the uncertainty in that estimate. Maps of the uncertainty estimate, called the kriging error, can be used to evaluate where new data should be taken to affect the greatest reduction in uncertainty in the estimated surface. The methods are illustrated on a set of site-characterization data; the top-of-basalt elevations at the Hanford Site near Richland, Washington.

Sandia studies of high-level waste canisters and overpacks applicable for a salt repository

International Nuclear Information System (INIS)

Molecke, M.A.; Schaefer, D.W.; Glass, R.S.; Ruppen, J.A.

1982-01-01

An experimental program to develop candidate materials for use as high-level waste (HLW) overpacks or canisters in a salt repository has been in progress at Sandia National Laboratories since 1976. The main objective of this program is to provide a waste package barrier having a long lifetime in the chemical and physical environment of a repository. This paper summarizes the recent corrosion and metallurgical study results for the prime overpack material, TiCode-12, in the areas of uniform corrosion (extremely low rate and extent); local attack, e.g., pits and crevices (none were found); stress corrosion cracking susceptibility (no significant changes in macroscopic tensile properties were detected); hydrogen sorption-embrittlement effects; effects of gamma irradiation in solution; and sensitization effects (testing is still in process in the last three areas). Previous candidate screening analyses on other alloys and recent work on alternate overpack alloys are reviewed. All phases of these interrelated laboratory, hot-cell, and field experimental studies are described. 16 references, 8 figures, 4 tables

Seismic considerations in sealing a potential high-level radioactive waste repository

International Nuclear Information System (INIS)

Fernandez, J.A.; Richardson, A.M.; Lin, Ming

1993-01-01

The potential repository system is intended to isolate high-level radioactive waste at Yucca Mountain according the performance objective--10 CFR 60.112. One subsystem that may contribute to achieving this objective is the sealing subsystem. This subsystem is comprised of sealing components in the shafts, ramps, underground network of drifts, and the exploratory boreholes. Sealing components can be rigid, as in the case of a shaft seal, or can be more compressible, as in the case of drift fill comprised of mined rockfill. This paper presents the preliminary seismic response of discrete sealing components in welded and nonwelded tuff. Special consideration is given to evaluating the stress in the seal, and the behavior of the interface between the seal and the rock. The seismic responses are computed using both static and dynamic analyses. Also presented is an evaluation of the maximum seismic response encountered by a drift seal with respect to the angle of incidence of the seismic wave. Mitigation strategies and seismic design considerations are proposed which can potentially enhance the overall response of the sealing component and subsequently, the performance of the overall repository system

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

International Nuclear Information System (INIS)

1990-06-01

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

United States regulations for institutional controls at high-level waste repositories

International Nuclear Information System (INIS)

Piccone, Josephine

2015-01-01

The United States regulations for disposal of spent nuclear fuel and high-level radioactive waste are found at Title 10 of the Code of Federal Regulations (10 CFR) Parts 60 and 63, which cover deep geologic disposal at a generic site and at Yucca Mountain, Nevada, respectively. As an independent regulator, the US Nuclear Regulatory Commission (NRC) is responsible for licensing and oversight of a high-level waste repository in the United States. The licensing approach for disposal has discreet decisions, made by the NRC, that include approval of construction authorisation, approval to receive and possess high-level radioactive waste, and approval for permanent closure. For construction authorisation approval, the applicant must provide a description of the programme to be used to maintain the records. The NRC will have an active oversight role during the construction and operation period, which can be on the order of 100 years for the facility before permanent closure. The oversight activities are part of the active institutional controls, and serve as a means of conveying knowledge for that initial period, given that this will likely involve multiple generations of workers for both the implementer and the regulator. Additionally, the NRC provides requirements for the physical protection of stored spent nuclear fuel and high-level radioactive waste at 10 CFR Chap. 73.51. For permanent closure approval, the applicant must provide a detailed description of the measures to be employed-such as land use controls, construction of monuments, and preservation of records. The NRC's regulatory role in any licensing action is to apply the applicable regulations and guidance, and to review applications for proposed actions to determine if compliance with regulations has been achieved. The burden of proof is on the applicant or licensee to show that the proposed action is safe, to demonstrate that regulations are met, and to ensure continued compliance with the regulations

Stress corrosion cracking tests on high-level-waste container materials in simulated tuff repository environments

International Nuclear Information System (INIS)

Abraham, T.; Jain, H.; Soo, P.

1986-06-01

Types 304L, 316L, and 321 austenitic stainless steel and Incoloy 825 are being considered as candidate container materials for emplacing high-level waste in a tuff repository. The stress corrosion cracking susceptibility of these materials under simulated tuff repository conditions was evaluated by using the notched C-ring method. The tests were conducted in boiling synthetic groundwater as well as in the steam/air phase above the boiling solutions. All specimens were in contact with crushed Topopah Spring tuff. The investigation showed that microcracks are frequently observed after testing as a result of stress corrosion cracking or intergranular attack. Results showing changes in water chemistry during test are also presented

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

International Nuclear Information System (INIS)

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

1983-01-01

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

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

International Nuclear Information System (INIS)

Bretheau, F.; Lewi, J.

1990-06-01

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

Prediction of temperature increases in a salt repository expected from the storage of spent fuel or high-level waste

International Nuclear Information System (INIS)

Llewellyn, G.H.

1978-04-01

Comparisons in temperature increases incurred from hypothetical storage of 133 MW of 10-year-old spent fuel (SF) or high-level waste (HLW) in underground salt formations have been made using the HEATING5 computer code. The comparisons are based on far-field homogenized models that cover areas of 65 and 25 sq miles for SF and HLW, respectively, and near-field unit-cell models covering respective areas of 610 ft 2 and 400 ft 2 . Preliminary comparisons based on heat loads of 150 kW/acre and 3.5 kW/canister indicated near-field temperature increases about 20% higher for the storage of the spent fuel than for the high-level waste. In these comparisons, it was also found that the thermal energy deposited in the salt after 500 years is about twice the energy deposited by the high-level waste. The thermal load in a repository containing 10-year-old spent fuel was thus limited to 60 kW/acre to obtain comparable far-field thermal effects as obtained in a repository containing 10-year-old high-level waste loaded at 150 kW/acre. Detailed far-field and unit-cell comparisons of transient temperature increases have been made based on these loadings. Unit-cell comparisons were made between a canister containing high-level waste with an initial heat production rate of 2.1 kW and a canister containing a PWR spent fuel assembly producing 0.55 kW. Using a three-dimensional unit-cell model, a maximum salt temperature increase of 260 0 F was calculated for the high-level waste prior to back-filling (5 years after burial), whereas a maximum temperature increase of 110 0 F was calculated for the spent fuel prior to backfilling (25 years after burial). Comparisons were also made between various configurational models for the high-level waste showing the applicability of each model

Environmental program planning for the proposed high-level nuclear waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

1987-08-01

This report was prepared to illustrate the policy and actions that the State of Nevada believe are required to assure that the quality of the environment is adequately considered during the course of the DOE work at the proposed high-level nuclear waste repository at Yucca Mountain. The report describes the DOE environmental program and the studies planned by NWPO to reflect the State's position toward environmental protection. 41 refs., 2 figs., 11 tabs

Seismotectonic investigations for Yucca Mountain high-level waste repository: Rationale for defining scope

International Nuclear Information System (INIS)

Gupta, D.C.; Blackford, M.E.

1990-01-01

The geologic, seismic, and engineering characteristics of the Yucca Mountain site and its environs need to be investigated in sufficient scope and detail to provide reasonable assurance that they are sufficiently well understood to permit an adequate evaluation of the proposed site for the development of a high-level waste repository. The paper examines the extent of seismotectonic investigations needed for proper evaluation of the geologic setting. At the Yucca Mountain site, a thorough understanding of tectonic phenomena such as seismicity and faulting is critical to the identification of potentially disqualifying conditions. Study of the tectonic movement, stress, or co-tectonic effects that could affect the performance of the waste-handling facilities, waste package, underground openings, shaft and borehole seals, and long-term alteration of geohydrology would be necessary. In addition, the uncertainties involved in evaluating the effect of seismotectonics on the radionuclide transport mechanism need to be thoroughly investigated. 8 refs., 1 fig

Technical position on items and activities in the high-level waste geologic repository program subject to quality assurance requirements

International Nuclear Information System (INIS)

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

1988-04-01

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

Is it possible to demonstrate compliance with the regulations for high-level-waste repositories?

International Nuclear Information System (INIS)

Bingham, F.W.

1992-01-01

The regulations that currently govern repositories for spent fuel and high-level waste require demonstrations that are sometimes described as impossible to make. To make them will require an understanding of the current and the future phenomena at repository sites; it will also require credible estimates of the probabilities that the phenomena will occur in the distant future. Experts in many fields emdash earth sciences, statistics, numerical modeling, and the law emdash have questioned whether any amount of data collection can allow modelers to meet these requirements with enough confidence to satisfy the regulators. In recent years some performance assessments have begun to shed light on this question because they use results of actual site investigations. Although these studies do not settle the question definitively, a review of a recent total-system assessment suggests that compliance may be possible to demonstrate. The review also suggests, however, that the demonstration can be only at the ''reasonable'' levels of assurance mentioned, but not defined, in the regulations

Seismic design ampersand analysis considerations for high level nuclear waste repositories

International Nuclear Information System (INIS)

Hossain, Q.A.

1993-01-01

A high level nuclear waste repository, like the one at Nevada's Yucca Mountain that is being investigated for site suitability, will have some unique seismic design and analysis considerations. These are discussed, and a design philosophy that can rationally account for the unique performance objectives of such facilities is presented. A case is made for the use of DOE's performance goal-based seismic design and evaluation methodology that is based on a hybrid open-quotes deterministicclose quotes and open-quotes probabilisticclose quotes concept. How and to what extent this methodology should be modified to adopt it for a potential site like Yucca Mountain is also outlined. Finally, the issue of designing for seismic fault rupture is discussed briefly, and the desirability of using the proposed seismic design philosophy in fault rupture evaluation is described

Seismic design and analysis considerations for high level nuclear waste repositories

International Nuclear Information System (INIS)

Hossain, Q.A.

1993-01-01

A high level nuclear waste repository, like the one at Nevada's Yucca Mountain that is being investigated for site suitability, will have some unique seismic design and analysis considerations. These are discussed, and a design philosophy that can rationally account for the unique performance objectives of such facilities is presented. A case is made for the use of DOE's performance goal-based seismic design and evaluation methodology that is based on a hybrid ''deterministic'' and ''probabilistic'' concept. How and to what extent this methodology should be modified to adopt it for a potential site like Yucca Mountain is also outlined. Finally, the issue of designing for seismic fault rupture is discussed briefly, and the desirability of using the proposed seismic design philosophy in fault rupture evaluation is described

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

International Nuclear Information System (INIS)

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

1987-01-01

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

High Level Radioactive Waste Management

International Nuclear Information System (INIS)

1991-01-01

The proceedings of the second annual international conference on High Level Radioactive Waste Management, held on April 28--May 3, 1991, Las Vegas, Nevada, provides information on the current technical issue related to international high level radioactive waste management activities and how they relate to society as a whole. Besides discussing such technical topics as the best form of the waste, the integrity of storage containers, design and construction of a repository, the broader social aspects of these issues are explored in papers on such subjects as conformance to regulations, transportation safety, and public education. By providing this wider perspective of high level radioactive waste management, it becomes apparent that the various disciplines involved in this field are interrelated and that they should work to integrate their waste management activities. Individual records are processed separately for the data bases

Public reactions to nuclear waste: Citizens' views of repository siting

International Nuclear Information System (INIS)

Rosa, E.A.

1993-01-01

This book presents revised and updated papers from a panel of social scientists, at the 1989 AAAS meetings, that examined the public's reactions to nuclear waste disposal and the repository siting process. The papers report the results of original empirical research on citizens' views of nuclear waste repository siting. Topics covered include the following: content analysis of public testimony; sources of public concern about nuclear waste disposal in Texas agricultural communities; local attitudes toward high-level waste repository at Hanford; perceived risk and attitudes toward nuclear wastes; attitudes of Nevada urban residents toward a nuclear waste repository; attitudes of rural community residents toward a nuclear waste respository. An introductory chapter provides background and context, and a concluding chapter summarizes the implications of the reports. Two additional chapters cover important features of high-level waste disposal: long term trends in public attitudes toward nuclear energy and nuclear waste policy and assessment of the effects on the Los Vegas convention business if a high-level nuclear waste depository were sited in Nevada

A geotechnical evaluation of potentially acceptable sites for a high-level nuclear waste repository near the Red Lake Indian Reservation

International Nuclear Information System (INIS)

1986-01-01

The scope and work which served as the basis for this report included the following major activities; (1) A review and summary of the screening methodologies utilized by DOE for the selection of proposed nuclear waste repository sites, including a description of the inherent weakness in those methodologies. (2) A description of the geologic and hydrologic features of the rock bodies selected by DOE and an identification of those features which could result in hazardous conditions as a result of the location of a high-level nuclear waste repository. (3) An assessment of potential environmental impacts of the repository and discussion of endanged species in the proposed repository project areas. This report is organized in three major sections in relationship to the scope of work. A list of references is also included at the end of this report. 37 refs., 2 figs

Selection and Basic Properties of the Buffer Material for High-Level Radioactive Waste Repository in China

Institute of Scientific and Technical Information of China (English)

WEN Zhijian

2008-01-01

Radioactive wastes arising from a wide range of human activities are in many different physical and chemical forms, contaminated with varying radioactivity. Their common features are the potential hazard associated with their radioactivity and the need to manage them in such a way as to protect the human environment. The geological disposal is regarded as the most reasonable and effective way to safely disposing high-level radioactive wastes in the world. The conceptual model of geological disposal in China is based on a multi-barrier system that combines an isolating geological environment with an engineered barrier system. The buffer is one of the main engineered barriers for HLW repository. It is expected to maintain its low water permeability, self-sealing property, radio nuclides adsorption and retardation properties, thermal conductivity, chemical buffering property,canister supporting property, and stress buffering property over a long period of time. Bentonite is selected as the main content of buffer material that can satisfy the above requirements. The Gaomiaozi deposit is selected as the candidate supplier for China's buffer material of high level radioactive waste repository. This paper presents the geological features of the GMZ deposit and basic properties of the GMZ Na-bentonite. It is a super-large deposit with a high content of montmorillonite (about 75%), and GMZ-1, which is Na-bentonite produced from GMZ deposit is selected as the reference material for China's buffer material study.

Aspects of potential magmatic disruption of a high-level radioactive waste repository in southern Nevada

International Nuclear Information System (INIS)

Crowe, B.; Self, S.; Vaniman, D.; Amos, R.; Perry, F.

1983-01-01

Volcanic hazard studies, combining standard techniques of hazard appraisal and risk assessment are being undertaken with respect to storage of high-level, radioactive waste in southern Nevada. Consequence studies, the emphasis of this work, are evaluated by tracing the steps of ascent of basaltic magma including intersection and disruption of a repository followed by surface eruption. Theoretical considerations suggest basalt magma ascends rapidly from mantle depth (10's of cm/sec in the bubble-free regime) but may be trapped temporarily and fractionate at the mantle/crust interface. Basalt centers are fed from narrow linear dikes. Local sheet-like intrusions formed at depths of 200 to 300 m probably due to a combination of extensional faulting during emplacement and trapping within low-density tuff country rock, aided in part by a low magma-volatile content. Incorporation of radioactive waste in basalt magma is controlled by the dimensions of basalt dikes at repository depths and the depth of magma fragmentation. Dispersal pathways of waste should follow the pyroclastic component of a Strombolian eruption. The maximum volume of waste deposited with basaltic tephra can be traced approximately by assuming waste material is dispersed in the same patterns as country rock lithic fragments. Based on a basalt magma cycle that is similar to typical Strombolian centers, 180 m 3 of a repository inventory will be deposited in a scoria cone (of which approx. 1 m 3 will be exposed to the surface in a 10,000-year period), 320 to 900 m 3 will be deposited in a scoria-fall sheet (up to 12-km dispersal), and 21 m 3 will be dispersed regionally with a fine-grained particle component. 62 references, 8 figures, 2 tables

Fabrication and closure development of corrosion resistant containers for Nevada's Yucca Mountain high-level nuclear waste repository

International Nuclear Information System (INIS)

Russell, E.W.; Nelson, T.A.; Domian, H.A.; LaCount, D.F.; Robitz, E.S.; Stein, K.O.

1989-11-01

US Congress and the President have determined that the Yucca Mountain site in Nevada is to be characterized to determine its suitability for construction of the first US high-level nuclear waste repository. Work in connection with this site is carried out within the Yucca Mountain Project (YMP). Lawrence Livermore National Laboratory (LLNL) has the responsibility for designing, developing, and projecting the performance of the waste package for the permanent storage of high-level nuclear waste. Babcock ampersand Wilcox (B ampersand W) is involved with the YMP as a subcontractor to LLNL. B ampersand W's role is to recommend and demonstrate a method for fabricating the metallic waste container and a method for performing the final closure of the container after it has been filled with waste. Various fabrication and closure methods are under consideration for the production of containers. This paper presents progress to date in identifying and evaluating the candidate manufacturing processes. 2 refs., 2 figs., 4 tabs

Initial demonstration of the NRC`s capability to conduct a performance assessment for a High-Level Waste Repository

Energy Technology Data Exchange (ETDEWEB)

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

1992-05-01

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

Self-sealing of rock fractures. A possibility around the repositories of high-level radioactive wastes

International Nuclear Information System (INIS)

Chigira, Masahiro; Nakata, Eiji

1995-01-01

To the goal of the safe geological disposal of high-level radioactive wastes (HLW), we must provide long-term confidence for the isolation of HLW in various ways. In particular, groundwater flow, the most likely transport media of radioactive nuclides from HLW, must be restricted around a repository for long time. For that purpose, grouting techniques using cement, bentonite, or other materials have been studied in many countries. In this paper we report the results of a series of experiments on silica precipitation behavior in a flow path with negative temperature gradients in granite and also describe a natural example of hydrothermal alteration of diatomite intruded by andesite. Based on these, we will discuss the possibility of self-sealing around HLW repository. (J.P.N.)

Numerical aspects of the modelling of the local effects of a high level waste repository

International Nuclear Information System (INIS)

Ferreri, J.C.; Ventura, M.A.

1985-01-01

The numerical approximations adapted for the development of the computational models for the prediction of the effects of the emplacement of a high level waste repository are reviewed. The problems considered include: the thermal history of the rocky mass constituting the burial media, the flow of underground water and the associated migration of radionuclides in the same media. Results associated with verification of the implemented codes are presented. Their limitations and advantages are discussed. (Author) [es

Summary report of first and foreign high-level waste repository concepts

International Nuclear Information System (INIS)

Hanke, P.M.

1987-01-01

Reference repository concepts designs adopted by domestic and foreign waste disposal programs are reviewed. Designs fall into three basic categories: deep borehole from the surface; disposal in boreholes drilled from underground excavations; and disposal in horizontal tunnels or drifts. The repository concepts developed in Sweden, Switzerland, Finland, Canada, France, Japan, United Kingdom, Belgium, Italy, Holland, Denmark, West Germany and the United States are described. 140 refs., 315 figs., 19 tabs

Project Guarantee 1985. Final repository for high-level radioactive wastes: Safety report

International Nuclear Information System (INIS)

Anon.

1985-01-01

Disposal of radioactive was involves preventing releases to the biosphere for a long period of time and subsequently limiting the magnitude of releases by means of a series of safety barriers: the waste solidification matrix (borosilicate glass), massive steel canisters in highly compacted bentonite, sealing of void spacer and access routes on repository closure. The geological barriers are formed by the crystalline bed-rock and the overlying sedimentary layers. In order to perform a safety assessment the behaviour of these technical barriers and of the host rock must be understood and this understanding must be translated into quantitative models which allow calculation of repository performance. For the particular case of a Swiss repository, the main criterion is the individual dose limit of 10 mrem/year, which is given in the safety guidelines of the Swiss authorities. The procedure for the safety analysis involves examination of all scenarios which could give rise to radionuclide release from the repository. Qualitative considerations of both the magnitude of their consequences and their likelihood are used in order to identify a restricted number of scenarios for quantitative analysis

Effects of perched water on thermally driven moisture flow at the proposed Yucca Mountain repository for high-level waste

International Nuclear Information System (INIS)

Ofoegbu, G.I.; Bagtzoglou, A.C.; Green, R.T.; Muller, M.A.

