[en] As a result of history Germany owns two repositories, Konrad and Morsleben, in deep geological formations licensed for LILW and one exploration mine, Gorleben, for investigating the site's suitability to erect a repository for HLW/SNF and heat generating ILW. Due to political decisions, exploration at Gorleben is interrupted presently and no waste emplacement takes place in any of the LILW repositories. The Morsleben repository for LILW now is under licensing for closure. To assess long-term safety of the repositories different safety strategies were applied linking site independent high level requirements to site specific conditions, constraints, and boundary conditions due to the type and amount of waste to be disposed of. Using the closure of the Morsleben repository as an example different safety strategies are shown leading to different technical closure concepts and multi-barrier systems. Evaluating these different closure concepts on a conceptual level qualitative criteria may be applied first, followed by performing a provisional safety assessment being quantitative approaches for deriving a first set of safety related quantitative requirements concerning the multi-barrier system and assuring that high level requirements are fulfilled. On this basis engineered barrier design is drafted and a set of criteria for evaluating their first design qualitatively is given. When assessing single barriers quantitatively to show their compliance with the derived requirements reliably, increasing knowledge in verifying the multi-barrier system as well as single barriers leads to changes of derived requirements and modifications of technical solutions regarding the engineered barriers. Within the repository project derived requirements are documented as well as design decisions. To guarantee traceability of requirement evolution and design decisions quality assurance measures are applied. However, today they solely allow traceability, active management is not possible. Finally, a brief description is given of how engineers, scientists and safety assessors having worked together up to now and their role within the projects at different project stages. A systematic approach to integrate information from engineers, scientists and safety assessors has not been applied until now. Integrating information within a repository project is a question of applying quality assurance from the start of the project. (author)

[en] Geologic repositories are sited, designed and operated to protect humans and the environment from the hazards associated with radioactive waste. Most challengingly, they are required to provide protection after their closure and over timescales that are considerably in excess of those commonly considered in most engineering projects, often up to several thousand or even a million years. This requirement is laid down in international guidance and in many national regulations. Various processes and events will drive the evolution of a repository and its environment, and hence could affect the containment and lead to possible release of radioactive substances from the repository and their migration to the surface. These processes and events are characterised by timescales ranging from a few tens or hundreds of years for transient processes associated with, for example, the re-saturation of the repository and its immediate surroundings following closure, to perhaps millions of years for changes in the geological environment. Safety assessments must consider consequences of releases of radioactive substances and verify that targets set by regulation are complied with. In order to evaluate compliance with dose or risk criteria, assumptions must be made regarding the habits of potentially exposed groups (e.g., diet, lifestyle and land use), and these may change over timescales of just a few years. The need to deal with such a wide range of timescales gives rise to a range of issues related to the methods and presentation of safety assessments and of safety cases. (author)

[en] License for the nuclear facilities such as radioactive waste repository demands documents of site characterization, environmental assessment and safety assessment. This performance will produce bulk of the relevant data. For the safe management of radioactive waste repository, data of the site and environment have to be collected and managed systematically. Particularly for the radwaste repository, which has to be institutionally controlled for a long period after closure, the data will be collected and maintained through the monitoring programme. To meet this requirement, a new programme called 'Site Information and Total Environmental data management System (SITES)' has been developed. The scope and function of the SITES is issued in data DB, safety assessment and monitoring system. In this respect, SITES is designed with two modules of the SITES Database Module (SDM) and the Monitoring and Assesment (M and A). The SDM module is composed of three sub-modules. One is the Site Information Management System (SIMS), which manages data of site characterization such as topography, geology, hydrogeology, engineering geology, etc. The other is the ENVironmental Information management System (ENVIS) and Radioactive ENVironmental Information management System (RENVIS), which manage environmental data required for environmental assessment performance. ENVIS and RENVIS covered almost whole items of environmental assessment report required by Korean government. The SDM was constructed based on Entity Relationship Diagram produced from each item. Also using ArcGIS with the spatial characteristics of the data, it enables groundwater and water property monitoring networks, etc. To be analyzed in respect of every theme. The sub-modules of M and A called the Site and Environment Monitoring System (SEMS) and the Safety Assessment System (SAS) were developed. SEMS was designed to manage the inspection records of the individual measuring instruments and facilities, and the on-lined environmental monitoring data. SAS was developed to combine various safety assessment codes in one system

[en] Institutions involved in radioactive waste management are facing a rapidly evolving environment stemming from societal changes, including new information technologies and new roles for the media. At the same time, some national programmes are moving from research and development to site selection and implementation, while other countries are reviewing and defining their policies in the waste management area. As in many other fields in which environmental and risk considerations are involved, demand for public participation in radioactive waste management decision making calls for new approaches towards involving stakeholders. (authors)

