Chapters by a distinguished group of international authors on various aspects of Underground Injection Science and Technology are organized into seven sections addressing specific topics of interest. In the first section the chapters focus on the history of deep underground injection as well regulatory issues, future trends and risk analysis. The next section contains ten chapters dealing with well testing and hydrologic modeling. Section 3, consisting of five chapters, addresses various aspects of the chemical processes affecting the fate of the waste in the subsurface environment. Consideration is given here to reactions between the waste and the geologic medium, and reactions that take place within the waste stream itself. The remaining four sections deal with experience relating to injection of, respectively, liquid wastes, liquid radioactive wastes in Russia, slurried solids, and compressed carbon dioxide. Chapters in Section 4, cover a diverse range of other issues concerning the injection of liquid wastes including two that deal with induced seismicity. In Section 5, Russian scientists have contributed several chapters revealing their knowledge and experience of the deep injection disposal of high-level radioactive liquid processing waste. Section 6 consists of five chapters that cover the technology surrounding the injection disposal of waste slurries. Among the materials considered are drilling wastes, bone meal, and biosolids. Finally, four chapters in Section 7 deal with questions relating to carbon dioxide sequestration in deep sedimentary aquifers. This subject is particularly topical as nations grapple with the problem of controlling the buildup of carbon dioxide in the atmosphere.* Comprehensive coverage of the state of the art in underground injection science and technology* Emerging subsurface waste disposal technologies* International scope