1999-01-01

Numerical modeling was conducted to identify potential perched-water sites and examine the effects of perched water on thermally driven moisture flow at the proposed Yucca Mountain repository for high-level nuclear waste. It is demonstrated that perched-water zones may occur at two horizons on the up-dip side of faults such as the Ghost Dance Fault (GDF): in nonwelded volcanic strata [such as the Paintbrush Tuff nonwelded (PTn) stratigraphic unit], where juxtaposition of welded strata against nonwelded may constitute a barrier to lateral flow within the nonwelded strata; and in fractured horizons of underlying welded units [such as the Topopah Spring welded (TSw) unit] because of focused infiltration fed by overlying perched zones. The potential perched zones (PPZs) may contain perched water (which would flow freely into a well or opening) if infiltration rates are high enough. At lower infiltration rates, the PPZs contain only capillary-held water at relatively high saturations. Areas of the proposed repository that lie below PPZs are likely to experience relatively high percolation flux even if the PPZ contains only capillary-held water at high saturation. As a result, PPZs that contain only capillary-held water may be as important to repository performance as those that contain perched water. Thermal loading from emplaced waste in the repository is not likely to have an effect on PPZs located on adequate distance above the repository (such as in the PTn). As a result, such PPZs may be considered as permanent features of the environment. On the other hand, PPZs close to the repository depth (such as those that may occur in the TSw rock unit) would experience an initial period of spatial growth and increased saturation following waste emplacement. Thereafter, drying would begin at the repository horizon with perched-zone growth simultaneously above and below the repository. As a result, after the initial period of expansion, PPZs close to the repository horizon

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

International Nuclear Information System (INIS)

1983-06-01

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

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

International Nuclear Information System (INIS)

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

1995-01-01

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

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

Science.gov (United States)

Stuckless, John S.; Levich, Robert A.

2012-01-01

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

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

Science.gov (United States)

Stuckless, John S.; Levich, Robert A.

2012-01-01

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

Project Guarantee 1985. Repository for low- and intermediate-level radioactive waste: construction and operation

International Nuclear Information System (INIS)

Anon.

1985-01-01

A constructional engineering project study aimed at clarification of the feasibility of a repository for low- and intermediate-level radioactive waste (type B repository) has been carried out; the study is based on a model data-set derived from the geological, rock mechanical and topographical characterictics of one of Nagra's planned exploration areas. Final storage is effected in subterranean rock caverns accessed by horizontal tunnel. The reception area also is sited below the surface. Storage is conceived in such a way that, after closure of the repository, maintenance and supervision can be dispensed with and a guarantee of high long-term safety can nevertheless be provided. The envisaged repository consists of an entry tunnel for road vehicles and a reception area with a series of caverns for receiving waste, for additional technical facilities and for the production of the concrete back-fill material. The connecting tunnel is serviced by a tunnel railway and the actual repository area consists of several storage caverns. The repository is intended to accomodate a total of 200'000 m3 of solidified low- and intermediate-level waste. Valanginian marl is assumed as the host rock, although it would also be basically possible to house the proposed installations in other host rocks. The excavated material will total around 1'000'000 m3. The construction time for the whole installation is estimated as about 7 years and a working team of around 30 people will be required for the estimated 60-year operational duration. The project described in the present report justifies the conclusion that construction of a repository for low-and intermediate-level radioactive waste is feasible with present-day technology. This conclusion takes into consideration quantitative and operational constraints as well as geological and hydrogeological data relevant to constructional engineering. The latter are derived from a model data-set based on a specific locality

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

International Nuclear Information System (INIS)

1983-10-01

The conceptual waste package interim product specifications and data requirements presented are applicable to the reference glass composition described in PNL-3838 and carbon steel canister described in ONWI-438. They provide preliminary numerical values for the commercial high-level waste form parameters and properties identified in the waste form performance specification for geologic isolation in salt repositories. Subject areas treated include containment and isolation, operational period safety, criticality control, waste form/production canister identification, and waste package performance testing requirements. This document was generated for use in the development of conceptual waste package designs in salt. It will be revised as additional data, analyses and regulatory requirements become available. 13 references, 1 figure

Spent fuel and high level waste: Chemical durability and performance under simulated repository conditions. Results of a coordinated research project 1998-2004

International Nuclear Information System (INIS)

2007-10-01

This publication contains the results of an IAEA Coordinated Research Project (CRP). It provides a basis for understanding the potential interactions of waste form and repository environment, which is necessary for the development of the design and safety case for deep disposal. Types of high level waste matrices investigated include spent fuel, glasses and ceramics. Of particular interest are the experimental results pertaining to ceramic forms such as SYNROC. This publication also outlines important areas for future work, namely, standardized, collaborative experimental protocols for package-release studies, structured development and calibration of predictive models linking the performance of packaged waste and the repository environment, and studies of the long term behaviour of the wastes, including active waste samples

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

Science.gov (United States)

Pang, Bo; Becker, Frank

2017-04-28

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

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

International Nuclear Information System (INIS)

1991-10-01

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

Selection criteria for container materials at the proposed Yucca Mountain high level nuclear waste repository

International Nuclear Information System (INIS)

Halsey, W.G.

1989-11-01

A geological repository has been proposed for the permanent disposal of the nation's high level nuclear waste at Yucca Mountain in the Nevada desert. The containers for this waste must remain intact for the unprecedented service lifetime of 1000 years. A combination of engineering, regulatory, and licensing requirements complicate the container material selection. In parallel to gathering information regarding the Yucca Mountain service environment and material performance data, a set of selection criteria have been established which compare candidate materials to the performance requirements, and allow a quantitative comparison of candidates. These criteria assign relative weighting to varied topic areas such as mechanical properties, corrosion resistance, fabricability, and cost. Considering the long service life of the waste containers, it is not surprising that the corrosion behavior of the material is a dominant factor. 7 refs

Materials Degradation Issues in the U.S. High-Level Nuclear Waste Repository

Energy Technology Data Exchange (ETDEWEB)

K.G. Mon; F. Hua

2005-04-12

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

Materials Degradation Issues in the U.S. High-Level Nuclear Waste Repository

International Nuclear Information System (INIS)

Mon, K.G.; Hua, F.

2005-01-01

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

Repository for high level radioactive wastes in Brazil: the importance of geochemical (Micro thermometric) studies and fluid migration in potential host rocks

International Nuclear Information System (INIS)

Rios, Francisco Javier; Fuzikawa, Kazuo; Alves, James Vieira; Neves, Jose Marques Correia

2003-01-01

A detailed fluid inclusion study of host rocks, is of fundamental importance in the selection of geologically suitable areas for high level nuclear waste repository constructions (HLRW). The LIFM-CDTN is enabled to develop studies that confirm: the presence or not, of corrosive fluid in minerals from host rocks of the repository and the possible presence of micro fractures (and fluid leakage) when these rocks are submitted to high temperatures. These fluid geochemistry studies, with permeability determinations by means of pressurized air injection must be carried out in rocks hosting nuclear waste. Micro fracture determination is of vital importance since many naturally corrosive solutions, present in the mineral rocks, could flow out through these plans affecting the walls of the repository. (author)

Thermal modeling for a potential high-level nuclear waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Pruess, K.; Tsang, Y.

1994-03-01

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

Evaluation of conditioned high-level waste forms

International Nuclear Information System (INIS)

Mendel, J.E.; Turcotte, R.P.; Chikalla, T.D.; Hench, L.L.

1983-01-01

The evaluation of conditioned high-level waste forms requires an understanding of radiation and thermal effects, mechanical properties, volatility, and chemical durability. As a result of nuclear waste research and development programs in many countries, a good understanding of these factors is available for borosilicate glass containing high-level waste. The IAEA through its coordinated research program has contributed to this understanding. Methods used in the evaluation of conditioned high-level waste forms are reviewed. In the US, this evaluation has been facilitated by the definition of standard test methods by the Materials Characterization Center (MCC), which was established by the Department of Energy (DOE) in 1979. The DOE has also established a 20-member Materials Review Board to peer-review the activities of the MCC. In addition to comparing waste forms, testing must be done to evaluate the behavior of waste forms in geologic repositories. Such testing is complex; accelerated tests are required to predict expected behavior for thousands of years. The tests must be multicomponent tests to ensure that all potential interactions between waste form, canister/overpack and corrosion products, backfill, intruding ground water and the repository rock, are accounted for. An overview of the status of such multicomponent testing is presented

Ramifications of defining high-level waste

International Nuclear Information System (INIS)

Wood, D.E.; Campbell, M.H.; Shupe, M.W.

1987-01-01

The Nuclear Regulatory Commission (NRC) is considering rule making to provide a concentration-based definition of high-level waste (HLW) under authority derived from the Nuclear Waste Policy Act (NWPA) of 1982 and the Low Level Waste Policy Amendments Act of 1985. The Department of Energy (DOE), which has the responsibility to dispose of certain kinds of commercial waste, is supporting development of a risk-based classification system by the Oak Ridge National Laboratory to assist in developing and implementing the NRC rule. The system is two dimensional, with the axes based on the phrases highly radioactive and requires permanent isolation in the definition of HLW in the NWPA. Defining HLW will reduce the ambiguity in the present source-based definition by providing concentration limits to establish which materials are to be called HLW. The system allows the possibility of greater-confinement disposal for some wastes which do not require the degree of isolation provided by a repository. The definition of HLW will provide a firm basis for waste processing options which involve partitioning of waste into a high-activity stream for repository disposal, and a low-activity stream for disposal elsewhere. Several possible classification systems have been derived and the characteristics of each are discussed. The Defense High Level Waste Technology Lead Office at DOE - Richland Operations Office, supported by Rockwell Hanford Operations, has coordinated reviews of the ORNL work by a technical peer review group and other DOE offices. The reviews produced several recommendations and identified several issues to be addressed in the NRC rule making. 10 references, 3 figures

Aspects of possible magmatic disruption of a high-level radioactive waste repository in southern Nevada

International Nuclear Information System (INIS)

Crowe, B.; Amos, R.; Perry, F.; Self, S.; Vaniman, D.

1982-10-01

The Nevada Test Site (NTS) region is located within the central section of a north-northeast-trending basaltic volcanic belt of late Cenozoic age, a part of the Quaternary volcanic province of the Great Basin. Future volcanism within the belt represents a potential hazard to storage of high-level radioactive waste within a buried repository located in the southwestern NTS. The hazards of future volcanism in the region are being characterized through a combination of volcanic hazards studies, probability determinations, and consequence analyses. Basaltic activity within the NTS regions is divided into two age groups consisting of relatively large-volume silicic cycle basalts (8 to 10 Myr) and rift basalts (< 8 to 0.3 Myr). This paper describes the processes of basaltic magmatism ranging from derivation of basalt melts at depth, through ascent through the upper mantle and crust, to surface eruption. Each stage in the evolution and dispersal of basaltic magma is described, and the disruption and potential dispersal of stored radioactive waste is evaluated. These data document areas of knowns and unknowns in the processes of basaltic volcanisms and provide background data necessary to assist calculations of radiation release levels due to disruption of a repository. 9 figures, 11 tables

Uncertainty and sensitivity analysis in performance assessment for the proposed high-level radioactive waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Helton, Jon C.; Hansen, Clifford W.; Sallaberry, Cédric J.

2012-01-01

Extensive work has been carried out by the U.S. Department of Energy (DOE) in the development of a proposed geologic repository at Yucca Mountain (YM), Nevada, for the disposal of high-level radioactive waste. As part of this development, a detailed performance assessment (PA) for the YM repository was completed in 2008 and supported a license application by the DOE to the U.S. Nuclear Regulatory Commission (NRC) for the construction of the YM repository. The following aspects of the 2008 YM PA are described in this presentation: (i) conceptual structure and computational organization, (ii) uncertainty and sensitivity analysis techniques in use, (iii) uncertainty and sensitivity analysis for physical processes, and (iv) uncertainty and sensitivity analysis for expected dose to the reasonably maximally exposed individual (RMEI) specified the NRC’s regulations for the YM repository. - Highlights: ► An overview of performance assessment for the proposed Yucca Mountain radioactive waste repository is presented. ► Conceptual structure and computational organization are described. ► Uncertainty and sensitivity analysis techniques are described. ► Uncertainty and sensitivity analysis results for physical processes are presented. ► Uncertainty and sensitivity analysis results for expected dose are presented.

Waste package designs for disposal of high-level waste in salt formations

International Nuclear Information System (INIS)

Basham, S.J. Jr.; Carr, J.A.

1984-01-01

In the United States of America the selected method for disposal of radioactive waste is mined repositories located in suitable geohydrological settings. Currently four types of host rocks are under consideration: tuff, basalt, crystalline rock and salt. Development of waste package designs for incorporation in mined salt repositories is discussed. The three pertinent high-level waste forms are: spent fuel, as disassembled and close-packed fuel pins in a mild steel canister; commercial high-level waste (CHLW), as borosilicate glass in stainless-steel canisters; defence high-level waste (DHLW), as borosilicate glass in stainless-steel canisters. The canisters are production and handling items only. They have no planned long-term isolation function. Each waste form requires a different approach in package design. However, the general geometry and the materials of the three designs are identical. The selected waste package design is an overpack of low carbon steel with a welded closure. This container surrounds the waste forms. Studies to better define brine quantity and composition, radiation effects on the salt and brines, long-term corrosion behaviour of the low carbon steel, and the leaching behaviour of the spent fuel and borosilicate glass waste forms are continuing. (author)

Overview of high-level waste management accomplishments

International Nuclear Information System (INIS)

Lawroski, H.; Berreth, J.R.; Freeby, W.A.

1980-01-01

Storage of power reactor spent fuel is necessary at present because of the lack of reprocessing operations particularly in the U.S. By considering the above solidification and storage scenario, there is more than reasonable assurance that acceptable, stable, low heat generation rate, solidified waste can be produced, and safely disposed. The public perception of no waste disposal solutions is being exploited by detractors of nuclear power application. The inability to even point to one overall system demonstration lends credibility to the negative assertions. By delaying the gathering of on-line information to qualify repository sites, and to implement a demonstration, the actions of the nuclear power detractors are self serving in that they can continue to point out there is no demonstration of satisfactory high-level waste disposal. By maintaining the liquid and solidified high-level waste in secure above ground storage until acceptable decay heat generation rates are achieved, by producing a compatible, high integrity, solid waste form, by providing a second or even third barrier as a compound container and by inserting the enclosed waste form in a qualified repository with spacing to assure moderately low temperature disposal conditions, there appears to be no technical reason for not progressing further with the disposal of high-level wastes and needed implementation of the complete nuclear power fuel cycle

Future health physics prospects in high-level nuclear waste management

International Nuclear Information System (INIS)

Waite, D.A.; Mayberry, J.J.

1986-01-01

The objective of this presentation is to provide an overview of health physics activities anticipated to be required at a high-level nuclear waste repository and to project the numbers of health physics personnel expected to be required to carry out these activities. Health physics personnel receiving consideration in the projections include the health physics manager, shift supervisors, area supervisors, health physicists, and technologists. Phases of the repository addressed are construction, operation, retrieval, and decommissioning. Specific topics discussed in the process of developing the projections are: (a) the basic features of a geologic repository, (b) the staffing requirements of such a repository, (c) health physics involvement in repository operations, and (d) the anticipated schedule for operation of repositories in the United States. A quantitative assessment of future health physics prospects in high-level nuclear waste management is included

Strategies for high-level radioactive waste management: the U.S. experience

International Nuclear Information System (INIS)

Cotton, T.A.

1984-01-01

Technology exists or is under development for the safe, retrievable storage of spent fuel from commercial nuclear reactors and high-level waste from reprocessing that fuel, for many decades, and no insuperable scientific obstacles to permanent disposal of spent fuel or high-level waste in geologic repositories have been identified. However, there are significant institutional obstacles to developing such repositories: strong local opposition to siting and the requirement for a sustained commitment of money and skilled manpower over a period of decades. These create strong incentives to defer the political and economic costs of developing disposal facilities by using less expensive interim storage; yet continued deferral may affect the acceptability of nuclear power. Thus the principal strategic policy issue in high-level waste management is how rapidly to develop disposal facilities. Some countries plan decades of storage before choosing a repository site or a disposal technology, while the United States has enacted a law requiring operation of a geologic repository by 1998. This paper discusses waste management strategic issues and major provisions of the U.S. law, emphasizing those measures dealing with the institutional obstacles to developing geologic repositories. (author)

Low- and intermediate-level waste repository-induced effects

Energy Technology Data Exchange (ETDEWEB)

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

2016-10-15

This status report aims at describing and assessing the interactions of the radioactive waste emplaced in a low- and intermediate level waste (L/ILW) repository with the engineered materials and the Opalinus Clay host rock. The Opalinus Clay has a thickness of about 100 m in the proposed siting regions. Among other things the results are used to steer the RD and D programme of NAGRA. The repository-induced effects considered in this report are of the following broad types: - Thermal effects: i.e. effects arising principally from the heat generated by the waste and the setting of cement. - Rock-mechanical effects: i.e. effects arising from the mechanical disturbance to the rock caused by the excavation of the emplacement caverns and other underground structures. - Hydraulic and gas-related effects: i.e. the effects of repository resaturation and of gas generation, e.g. due to the corrosion of metals within the repository, on the host rock and engineered barriers. - Chemical effects: i.e. chemical interactions between the waste, the engineered materials and the host rock. Deep geological repositories are designed to avoid or mitigate the impact of potentially detrimental repository-induced effects on long-term safety. For the repository under consideration in the present report, an assessment of those repository-induced effects that remain shows that detrimental chemical and mechanical impacts are largely confined to the rock adjacent to the excavations, thermal impacts are minimal and gas effects can be mitigated by appropriate design measures to reduce gas production and provide pathways for gas transport that limit gas pressure build-up (engineered gas transport system, or EGTS). Specific measures that are part of the current reference design are discussed in relation to their significance with respect to repository-induced effects. The disposal system described in this report provides a system of passive barriers with multiple safety functions. The disposal

Low- and intermediate-level waste repository-induced effects

International Nuclear Information System (INIS)

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

2016-10-01

This status report aims at describing and assessing the interactions of the radioactive waste emplaced in a low- and intermediate level waste (L/ILW) repository with the engineered materials and the Opalinus Clay host rock. The Opalinus Clay has a thickness of about 100 m in the proposed siting regions. Among other things the results are used to steer the RD and D programme of NAGRA. The repository-induced effects considered in this report are of the following broad types: - Thermal effects: i.e. effects arising principally from the heat generated by the waste and the setting of cement. - Rock-mechanical effects: i.e. effects arising from the mechanical disturbance to the rock caused by the excavation of the emplacement caverns and other underground structures. - Hydraulic and gas-related effects: i.e. the effects of repository resaturation and of gas generation, e.g. due to the corrosion of metals within the repository, on the host rock and engineered barriers. - Chemical effects: i.e. chemical interactions between the waste, the engineered materials and the host rock. Deep geological repositories are designed to avoid or mitigate the impact of potentially detrimental repository-induced effects on long-term safety. For the repository under consideration in the present report, an assessment of those repository-induced effects that remain shows that detrimental chemical and mechanical impacts are largely confined to the rock adjacent to the excavations, thermal impacts are minimal and gas effects can be mitigated by appropriate design measures to reduce gas production and provide pathways for gas transport that limit gas pressure build-up (engineered gas transport system, or EGTS). Specific measures that are part of the current reference design are discussed in relation to their significance with respect to repository-induced effects. The disposal system described in this report provides a system of passive barriers with multiple safety functions. The disposal

Radiation transport in high-level waste form

International Nuclear Information System (INIS)

Arakali, V.S.; Barnes, S.M.

1992-01-01

The waste form selected for vitrifying high-level nuclear waste stored in underground tanks at West Valley, NY is borosilicate glass. The maximum radiation level at the surface of a canister filled with the high-level waste form is prescribed by repository design criteria for handling and disposition of the vitrified waste. This paper presents an evaluation of the radiation transport characteristics for the vitreous waste form expected to be produced at West Valley and the resulting neutron and gamma dose rates. The maximum gamma and neutron dose rates are estimated to be less than 7500 R/h and 10 mRem/h respectively at the surface of a West Valley canister filled with borosilicate waste glass

Unsaturated flow and transport through fractured rock related to high-level waste repositories

International Nuclear Information System (INIS)

Evans, D.D.; Rasmussen, T.C.