[en] The Office of Site Closure (OSC) was formed in November 1999 when the Department of Energy's (DOE's) Office of Environmental Management (EM) reorganized to focus specifically on site cleanup and closure. OSC's objective is to achieve safe and cost-effective cleanups and closures that are protective of our workers, the public, and the environment, now and in the future. Since its inception, OSC has focused on implementing a culture of safe closure, with emphasis in three primary areas: complete our responsibility for the Closure Sites Rocky Flats, Mound, Fernald, Ashtabula, and Weldon Spring; complete our responsibility for cleanup at sites where the DOE mission has been completed (examples include Battelle King Avenue and Battelle West Jefferson in Columbus, and General Atomics) or where other Departmental organizations have an ongoing mission (examples include the Brookhaven, Livermore, or Los Alamos National Laboratories, and the Nevada Test Site); and create a framework a nd develop specific business closure tools that will help sites close, such as guidance for and decisions on post-contract benefit liabilities, records retention, and Federal employee incentives for site closure. This paper discusses OSC's 2001 progress in achieving site cleanups, moving towards site closure, and developing specific business closure tools to support site closure. It describes the tools used to achieve progress towards cleanup and closure, such as the application of new technologies, changes in contracting approaches, and the development of agreements between sites and with host states. The paper also identifies upcoming challenges and explores options for how Headquarters and the sites can work together to address these challenges. Finally, it articulates OSC's new focus on oversight of Field Offices to ensure they have the systems in place to oversee contractor activities resulting in site cleanups and closures

[en] Within the Department of Energy's Office of Environmental Management (EM), the Office of Science and Technology (OST) identifies and develops innovative technologies that accelerate cleanup of high-priority environmental contamination problems and enable EM closure sites to meet closure schedules. OST manages an integrated research and development program that is essential to completing timely and cost-effective cleanup and stewardship of DOE sites. While innovative technologies can make significant contributions to the cleanup process, in some cases, EM has encountered unexpected barriers to their implementation. Technical obstacles are expected, but administrative challenges-such as regulatory, organizational, and stakeholder issues-must also be addressed. OST has found that collaborative needs identification and problem solving are essential components in overcoming these barriers. Collaboration helps EM meet its cleanup goals, close sites, and reduce the overall cost of cleanup at DOE sites nationwide. This paper presents examples of OST's collaboration efforts that expedite site closure and solve specific cleanup problems at EM sites

[en] Previous Nirex post-closure assessments of deep geological disposal have been based on the use of probabilistic safety analysis covering many millions of years. However, Nirex has also published an assessment methodology in which the assessment timescale is divided into a number of discrete periods of time (time frames). Nirex is currently at the stage of planning the next update to its generic post-closure performance assessment and is considering the merits of using an assessment methodology based on time frames, in order to improve links with operational assessments and the provision of advice on the packaging of wastes, and to encourage stakeholder dialogue. This paper has been prepared as part of Nirex's aim, wherever possible, to 'preview', or seek input from others on, its ideas for new work to generate discussion and feedback. It describes an evolution of Nirex's published assessment methodology and outlines how it could be applied in an updated post-closure performance assessment of the Nirex generic phased disposal concept. (authors)

[en] UK regulatory requirements require that the 'assessed radiological risk ... to a representative member of the potentially exposed group at greatest risk should be consistent with a risk target of 10^-6 per year' and that risks should be 'summed over all situations that could give rise to exposure to the group'. It is a further requirement that a repository performance assessment provides a 'comprehensive record of the judgements and assumptions on which the risk assessments are based'. In order to meet these requirements, Nirex, working with AEA Technology, has developed an approach to performance assessment based on the identification and analysis of features, events and processes (FEPs). The objectives of the approach are to provide a comprehensive, traceable and clear presentation of a performance assessment for a deep geological radioactive waste repository. The approach to scenario development is fundamental to the overall Nirex strategy for performance assessment, eventually leading to a repository safety case for regulatory submission. This paper outlines the main concepts of the approach, illustrated with examples of work undertaken by Nirex to demonstrate its practicality. Due to the current status of the Nirex repository programme, the approach has not yet been used to conduct a full performance assessment of a repository located at a specific site. (authors)

[en] The Department of Energy owns a number of nuclear materials that require physical protection. This protection is required for the materials in transit as well as in storage. The resource capacity for protecting these materials in transit was allowed to decline after the end of the cold war. As Records of Decision regarding the disposition of surplus special nuclear materials (SNM) are implemented, the Department's secure transportation workload will increase dramatically. New resources cannot be added fast enough to support the growth in work scope unless secure shipping operations become more efficient. This paper describes our effort to model integrated secure shipping operations and to recommend changes to shipping plans that reduce workload and increase capacity

[en] A study carried out by Mutadis and CEPN, on request of the CEA, aimed at supplying some elements allowing to elaborate some performance criteria for a long-term management system in front of situations of temporary abandonment of radioactive waste disposal facilities. The first part of the study has been the identification of case studies illustrating situations of loss of maintenance or temporary abandonment. The second phase has been the selection and analysis of 4 case studies (the ancient underground cavities in Ile-de-France, the regulation relative to new underground quarries, the abandoned mines in Loraine basin, and Unesco's approach for the protection of mankind world patrimony). These cases have been analysed with respect to various aspects: actors involved, construction management and memory preservation, liabilities in time and space, prevention means, scheduling, and resumption strategies. The concepts of abandonment, scheduling and resumption have been precised and analysed in a third part according to the case studies. Three goals - avoiding abandonment, encouraging scheduling and resumption - and eight characteristics are drawn from this analysis, which are indicators of the robustness of the system implemented to fulfill these 3 goals. These characteristics appear as strongly interdependent. (J.S.)