A major part of this book is based on work performed by several of the national organizations that are responsible for disposal of radioactive waste from nuclear reactors, with the Author involved in the research as well in the reporting. He is greatly indebted to the organizations and to their representatives that were engaged in the projects, and to the European Commission, represented by Mr Christophe Davies, that supported the work ?nancially and otherwise. Mr Davies' services are gratefully acknowledged. The author also expresses his thanks to the following p- sons who assisted in various ways in the preparation of the book: Christer S- mar, Swedish Nuclear Fuel and Waste Management Co (SKB), Sweden; Wolf S- dler, Agence National pour la gestion des Dechets Radioactifs (ANDRA), France; Jan Verstricht, Studiecentrum voor Kernenergie-Centre d'Etude de l'ener ' gie Nuc- are (SCK-CEN), Belgium; and Tilmann Rothfuchs, Gesellschaft fur .. Anlagen- und Reaktorsicherheit GmbH (GRS), Germany. Lund, January 2008 Roland Pusch v Acknowledgment The author expresses his thanks to the following persons who assisted in va- ous ways in the preparation of the book: Christer Svemar, Swedish Nuclear Fuel and Waste Management Co (SKB), Sweden; Wolf Seidler, Agence National pour la gestion des Dechets Radioactifs (ANDRA), France, and Tilmann Rothfuchs, Gesellschaft fur .. Anlagen- und Reaktorsicherheit GmbH (GRS), Germany. vii Contents Introduction...1 National and International Work ...1 Basic Principle of Final Storage of Hazardous Waste ...2 TheCROPProject ...3 Crystalline Rock...5 SaltRock...5 Argillaceous Rock and Clastic Clay...