1991-01-01

Research results are summarized for a US Nuclear Regulatory Commission contract with the University of Arizona focusing on field and laboratory methods for characterizing unsaturated fluid flow and solute transport related to high-level radioactive waste repositories. Characterization activities are presented for the Apache Leap Tuff field site. The field site is located in unsaturated, fractured tuff in central Arizona. Hydraulic, pneumatic, and thermal characteristics of the tuff are summarized, along with methodologies employed to monitor and sample hydrologic and geochemical processes at the field site. Thermohydrologic experiments are reported which provide laboratory and field data related to the effects conditions and flow and transport in unsaturated, fractured rock. 29 refs., 17 figs., 21 tabs

Ventilation System Strategy for a Prospective Korean Radioactive Waste Repository

International Nuclear Information System (INIS)

Kim, Jin; Kwon, Sang Ki

2005-01-01

In the stage of conceptual design for the construction and operation of the geologic repository for radioactive wastes, it is important to consider a repository ventilation system which serves the repository working environment, hygiene and safety of the public at large, and will allow safe maintenance like moisture content elimination in repository for the duration of the repositories life, construction/operation/closure, also allowing safe waste transportation and emplacement. This paper describes the possible ventilation system design criteria and requirements for the prospective Korean radioactive waste repositories with emphasis on the underground rock cavity disposal method in the both cases of low and medium-level and high-level wastes. It was found that the most important concept is separate ventilation systems for the construction (development) and waste emplacement (storage) activities. In addition, ventilation network system modeling, natural ventilation, ventilation monitoring systems and real time ventilation simulation, and fire simulation and emergency system in the repository are briefly discussed.

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

International Nuclear Information System (INIS)

Min, Kibok

2011-01-01

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

High-level waste processing and disposal

International Nuclear Information System (INIS)

Crandall, J.L.; Krause, H.; Sombret, C.; Uematsu, K.

1984-01-01

The national high-level waste disposal plans for France, the Federal Republic of Germany, Japan, and the United States are covered. Three conclusions are reached. The first conclusion is that an excellent technology already exists for high-level waste disposal. With appropriate packaging, spent fuel seems to be an acceptable waste form. Borosilicate glass reprocessing waste forms are well understood, in production in France, and scheduled for production in the next few years in a number of other countries. For final disposal, a number of candidate geological repository sites have been identified and several demonstration sites opened. The second conclusion is that adequate financing and a legal basis for waste disposal are in place in most countries. Costs of high-level waste disposal will probably add about 5 to 10% to the costs of nuclear electric power. The third conclusion is less optimistic. Political problems remain formidable in highly conservative regulations, in qualifying a final disposal site, and in securing acceptable transport routes

Selection of candidate container materials for the conceptual waste package design for a potential high level nuclear waste repository at Yucca Mountain

Energy Technology Data Exchange (ETDEWEB)

Van Konynenburg, R.A.; Halsey, W.G.; McCright, R.D.; Clarke, W.L. Jr. [Lawrence Livermore National Lab., CA (United States); Gdowski, G.E. [KMI, Inc., Albuquerque, NM (United States)

1993-02-01

Preliminary selection criteria have been developed, peer-reviewed, and applied to a field of 41 candidate materials to choose three alloys for further consideration during the advanced conceptual design phase of waste package development for a potential high level nuclear waste repository at Yucca Mountain, Nevada. These three alloys are titanium grade 12, Alloy C-4, and Alloy 825. These selections are specific to the particular conceptual design outlined in the Site Characterization Plan. Other design concepts that may be considered in the advanced conceptual design phase may favor other materials choices.

Selection of candidate container materials for the conceptual waste package design for a potential high level nuclear waste repository at Yucca Mountain

International Nuclear Information System (INIS)

Van Konynenburg, R.A.; Halsey, W.G.; McCright, R.D.; Clarke, W.L. Jr.; Gdowski, G.E.

1993-02-01

Preliminary selection criteria have been developed, peer-reviewed, and applied to a field of 41 candidate materials to choose three alloys for further consideration during the advanced conceptual design phase of waste package development for a potential high level nuclear waste repository at Yucca Mountain, Nevada. These three alloys are titanium grade 12, Alloy C-4, and Alloy 825. These selections are specific to the particular conceptual design outlined in the Site Characterization Plan. Other design concepts that may be considered in the advanced conceptual design phase may favor other materials choices

Swelling pressures of a potential buffer material for high-level waste repository

International Nuclear Information System (INIS)

Lee, Jae Owan; Cho, Won Jin; Chun, Kwan Sik

1999-01-01

The swelling pressure of a potential buffer material was measured and the effect of dry density, bentonite content and initial water content on the swelling pressure was investigated to provide the information for the selection of buffer material in a high-level waste repository. Swelling tests were carried out according to Box-Behnken's experimental design. Measured swelling pressures were in the wide range of 0.7 Kg/cm 2 to 190.2 Kg/cm 2 under given experimental conditions. Based upon the experimental data, a 3-factor polynomial swelling model was suggested to analyze the effect of dry density, bentonite content and initial water content on the swelling pressure. The swelling pressure increased with an increase in the dry density and bentonite content, while it decreased with increasing the initial water content and, beyond about 12 wt.% of the initial water content, levelled to nearly constant value. (author). 21 refs., 10 figs., 4 tabs

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

International Nuclear Information System (INIS)

Joonhong Ahn; Atsuyuki Suzuki

1993-01-01

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

Leaching of vitrified high-level-active-waste in a near reality simulated repository system

International Nuclear Information System (INIS)

Froeschen, W.; Wolf, G.K.

1987-01-01

In the FRG it is planned to vitrify the high level waste from spent fuel reprocessing and to dispose of in a salt-mine. If water penetrates into the repository a highly corrosive brine (Q-brine) will be formed and radioactive material may be leached from the glasses and transported to human environment. The corrosion system of brine, corroded steel containers of the vitrified waste, and waste-glasses was investigated under near reality conditions. Experiments in hydrothermal environment were carried out including gamma radiation of the waste-glasses and ceramic In Can Lining between glasses and metallic containments. Screening experiments by application of external cobalt-gamma-radiation showed no principal changes in leaching behaviour of simulate glasses compared to leaching without radiation. Radiation effects result in pH changes mainly which are diminished by buffer capacity of Q-brine. Lining of steel containments with ceramic fleece does not reduce leaching but retards solution of Mo and Sr into brine. Decreasing of elements Sr, Cs and Mo in the near surface area of the glass and increasing of Zr and Ti has been found to be enhanced considerably in presence of canister corrosion products in Q-brine as well as in NaCl-leaching solution. (orig.) With 13 refs., 22 figs [de

Waste inventory, waste characteristics and waste repositories in Japan

International Nuclear Information System (INIS)

Shimooka, K.

1997-01-01

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

Nuclear waste repository in basalt: preconceptual design guidelines

International Nuclear Information System (INIS)

1979-06-01

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

Nuclear waste repository in basalt: preconceptual design guidelines

Energy Technology Data Exchange (ETDEWEB)

1979-06-01

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

Radionuclide Transport in Fractured Rock: Numerical Assessment for High Level Waste Repository

Directory of Open Access Journals (Sweden)

Claudia Siqueira da Silveira

2013-01-01

Full Text Available Deep and stable geological formations with low permeability have been considered for high level waste definitive repository. A common problem is the modeling of radionuclide migration in a fractured medium. Initially, we considered a system consisting of a rock matrix with a single planar fracture in water saturated porous rock. Transport in the fracture is assumed to obey an advection-diffusion equation, while molecular diffusion is considered the dominant mechanism of transport in porous matrix. The partial differential equations describing the movement of radionuclides were discretized by finite difference methods, namely, fully explicit, fully implicit, and Crank-Nicolson schemes. The convective term was discretized by the following numerical schemes: backward differences, centered differences, and forward differences. The model was validated using an analytical solution found in the literature. Finally, we carried out a simulation with relevant spent fuel nuclide data with a system consisting of a horizontal fracture and a vertical fracture for assessing the performance of a hypothetical repository inserted into the host rock. We have analysed the bentonite expanded performance at the beginning of fracture, the quantified radionuclide released from a borehole, and an estimated effective dose to an adult, obtained from ingestion of well water during one year.

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

International Nuclear Information System (INIS)

Dennis, A.W.; Mulkin, R.

1984-01-01

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

Influence of temperature elevation on the sealing performance of a potential buffer material for a high-level radioactive waste repository

International Nuclear Information System (INIS)

Cho, W.-J.; Lee, J.-O.; Kang, C.-H.

2000-01-01

The sealing performance of buffer material in a high-level waste repository depends largely upon the hydraulic conductivity, the swelling pressure, and the dissolution of organic carbon in the buffer material. Temperature effects on these properties were evaluated. The hydraulic conductivity and the swelling pressure of compacted bentonite increase with increasing temperature, but the effect of temperature elevation is not large. The dissolution of organic carbon in bentonite also increases with increasing temperature, but the resultant aqueous concentrations of organic carbon in bentonite suspensions are less than those of deep groundwater in granite. Therefore, the organic carbon dissolved from the bentonite will not cause a significant increase in the organic carbon content of deep groundwater in the repository environment. Overall, temperature effects on the sealing performance of buffer material in a waste repository is not important, if the maximum temperature is maintained below 100 deg. C

High-level waste processing and disposal

International Nuclear Information System (INIS)

Crandall, J.L.; Krause, H.; Sombret, C.; Uematsu, K.

1984-11-01

Without reprocessing, spent LWR fuel itself is generally considered an acceptable waste form. With reprocessing, borosilicate glass canisters, have now gained general acceptance for waste immobilization. The current first choice for disposal is emplacement in an engineered structure in a mined cavern at a depth of 500-1000 meters. A variety of rock types are being investigated including basalt, clay, granite, salt, shale, and volcanic tuff. This paper gives specific coverage to the national high level waste disposal plans for France, the Federal Republic of Germany, Japan and the United States. The French nuclear program assumes prompt reprocessing of its spent fuels, and France has already constructed the AVM. Two larger borosilicate glass plants are planned for a new French reprocessing plant at La Hague. France plans to hold the glass canisters in near-surface storage for a forty to sixty year cooling period and then to place them into a mined repository. The FRG and Japan also plan reprocessing for their LWR fuels. Both are currently having some fuel reprocessed by France, but both are also planning reprocessing plants which will include waste vitrification facilities. West Germany is now constructing the PAMELA Plant at Mol, Belgium to vitrify high level reprocessing wastes at the shutdown Eurochemic Plant. Japan is now operating a vitrification mockup test facility and plans a pilot plant facility at the Tokai reprocessing plant by 1990. Both countries have active geologic repository programs. The United State program assumes little LWR fuel reprocessing and is thus primarily aimed at direct disposal of spent fuel into mined repositories. However, the US have two borosilicate glass plants under construction to vitrify existing reprocessing wastes

SPRAYED CLAY TECHNOLOGY FOR THE DEEP REPOSITORY OF HIGH-LEVEL RADIOACTIVE WASTE

Directory of Open Access Journals (Sweden)

Lucie Hausmannová

2012-07-01

Full Text Available The sealing barrier will play very important role in the Czech disposal concept of high level radioactive waste. It follows Swedish SKB3 design where granitic rock environment will host the repository. Swelling clay based materials as the most favorable for sealing purposes were selected. Such clays must fulfill certain requirements (e.g. on swelling properties, hydraulic conductivity or plasticity and must be stable for thousands of years. Better sealing behavior is obtained when the clay is compacted. Technology of the seal construction can vary according to its target dry density. Very high dry density is needed for buffer (sealing around entire canister with radioactive waste. Less strict requirements are on material backfilling the access galleries. It allows compaction to lower dry density than in case of buffer. One of potential technology for backfilling is to compact clay layers in most of the gallery profile by common compaction machines (rollers etc. and to spray clay into the uppermost part afterwards. The paper introduces the research works on sprayed clay technology performed at the Centre of Experimental Geotechnics of the Czech Technical University in Prague. Large scale in situ demonstration of filling of short drift in the Josef Gallery is also mentioned.

Proposed method for assigning metric tons of heavy metal values to defense high-level waste forms to be disposed of in a geologic repository

International Nuclear Information System (INIS)

1987-08-01

A proposed method is described for assigning an equivalent metric ton heavy metal (eMTHM) value to defense high-level waste forms to be disposed of in a geologic repository. This method for establishing a curie equivalency between defense high-level waste and irradiated commercial fuel is based on the ratio of defense fuel exposure to the typical commercial fuel exposure, MWd/MTHM. application of this technique to defense high-level wastes is described. Additionally, this proposed technique is compared to several alternate calculations for eMTHM. 15 refs., 2 figs., 10 tabs

Review of scenario selection approaches for performance assessment of high-level waste repositories and related issues

International Nuclear Information System (INIS)

Banano, E.J.; Baca, R.G.

1995-08-01

The selection of scenarios representing plausible realizations of the future conditions-with associated probabilities of occurrence-that can affect the long-term performance of a high-level radioactive waste (HLW) repository is the commonly used method for treating the uncertainty in the prediction of the future states of the system. This method, conventionally referred to as the ''scenario approach,'' while common is not the only method to deal with this uncertainty; other method ''ch as the environmental simulation approach (ESA), have also been proposed. Two of the difficulties with the scenario approach are the lack of uniqueness in the definition of the term ''scenario'' and the lack of uniqueness in the approach to formulate scenarios, which relies considerably on subjective judgments. Consequently, it is difficult to assure that a complete and unique set of scenarios can be defined for use in a performance assessment. Because scenarios are key to the determination of the long-term performance of the repository system, this lack of uniqueness can present a considerable challenge when attempting to reconcile the set of scenarios, and their level of detail, obtained using different approaches, particularly among proponents and regulators of a HLW repository

Review of scenario selection approaches for performance assessment of high-level waste repositories and related issues.

Energy Technology Data Exchange (ETDEWEB)

Banano, E.J. [Beta Corporation International, Albuquerque, NM (United States); Baca, R.G. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

1995-08-01

The selection of scenarios representing plausible realizations of the future conditions-with associated probabilities of occurrence-that can affect the long-term performance of a high-level radioactive waste (HLW) repository is the commonly used method for treating the uncertainty in the prediction of the future states of the system. This method, conventionally referred to as the ``scenario approach,`` while common is not the only method to deal with this uncertainty; other method ``ch as the environmental simulation approach (ESA), have also been proposed. Two of the difficulties with the scenario approach are the lack of uniqueness in the definition of the term ``scenario`` and the lack of uniqueness in the approach to formulate scenarios, which relies considerably on subjective judgments. Consequently, it is difficult to assure that a complete and unique set of scenarios can be defined for use in a performance assessment. Because scenarios are key to the determination of the long-term performance of the repository system, this lack of uniqueness can present a considerable challenge when attempting to reconcile the set of scenarios, and their level of detail, obtained using different approaches, particularly among proponents and regulators of a HLW repository.

Establishing the concept of buffer for a high-level radioactive waste repository: An approach

Energy Technology Data Exchange (ETDEWEB)

Lee, Jae Owan; Lee, Min Soo; Choi, Heui Joo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-12-15

The buffer is a key component of the engineered barrier system in a high-level radioactive waste (HLW) repository. The present study reviewed the requirements and functional criteria of the buffer reported in literature, and also based on the results, proposed an approach to establish a buffer concept which is applicable to an HLW repository in Korea. The hydraulic conductivity, radionuclide-retarding capacity (equilibrium distribution coefficient and diffusion coefficient), swelling pressure, thermal conductivity, mechanical properties, organic carbon content, and initialization rate were considered as major technical parameters for the functional criteria of the buffer. Domestic bentonite (Ca-bentonite) and, as an alternative, MX-80 (Na-bentonite) were proposed for the buffer of an HLW repository in Korea. The technical specifications for those proposed bentonites were set to parameter values that conservatively satisfy Korea's functional criteria for the Ca-bentonite and Swedish criteria for the Na-bentonite. The thickness of the buffer was determined by evaluating the means of shear behavior, radionuclide release, and heat conduction, which resulted in the proper buffer thickness of 0.25 to 0.5 m. However, the final thickness of the buffer should be determined by considering coupled thermal-hydraulic-mechanical evaluation and economics and engineering aspects as well.

High-Level Waste System Process Interface Description

International Nuclear Information System (INIS)

D'Entremont, P.D.

1999-01-01

The High-Level Waste System is a set of six different processes interconnected by pipelines. These processes function as one large treatment plant that receives, stores, and treats high-level wastes from various generators at SRS and converts them into forms suitable for final disposal. The three major forms are borosilicate glass, which will be eventually disposed of in a Federal Repository, Saltstone to be buried on site, and treated water effluent that is released to the environment

Performance analysis of a repository for low and intermediate level reactor waste

International Nuclear Information System (INIS)

Vieno, T.; Nordman, H.; Vuori, S.; Peltonen, E.

1987-01-01

In Finland, utilities producing nuclear energy are responsible for the management of the radioactive waste, including final disposal. As regards low and intermediate level waste, the approach has been adopted to employ the power plant sites for locations of repositories. The repositories will be excavated at the depth of about 50 to 125 m in the bedrock of the two Finnish nuclear power plant sites, Loviisa and Olkiluoto. The performance analysis presented in this paper has been carried out for the Preliminary Safety Analysis Report (PSAR) of the Olkiluoto repository. A flexible model has been developed to estimate the release of radionuclides from waste packages and their subsequent transport through the engineered barriers in the repository. Gradual degradation of the engineered barriers is accounted for by altering parameters at fixed time points. Safety margins of the disposal concept have been evaluated by including disturbed evolution scenarios in the analysis. 13 references, 10 figures, 2 tables

Suggestions on R and D work of high-level radioactive waste disposal in China

International Nuclear Information System (INIS)

Xu Guoqing

2012-01-01

The difference between repository and generic underground facilities is described. Some differences and similarities of site selection between the low and medium radioactive waste disposal, nuclear power station and high-level radioactive waste repository are also discussed here. We trend to extremely emphasize the safety of high-level radioactive waste disposal because of high toxicity, long half-life and long safety disposal period of this kind of radioactive wastes; because radioactive waste in the repository is of high specific activities and buried in depth, it would be difficult to meddle with its safety. In case of repository system being destroyed, the author considers that in the stages of regional and area site selection, the first task is to investigate regional tectonic stability. Some problems about disposal options and others are also discussed in this paper. (author)

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

Public acceptance for centralized storage and repositories of low-level waste session (Panel)

Energy Technology Data Exchange (ETDEWEB)

Lutz, H.R.

1995-12-31

Participants from various parts of the world will provide a summary of their particular country`s approach to low-level waste management and the cost of public acceptance for low-level waste management facilities. Participants will discuss the number, geographic location, and type of low-level waste repositories and centralized storage facilities located in their countries. Each will discuss the amount, distribution, and duration of funds to gain public acceptance of these facilities. Participants will provide an estimated $/meter for centralized storage facilities and repositories. The panel will include a brief discussion about the ethical aspects of public acceptance costs, approaches for negotiating acceptance, and lessons learned in each country. The audience is invited to participate in the discussion.

Perspective on methods to calculate a fee for disposal of defense high-level waste in combined (civilian/defense) repositories

International Nuclear Information System (INIS)

1986-12-01

The Department of Energy intends to send the high-level waste from defense operations to combined civilian/defense repositories for disposal. The federal government must pay a fee to cover its fair share of the cost for the disposal system. This report provides an overview perspective on the defense high-level waste (DHLW) quantities and characteristics and on potential alternatives for calculation and payment of the disposal fee. Information on the DHLW expected from government sites includes the number of waste canisters, radioactivity, thermal decay power, mass of defense reactor fuel, and total electrical energy-equivalents. Ranges in quantities are shown where different operating scenarios are being considered. Several different fee determination methods are described and fees for different quantities of waste are estimated. Information is also included on possible payment alternatives, production and shipping schedules, and credits which could be applied to the fee

Closure development for high-level nuclear waste containers for the tuff repository

International Nuclear Information System (INIS)

Robitz, E.S. Jr.; McAninch, M.D. Jr.; Edmonds, D.P.; Babcock and Wilcox Co., Alliance, OH

1990-09-01

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

Regional hydrogeological conceptual model of candidate Beishan area for high level radioactive waste disposal repository

International Nuclear Information System (INIS)

Wang Hailong; Guo Yonghai

2014-01-01

The numerical modeling of groundwater flow is an important aspect of hydrogeological assessment in siting of a high level radioactive waste disposal repository. Hydrogeological conceptual model is the basic and premise of numerical modeling of groundwater flow. Based on the hydrogeological analysis of candidate Beishan area, surface water system was created by using DEM data and the modeling area is determined. Three-dimensional hydrogeological structure model was created through GMS software. On the basis of analysis and description of boundary condition, flow field, groundwater budget and hydrogeological parameters, hydrogeological conceptual model was set up for the Beishan area. (authors)

Geohydrology surrounding a potential high-level nuclear waste repository in the Paradox Basin, Utah

International Nuclear Information System (INIS)

Brandstetter, A.; Kroitoru, L.; Andrews, R.W.; Thackston, J.W.

