Hitoshi Makino

Knowledge management for radioactive waste disposal: moving from theory to practice

The exponential growth in the knowledge base for radioactive waste management is a cause for concern in many national programmes. In Japan, this problem is exacerbated by a volunteering approach to siting of a deep geological repository, which requires particular flexibility in the tailoring of site characterisation plans, repository concepts and associated Performance Assessments (PAs). Recognition of this situation led, in 2005, to initiation by Japan Atomic Energy Agency (JAEA) of an ambitious project to develop an advanced Knowledge Management System (KMS) aimed to facilitate its role as the supplier of background R&D support to both regulators and implementers of geological disposal. The paper will review progress to date in this work, with emphasis on tailoring of existing Knowledge Engineering tools and methods to radioactive waste management requirements, and outline future developments and challenges.

A Challenge on Development of an Advanced Knowledge Management System (KMS) for Radioactive Waste Disposal: Moving from Theory to Practice

In recent years there has been much discussion on the topic of knowledge management in many areas of nuclear science, particularly associated with the nuclear renaissance and the evident shortage of skilled manpower (e.g. Yanev, 2008). More generally, however, the exponentially expanding capacity of computer systems parallels an explosion in the documentation and databases supporting nuclear projects. This is nowhere more evident than in the field of radioactive waste management, characterised, as it is, by the extremely wide range of disciplines involved and very long project timescales (e.g. Kawata et al., 2006; Umeki et al., 2008; Umeki et al., 2009). Although this may not yet be universally accepted, there is increasing evidence that the rapid rate of growth of material supporting complex technical projects – which we will term ‘knowledge’ – is rapidly reaching, if not passing, the point where conventional management systems show signs of collapse. Although tried and tested over millennia, the type of Knowledge Management System (KMS) developed to handle written documents is proving inherently incapable of being simply modified to cope with the present flood of electronic material. Although Moore’s Law of expansion of data transfer speeds and storage capacity means that some of the simpler tasks involving document collation and archiving can be handled, there has been little progress in addressing the more difficult problems of how the huge volumes of documentation being produced can be critically reviewed/quality assured, synthesised, integrated and communicated to all the interested stakeholders in a form that they can understand. A common blockage to progress is that, while many of the component problems (symptoms) may be acknowledged, it is not easy for organisations to perceive the magnitude of the approaching catastrophic system collapse and hence to implement the paradigm shift needed to introduce effective solutions. Indeed, it is a classic Catch-22 situation: the breakdown of conventional approaches means that those involved lack the overview required to see that their KMS is becoming increasingly dysfunctional. The exponential growth in the knowledge base for radioactive waste management is a cause for concern in many national programmes. In the Japanese radioactive waste disposal field,

Practical Application of the KMS: 1) Total System Performance Assessment

Comprehensive total system performance assessment (PA) is a key component of the safety case. Within this PA there are a number of tasks that reuse specific models and datasets, together with associated knowledge base for the disposal system considered. These are tasks where recent developments in the Knowledge Management System by Japan Atomic Energy Agency (JAEA KMS) can lead to optimisation of procedures. This paper will outline the reformulation of PA as a Knowledge Management (KM) task, discuss application of KM technologies to PA tasks, and illustrate how these can be handled electronically in a “Performance assessment All-In-one Report System (PAIRS)” utilising hyperlinks and embedded tools to minimise duplication of material, ease Quality Assurance (QA) and facilitate the regular updating required in the Japanese programme.Copyright

Development of Methodology of Groundwater Flow and Solute Transport Analysis in the Horonobe Area, Hokkaido, Japan

It is important for establishment of safety assessment techniques of geological disposal to understand groundwater flow and solute transport accurately. Therefore, we are positioning to confirm an applicability of the techniques in realistic environment as a crucial issue in R&D. We have attempted and planed some relevant studies as below: - A methodology to integrate activities from site investigations to evaluation of solute transport was examined. We have carried out groundwater flow analysis on a regional scale using geological and hydrological information from surface-based investigations at the Horonobe area, and also solute transport analysis based on the information of the trajectory analysis. - We have carried out a preliminary simulation of groundwater flow and salinity concentration distribution using information on climatic and sea-level changes, and evolution of geological structures considering the impacts of natural events and processes. Consequently, we could outline the impacts of natural events and processes on geological environment including hydrogeology, hydrochemistry and their evolutions. - We have been planning to develop and apply a methodology of groundwater flow and solute transport analysis to the shallow part, the Horonobe coastal area and around the URL. These techniques would become a basis for future site specific safety assessment in Japan.Copyright

Supporting Development of Practical Designs for a Japanese HLW Repository

In preparation for actual repository implementation, designs that could be tailored to specific sites need to be considered. This requires a paradigm shift in design philosophy, moving away from a single reference design towards a flexible and systematic “catalogue” of engineered barrier components and associated repository infrastructure. To support this development, novel methodology for both developing and comparing repository design options for Japanese vitrified high-level radioactive waste (HLW) has been examined. This paper will outline the background of the project and, in particular, some novel approaches examined for facilitating optimisation of practical repository designs. It is complemented by a companion paper - Matsumoto et al: Application of Formal Knowledge Engineering Approaches to Develop A Design Catalogue for A Japanese HLW Repository -, which describes the repository design process in more detail and illustrates results of first dry runs of the methodology.

Challenges for the JAEA KMS: Fostering Inventive Design and Problem Solving

The Knowledge Management System by Japan Atomic Energy Agency (JAEA KMS) is being developed to be flexible and able to respond to potential changes of boundary conditions. On a shorter timescale, the KMS must encourage flexibility in the methodology used for carrying out and presenting performance assessments. This is closely linked to development of advanced repository concepts; considering the requirements for a safe and practical repository tailored to specific site conditions, which reflects evolving technology. These coupled development tasks were, in the past, carried out by expert teams in a rather informal manner. As the technical challenges increase — and the need for transparency is accepted — a more formal method of developing innovative design solutions is needed. A knowledge engineering approach that is used in other financial and industrial applications has thus been tested for its usefulness for such tasks.Copyright