The Importance of Verification and Validation Testing of Engineering Designs in Underground Rock Laboratories
- PDF / 211,535 Bytes
- 6 Pages / 432 x 648 pts Page_size
- 0 Downloads / 155 Views
The Importance of Verification and Validation Testing of Engineering Designs in Underground Rock Laboratories Eleanor M. Scourse1, Wolfgang Kickmaier1, Ian G. McKinley1, Hideki Kawamura2 and Samuel T. Stephens3 1 MCM, Baden, Switzerland 2 Obayashi, Tokyo, Japan 3 Atkins, Bristol, UK ABSTRACT Several national programs for geological disposal of higher activity radioactive waste will initiate siting via a call for volunteers. This is probably furthest advanced in Japan (NUMO) and the UK (NDA RWMD). In both these cases, rather than focusing on a reference repository concept, a catalogue of options has been developed. This requires a process to tailor design options to sites and compare particular design/site combinations as part of the site selection process. As has been noted in the longer-running Japanese program, the assessment of options must be as realistic as possible, rather than conservative, as in past nominating approaches to siting. Past demonstration work has focused on feasibility, showing that it is possible to implement a design. Determining practicality, which incorporates many more complex factors, is more difficult. Extensive desk studies can form a basis for such analysis but these must be rigorously tested, which makes full-scale tests in Underground Rock Laboratories (URLs) an essential component of any program. This paper highlights the importance of such demonstration projects and illustrates how they are vital in both improving understanding of the engineered barrier system and stakeholder engagement. Key words: Higher activity waste, Repository design, Concept testing, URL, Volunteer siting INTRODUCTION Many countries are investigating implementation of geological disposal facilities for radioactive waste arising from nuclear power generation, research, medicine, and industry. Recently, some countries have initiated siting by inviting interested communities to volunteer to host a geological disposal facility. Examples of countries that are particularly advanced in this process are Japan [1] and the UK [2]. Although the technical basis for disposing of all radioactive waste is fundamentally similar, here we focus on vitrified high level waste and spent fuel. By adopting a voluntary approach, the geological environment cannot be identified in advance. Therefore all potentially acceptable geological environments must be considered if they arise in the volunteer process. This means that, rather than focusing on a reference repository concept, a catalogue of potential options is developed to allow designs to be flexible and tailored to the characteristics of a volunteer site. An outline of the catalogue of concepts currently considered by the UK and Japan can be found in the report NUMO 2004 or NDA RWMD 2010. This approach requires a process to tailor design options to sites and to compare various design/site combinations as part of the site selection process. As discussed extensively by NUMO, the assessment of options cannot be based on the conservative approach used for previous feasibility studie
Data Loading...