1984-01-01

The Gibson Dome area in the Paradox Basin in southeastern Utah has been identified as a potential location for a high-level nuclear waste repository on the basis of an adequate thickness of bedded salt formations at desirable depths, suitable topography for surface facilities, few known archaeological sites, less resource potential than otherwise similar areas, and long-term geologic and tectonic stability. The area appears also suitable from a geohydrologic viewpoint, on the basis of data collected and analyses performed to date. The upper, near-surface, geologic formations include both regionally continuous water-bearing formations and locally perched ground waters that discharge into nearby surface streams and into the Colorado River. Below the Paradox salts, the formations of interest with respect to repository safety include regionally continuous water-bearing formations, with the Leadville limestone being the principal water-transmitting unit. Flows in all water-bearing formations are essentially horizontal. If a vertical connection were established through a potential repository, hydraulic gradients indicate that the flow would first be downward from the upper to the lower formations and then laterally, principally in the Leadville formation. There are some indications that minor leakage could occur into the Colorado River as close as Cataract Canyon, about 20 to 25 km (10 to 15 miles) from a potential repository location in Davis Canyon, or into the Colorado River in Marble Canyon (Arizona), about 240 km (150 miles) to the southwest. Groundwater flow from a repository to these locations is unlikely, however, since water would first have to penetrate the essentially impermeable salt layers before it would reach the Leadville formation. 11 references, 4 figures

Some Materials Degradation Issues in the U.S. High-Level Nuclear Waste Repository Study (The Yucca Mountain Project)

Energy Technology Data Exchange (ETDEWEB)

F. Hua; P. Pasupathi; N. Brown; K. Mon

2005-09-19

The safe disposal of radioactive waste requires that the waste be isolated from the environment until radioactive decay has reduced its toxicity to innocuous levels for plants, animals, and humans. All of the countries currently studying the options for disposing of high-level nuclear waste (HLW) have selected deep geologic formations to be the primary barrier for accomplishing this isolation. In U.S.A., the Nuclear Waste Policy Act of 1982 (as amended in 1987) designated Yucca Mountain in Nevada as the potential site to be characterized for high-level nuclear waste (HLW) disposal. Long-term containment of waste and subsequent slow release of radionuclides into the geosphere will rely on a system of natural and engineered barriers including a robust waste containment design. The waste package design consists of a highly corrosion resistant Ni-based Alloy 22 cylindrical barrier surrounding a Type 316 stainless steel inner structural vessel. The waste package is covered by a mailbox-shaped drip shield composed primarily of Ti Grade 7 with Ti Grade 24 structural support members. The U.S. Yucca Mountain Project has been studying and modeling the degradation issues of the relevant materials for some 20 years. This paper reviews the state-of-the-art understanding of the degradation processes based on the past 20 years studies on Yucca Mountain Project (YMP) materials degradation issues with focus on interaction between the in-drift environmental conditions and long-term materials degradation of waste packages and drip shields within the repository system during the 10,000 years regulatory period. This paper provides an overview of the current understanding of the likely degradation behavior of the waste package and drip shield in the repository after the permanent closure of the facility. The degradation scenario discussed in this paper include aging and phase instability, dry oxidation, general and localized corrosion, stress corrosion cracking and hydrogen induced

Some Materials Degradation Issues in the U.S. High-Level Nuclear Waste Repository Study (The Yucca Mountain Project)

International Nuclear Information System (INIS)

Hua, F.; Pasupathi, P.; Brown, N.; Mon, K.

2005-01-01

The safe disposal of radioactive waste requires that the waste be isolated from the environment until radioactive decay has reduced its toxicity to innocuous levels for plants, animals, and humans. All of the countries currently studying the options for disposing of high-level nuclear waste (HLW) have selected deep geologic formations to be the primary barrier for accomplishing this isolation. In U.S.A., the Nuclear Waste Policy Act of 1982 (as amended in 1987) designated Yucca Mountain in Nevada as the potential site to be characterized for high-level nuclear waste (HLW) disposal. Long-term containment of waste and subsequent slow release of radionuclides into the geosphere will rely on a system of natural and engineered barriers including a robust waste containment design. The waste package design consists of a highly corrosion resistant Ni-based Alloy 22 cylindrical barrier surrounding a Type 316 stainless steel inner structural vessel. The waste package is covered by a mailbox-shaped drip shield composed primarily of Ti Grade 7 with Ti Grade 24 structural support members. The U.S. Yucca Mountain Project has been studying and modeling the degradation issues of the relevant materials for some 20 years. This paper reviews the state-of-the-art understanding of the degradation processes based on the past 20 years studies on Yucca Mountain Project (YMP) materials degradation issues with focus on interaction between the in-drift environmental conditions and long-term materials degradation of waste packages and drip shields within the repository system during the 10,000 years regulatory period. This paper provides an overview of the current understanding of the likely degradation behavior of the waste package and drip shield in the repository after the permanent closure of the facility. The degradation scenario discussed in this paper include aging and phase instability, dry oxidation, general and localized corrosion, stress corrosion cracking and hydrogen induced

The stability of candidate buffer materials for a low-level radioactive waste repository

International Nuclear Information System (INIS)

Torok, J.; Buckley, L.P.; Burton, G.R.; Tosello, N.B.; Maves, S.R.; Blimkie, M.E.; Donaldson, J.R.

1989-11-01

Inorganic ion-exchangers, clinoptilolite and clay, will be placed on the floor of a low-level radioactive waste repository to be built at Chalk River Nuclear Laboratories. The stability of these ion-exchange materials for a range of potential chemical environments in the repository was investigated. The leaching of waste forms and concrete and biological activity may create acidic or basic environment. The dissolution mechanisms of the ion exchangers for both acid and alkali conditions were established. Changes in distribution coefficients occurred shortly after the commencement of the treatment and were due to changes in the counter-ion content of the ion exchangers. No evidence was found to suggest gradual selective destruction of exchange sites responsible for the high distribution coefficients observed

SUMO, System performance assessment for a high-level nuclear waste repository: Mathematical models

International Nuclear Information System (INIS)

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

1992-09-01

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

Economic appraisal of deployment schedules for high-level radioactive waste repositories

International Nuclear Information System (INIS)

Hoai Linh Doan, Phuong; Duquesnoy, T.; Devezeaux de Lavergne, J.G.

2017-01-01

The deep geological repository (DGR) is considered as the definitive management solution for high-level radioactive waste (HLW). Countries defined different DGR implementation schedules, depending on their national context and political choices. We raise the question of the economic grounds of such political decisions by providing an economic analysis of different DGR schedules. We investigate the optimal timing for DGR commissioning based on available Nuclear Energy Agency (NEA) data (2013). Two scenarios are considered: -1) rescheduling the deployment of a DGR with the same initial operational period, and -2) rescheduling the deployment of a DGR with a shorter operational period, i.e. initial closure date. Given the long timescales of such projects, we also take into account the discounting effect. The first finding is that it appears more economically favorable to extend the interim storage than to dispose of the HLW immediately. Countries which chose 'immediate' disposal are willing to accept higher costs to quickly solve the problem. Another interesting result is that there is an optimal solution with respect to the length of DGR operational period and the waste flow for disposal. Based on data provided by the Organisation for Economic Cooperation and Development (OECD)/Nuclear Energy Agency (NEA), we find an optimal operating period of about 15 years with a flow of 2000 tHM/year. (authors)

Economic appraisal of deployment schedules for high-level radioactive waste repositories

Directory of Open Access Journals (Sweden)

Doan Phuong Hoai Linh

2017-01-01

Full Text Available The deep geological repository (DGR is considered as the definitive management solution for high-level waste (HLW. Countries defined different DGR implementation schedules, depending on their national context and political choices. We raise the question of the economic grounds of such political decisions by providing an economic analysis of different DGR schedules. We investigate the optimal timing for DGR commissioning based on available Nuclear Energy Agency (NEA data (2013. Two scenarios are considered: (1 rescheduling the deployment of a DGR with the same initial operational period, and (2 rescheduling the deployment of a DGR with a shorter operational period, i.e. initial closure date. Given the long timescales of such projects, we also take into account the discounting effect. The first finding is that it appears more economically favorable to extend the interim storage than to dispose of the HLW immediately. Countries which chose “immediate” disposal are willing to accept higher costs to quickly solve the problem. Another interesting result is that there is an optimal solution with respect to the length of DGR operational period and the waste flow for disposal. Based on data provided by the Organisation for Economic Cooperation and Development (OECD/Nuclear Energy Agency (NEA, we find an optimal operating period of about 15 years with a flow of 2000 tHM/year.

Shaft seals for final high-level radioactive waste repositories. ELSA. Pt. 1

International Nuclear Information System (INIS)

Kudla, W.; Schreiter, F.; Gruner, M.

2013-01-01

The state of the art in science and technology fir shaft seals with long-term stability is summarized regarding their applicability for high-level waste repository in Germany. The concepts and drafts for the shaft sealing systems ERAM, Asse, Konrad, the WIPP side, the RESEAL concept, the NAGRA concept and the project LASA are reviewed. The methodology of applying partial factors in a safety analysis is summarized and the applicability of this method for geotechnical sealing structures is confirmed. To establish geomechanical boundary conditions of the host rocks and clay stone the stress-strain behavior of the rock mass adjoining the shaft has to be identified including time-dependent thermo-mechanical processes. The general and special requirements for the design of shaft sealing systems, especially in salt rock and clay formations are described, derived from the safety requirements (BMU 2010). Finally general information needs were identified.

Characteristics of potential repository wastes

International Nuclear Information System (INIS)

Notz, K.J.

1989-01-01

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

Status report on the Nuclear Regulatory Commission regulations for land disposal of low-level radioactive wastes and geologic repository disposal of high-level wastes

International Nuclear Information System (INIS)

Browning, R.E.; Bell, M.J.; Dragonette, K.S.; Johnson, T.C.; Roles, G.W.; Lohaus, P.H.; Regnier, E.P.

1984-01-01

On 27 December 1982, the United States Nuclear Regulatory Commission (NRC) amended its regulations to provide specific requirements for licensing the land disposal of low-level radioactive wastes. The regulations establish performance objectives for land disposal of waste; technical requirements for the siting, design, operations, and closure activities for a near-surface disposal facility; technical requirements concerning waste form and classification that waste generators must meet for the land disposal of waste; institutional requirements; financial assurance requirements; and administrative and procedural requirements for licensing a disposal facility. Waste generators must comply with the waste form and classification provisions of the new rule, on 27 December 1983, one year later. During this implementation period, licensees must develop programmes to ensure compliance with the new waste form and classification provisions. The NRC is also promulgating regulations specifying the technical criteria for disposal of high-level radioactive wastes in geological repositories. The proposed rule was published for public comment in July 1981. Public comments have been received and considered by the Commission staff. The Commission will soon approve and publish a revised final rule. While the final rule being considered by the Commission is fundamentally the same as the proposed rule, provisions have been added to permit flexibility in the application of numerical criteria, some detailed design requirements have been deleted, and other changes have been made in response to comments. The rule is consistent with the recently enacted Nuclear Waste Policy Act of 1982. (author)

The challenge of long-term participatory repository governance. Lessons learned for high level radioactive waste and spent fuel

International Nuclear Information System (INIS)

Landstroem, Catharina

2012-01-01

Voluntaristic siting procedures for deep geological repositories are becoming increasingly common; they reconfigure the relationship of repositories and society in ways that have implications for the long-term governance of these facilities. This paper identifies three challenges emerging in relation to this question: principles of monitoring, repository content, and facility closure. This paper discusses them in a comparison with similar challenges being addressed in Belgian partnerships founded to facilitate the siting and design of a low- and intermediate level short lived waste repository. The empirical exploration confirms the importance of securing stakeholder engagement throughout the repository lifecycle, for which there is a need to develop knowledge about how to encourage long-term democratic governance systems.

The ramifications of a delay in the national high-level waste repository program

International Nuclear Information System (INIS)

Vance, S.A.

1988-05-01

This thesis examines the ramifications to the nuclear power industry if a national high-level waste repository is not operational by 1998 as mandated in the Nuclear Waste Policy Act. The principal effect of a delay examined here is the potential shortage of spent fuel storage. In order to assess this impact, a computer model of a nuclear utility was developed. Data for 107 US reactors was then entered into the model to assess the impact for individual facilities. This model estimates that a delay to the year 2003 will cost industry between $21.4 million and $35.8 million in 1988 dollars. Similarly, a delay to the year 2010 is estimated to have between a $85.4 million and $142.4 million impact. Four other potential effects of a delay on industry are also examined: the potential inadequacy of the Nuclear Waste Fund; an increased difficulty in obtaining licenses from the Nuclear Regulatory Commission; increased friction between industry and the Department of Energy; and a decline in public acceptance of nuclear power. This thesis also presents a framework for developing a policy to deal with the potential effects of a delay. An argument is made for a policy which includes anticipation, participation, and education. 15 refs., 6 figs., 3 tabs

The IAEA's high level radioactive waste management programme

International Nuclear Information System (INIS)

Saire, D.E.

1994-01-01

This paper presents the different activities that are performed under the International Atomic Energy Agency's (IAEA) high level radioactive waste management programme. The Agency's programme is composed of five main activities (information exchange, international safety standards, R ampersand D activities, advisory services and special projects) which are described in the paper. Special emphasis is placed on the RADioactive WAste Safety Standards (RADWASS) programme which was implemented in 1991 to document international consensus that exists on the safe management of radioactive waste. The paper also raises the question about the need for regional repositories to serve certain countries that do not have the resources or infrastructure to construct a national repository

Thermal analysis of Yucca Mountain commercial high-level waste packages

International Nuclear Information System (INIS)

Altenhofen, M.K.; Eslinger, P.W.

1992-10-01

The thermal performance of commercial high-level waste packages was evaluated on a preliminary basis for the candidate Yucca Mountain repository site. The purpose of this study is to provide an estimate for waste package component temperatures as a function of isolation time in tuff. Several recommendations are made concerning the additional information and modeling needed to evaluate the thermal performance of the Yucca Mountain repository system

Systems study of the feasibility of high-level nuclear waste fractionation for thermal stress control in a geologic repository: appendices

International Nuclear Information System (INIS)

McKee, R.W.; Elder, H.K.; McCallum, R.F.; Silviera, D.J.; Swanson, J.L.; Wiles, L.E.

1983-06-01

This study assesses the benefits and costs of fractionating the cesium and strontium (Cs/Sr) components in commercial high-level waste (HLW) to a separate waste stream for the purpose of reducing geologic-repository thermal stresses in the region of the HLW. The major conclusion is that the Cs/Sr fractionation concept offers the prospect of a substantial total system cost advantage for HLW disposal if reduced HLW package temperatures in a basalt repository are desired. However there is no cost advantage if currently designated maximum design temperatures are acceptable. Aging the HLW for 50 to 100 years can accomplish similar results at equivalent or lower costs. Volume II contains appendices for: (1) thermal analysis supplement; (2) fractionation process experimental results supplement; (3) cost analysis supplement; and (4) radiological risk analysis supplement

Qualifying concrete for a low-level waste repository

International Nuclear Information System (INIS)

Philipose, K.E.

1990-06-01

A waste repository for the belowground disposal of low-level radioactive waste, labelled IRUS (Intrusion Resistant Underground Structure), is planned at Chalk River Nuclear Laboratories. It relies greatly on the durability of concrete for a minimum of 500 years of service life. A research program based on laboratory testing to design a durable concrete and predict its useful engineered service life is in progress. Durability of concrete depends on its resistance of deterioration from both internal and external causes. Since the rate of degradation depends to a major extent on the rate of ingress of aggressive ions into concrete, laboratory testing is in progress to establish the diffusion rates of ions, especially chlorides, sulphate and carbonate ions. A total of 1000 concrete specimens and 500 paste specimens are being exposed at 22 and 45 degrees C to twenty-five different combinations of corrosive agents, including CO 2 . Procedures to measure the ionic profile and to determine the factors controlling diffusion of ions in the various concretes have been developed. The paper presents the initial results from the research program and the longevity predictions to qualify concretes for the IRUS waste repository, based on twelve months of diffusion testing on laboratory specimens

Perspective on demonstrations of compliance for high-level waste disposal

International Nuclear Information System (INIS)

Kocher, D.C.; Smith, E.D.; O'Kelly, G.D.; Sjoreen, A.L.

1984-01-01

This paper discusses a perspective which we have developed on the problem of demonstrating compliance of high-level waste repositories with system performance standards. Our viewpoint arises from two primary concerns - first, that the US Environmental Protection Agency's proposed environmental standard for high-level waste disposal appears to require demonstrations of compliance which are incompatible with scientific knowledge, and, second, that the federal agencies involved in the licensing process may not appreciate fully the extent of unquantifiable and uresolvable uncertainty in repository performance-assessment models. We propose a general approach to demonstrations of compliance which we feel is compatible with the kinds of technical information that will be available for judging repository performance. Our approach emphasizes the importance of investigation alternative conceptual models and lines of reasoning in evaluating repository performance and the importance of subjective scientific judgment in the desision-making process. 24 references, 1 figure

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

International Nuclear Information System (INIS)

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

2006-01-01

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

Perceived risk, stigma, and potential economic impacts of a high-level nuclear waste repository in Nevada

International Nuclear Information System (INIS)

Slovic, P.; Layman, M.; Kraus, N.N.; Chalmers, J.; Gesel, G.; Flynn, J.

1989-07-01

This paper describes a program of research designed to assess the potential impacts of a high-level nuclear waste repository at Yucca Mountain, Nevada, upon tourism, retirement and job-related migration, and business development in Las Vegas and the state. Adverse economic impacts may be expected to result from two related social processes. One has to do with perceptions of risk and socially amplified reactions to ''unfortunate events'' associated with the repository (major and minor accidents, discoveries of radiation releases, evidence of mismanagement, attempts to sabotage or disrupt the facility, etc.). The second process that may trigger significant adverse impacts is that of stigmatization. The conceptual underpinnings of risk perception, social amplification, and stigmatization are discussed in this paper and empirical data are presented to demonstrate how nuclear images associated with Las Vegas and the State of Nevada might trigger adverse effects on tourism, migration, and business development

A conceptual frame for the development of models for the prediction of the local effects of a high level waste repository

International Nuclear Information System (INIS)

Palacios, Elias; Ferreri, J.C.

1985-01-01

Safety analyses assocciated with the elimination of radioactive wastes in rock masses assume, in all cases, the existance of wastes which will corrode the waste canisters producing the liberation of radionuclides in the rocky and their ultimate migration towards the biosphere. A conceptual discussion is presented which allows the specification to be met by the models for the prediction of the effects of the emplacement of a high level waste repository located at a depth of 500 m in a granitic rock. Furthermore, the radionuclides giving the largest contribution to the radiological impact are identified. (Author) [es

Managing the nation's commercial high-level radioactive waste

International Nuclear Information System (INIS)

Cotton, T.

1985-01-01

With the passage of the Nuclear Waste Policy Act of 1982 (NWPA), Congress for the first time established in law a comprehensive Federal policy for commercial high-level radioactive waste management, including interim storage and permanent disposal. NWPA provides sufficient authority for developing and operating a high-level radioactive waste management system based on disposal in mined geologic repositories. Authorization for other types of waste facilities will not be required unless major problems with geologic disposal are discovered, and studies to date have identified no insurmountable technical obstacles to developing geologic repositories. The NWPA requires the Department of Energy (DOE) to submit to Congress three key documents: (1) a Mission Plan, containing both a waste management plan with a schedule for transferring waste to Federal facilities and an implementation program for choosing sites and developing technologies to carry out that plan; (2) a monitored retrievable storage (MRS) proposal, to include a site-specific design for a long-term federal storage facility, an evaluation of whether such an MRS facility is needed and feasible, and an analysis of how an MRS facility would be integrated with the repository program if authorized by Congress; and (3) a study of alternative institutional mechanisms for financing and managing the radioactive waste system, including the option of establishing an independent waste management organization outside of DOE. The Mission Plan and the report on alternative institutional mechanisms were submitted to the 99th US Congress in 1985. The MRS proposal is to be submitted in early 1986. Each of these documents is discussed following an overview of the Nuclear Waste Policy Act of 1982

High level waste transport and disposal cost calculations for the United Kingdom

International Nuclear Information System (INIS)

Nattress, P.C.; Ward, R.D.

