ABSTRACT
This introduction presents an overview of key concepts discussed in the subsequent chapters of this book. The book focus on disposal of slightly and moderately dangerous waste that the book defines as low-level radioactive wastes (LLWs) and intermediate-level radioactive wastes (ILWs). Waste with long-lived activity requires the construction of complex engineered barriers and elaborate sealing and stringent requirements for the waste treatment and packaging. For ILW and other radioactive waste with long-lived radioactivity but without producing heat, underground disposal is generally preferred or required by national laws. The book examines what underground that can be used with respect to compressibility, bearing capacity, and hydraulic conductivity. It employs soil and rock mechanics are the technical subjects. As is commonly done when dealing with the disposal of highly radioactive waste, one distinguishes primarily between crystalline rock, salt rock, argillaceous rock, and clastic clay. Salt consisting of halite (NaCl) or sylvite (KCl) is well defined and known for its creep behavior.
