The long-term stability of groundwater conditions at repository sites : proceedings of the PADAMOT workshop, Brussels 2002

A workshop was held at the Hotel Carrefour de la Europe in Brussels on 2nd & 3rd October 2002 as part of the project 'Palaeohydrogeological Data Analysis and Model Testing' (PADAMOT), being undertaken in the EC/Euratom 5th Framework RTD programme in nuclear fission safety. PADAMOT continues the research directions that were started in the 4th Framework EQUIP project ('Evidence from Quaternary Infills for Palaeohydrogeology'). In addition, it will develop improved methods and recommendations for linking these data with the requirements for long-term safety assessments. This volume of Proceedings records the workshop presentations and the questions, answers and comments raised in subsequent discussion. The first set of presentations documented here provide overviews of past EC projects on palaeohydrogeology, namely the EQUIP, PHYMOL and PAGEPA projects (the ‘PALHY’ cluster in the 4th Framework Programme) and a related 4th Framework Programme investigation of the Palmottu site in Finland. In addition to these summary papers an introduction to the PADAMOT project itself is provided as is a brief synopsis of the potential use of novel analytical techniques for future palaeohydrogeological studies. .A key part of the workshop was the involvement of independent expert ‘facilitators’ to synthesise issues. Two papers are included here relating to the value and use of palaeohydrogeological information in past repository safety assessments. Finally, this report documents the summaries of the working group and plenary discussions that were led by the independent experts, addressing the questions: • How do hydrochemical & mineralogical data support confidence in deep repository stability? • How can that knowledge be applied more effectively in future safety cases?