1992-01-01

Commercial nuclear power has been generated in the United Kingdom since 1962, and throughout that time fuel has been reprocessed giving rise to high level waste. This has been managed by storing fission products and related wastes as highly active liquor, and more recently by a program of vitrification and storage of the glass blocks produced. Government policy is that vitrified high level waste should be stored for at least 50 years, which has the technical advantage of allowing the heat output rate of the waste to fall, making disposal easier and cheaper. Thus, there is no immediate requirement to develop a deep geological repository in the UK, but the nuclear companies do have a requirement to make financial provision out of current revenues for high level waste disposal at a future repository. In 1991 the interested organizations undertook a new calculation of costs for such provisions, which is described here. The preliminary work for the calculation included the assumption of host geology characteristics, a compatible repository concept including overpacking, and a range of possible nuclear programs. These have differing numbers of power plants, and differing mixes of high level waste from reprocessing and spent fuel for direct disposal. An algorithm was then developed so that the cost of high level waste disposal could be calculated for any required case within a stated envelope of parameters. An Example Case was then considered in detail leading to the conclusion that a repository to meet the needs of a constant UK nuclear economy up to the middle of the next century would have a cash cost of UK Pounds 1194M (US$2011M). By simple division the cost to a kWh of electricity is UK Pounds 0.00027 (0.45 US mil). (author)

Comprehensive comparison of preselected regions for a high level radioactive waste repository: a subjective quantitative evaluation method

International Nuclear Information System (INIS)

Wang Ju; Zong Zihua; Jin Yuanxin; Zhu Pengfei; Su Rui; Chen Weiming

2012-01-01

Based on the comprehensive features of the 6 preselected regions (Northwest China, Southwest China East China, South China, Inner Mongolia, Xinjiang regions) for China's high level radioactive waste repository, this paper uses the subjective quantitative method to evaluate the weight of each site selection criterion and provides the scores of each region. The results shows that the future natural changes and the hydrogeological conditions are considered as the most important natural siting criteria, while the social impact and human activities are the most important social siting criteria. According to the scores, the priority order of the regions are Northwest China, Xinjiang, Inner Mongolia, South China, East China, Southwest China. On the whole, the scores of' the regions in western China (Northwest China, Xinjiang and Inner Mongolia) are higher than those in eastern China (South China, East China Southwest China), which obviously shows that the participated experts considers that the disposal of high level waste in west China is more favorable than in east China. (authors)

High-level radioactive waste management in the United States. Background and status: 1996

International Nuclear Information System (INIS)

Dyer, J.R.

1996-01-01

The US high-level radioactive waste disposal program is investigating a site at Yucca Mountain, Nevada, to determine whether or not it is a suitable location for the development of a deep mined geologic repository. At this time, the US program is investigating a single site, although in the past, the program involved successive screening and comparison of alternate locations. The United States civilian reactor programs do not reprocess spent fuel; the high-level waste repository will be designed for the emplacement or spent fuel and a limited amount of vitrified high-level wastes from previous reprocessing in the US. The legislation enabling the US program also contains provisions for a Monitored Retrievable Storage facility, which could provide temporary storage of spent fuel accepted for disposal, and improve the flexibility of the repository development schedule

Design perspectives for the low and intermediate level radioactive waste repository in Korea

International Nuclear Information System (INIS)

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

2007-01-01

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

Modeling by GASP-IV simulation of high-level nuclear waste disposal

International Nuclear Information System (INIS)

Kurstedt, H.A. Jr.; DePorter, E.L.; Turek, J.L.; Funk, S.K.; Rasbach, C.E.

1981-01-01

High-level nuclear waste generated by defense-oriented and commercial nuclear energy activities are to be stored ultimately in underground repositories. Research continues on the waste-form and waste-form processing. DOE managers must coordinate the results of this research, the capacities and availability times of the permanent geologic storage repositories, and the capacities and availability times of interim storage facilities (pending availability of permanent repositories). Comprehensive and active DOE program-management information systems contain predicted generation of nuclear wastes from defense and commercial activities; milestones on research on waste-forms; and milestones on research and development, design, acquisition, and construction of facilities and repositories. A GASP IV simulation model is presented which interfaces all of these data. The model accepts alternate management decisions; relates all critical milestones, all research and development data, and the generation of waste nuclear materials; simulates the passage of time; then, predicts the impact of those alternate decisions on the availability of storage capacity for waste nuclear materials. 3 references, 3 figures

Effect of buffer thickness on the retardation of radionuclide release from the high-level waste repository

International Nuclear Information System (INIS)

Cho, Won Jin; Lee, Jae Owan; Kang, Chul Hyung; Han, Kyung Won

2000-12-01

The radionuclide release from buffer in the high-level waste repository to the surrounding host rock was assessed, and the effect of the radial buffer thickness on the release rate was analyzed. The total release rates decrease sharply with increasing radial buffer thickness up to 0.25 m, and decrease moderately at the buffer thickness between 0.25 m and 0.5 m. But increasing the radial buffer thickness beyond 0.5 m has little effect in reducing radionuclide release. Therefore a radial buffer thickness between 0.25 m and 0.5 m is sufficient based on the viewpoint of radionuclide retention

Workshop material for state review of USNRC site suitability criteria for high-level radioactive waste repositories

International Nuclear Information System (INIS)

1977-08-01

The Nuclear Regulatory Commission (NRC) is developing criteria on which to judge whether a proposed site for a geologic repository is suitable for disposal of high-level nuclear wastes. To aid in its analysis and assessment, NRC is planning three early independent reviews of the site suitability criteria development effort: a peer review by experts outside of NRC; a review by the National Academy of Sciences; and a review by State officials. This document has been prepared to aid workshop participants in understanding the Preliminary Site Suitability Criteria and to prepare them to contribute to an evaluation of those criteria

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

International Nuclear Information System (INIS)

Ahagen, H.

1993-01-01

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

Experience from developed and licensing an underground repository for low and intermediate level radioactive wastes

International Nuclear Information System (INIS)

Ebel, K.; Richter, D.

1988-01-01

In the German Democratic Republic an abandoned salt mine was selected and reconstructed to serve as a central repository for low and intermediate level wastes from nuclear power plants and radioisotope production and application from all over the country. The decision to establish such a repository was based on safety and technical-economic studies performed in the 1960s. The repository is owned by the main waste producer, the nuclear plant utility. It was designed, constructed and commissioned during 1972-1978. The licensing steps included a site licence (1972), a construction licence (1974), a comissioning licence and a continuous operation licence (1979). The paper reviews the overall choice of the disposal option, the responsibilities in radioactive waste management, the licensing and surveillance activities, the methods for transport and disposal, and the waste acceptance criteria established for the repository. (author)

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

International Nuclear Information System (INIS)

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

1994-11-01

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

Reinforced concrete in the intermediable-level nuclear waste repository

International Nuclear Information System (INIS)

Duffo, Gustavo

2009-01-01

The National Atomic Energy Commission (CNEA) is responsible for developing the nuclear waste disposal management programme. This programme contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The proposed model is a near-surface monolithic repository similar to those in operation in El Cabril, Spain. The design of this type of repository is based on the use of multiple, independent and redundant barriers and the model foresees a period of 300 years of institutional post-closure control. Since the vault and cover are major components of the engineered barriers, the durability of these concrete structures is an important aspect for the facility integrity. This work presents laboratory investigations performed on the corrosion susceptibility of steel rebars embedded in two different types of high performance reinforced concretes, recently developed by the National Institute of Industrial Technology (Argentine). Concretes were made with cement with Blast Furnace Slag (CAH) and Silica Fume cement (CAH + SF). The aim of this work is to predict the service life of the intermediate level radioactive waste disposal vaults from data obtained from electrochemical techniques. Besides, the diffusion coefficients of aggressive species, such as chloride and carbon dioxide, were also determined. On the other hand, data obtained with corrosion sensors embedded in a vault prototype is also included. These sensors allow on-line measurements of several parameters related to the corrosion process such as rebar corrosion potential and corrosion current density; incoming oxygen flow that reaches the metal surface; concrete electrical resistivity; chloride concentration and internal concrete temperature. All the information obtained from both, laboratory tests and sensors will be used for the final design of the container in order to achieve a service life more or equal than the foreseen durability for this type of

Report on the evaluation under the Act No 24/2006 of Coll. Environmental Impact Assessment Law Extension of National Radioactive Waste Repository in Mochovce for disposal low-level radioactive waste and construction of very low-level radioactive waste repository

International Nuclear Information System (INIS)

Hanusik, V.; Moravek, J.; Kusovska, Z.

2011-01-01

The report elaborated assessment of the environmental impact of extension of the National Radioactive Waste Repository in Mochovce for disposal of low and intermediate level radioactive wastes. Within this repository also the premises for very low level radioactive waste deposition should be built. The assessment report was prepared according to the Act no. 24/2006 Coll, as amended 'On the assessment of environmental impacts' Annex No. 11 upon The scope of assessment issued by the competent authority on the basis of assessment of Intent for this action. The report was prepared in VUJE, Inc. Trnava for Nuclear and Decommissioning Company, Inc. Bratislava (JAVYS).

Spent fuel and high level waste: Chemical durability and performance under simulated repository conditions. Results of a coordinated research project 1998-2004. Part 2: Results of a previously unpublished CRP: Performance of high level waste forms and packages under repository conditions. Results of a co-ordinated research project 1991-1998

International Nuclear Information System (INIS)

2007-07-01

The objective of the CRP (Coordinated Research Projekt) on the 'Performance of High Level Waste Forms and Packages under Repository Conditions' was to contribute to the development and implementation of proper and sound technologies for HLW and spent fuel management. Special emphasis was given to the identification of various waste form properties and the study of their long term durability in simulated repository conditions. Another objective was to promote the co-operation and exchange of information between Member States on experimental concerning behaviour of the waste form. The CRP was composed of research contracts and agreements with Argentina, Australia, Belgium, Canada, China, Czech Republic, Finland, France, Germany, India, Japan, Russia, and the United States of America. The publication includes 14 individual contributions of the participants to the CRP, which are indexed separately.

Overview: Defense high-level waste technology program

International Nuclear Information System (INIS)

Shupe, M.W.; Turner, D.A.

1987-01-01

Defense high-level waste generated by atomic energy defense activities is stored on an interim basis at three U.S. Department of Energy (DOE) operating locations; the Savannah River Plant in South Carolina, the Hanford Site in Washington, and the Idaho National Engineering Laboratory in Idaho. Responsibility for the permanent disposal of this waste resides with DOE's Office of Defense Waste and Transportation Management. The objective of the Defense High-Level Wast Technology Program is to develop the technology for ending interim storage and achieving permanent disposal of all U.S. defense high-level waste. New and readily retrievable high-level waste are immobilized for disposal in a geologic repository. Other high-level waste will be stabilized in-place if, after completion of the National Environmental Policy Act (NEPA) process, it is determined, on a site-specific basis, that this option is safe, cost effective and environmentally sound. The immediate program focus is on implementing the waste disposal strategy selected in compliance with the NEPA process at Savannah River, while continuing progress toward development of final waste disposal strategies at Hanford and Idaho. This paper presents an overview of the technology development program which supports these waste management activities and an assessment of the impact that recent and anticipated legal and institutional developments are expected to have on the program

Partitioning of high level liquid waste: experiences in plant level adoption

International Nuclear Information System (INIS)

Manohar, Smitha; Kaushik, C.P.

2016-01-01

High Level Radioactive Wastes are presently vitrified in borosilicate matrices in all our back end facilities in our country. This is in accordance with internationally endorsed methodology for the safe management of high level radioactive wastes. Recent advancements in the field of partitioning technology in our group, has presented us with an opportunity to have a fresh perspective on management of high level liquid radioactive wastes streams, that emanate from reprocessing operations. This paper will highlight our experiences with respect to both partitioning studies and vitrification practices, with a focus on waste volume reduction for final disposal. Incorporation of this technique has led to the implementation of the concept of recovering wealth from waste, a marked decrease on the load of disposal in deep geological repositories and serve as a step towards the vision of transmutation of long lived radionuclides

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

International Nuclear Information System (INIS)

Heckman, R.A.

1978-11-01

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

Workshops for state review of site suitability criteria for high-level radioactive waste repositories. Discussion Group reports

International Nuclear Information System (INIS)

1977-10-01

The NRC Waste Management Program and the Office of State Programs held three regional workshops to solicit ideas from State executives and legislators on the siting and licensing procedures for high level waste repositories and to solicit comments on the NRC preliminary site suitability criteria. The workshops were held in Denver, Colorado; New Orleans, Louisiana; and Philadelphia, Pennsylvania during the period 19-30 September 1977. The reports from these workshops are contained herein. The workshops were attended by 170 invited State executives and legislators from 46 states. In addition, there were over 80 observers from diverse backgrounds including the general public, government, industry, professional consultants and university faculty. The workshops were announced in the Federal Register on September 1, 1977

Considerations for reduction of gas generation in a low-level radioactive waste repository

International Nuclear Information System (INIS)

Cho, Chan Hee; Son, Jung Kwon; Lee, Myung Chan; Song, Myung Jae

1997-01-01

In a low-level radioactive waste repository, H 2 , CO 2 , and CH 4 will be generated principally by the coupled processes of metal corrosion and microbial degradation of cellulosic waste. The metal corrosion model incorporates a three-stage process encompassing aerobic and anaerobic corrosion regimes; the microbial degradation model simulates the activities of eight different microbial populations, which are maintained as functions both of pH and of the concentrations of particular chemical species. A prediction is made for gas concentrations and generation rates over an assessment period of ten thousand years in a radioactive waste repository. The results suggest that H 2 is the principal gas generated within the radioactive waste cavern. The generation rates of CO 2 and CH 4 are likely to be insignificant by comparison with H 2 . Therefore, an effective way to decrease gas generation in a radioactive waste repository seems to be to reduce metal content since the generation rate of H 2 is most sensitive to the concentration of steel

Repository waste-handling operations, 1998

International Nuclear Information System (INIS)

Cottam, A.E.; Connell, L.

1986-04-01

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

High-level radioactive waste repositories site selection plan

International Nuclear Information System (INIS)

Castanon, A.; Recreo, F.

1985-01-01

A general vision of the high level nuclear waste (HLNW) and/or nuclear spent fuel facilities site selection processes is given, according to the main international nuclear safety regulatory organisms quidelines and the experience from those countries which have reached a larger development of their national nuclear programs. (author)

High level waste repository site suitability criteria. Environmental impact statement methodology

International Nuclear Information System (INIS)

1977-06-01

The approach (methodology) which has been developed for the preparation of the environmental impact statement (EIS) is described. A suggested outline is presented for the High Level Waste Repository Site Suitability Criteria EIS together with a detailed description of the approach to be used in preparing the EIS. In addition, a methodology is presented by which the necessary cost/benefit/risk comparisons of alternative sets of site suitability criteria can be made. The TERA environmental research data bank, a computerized data bank which contained information on current and historical licensing activities for power plants was modified to include information on generic or programmatic EIS related issues. The content of the modified data bank was utilized to develop the EIS outline presented in this report. The report recommends that a modified matrix evaluation approach be used to make the cost/benefit/risk comparisons. The suggested matrix is designed to facilitate between criteria comparative analyses of economic, environmental, sociological and radiological risk factors. The quantitative compositing of dollar cost and benefits, environmental and sociological impacts, and radiological risks is to be performed using a semi-analytical, semi-visual procedure based on the concept of ''decision surfaces.''

Expected brine movement at potential nuclear waste repository salt sites

International Nuclear Information System (INIS)

McCauley, V.S.; Raines, G.E.

1987-08-01

The BRINEMIG brine migration code predicts rates and quantities of brine migration to a waste package emplaced in a high-level nuclear waste repository in salt. The BRINEMIG code is an explicit time-marching finite-difference code that solves a mass balance equation and uses the Jenks equation to predict velocities of brine migration. Predictions were made for the seven potentially acceptable salt sites under consideration as locations for the first US high-level nuclear waste repository. Predicted total quantities of accumulated brine were on the order of 1 m 3 brine per waste package or less. Less brine accumulation is expected at domal salt sites because of the lower initial moisture contents relative to bedded salt sites. Less total accumulation of brine is predicted for spent fuel than for commercial high-level waste because of the lower temperatures generated by spent fuel. 11 refs., 36 figs., 29 tabs

The conceptual design of waste repository for radioactive waste from medical, industrial and research facilities containing comparatively high radioactivity

International Nuclear Information System (INIS)

Yamamoto, Masayuki; Hashimoto, Naro

2002-02-01

Advisory Committee on Nuclear Fuel Cycle Backend Policy reported the basic approach to the RI and Institute etc. wastes on March 2002. According to it, radioactive waste form medical, industrial and research facilities should be classified by their radioactivity properties and physical and chemical properties, and should be disposed in the appropriate types of repository with that classification. For the radioactive waste containing comparatively high radioactivity generated from reactors, NSC has established the Concentration limit for disposal. NSC is now discussing about the limit for the radioactive waste from medical, industrial and research facilities containing comparatively high radioactivity. Japan Nuclear Cycle Development Institute (JNC) preliminary studied about the repository for radioactive waste from medical, industrial and research facilities and discussed about the problems for design on H12. This study was started to consider those problems, and to develop the conceptual design of the repository for radioactive waste from medical, industrial and research facilities. Safety assessment for that repository is also performed. The result of this study showed that radioactive waste from medical, industrial and research facilities of high activity should be disposed in the repository that has higher performance of barrier system comparing with the vault type near surface facility. If the conditions of the natural barrier and the engineering barrier are clearer, optimization of the design will be possible. (author)

Analysis on regional hydrogeological condition of Beishan preselected area for high level radioactive waste disposal repository in Gansu province

International Nuclear Information System (INIS)

Guo Yonghai; Su Rui; Liu Shufen; Lu Chuanhe

2004-01-01

Based on the field investigation which has been carried out in the Beishan preselected area for high level radioactive waste repository in Gansu province during the last few years and the previous hydrogeological investigation results, the different groundwater types are divided initially and the hydrogeological features of different water-bearing media are described in this paper. Meanwhile, the preliminary evaluation of the regional hydrogeological condition of the study area is carried out. (author)

Chemical conditions in the repository for low- and intermediate-level reactor waste

International Nuclear Information System (INIS)

Snellman, M.; Uotila, H.

1984-01-01

The chemical conditions in the proposed repositories for low- and intermediate-level reactor waste at Haestholmen (IVO) and Olkiluoto (TVO) have been discussed with respect to materials introduced into the repository, their possible long-term changes and interaction with groundwater flowing into the repository. The main possible groundwater-rock interactions have been discussed, as well as the role of micro-organisms, organic acids and colloids in the estimation of the barrier integrity. Experimental and theoretical studies have been performed on the basis of the natural groundwater compositions expected at the repository sites. Main emphasis is put on the chemical parameters which might influence the integrity of the different barriers in the repository as well as on the parameters which might effect the release and transport of radionuclides from the repository

Answers to your questions on high-level nuclear waste

International Nuclear Information System (INIS)

1987-11-01

This booklet contains answers to frequently asked questions about high-level nuclear wastes. Written for the layperson, the document contains basic information on the hazards of radiation, the Nuclear Waste Management Program, the proposed geologic repository, the proposed monitored retrievable storage facility, risk assessment, and public participation in the program

Modeling transient heat transfer in nuclear waste repositories.

Science.gov (United States)

Yang, Shaw-Yang; Yeh, Hund-Der

2009-09-30

The heat of high-level nuclear waste may be generated and released from a canister at final disposal sites. The waste heat may affect the engineering properties of waste canisters, buffers, and backfill material in the emplacement tunnel and the host rock. This study addresses the problem of the heat generated from the waste canister and analyzes the heat distribution between the buffer and the host rock, which is considered as a radial two-layer heat flux problem. A conceptual model is first constructed for the heat conduction in a nuclear waste repository and then mathematical equations are formulated for modeling heat flow distribution at repository sites. The Laplace transforms are employed to develop a solution for the temperature distributions in the buffer and the host rock in the Laplace domain, which is numerically inverted to the time-domain solution using the modified Crump method. The transient temperature distributions for both the single- and multi-borehole cases are simulated in the hypothetical geological repositories of nuclear waste. The results show that the temperature distributions in the thermal field are significantly affected by the decay heat of the waste canister, the thermal properties of the buffer and the host rock, the disposal spacing, and the thickness of the host rock at a nuclear waste repository.

Reconstruction and modernization of Novi Han radioactive waste repository

International Nuclear Information System (INIS)

Kolev, I.; Dralchev, D.; Spasov, P.; Jordanov, M.

2000-01-01

This report presents briefly the most important issues of the study performed by EQE - Bulgaria. The objectives of the study are the development of conceptual solutions for construction of the following facilities in the Novi Han radioactive waste repository: an operational storage for unconditioned high level spent sources; new temporary buildings over the existing radioactive waste storage facilities; a rain-water draining system ect. The study also includes the engineering solutions for conservation of the existing facilities, currently full with high level spent sources. A 'Program for reconstruction and modernization' has been created, including the analysis of some regulation aspects concerning this program implementation. In conclusions the engineering problems of Novi Han repository are clear and appropriate solutions are available. They can be implemented in both cases of 'small' or 'large' reconstruction. The reconstruction project anyway should start with the construction of a new site infrastructure. Reconstruction and modernization of Novi Han radioactive waste repository is the only way to improve the management and safety of radioactive waste from medicine, industry and scientific research in Bulgaria

Project Guarantee 1985. Final repository for low- and intermediate-level radioactive wastes: The system of safety barriers

International Nuclear Information System (INIS)

Anon.

1985-01-01

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

Characteristics Data Base: Programmer's guide to the High-Level Waste Data Base

International Nuclear Information System (INIS)

Jones, K.E.; Salmon, R.

1990-08-01

The High-Level Waste Data Base is a menu-driven PC data base developed as part of OCRWM's technical data base on the characteristics of potential repository wastes, which also includes spent fuel and other materials. This programmer's guide completes the documentation for the High-Level Waste Data Base, the user's guide having been published previously. 3 figs

Review of science and technology for disposal of low-level waste on the seabed and high-level waste in the subseabed

International Nuclear Information System (INIS)

Anderson, D.R.; Boyer, D.G.; Hollister, C.D.

1983-01-01

In 1980 it was recommended that an effort be made to increase the scientific data base relating to the oceanographic and biological characteristic of the Northeast Atlantic dumping area. The overall safety of sea dumping operations depends on a number of factors such as the characteristics of the dumping site, the amount, composition, conditioning, and packaging of waste, and the way in which operations are organized and controlled. An NEA research and environmental surveillance program related to sea disposal of low-level radioactive waste (LLW) is proceeding. Information from these studies will apply to disposal of LLW such as reactors from nuclear submarines and contaminated soil, as well as to packaged LLW. In Sweden, construction has begun on a repository located in the granitic rock beneath the seabed. The feasibility of a concept of burying high-level radioactive waste within the geologically stable formations of the deep ocean floor is being assessed. These subseabed options for a waste repository are being considered for several reasons. The granitic rock selected for the Swedish repository has a low hydraulic gradient, thereby reducing the amount of radioactivity tht will diffuse out of the repository. The sea water that covers the repository will dilute and disperse any radioisotopes that do escape from the repository. The other nations studying the feasibility of a subseabed repository are examining the fine-grained clay formations within the stable, predictable deep-sea regions, away from the boundaries of the lithospheric plates and productive surface waters. This clay has properties that may serve to permanently isolate radioactive waste. The most important characteristics of such clays are their vertical and lateral uniformity, low permeability, very high cation retention capacity, and potential for self-healing when disturbed

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

Supply-side approach to nuclear waste repositories

International Nuclear Information System (INIS)

Harmon, L.H.

1985-01-01

The Nuclear Waste Policy Act of 1982 (NWPA) was signed into law on January 7, 1983. Its purpose was to provide for the development of repositories for the disposal of high-level radioactive waste and spent nuclear fuel, to establish a program of research, development, and demonstration regarding the disposal of high-level radioactive waste and spent nuclear fuel, and for other purposes. Its goal is to have the first waste repository operational by 1998. It is believed by many that this goal cannot possibly be met. The Act is exceedingly complex with something in it for everybody. There are serious impediments to the program - not the least of which is legislation itself. The process will cost tens of billions of dollars and, even if it does succeed, will take many years to accomplish. This paper proposes a method for getting there in 7 years while saving billions of dollars. It is a summary of a more extensive research effort by the author while attending the Industrial College of the Armed Forces

Integrating the commercial and defense high level waste programs - A utility perspective

International Nuclear Information System (INIS)

Tomonto, J.R.

1986-01-01

The Nuclear Waste Policy Act of 1982 provided that disposal of high-level wastes resulting from defense activities be included in the authorized repository unless the President determined that separate facilities are required. President Reagan approved commingling of defense and civilian wastes on April 30, 1985. The impacts of this decision on the repository schedule, civilian spent fuel acceptance rates, and cost sharing are reviewed and recommendations for resolving these issues are presented

Uncertainty and sensitivity analysis in the 2008 performance assessment for the proposed repository for high-level radioactive waste at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Helton, Jon Craig; Sallaberry, Cedric M.; Hansen, Clifford W.

2010-01-01

Extensive work has been carried out by the U.S. Department of Energy (DOE) in the development of a proposed geologic repository at Yucca Mountain (YM), Nevada, for the disposal of high-level radioactive waste. As part of this development, an extensive performance assessment (PA) for the YM repository was completed in 2008 (1) and supported a license application by the DOE to the U.S. Nuclear Regulatory Commission (NRC) for the construction of the YM repository (2). This presentation provides an overview of the conceptual and computational structure of the indicated PA (hereafter referred to as the 2008 YM PA) and the roles that uncertainty analysis and sensitivity analysis play in this structure.

Study on engineering economics of China high-level radioactive waste geological disposal

International Nuclear Information System (INIS)

Qu Jun; Guo Zongzhi; Yang Lirong; Hu Jiang

2012-01-01

In this paper, based on the research and analysis about the repository construction cost of the European, US and Japan, together with the concept design pattern of China's high level radioactive waste repository, the preliminary economic analysis of China is presented. Meanwhile, combining with China's nuclear power development layout and picking-up policy of spent fuel fund, the preliminary measurement concerning the capital resource of high level radioactive waste disposal is implemented, which contribute to the conclusion initiatively that the spent fuel fund could meet the need of the financial demand of disposal cost. (authors)

Conceptualization of a hypothetical high-level nuclear waste repository site in unsaturated, fractured tuff

International Nuclear Information System (INIS)

Parsons, A.M.; Olague, N.E.; Gallegos, D.P.

1991-01-01

Under the sponsorship of the US Nuclear Regulatory Commission (NRC), Sandia National Laboratories (SNL) is developing a performance assessment methodology for the analysis of long-term disposal and isolation of high-level nuclear wastes (HLW) in alternative geologic media. As part of this exercise, SNL created a conceptualization of ground-water flow and radionuclide transport in the far field of a hypothetical HLW repository site located in unsaturated, fractured tuff formations. This study provides a foundation for the development of conceptual mathematical, and numerical models to be used in this performance assessment methodology. This conceptualization is site specific in terms of geometry, the regional ground-water flow system, stratigraphy, and structure in that these are based on information from Yucca Mountain located on the Nevada Test Site. However, in terms of processes in unsaturated, fractured, porous media, the model is generic. This report also provides a review and evaluation of previously proposed conceptual models of unsaturated and saturated flow and solute transport. This report provides a qualitative description of a hypothetical HLW repository site in fractured tuff. However, evaluation of the current knowledge of flow and transport at Yucca Mountain does not yield a single conceptual model. Instead, multiple conceptual models are possible given the existing information

Conceptualization of a hypothetical high-level nuclear waste repository site in unsaturated, fractured tuff

Energy Technology Data Exchange (ETDEWEB)

Parsons, A.M.; Olague, N.E.; Gallegos, D.P. [Sandia National Labs., Albuquerque, NM (USA)

1991-01-01

Under the sponsorship of the US Nuclear Regulatory Commission (NRC), Sandia National Laboratories (SNL) is developing a performance assessment methodology for the analysis of long-term disposal and isolation of high-level nuclear wastes (HLW) in alternative geologic media. As part of this exercise, SNL created a conceptualization of ground-water flow and radionuclide transport in the far field of a hypothetical HLW repository site located in unsaturated, fractured tuff formations. This study provides a foundation for the development of conceptual mathematical, and numerical models to be used in this performance assessment methodology. This conceptualization is site specific in terms of geometry, the regional ground-water flow system, stratigraphy, and structure in that these are based on information from Yucca Mountain located on the Nevada Test Site. However, in terms of processes in unsaturated, fractured, porous media, the model is generic. This report also provides a review and evaluation of previously proposed conceptual models of unsaturated and saturated flow and solute transport. This report provides a qualitative description of a hypothetical HLW repository site in fractured tuff. However, evaluation of the current knowledge of flow and transport at Yucca Mountain does not yield a single conceptual model. Instead, multiple conceptual models are possible given the existing information.

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)

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

International Nuclear Information System (INIS)

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

2014-01-01

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

Topic I: Induced changes in hydrology at low-level radioactive waste repository sites: A section in Safe disposal of radionuclides in low-level radioactive-waste repository sites; Low-level radioactive-waste disposal workshop, U.S. Geological Survey, July 11-16, 1987, Big Bear Lake, Calif., Proceedings (Circular 1036)

Science.gov (United States)

Prudic, David E.; Dennehy, Kevin F.; Bedinger, Marion S.; Stevens, Peter R.

1990-01-01

Engineering practices, including the excavation of trenches, placement of waste, nature of waste forms, backfilling procedures and materials, and trench-cover construction and materials at low-level radioactive-waste repository sites greatly affect the geohydrology of the sites. Engineering practices are dominant factors in eventual stability and isolation of the waste. The papers presented relating to Topic I were discussions of the hydrogeologic setting at existing low-level radioactive-waste repository sites and changes in the hydrology induced by site operations. Papers summarizing detailed studies presented at this workshop include those at sites near Sheffield, Ill.; Oak Ridge National Laboratory, Tenn.; West Valley, N.Y.; Maxey Flats, Ky.; Barnwell, S.C.; and Beatty, Nev. 

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

International Nuclear Information System (INIS)

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

2002-01-01

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

The role of the national low level waste repository operator in delivering new solutions for the management of low level wastes in the UK - 16217

International Nuclear Information System (INIS)

Walkingshaw, Martin

2009-01-01

The UK National Low Level Waste Repository (LLWR) is located near to the village of Drigg in West Cumbria. It is the principal site for disposal of solid Low Level Radioactive Waste (LLW) in the United Kingdom. This paper describes the program of work currently being undertaken by the site's operators, (LLW Repository Ltd and its newly appointed Parent Body Organisation), to extend the life of the LLWR and reduce the overall cost of LLW management to the UK taxpayer. The current focus of this program is to prevent disposal capacity being taken up at LLWR by waste types which lend themselves to alternative treatment and/or disposition routes. The chosen approach enables consignors to segregate LLW at source into formats which allow further treatment for volume reduction or, (for wastes with lower levels of activity), consignment in the future to alternative disposal facilities. Segregated waste services are incorporated into LLW Disposal commercial agreements between the LLWR operator and waste consignors. (author)

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

International Nuclear Information System (INIS)

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

1993-01-01

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

Strategic lessons in high-level waste management planning

Energy Technology Data Exchange (ETDEWEB)

Chapman, Neil

1999-07-01

This presentation discusses some issues in the planning and execution of high-level waste (HLW) disposal. The topics are (1) Initial considerations, (2) Issues in structuring a programme, (3) Disposal concepts, (4) Geological environments, (5) Site selection and characterisation, (6) Waste transport, (7) Performance assessment methodology and application, (8) Some key issues. The options for spent fuel management can give rise to a variety of different wastes. The quantity of waste arising will affect the volume of rock required for deposition, both with respect to rock integrity and requirements for heat dissipation. A repository must not be considered in isolation from the rest of the waste management programme. The repository development plan should be supported by a schedule of activities and related funding mechanisms, implying a long-term commitment in policy terms, and should include a corresponding legal and regulatory framework. The idea that disposed waste might be retrieved by future generations for processing under new technology is discussed. Safeguards requirements on fissile material within spent fuel or any other wastes imply indefinite control. Disposal concepts include the geological environment and the engineered barrier system within it. Site selection involves several steps: regional-scale characterisation, local characterisation, hydrological studies, etc. Key issues are retrieval vs. safeguards, optimisation of repository design, reducing long programme timescales, international collaboration.

Strategic lessons in high-level waste management planning

International Nuclear Information System (INIS)

Chapman, Neil

1999-01-01

This presentation discusses some issues in the planning and execution of high-level waste (HLW) disposal. The topics are (1) Initial considerations, (2) Issues in structuring a programme, (3) Disposal concepts, (4) Geological environments, (5) Site selection and characterisation, (6) Waste transport, (7) Performance assessment methodology and application, (8) Some key issues. The options for spent fuel management can give rise to a variety of different wastes. The quantity of waste arising will affect the volume of rock required for deposition, both with respect to rock integrity and requirements for heat dissipation. A repository must not be considered in isolation from the rest of the waste management programme. The repository development plan should be supported by a schedule of activities and related funding mechanisms, implying a long-term commitment in policy terms, and should include a corresponding legal and regulatory framework. The idea that disposed waste might be retrieved by future generations for processing under new technology is discussed. Safeguards requirements on fissile material within spent fuel or any other wastes imply indefinite control. Disposal concepts include the geological environment and the engineered barrier system within it. Site selection involves several steps: regional-scale characterisation, local characterisation, hydrological studies, etc. Key issues are retrieval vs. safeguards, optimisation of repository design, reducing long programme timescales, international collaboration

Deep repositories for waste central to uranium debate

International Nuclear Information System (INIS)

Kannegieter, T.

1991-01-01

While no deep repositories for high level wastes (HLW) have yet been constructed it is shown that technology to safely entomb the wastes for tens of thousands of years already exists. The borosilicate glass (vitrification) developed in France has been accepted by all countries who are reprocessing. Meanwhile, the Australian Synroc has not yet been put into service. Synroc developers at the Australian Nuclear Science and Technology Organization believe it will be the second generation waste form. The advantages and disadvantages of both technologies are briefly discussed as well as some of the regulatory, political, legal and technical conflicts surrounding the issue of HLW repositories. 1 tab., ills

SETTLING OF SPINEL IN A HIGH-LEVEL WASTE GLASS MELTER

International Nuclear Information System (INIS)

Pavel Hrma; Pert Schill; Lubomir Nemec

2002-01-01

High-level nuclear waste is being vitrified, i.e., converted to a durable glass that can be stored in a safe repository for hundreds of thousands of years. Waste vitrification is accomplished in reactors called melters to which the waste is charged together with glass-forming additives. The mixture is electrically heated to a temperature as high as 1150 decrees C to create a melt that becomes glass on cooling

Application of sulfur concrete for solidification of radioactive wastes and building of repositories

International Nuclear Information System (INIS)

Cholerzynski, A.; Tomczak, W.; Switalski, J.

2000-01-01

The application of sulfur concrete as solidification material for radioactive wastes and as building material used in repositories have been presented. Their high shear strength, low level of leaching, and high radiation resistance decide of positive recommendation of such material for wide use in radioactive waste treatment processes and repositories building

Coupled thermo-hydro-mechanical analysis for the conceptual repository of high-level radioactive waste in China

International Nuclear Information System (INIS)

Lin, Y.M.; Wang, J.; Ke, D.; Cai, M.F.

2010-01-01

In order to safely dispose of the high-level radioactive waste (HLW), RD guide of HLW disposal was published in February 2006 in China. The spent fuel from nuclear power plants will be reprocessed first, followed by verification and final disposal. A conceptual repository 3D configuration comprises a single vertical borehole in a continuous and homogeneous hard rock, containing a canister surrounded by an over-pack and a bentonite layer, and the backfilled upper portion of the gallery using FLAC3D. To take into account in situ stress, geothermal gradient and groundwater of Beishan area, thermal relief of HLW and swelling pressure of buffer/backfill material made by GMZ01 bentonite, the TM, HM and THM evolution of the whole configuration is simulated over a period of 100 years. The results demonstrate that temperature is hardly affected by the couplings. In contrast, the influence of the couplings on the mechanical stresses is considerable. The repository has long-term stability in fully THM coupling action condition. (authors)

Comparison of selected foreign plans and practices for spent fuel and high-level waste management

International Nuclear Information System (INIS)

Schneider, K.J.; Mitchell, S.J.; Lakey, L.T.; Johnson, A.B. Jr.; Hazelton, R.F.; Bradley, D.J.

1990-04-01

This report describes the major parameters for management of spent nuclear fuel and high-level radioactive wastes in selected foreign countries as of December 1989 and compares them with those in the United States. The foreign countries included in this study are Belgium, Canada, France, the Federal Republic of Germany, Japan, Sweden, Switzerland, and the United Kingdom. All the countries are planning for disposal of spent fuel and/or high-level wastes in deep geologic repositories. Most countries (except Canada and Sweden) plan to reprocess their spent fuel and vitrify the resultant high-level liquid wastes; in comparison, the US plans direct disposal of spent fuel. The US is planning to use a container for spent fuel as the primary engineered barrier. The US has the most developed repository concept and has one of the earliest scheduled repository startup dates. The repository environment presently being considered in the US is unique, being located in tuff above the water table. The US also has the most prescriptive regulations and performance requirements for the repository system and its components. 135 refs., 8 tabs

Comparison of selected foreign plans and practices for spent fuel and high-level waste management

Energy Technology Data Exchange (ETDEWEB)

Schneider, K.J.; Mitchell, S.J.; Lakey, L.T.; Johnson, A.B. Jr.; Hazelton, R.F.; Bradley, D.J.

1990-04-01

This report describes the major parameters for management of spent nuclear fuel and high-level radioactive wastes in selected foreign countries as of December 1989 and compares them with those in the United States. The foreign countries included in this study are Belgium, Canada, France, the Federal Republic of Germany, Japan, Sweden, Switzerland, and the United Kingdom. All the countries are planning for disposal of spent fuel and/or high-level wastes in deep geologic repositories. Most countries (except Canada and Sweden) plan to reprocess their spent fuel and vitrify the resultant high-level liquid wastes; in comparison, the US plans direct disposal of spent fuel. The US is planning to use a container for spent fuel as the primary engineered barrier. The US has the most developed repository concept and has one of the earliest scheduled repository startup dates. The repository environment presently being considered in the US is unique, being located in tuff above the water table. The US also has the most prescriptive regulations and performance requirements for the repository system and its components. 135 refs., 8 tabs.

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

International Nuclear Information System (INIS)

1984-05-01

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

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

Energy Technology Data Exchange (ETDEWEB)

1984-05-01

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

Accumulated energy determination in salts rocks irradiated by means of thermoluminescence techniques: application to the high level radioactive wastes repositories analysis

International Nuclear Information System (INIS)

Dies, J.; Ortega. J.; Tarrasa. F.; Cuevas, C.

1995-01-01

The report summarizes the study carried out to develop the radiation effects on salt rocks in order to repository the high level radioactive wastes. The study is structured into 3 main aspects: 1.- Analysis of irradiation experiences in Haw project of Pet ten reactor. 2.- Irradiation of salt sample of CESAR industrial irradiator. 3.- Correlation study between the accumulated energy, termoluminescence answer and the defect concentration

Stabilities of nuclear waste forms and their geochemical interactions in repositories

International Nuclear Information System (INIS)

White, W.B.

1980-01-01

The stabilities of high-level nuclear waste forms in a repository environment are briefly discussed. The advantages and disadvantages of such waste forms as borosilicate glass, supercalcine ceramics, and synthetic minerals are presented in context with the different rock types which have been proposed as possible host rocks for repositories. It is concluded that the growing geochemical evidence favors the use of a silicate rock repository because of the effectiveness of aluminosilicate rocks as chemical barriers for most radionuclides

Managing the nation's commercial high-level radioactive waste

International Nuclear Information System (INIS)

Anon.

1985-01-01

This study presents the findings and conclusions of OTA's analysis of Federal policy for the management of commercial high-level radioactive waste. Broad in scope and balanced in approach, its coverage extends from technological and organizational questions to political ramifications...the environmental impact of building repositories...and even dealing with Indian tribes affected by repository site selection and development. Emphasis is on workable strategies for implementing the National Waste Policy Act of 1982, including a mission plan for the program...a monitored retrievable storage proposal...and a report on mechanisms for financing and managing the program. Nine appendicies are included. They furnish additional data on such topics as policymaking, history, and the system issues resolved in NWPA

Methods of Disposing Of High-Level Radioactive Waste: A Review

International Nuclear Information System (INIS)

Abumurade, K.

2002-01-01

High level nuclear waste from both commercial reactors and defense industry presents a difficult problem to the scientific community as well as the public. The solutions to this problem is still debatable both technically and ethically. There are few methods proposed for disposing of high level waste. Each method has its own advantages and disadvantages. However, the very deep underground geologic repository is the best choice for disposing of high-level radioactive wastes. The cost benefit equation of nuclear power production and its waste is discussed. However, the public should be educated about this matter to minimize the gap between them and the nuclear power community including scientists industry, and governments. (Author) 15 refs., 4 tabs., 1 fig

Robotics and remote handling concepts for disposal of high-level nuclear waste

International Nuclear Information System (INIS)

McAffee, Douglas; Raczka, Norman; Schwartztrauber, Keith

1997-01-01

This paper summarizes preliminary remote handling and robotic concepts being developed as part of the US Department of Energy's (DOE) Yucca Mountain Project. The DOE is currently evaluating the Yucca Mountain Nevada site for suitability as a possible underground geologic repository for the disposal of high level nuclear waste. The current advanced conceptual design calls for the disposal of more than 12,000 high level nuclear waste packages within a 225 km underground network of tunnels and emplacement drifts. Many of the waste packages may weigh as much as 66 tonnes and measure 1.8 m in diameter and 5.6 m long. The waste packages will emit significant levels of radiation and heat. Therefore, remote handling is a cornerstone of the repository design and operating concepts. This paper discusses potential applications areas for robotics and remote handling technologies within the subsurface repository. It also summarizes the findings of a preliminary technology survey which reviewed available robotic and remote handling technologies developed within the nuclear, mining, rail and industrial robotics and automation industries, and at national laboratories, universities, and related research institutions and government agencies

Materials Science of High-Level Nuclear Waste Immobilization

International Nuclear Information System (INIS)

Weber, William J.; Navrotsky, Alexandra; Stefanovsky, S. V.; Vance, E. R.; Vernaz, Etienne Y.

2009-01-01

With the increasing demand for the development of more nuclear power comes the responsibility to address the technical challenges of immobilizing high-level nuclear wastes in stable solid forms for interim storage or disposition in geologic repositories. The immobilization of high-level nuclear wastes has been an active area of research and development for over 50 years. Borosilicate glasses and complex ceramic composites have been developed to meet many technical challenges and current needs, although regulatory issues, which vary widely from country to country, have yet to be resolved. Cooperative international programs to develop advanced proliferation-resistant nuclear technologies to close the nuclear fuel cycle and increase the efficiency of nuclear energy production might create new separation waste streams that could demand new concepts and materials for nuclear waste immobilization. This article reviews the current state-of-the-art understanding regarding the materials science of glasses and ceramics for the immobilization of high-level nuclear waste and excess nuclear materials and discusses approaches to address new waste streams

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

National high-level waste systems analysis

International Nuclear Information System (INIS)

Kristofferson, K.; O'Holleran, T.P.

1996-01-01

Previously, no mechanism existed that provided a systematic, interrelated view or national perspective of all high-level waste treatment and storage systems that the US Department of Energy manages. The impacts of budgetary constraints and repository availability on storage and treatment must be assessed against existing and pending negotiated milestones for their impact on the overall HLW system. This assessment can give DOE a complex-wide view of the availability of waste treatment and help project the time required to prepare HLW for disposal. Facilities, throughputs, schedules, and milestones were modeled to ascertain the treatment and storage systems resource requirements at the Hanford Site, Savannah River Site, Idaho National Engineering Laboratory, and West Valley Demonstration Project. The impacts of various treatment system availabilities on schedule and throughput were compared to repository readiness to determine the prudent application of resources. To assess the various impacts, the model was exercised against a number of plausible scenarios as discussed in this paper

Basic rock properties for the thermo-hydro-mechanical analysis of a high-level radioactive waste repository

Energy Technology Data Exchange (ETDEWEB)

Kim, Jhin Wung; Kang, Chul Hyung

1999-04-01

Deep geological radioactive waste disposal is generally based on the isolation of the waste from the biosphere by multiple barriers. The host rock is one of these barriers which should provide a stable mechanical and chemical environment for the engineered barriers. In the evaluation of the safety of the high-level radioactive waste disposal systems, an important part of the safety analysis is an assessment of the coupling or interaction between thermal, hydrological, and mechanical effects. In order to do this assessment, adequate data on the characteristics of different host rocks are necessary. The properties of the rock and rock discontinuity are very complex and their values vary in a wide range. The accuracy of the result of the assessment depends on the values of these properties used. The present study is an attempt to bring together and condense data for the basic properties of various rock masses, which are needed in the thermo-hydro-mechanical analysis for the deep geological radioactive waste repository. The testing and measurement methods for these basic properties are also presented. Domestic data for deep geological media should be supplemented in the future, due to the insufficiency and the lack of accuracy of the data available at present. (author). 28 refs., 21 figs.

Basic rock properties for the thermo-hydro-mechanical analysis of a high-level radioactive waste repository

International Nuclear Information System (INIS)

Kim, Jhin Wung; Kang, Chul Hyung

1999-04-01

Deep geological radioactive waste disposal is generally based on the isolation of the waste from the biosphere by multiple barriers. The host rock is one of these barriers which should provide a stable mechanical and chemical environment for the engineered barriers. In the evaluation of the safety of the high-level radioactive waste disposal systems, an important part of the safety analysis is an assessment of the coupling or interaction between thermal, hydrological, and mechanical effects. In order to do this assessment, adequate data on the characteristics of different host rocks are necessary. The properties of the rock and rock discontinuity are very complex and their values vary in a wide range. The accuracy of the result of the assessment depends on the values of these properties used. The present study is an attempt to bring together and condense data for the basic properties of various rock masses, which are needed in the thermo-hydro-mechanical analysis for the deep geological radioactive waste repository. The testing and measurement methods for these basic properties are also presented. Domestic data for deep geological media should be supplemented in the future, due to the insufficiency and the lack of accuracy of the data available at present. (author). 28 refs., 21 figs

Economic considerations/comparisons for the disposal of defense high-level waste

International Nuclear Information System (INIS)

Leclaire, D.B.; Lazur, E.G.

1985-01-01

This paper provides a summary, in a generic sense, of the economic considerations and comparisons of permanent isolation of defense high-level waste (DHLW) in a licensed geologic repository. Topics considered include underground disposal, economic analysis, comparative evaluations, national defense, radioactive waste facilities, and licensing

The anti NPP movement in change. New challenges due to the search for a final repository for high-level radioactive waste

International Nuclear Information System (INIS)

Brunnengraeber, Achim

2013-01-01

The German Bundestag has decided on June 28th, 2013 the law on the site selection (StandAG) has been enacted as ''national consensus'' for ''social peace''. The compromise is considered to solve the polarized conflict with respect to the site for an final repository for high-level radioactive waste. New challenges result for the government and the civil society.

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

International Nuclear Information System (INIS)

Isaacs, T.

2004-01-01

Programs to manage and ultimately dispose of high-level radioactive wastes are unique from scientific and technological as well as socio-political aspects. From a scientific and technological perspective, high-level radioactive wastes remain potentially hazardous for geological time periods--many millennia--and scientific and technological programs must be put in place that result in a system that provides high confidence that the wastes will be isolated from the accessible environment for these many thousands of years. Of course, ''proof'' in the classical sense is not possible at the outset, since the performance of the system can only be known with assurance, if ever, after the waste has been emplaced for those geological time periods. Adding to this challenge, many uncertainties exist in both the natural and engineered systems that are intended to isolate the wastes, and some of the uncertainties will remain regardless of the time and expense in attempting to characterize the system and assess its performance

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

Energy Technology Data Exchange (ETDEWEB)

Isaacs, T.

2004-10-03

Programs to manage and ultimately dispose of high-level radioactive wastes are unique from scientific and technological as well as socio-political aspects. From a scientific and technological perspective, high-level radioactive wastes remain potentially hazardous for geological time periods--many millennia--and scientific and technological programs must be put in place that result in a system that provides high confidence that the wastes will be isolated from the accessible environment for these many thousands of years. Of course, ''proof'' in the classical sense is not possible at the outset, since the performance of the system can only be known with assurance, if ever, after the waste has been emplaced for those geological time periods. Adding to this challenge, many uncertainties exist in both the natural and engineered systems that are intended to isolate the wastes, and some of the uncertainties will remain regardless of the time and expense in attempting to characterize the system and assess its performance.

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

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

International Nuclear Information System (INIS)

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

2012-01-01

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

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

International Nuclear Information System (INIS)

1999-11-01

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

Granite disposal of U.S. high-level radioactive waste.

Energy Technology Data Exchange (ETDEWEB)

Freeze, Geoffrey A.; Mariner, Paul E.; Lee, Joon H.; Hardin, Ernest L.; Goldstein, Barry; Hansen, Francis D.; Price, Ronald H.; Lord, Anna Snider

2011-08-01

This report evaluates the feasibility of disposing U.S. high-level radioactive waste in granite several hundred meters below the surface of the earth. The U.S. has many granite formations with positive attributes for permanent disposal. Similar crystalline formations have been extensively studied by international programs, two of which, in Sweden and Finland, are the host rocks of submitted or imminent repository license applications. This report is enabled by the advanced work of the international community to establish functional and operational requirements for disposal of a range of waste forms in granite media. In this report we develop scoping performance analyses, based on the applicable features, events, and processes (FEPs) identified by international investigators, to support generic conclusions regarding post-closure safety. Unlike the safety analyses for disposal in salt, shale/clay, or deep boreholes, the safety analysis for a mined granite repository depends largely on waste package preservation. In crystalline rock, waste packages are preserved by the high mechanical stability of the excavations, the diffusive barrier of the buffer, and favorable chemical conditions. The buffer is preserved by low groundwater fluxes, favorable chemical conditions, backfill, and the rigid confines of the host rock. An added advantage of a mined granite repository is that waste packages would be fairly easy to retrieve, should retrievability be an important objective. The results of the safety analyses performed in this study are consistent with the results of comprehensive safety assessments performed for sites in Sweden, Finland, and Canada. They indicate that a granite repository would satisfy established safety criteria and suggest that a small number of FEPs would largely control the release and transport of radionuclides. In the event the U.S. decides to pursue a potential repository in granite, a detailed evaluation of these FEPs would be needed to inform site

Defense High Level Waste Disposal Container System Description Document

International Nuclear Information System (INIS)

Pettit, N. E.

2001-01-01

The Defense High Level Waste 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 and sealed in the surface waste handling facilities, transferred to the underground through the accesses using a rail mounted transporter, and emplaced in emplacement drifts. The defense high level waste (HLW) disposal container provides long-term confinement of the commercial HLW and defense HLW (including immobilized plutonium waste forms [IPWF]) placed within disposable canisters, and withstands the loading, transfer, emplacement, and retrieval loads and environments. US Department of Energy (DOE)-owned spent nuclear fuel (SNF) in disposable canisters may also be placed in a defense HLW disposal container along with commercial HLW waste forms, which is known as co-disposal. The Defense High Level Waste Disposal Container System provides containment of waste for a designated period of time, and limits radionuclide release. The disposal container/waste package maintains the waste in a designated configuration, withstands maximum handling and rockfall loads, limits the individual canister temperatures after emplacement, resists corrosion in the expected handling and repository environments, and provides containment of waste in the event of an accident. Defense HLW disposal containers for HLW disposal will hold up to five HLW canisters. Defense HLW disposal containers for co-disposal will hold up to five HLW canisters arranged in a ring and one DOE SNF canister inserted in the center and/or one or more DOE SNF canisters displacing a HLW canister in the ring. Defense HLW disposal containers also will hold two Multi-Canister Overpacks (MCOs) and two HLW canisters in one disposal container. The disposal container will include outer and inner cylinders, outer and inner cylinder lids, and may include a canister guide. An exterior label will provide a means by

High-Level Waste Vitrification Facility Feasibility Study

Energy Technology Data Exchange (ETDEWEB)

D. A. Lopez

1999-08-01

A ''Settlement Agreement'' between the Department of Energy and the State of Idaho mandates that all radioactive high-level waste now stored at the Idaho Nuclear Technology and Engineering Center will be treated so that it is ready to be moved out of Idaho for disposal by a compliance date of 2035. This report investigates vitrification treatment of the high-level waste in a High-Level Waste Vitrification Facility based on the assumption that no more New Waste Calcining Facility campaigns will be conducted after June 2000. Under this option, the sodium-bearing waste remaining in the Idaho Nuclear Technology and Engineering Center Tank Farm, and newly generated liquid waste produced between now and the start of 2013, will be processed using a different option, such as a Cesium Ion Exchange Facility. The cesium-saturated waste from this other option will be sent to the Calcine Solids Storage Facilities to be mixed with existing calcine. The calcine and cesium-saturated waste will be processed in the High-Level Waste Vitrification Facility by the end of calendar year 2035. In addition, the High-Level Waste Vitrification Facility will process all newly-generated liquid waste produced between 2013 and the end of 2035. Vitrification of this waste is an acceptable treatment method for complying with the Settlement Agreement. This method involves vitrifying the waste and pouring it into stainless-steel canisters that will be ready for shipment out of Idaho to a disposal facility by 2035. These canisters will be stored at the Idaho National Engineering and Environmental Laboratory until they are sent to a national geologic repository. The operating period for vitrification treatment will be from the end of 2015 through 2035.

High-Level Waste Vitrification Facility Feasibility Study

International Nuclear Information System (INIS)

D. A. Lopez

1999-01-01

A ''Settlement Agreement'' between the Department of Energy and the State of Idaho mandates that all radioactive high-level waste now stored at the Idaho Nuclear Technology and Engineering Center will be treated so that it is ready to be moved out of Idaho for disposal by a compliance date of 2035. This report investigates vitrification treatment of the high-level waste in a High-Level Waste Vitrification Facility based on the assumption that no more New Waste Calcining Facility campaigns will be conducted after June 2000. Under this option, the sodium-bearing waste remaining in the Idaho Nuclear Technology and Engineering Center Tank Farm, and newly generated liquid waste produced between now and the start of 2013, will be processed using a different option, such as a Cesium Ion Exchange Facility. The cesium-saturated waste from this other option will be sent to the Calcine Solids Storage Facilities to be mixed with existing calcine. The calcine and cesium-saturated waste will be processed in the High-Level Waste Vitrification Facility by the end of calendar year 2035. In addition, the High-Level Waste Vitrification Facility will process all newly-generated liquid waste produced between 2013 and the end of 2035. Vitrification of this waste is an acceptable treatment method for complying with the Settlement Agreement. This method involves vitrifying the waste and pouring it into stainless-steel canisters that will be ready for shipment out of Idaho to a disposal facility by 2035. These canisters will be stored at the Idaho National Engineering and Environmental Laboratory until they are sent to a national geologic repository. The operating period for vitrification treatment will be from the end of 2015 through 2035

A Deterministic Safety Assessment of a Pyro-processed Waste Repository

International Nuclear Information System (INIS)

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

2012-01-01

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

Update on the national low level radioactive waste repository study

International Nuclear Information System (INIS)

Veitch, S.M.

1997-01-01

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

Application of systems engineering to determine performance requirements for repository waste packages

International Nuclear Information System (INIS)

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

1987-01-01

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

Underground disposal of vitrified high level radioactive waste: a review of research and development

International Nuclear Information System (INIS)

1982-11-01

A review has been undertaken of the worldwide status of research and development related to the geological disposal of vitrified high level radioactive waste. The nature and quantities of vitrified high level waste that will arise from nuclear power generation in the UK have been estimated and considered. The safety case for establishing a geological repository would have to be based on predictive models, which could adequately represent the interactions and effects of a wide range of gradual processes and possible sudden events. No detailed repository design has yet been published, but the configuration currently favoured, in the UK and in most other countries, comprises a small number of vertical shafts, from which a network of horizontal tunnels would be excavated. Waste packages would be placed in holes drilled in the floors of the tunnels. The excavation of such a repository in hard crystalline rock, in a thick homogeneous formation of rock salt, or in the less plastic argillaceous formations, appears to be within the scope of present technology. Rock types available in the UK, which are likely to prove suitable for the accommodation of a repository, have been identified. The strategies and programmes for high level waste disposal in other countries have been reviewed. (U.K.)

Thermo-Hydro Mechanical Characteristics and Processes in the Clay Barrier of a High Level Radioactive Waste Repository. State of the Art Report

International Nuclear Information System (INIS)

Villar, M. V.

2004-01-01

This document is a summary of the available information on the thermo-hydro-mechanical properties of the bentonite barrier of a high-level radioactive waste repository and of the processes taking place in it during the successive repository operation phases. Mainly the thermal properties, the volume change processes (swelling and consolidation), the permeability and the water retention capacity are analysed. A review is made of the existing experimental knowledge on the modification of the these properties by the effect of temperature, water salinity, humidity and density of the bentonite, and their foreseen evolution as a consequence of the processes expected in the repository. The compiled evolution refers mostly to the FEBEX (Spain), the MX-80 (USA) and the FoCa (France) bentonite, considered as reference barrier materials in several European disposal concepts. (Author) 102 refs

Thermo-Hydro Mechanical Characteristics and Processes in the Clay Barrier of a High Level Radioactive Waste Repository. State of the Art Report

Energy Technology Data Exchange (ETDEWEB)

Villar, M. V.

2004-07-01

This document is a summary of the available information on the thermo-hydro-mechanical properties of the bentonite barrier of a high-level radioactive waste repository and of the processes taking place in it during the successive repository operation phases. Mainly the thermal properties, the volume change processes (swelling and consolidation), the permeability and the water retention capacity are analysed. A review is made of the existing experimental knowledge on the modification of the these properties by the effect of temperature, water salinity, humidity and density of the bentonite, and their foreseen evolution as a consequence of the processes expected in the repository. The compiled evolution refers mostly to the FEBEX (Spain), the MX-80 (US) and the FoCa (France) bentonite, considered as reference barrier materials in several European disposal concepts. (Author) 102 refs.

Salt Repository Project Waste Package Program Plan: Draft

International Nuclear Information System (INIS)

Carr, J.A.; Cunnane, J.C.

1986-01-01

Under the direction of the Office of Civilian Radioactive Waste Management (OCRWM) created within the DOE by direction of the Nuclear Waste Policy Act of 1982 (NWPA), the mission of the Salt Repository Project (SRP) is to provide for the development of a candidate salt repository for disposal of high-level radioactive waste (HLW) and spent reactor fuel in a manner that fully protects the health and safety of the public and the quality of the environment. In consideration of the program needs and requirements discussed above, the SRP has decided to develop and issue this SRP Waste Package Program Plan. This document is intended to outline how the SRP plans to develop the waste package design and to show, with reasonable assurance, that the developed design will satisfy applicable requirements/performance objectives. 44 refs., 16 figs., 16 tabs

Planning and Design Considerations for Geological Repository Programmes of Radioactive Waste

International Nuclear Information System (INIS)

2014-11-01

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

The disposal of high level radioactive wastes. Proposed solutions and uses in Brazil

International Nuclear Information System (INIS)

Toledo, J.F.A.

1992-06-01

The characteristics of high level radioactive waste produced in nuclear plants similar to that used in Brazil is presented. Subsequently it is described the international experience, and the way to apply such knowledge to the Brazilian situation, defining the magnitude of the problem, applying a methodology to select sites, and choosing areas for the location of a repository. Once such areas are defined, it is presented the behaviour of rock mass, similar to those found in the brazilian territory, based on the requirements for a high radioactive waste repository site. Finally, two Projects are presented for countries with lithologies similar to that of Brazil. The first one is choosing sites for a high radioactive waste repository program, and the second is an investigation of rock mass responses program. (author)

A model for the analysis of a normal evolution scenarios for a deep geological granite repository for high-level radioactive waste

International Nuclear Information System (INIS)

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

1996-01-01

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

Quality assurance requirements and methods for high level waste package acceptability

International Nuclear Information System (INIS)

1992-12-01

This document should serve as guidance for assigning the necessary items to control the conditioning process in such a way that waste packages are produced in compliance with the waste acceptance requirements. It is also provided to promote the exchange of information on quality assurance requirements and on the application of quality assurance methods associated with the production of high level waste packages, to ensure that these waste packages comply with the requirements for transportation, interim storage and waste disposal in deep geological formations. The document is intended to assist both the operators of conditioning facilities and repositories as well as national authorities and regulatory bodies, involved in the licensing of the conditioning of high level radioactive wastes or in the development of deep underground disposal systems. The document recommends the quality assurance requirements and methods which are necessary to generate data for these parameters identified in IAEA-TECDOC-560 on qualitative acceptance criteria, and indicates where and when the control methods can be applied, e.g. in the operation or commissioning of a process or in the development of a waste package design. Emphasis is on the control of the process and little reliance is placed on non-destructive or destructive testing. Qualitative criteria, relevant to disposal of high level waste, are repository dependent and are not addressed here. 37 refs, 3 figs, 2 tabs

The influence of organic materials on the near field of an intermediate level waste radioactive waste repository

International Nuclear Information System (INIS)

Wilkins, J.D.

1988-02-01

The influence of organic materials, which are present in some intermediate level wastes, on the chemistry of the near field of a radioactive waste repository is discussed. Particular attention is given to the possible formation of water soluble complexing agents formed as a result of the radiation field and chemical conditions. The present state of the research is reviewed. (author)

Health and environmental risk-related impacts of actinide burning on high-level waste disposal

International Nuclear Information System (INIS)

Forsberg, C.W.

1992-05-01

The potential health and environmental risk-related impacts of actinide burning for high-level waste disposal were evaluated. Actinide burning, also called waste partitioning-transmutation, is an advanced method for radioactive waste management based on the idea of destroying the most toxic components in the waste. It consists of two steps: (1) selective removal of the most toxic radionuclides from high-level/spent fuel waste and (2) conversion of those radionuclides into less toxic radioactive materials and/or stable elements. Risk, as used in this report, is defined as the probability of a failure times its consequence. Actinide burning has two potential health and environmental impacts on waste management. Risks and the magnitude of high-consequence repository failure scenarios are decreased by inventory reduction of the long-term radioactivity in the repository. (What does not exist cannot create risk or uncertainty.) Risk may also be reduced by the changes in the waste characteristics, resulting from selection of waste forms after processing, that are superior to spent fuel and which lower the potential of transport of radionuclides from waste form to accessible environment. There are no negative health or environmental impacts to the repository from actinide burning; however, there may be such impacts elsewhere in the fuel cycle

Postclosure risks of alternative SRP nuclear waste forms in geologic repositories

International Nuclear Information System (INIS)

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

1982-05-01

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

Mechanical properties of buffer materials for repositories of high-level nuclear waste, 2

International Nuclear Information System (INIS)

Komine, Hideo; Ogata, Nobuhide

1993-01-01

Compacted bentonites have attracted increasing attention as back filling (buffer) materials for repositories of high-level nuclear waste. However, since little has been known concerning the swelling characteristics of compacted bentonites, it is necessary to clarify the fundamental swelling characteristics and the quantitative evaluation on this characteristics is required. For this purpose, a theoretical model concerning the swelling characteristics (swelling deformation and swelling pressure) of compacted bentonites were developed. The following conclusions were drawn from this theoretical study; (1) The evaluation formula of the swelling characteristics of compacted bentonites based on the diffuse double layer theory has been proposed by combining the theoretical model and the theoretical equation to estimate the swelling characteristics of a crystal. (2) The applicability of the evaluation formula proposed in this study has been confirmed by the comparison of the experimental results with calculated results. The sensitivity of this evaluation formula has also been investigated to find that the swelling characteristics is strongly dependent on the ion concentration of pore water and on the montmorillonite content of bentonite. (author)

Effects of long-term exposure of tuffs to high-level nuclear waste-repository conditions. Preliminary report

International Nuclear Information System (INIS)

Blacic, J.; Carter, J.; Halleck, P.; Johnson, P.; Shankland, T.; Andersen, R.; Spicochi, K.; Heller, A.

1982-02-01

Tests have been performed to explore the effects of extended exposure of tuffs from the southwestern portion of the Nevada Test Site to temperatures and pressures similar to those that will be encountered in a high-level nuclear waste repository. Tuff samples ranging from highly welded, nonzeolitized to unwelded, highly zeolitized varieties were subjected to temperatures of 80, 120, and 180 0 C; confining pressures of 9.7 and 19.7 MPa; and water-pore pressures of 0.5 to 19.7 MPa for durations of 2 to 6 months. The following basic properties were measured before and after exposure and compared: tensile strength, uniaxial compressive strength, grain density, porosity, mineralogy, permeability, thermal expansion, and thermal conductivity. Depending on rock type and exposure conditions, significant changes in ambient tensile strength, compressive strength, grain density, and porosity were measured. Mineralogic examination, permeability, and thermal property measurements remain to be completed

Shale disposal of U.S. high-level radioactive waste.

Energy Technology Data Exchange (ETDEWEB)

Sassani, David Carl; Stone, Charles Michael; Hansen, Francis D.; Hardin, Ernest L.; Dewers, Thomas A.; Martinez, Mario J.; Rechard, Robert Paul; Sobolik, Steven Ronald; Freeze, Geoffrey A.; Cygan, Randall Timothy; Gaither, Katherine N.; Holland, John Francis; Brady, Patrick Vane

2010-05-01

This report evaluates the feasibility of high-level radioactive waste disposal in shale within the United States. The U.S. has many possible clay/shale/argillite basins with positive attributes for permanent disposal. Similar geologic formations have been extensively studied by international programs with largely positive results, over significant ranges of the most important material characteristics including permeability, rheology, and sorptive potential. This report is enabled by the advanced work of the international community to establish functional and operational requirements for disposal of a range of waste forms in shale media. We develop scoping performance analyses, based on the applicable features, events, and processes identified by international investigators, to support a generic conclusion regarding post-closure safety. Requisite assumptions for these analyses include waste characteristics, disposal concepts, and important properties of the geologic formation. We then apply lessons learned from Sandia experience on the Waste Isolation Pilot Project and the Yucca Mountain Project to develop a disposal strategy should a shale repository be considered as an alternative disposal pathway in the U.S. Disposal of high-level radioactive waste in suitable shale formations is attractive because the material is essentially impermeable and self-sealing, conditions are chemically reducing, and sorption tends to prevent radionuclide transport. Vertically and laterally extensive shale and clay formations exist in multiple locations in the contiguous 48 states. Thermal-hydrologic-mechanical calculations indicate that temperatures near emplaced waste packages can be maintained below boiling and will decay to within a few degrees of the ambient temperature within a few decades (or longer depending on the waste form). Construction effects, ventilation, and the thermal pulse will lead to clay dehydration and deformation, confined to an excavation disturbed zone within

Review of important rock mechanics studies required for underground high level nuclear waste repository program

Energy Technology Data Exchange (ETDEWEB)

Kwon, S.; Cho, W. J

2007-01-15

Disposal concept adapting room and pillar method, which is a confirmed technique in mining and tunnel construction for long time, has advantages at cost, safety, technical feasibility, flexibility, and international cooperation point of views. Then the important rock mechanics principals and in situ and laboratory tests for understanding the behavior of rock, buffer, and backfill as well as their interactions will be reviewed. The accurate understanding of them is important for developing a safe disposal concept and successful operation of underground repository for permanent disposal of radioactive wastes. First of all, In this study, current status of rock mechanics studies for HLW disposal in foreign countries such as Sweden, USA, Canada, Finland, Japan, and France were reviewed. After then the in situ and laboratory tests for site characterization were summarized. Furthermore, rock mechanics studies required during the whole procedure for the disposal project from repository design to the final closure will be reviewed systematically. This study will help for developing a disposal system including site selection, repository design, operation, maintenance, and closure of a repository in deep underground rock. By introducing the required rock mechanics tests at different stages, it would be helpful from the planning stage to the operation stage of a radioactive waste disposal project.

Review of important rock mechanics studies required for underground high level nuclear waste repository program

International Nuclear Information System (INIS)

Kwon, S.; Cho, W. J.

2007-01-01

Disposal concept adapting room and pillar method, which is a confirmed technique in mining and tunnel construction for long time, has advantages at cost, safety, technical feasibility, flexibility, and international cooperation point of views. Then the important rock mechanics principals and in situ and laboratory tests for understanding the behavior of rock, buffer, and backfill as well as their interactions will be reviewed. The accurate understanding of them is important for developing a safe disposal concept and successful operation of underground repository for permanent disposal of radioactive wastes. First of all, In this study, current status of rock mechanics studies for HLW disposal in foreign countries such as Sweden, USA, Canada, Finland, Japan, and France were reviewed. After then the in situ and laboratory tests for site characterization were summarized. Furthermore, rock mechanics studies required during the whole procedure for the disposal project from repository design to the final closure will be reviewed systematically. This study will help for developing a disposal system including site selection, repository design, operation, maintenance, and closure of a repository in deep underground rock. By introducing the required rock mechanics tests at different stages, it would be helpful from the planning stage to the operation stage of a radioactive waste disposal project

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

International Nuclear Information System (INIS)

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

2010-01-01

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

Standards for high level waste disposal: A sustainability perspective

International Nuclear Information System (INIS)

Dougherty, W.W.; Powers, V.; Johnson, F.X.; Cornland, D.

1999-01-01

Spent reactor fuel from commercial power stations contains high levels of plutonium, other fissionable actinides, and fission products, all of which pose serious challenges for permanent disposal because of the very long half-lives of some isotopes. The 'nuclear nations' have agreed on the use of permanent geologic repositories for the ultimate disposal of high-level nuclear waste. However, it is premature to claim that a geologic repository offers permanent isolation from the biosphere, given high levels of uncertainty, nascent risk assessment frameworks for the time periods considered, and serious intergenerational equity issues. Many have argued for a broader consideration of disposal options that include extended monitored retrievable storage and accelerator-driven transmutation of wastes. In this paper we discuss and compare these three options relative to standards that emerge from the application of sustainable development principles, namely long-lasting technical viability, intergenerational equity, rational resource allocation, and rights of future intervention. We conclude that in order to maximise the autonomy of future generations, it is imperative to leave future options more open than does permanent disposal

Safe disposal of high-level radioactive wastes

Energy Technology Data Exchange (ETDEWEB)

Ringwood, A E [Australian National Univ., Canberra. Research School of Earth Sciences

1980-10-01

Current strategies in most countries favour the immobilisation of high-level radioactive wastes in borosilicate glasses, and their burial in large, centralised, mined repositories. Strong public opposition has been encountered because of concerns over safety and socio-political issues. The author develops a new disposal strategy, based on immobilisation of wastes in an extremely resistant ceramic, SYNROC, combined with burial in an array of widely dispersed, very deep drill holes. It is demonstrated that the difficulties encountered by conventional disposal strategies can be overcome by this new approach.

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

International Nuclear Information System (INIS)

King, F.K.

2006-01-01

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

Thermal conductivity of compacted bentonite as a buffer material for a high-level radioactive waste repository

International Nuclear Information System (INIS)

Lee, Jae Owan; Choi, Heuijoo; Lee, Jong Youl

2016-01-01

Highlights: • The thermal conductivities were measured under various disposal conditions. • They were significantly influenced by the water content and dry density. • They were not sensitive to the temperature and the anisotropic structure. • A new model of thermal conductivity was proposed for the thermal analysis. - Abstract: Bentonite buffer is one of the major barrier components of a high-level radioactive waste (HLW) repository, and the thermal conductivity of the bentonite buffer is a key parameter for the thermal performance assessment of the HLW repository. This study measured the thermal conductivity of compacted bentonite as a buffer material and investigated its dependence upon various disposal conditions: the dry density, water content, anisotropic structure of the compacted bentonite, and temperature. The measurement results showed that the thermal conductivity was significantly influenced by the water content and dry density of the compacted bentonite, while there was not a significant variation with respect to the temperature. The anisotropy of the thermal conductivity had a negligible variation for an increasing dry density. The present study also proposed a geometric mean model of thermal conductivity which best fits the experimental data.

National radioactive waste repository draft EIS. 2 volumes

International Nuclear Information System (INIS)

2002-01-01

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

Bentonite as backfill in a final repository for high-level waste: chemical aspects

International Nuclear Information System (INIS)

Grauer, R.

1986-01-01

The present Nagra concept for disposal of high-level waste foresees emplacing the steel containers enclosing the borosilicate glass in tunnels at a depth of 1000 to 1500 m. These tunnels are to be backfilled with bentonite. Bentonites are suitable as a backfill due to their swelling capability, their low hydraulic conductivity and their sorption properties. This report is restricted to chemical aspects of the backfill material: swelling capability, sorption properties and long-term stability. Under repository conditions, the swelling of monmorillonite upon water inflow is primarily innercrystalline. Cation adsorption, which is important for nuclide retention in the repository, can be described by appropriate models. It can be concluded from natural analogue studies and from laboratory experiments that the properties of the backfill material will not alter significantly over a periode of 10/sup 6/ years. Nevertheless in the long term, the formulation of mixed-layer illite/monmorillonite cannot be ruled out. Such mixed-layer clays still have good swelling and sorption properties. Given the quantity ratios foreseen, no adverse changes due to radioactive decay are to be expected. The interaction between the bentonite and the container corrosion products must, in the absence of literature data, be investigated experimentally. The type of reaction products expected (iron-containing clay minerals) and the high bentonite/iron ratio lead to the conclusion that the function of the backfill need not be impaired by these processes. Because of its better stability, a calcium bentonite is preferable to the sodium variant. A low iron content is desirable because, under reducing conditions, the surface charge of the montorillonite is increased by reduction of iron(III). Organic and sulphidic contaminants should also be kept to a minimum

Influence of Groundwater Flow Rate on Nuclide Releases from Pyro-processed Waste Repository

International Nuclear Information System (INIS)

Lee, Youn Myoung; Jeong, Jong Tae

2011-01-01

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

High-level waste processing at the Savannah River Site: An update

International Nuclear Information System (INIS)

Marra, J.E.; Bennett, W.M.; Elder, H.H.; Lee, E.D.; Marra, S.L.; Rutland, P.L.

1997-01-01

The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) in Aiken, SC mg began immobilizing high-level radioactive waste in borosilicate glass in 1996. Currently, the radioactive glass is being produced as a ''sludge-only'' composition by combining washed high-level waste sludge with glass frit. The glass is poured in stainless steel canisters which will eventually be disposed of in a permanent, geological repository. To date, DWPF has produced about 100 canisters of vitrified waste. Future processing operations will, be based on a ''coupled'' feed of washed high-level waste sludge, precipitated cesium, and glass frit. This paper provides an update of the processing activities completed to date, operational/flowsheet problems encountered, and programs underway to increase production rates

Salt Repository Project waste emplacement mode decision paper: Revison 1

International Nuclear Information System (INIS)

1987-08-01

This paper provides a recommendation as to the mode of waste emplacement to be used as the current basis for site characterization activity for the Deaf Smith County, Texas, high level nuclear waste repository site. It also presents a plan for implementing the recommendation so as to provide a high level of confidence in the project's success. Since evaluations of high-level waste disposal in geologic repositories began in the 1950s, most studies emplacement in salt formations employed the vertical orientation for emplacing waste packages in boreholes in the floor of the underground facility. This orientation was used in trials at Project Salt Vault in the 1960s. The Waste Isolation Pilot Plant (WIPP) has recently settled on a combination of vertical and horizontal modes for various waste types. This paper analyzes the information available and develops a project position upon which to base current site characterization activities. The position recommended is that the SRP should continue to use the vertical waste emplacement mode as the reference design and to carry the horizontal mode as a ''passive'' alternative. This position was developed based upon the conclusions of a decision analysis, risk assessment, and cost/schedule impact assessment. 52 refs., 6 figs., 1 tab

Modeling of strongly heat-driven flow processes at a potential high-level nuclear waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Pruess, K.; Tsang, Y.

1993-01-01

Two complementary numerical models for analyzing high-level nuclear waste emplacement at Yucca Mountain have been developed. A vertical cross-sectional (X-Z) model permits a realistic representation of hydrogeologic features, such as alternating tilting layers of welded and non-welded tuffs, fault zones, and surface topography. An alternative radially symmetric (R-Z) model is more limited in its ability to describe the hydrogeology of the site, but is better suited to model heat transfer in the host rock. Our models include a comprehensive description of multiphase fluid and heat flow processes, including strong enhancements of vapor diffusion from pore-level phase change effects. The neighborhood of the repository is found to partially dry out from the waste heat. A condensation halo of large liquid saturation forms around the drying zone, from which liquid flows downward at large rates. System response to infiltration from the surface and to ventilation of mined openings is evaluated. The impact of the various flow processes on the waste isolation capabilities of the site is discussed

Modeling of strongly heat-driven flow processes at a potential high-level nuclear waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Pruess, K.; Tsang, Y.

1993-01-01

Two complementary numerical models for analyzing high-level nuclear waste emplacement at Yucca Mountain have been developed. A vertical cross-sectional (X-Z) model permits a realistic representation of hydrogeologic features, such as alternating tilting layers of welded and non-welded tuffs. fault zones, and surface topography. An alternative radially symmetric (R-Z) model is more limited in its ability to describe the hydrogeology of the site, but is better suited to model heat transfer in the host rock. Our models include a comprehensive description of multiphase fluid and heat flow processes, including strong enhancements of vapor diffusion from pore-level phase change effects. The neighborhood of the repository is found to partially dry out from the waste heat. A condensation halo of large liquid saturation forms around the drying zone, from which liquid flows downward at large rates. System response to infiltration from the surface and to ventilation of mined openings is evaluated. The impact of the various flow processes on the waste isolation capabilities of the site is discussed

Vitrification of low-level and mixed wastes

International Nuclear Information System (INIS)

Johnson, T.R.; Bates, J.K.; Feng, Xiangdong.

1994-01-01

The US Department of Energy (DOE) and nuclear utilities have large quantities of low-level and mixed wastes that must be treated to meet repository performance requirements, which are likely to become even more stringent. The DOE is developing cost-effective vitrification methods for producing durable waste forms. However, vitrification processes for high-level wastes are not applicable to commercial low-level wastes containing large quantities of metals and small amounts of fluxes. New vitrified waste formulations are needed that are durable when buried in surface repositories

Evaluation of site-generated radioactive waste treatment and disposal methods for the Yucca Mountain repository

International Nuclear Information System (INIS)

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

1989-01-01

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

Managing the nation's commercial high-level radioactive waste

International Nuclear Information System (INIS)

1985-03-01

This report presents the findings and conclusions of OTA's analysis of Federal policy for the management of commercial high-level radioactive waste. It is intended to contribute to the implementation of Nuclear Waste Policy Act of 1982 (NWPA). The major conclusion of that review is that NWPA provides sufficient authority for developing and operating a waste management system based on disposal in geologic repositories. Substantial new authority for other facilities will not be required unless major unexpected problems with geologic disposal are encountered. OTA also concludes that DOE's Draft Mission Plan published in 1984 falls short of its potential for enhancing the credibility and acceptability of the waste management program

Natural analogues to the conditions around a final repository for high-level radioactive waste

International Nuclear Information System (INIS)

Smellie, J.A.T.

1984-12-01

This report documents the proceedings resulting from a Workshop held at Lake Geneva, Wisconsin, USA, from 1-3 October, 1984. The theme of the Workshop was entitled 'Natural analogues to the conditions around a final repository for high-level radioactive waste', and was restricted to ultimate disposal in a crystalline bedrock environment. The Workshop provided an important first step in co-ordinating and focussing different national and individual interests and approaches towards natural analogue studies. One of the points highlighted at the concluding forum of the meeting was the necessity to first define the geochemical processes which are assumed to occur after disposal of the radioactive waste, and then locate suitable analogue systems which can be used to test the mechanisms of one, or a simple combination of these geochemical processes. Even accepting that the choice of which geochemical process(es) to be selected for validation will be sensitive to individual national disposal strategies, farfield radionuclide retardation mechanisms in the geosphere were considered to be a central topic of importance, and should therefore be given high priority. At this early stage in the development of natural analogue studies it was not possible to cover all the important aspects. In retrospect, the role of the models should have received more attention; bridging the gap between geoscientists and the modellers was seen as being of prime importance in future meetings of this nature. (author)

Radioactive waste repository study

International Nuclear Information System (INIS)

1978-11-01

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

Records for radioactive waste management up to repository closure: Managing the primary level information (PLI) set

International Nuclear Information System (INIS)

2004-07-01

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

The Defense Waste Processing Facility: an innovative process for high-level waste immobilization

International Nuclear Information System (INIS)

Cowan, S.P.

1985-01-01

The Defense Waste Processing Facility (DWPF), under construction at the Department of Energy's Savannah River Plant (SRP), will process defense high-level radioactive waste so that it can be disposed of safely. The DWPF will immobilize the high activity fraction of the waste in borosilicate glass cast in stainless steel canisters which can be handled, stored, transported and disposed of in a geologic repository. The low-activity fraction of the waste, which represents about 90% of the high-level waste HLW volume, will be decontaminated and disposed of on the SRP site. After decontamination the canister will be welded shut by an upset resistance welding technique. In this process a slightly oversized plug is pressed into the canister opening. At the same time a large current is passed through the canister and plug. The higher resistance of the canister/plug interface causes the heat which welds the plug in place. This process provides a high quality, reliable weld by a process easily operated remotely