Disposal of Hazardous Waste in Underground Mines.
Edited by V. Popov and R. Push The Sustainable World, Vo/11 WIT Press, 2006 ISBN 1-85312-750-7 US $170.00, hardcover, 288p.
This book contains a collection of articles aimed at presenting the current experience in the utilization of underground mines for the safe storage of hazardous waste and forecasts future developments related to this topic. This collection is based upon the results of an international collaborative research project sponsored by the European Commission. The articles are assembled in a coherent manner, so that all the main aspects are covered. The content of the book partially duplicates other environmental collections, particularly those related to the safe disposal of low-level radioactive wastes. However, this book is not a repetition of previously published materials because the editors made sure that other hazardous wastes, such as alkaline batteries, pesticides, consumer goods and products containing dioxins, furans, etc., are included. More importantly, the economic and legal aspects of waste disposal are treated in a comprehensive manner, so legislators, businessmen or environmentalists willing to acquire a practical knowledge of the subject can use parts of this book to their advantage.
The book has 6 chapters and an appendix spread over 260 pages. The first chapter examines hazardous waste generation and management in Europe. Statistical data are shown about the amount of waste generated per person, the main waste streams and emission trends, and expectations up to the year 2010. At the end of the chapter a brief but informative overview regarding the wastes of concern, such as heavy metals and persistent organic pollutants, is presented.
The second chapter reviews the need and potential for underground disposal and provides an overview of underground mines in Europe. This chapter is helpful for a general reader, because it presents the fundamentals of the problem and discusses the two principal standing points of this technology, namely the availability of underground storage space in industrialized countries and the advantages of underground disposal compared to surface disposal.
The third chapter reviews the criteria for selecting repository mines. Different scenarios are analyzed such as mines in crystalline rocks, argillaceous rocks, salt rocks and other rock types. The favourable and unfavourable conditions dictated by the rock structure, hydrology and stress conditions are presented in a concise way. Although the significance of rock properties is discussed in more detail in the next chapters, the empirically deduced criteria and sound sense presented in this chapter should be sufficient for non-academic readers to grasp the basic principles of site assessment.
The fourth chapter deals with engineering barriers most commonly used in underground mines. The emphasis is on the application of clay materials for isolation, because of the cost effectiveness and good isolation properties of clays. The basic manipulations and processing of clays are discussed using as an example two brands of clay, namely MX-80 and Friedland Ton. Properties of the clays such as rate of hydration, chemical interactions between smectite and cement, and conversion of the smectite to nonexpandable minerals (illitization) are examined quantitatively. At the end of the chapter, important remarks about the cost of disposal of given amounts of batteries and pesticides are given.
The fifth chapter is devoted to the mechanical integrity of the mines. The rock mechanic properties are discussed with respect to the Coulomb failure criterion. The suggestions for modelling of stress conditions offered in this chapter are illustrated with 3D diagrams from particular mines. The modelling is based on the boundary-element method and it is applied using specially customized software (GiD, [http://gid.cimne.ups.es]). The nature of the customization and the principles of the calculation methodology are not discussed in detail. In general, the treatment of the problems in this chapter is rather brief, and some important details regarding the connection of the model to a particular geological environment are missing, as well as the theoretical justification for choosing a particular model. In other words, although the models described in this chapter may be of significant value, it is unlikely that the reader can use them unless he or she is a specialist in this subject.
The sixth chapter is the longest (pp. 151-207) and theoretically most complex, because it deals with risk assessment of underground repositories using numerical modelling of flow and transport in porous and fractured rocks. The chapter begins with an overview of the theoretical problem, with emphasis on the differences in approach to modelling for the nearfield and far-field zones around underground openings. Next, the governing equations for flow in porous and fractured rock media are discussed, which are needed for the development of flow models. This is followed by general discussion of the boundary-element method. In the second half of this chapter, the models are applied to particular tunnel geometries for migrants such as dichlorvos and zinc.
The appendix contains a list of inactive and active mines in Belgium, Denmark, Finland, France, Greece, Ireland, Italy, Luxemburg, Portugal, Spain, Sweden, Nederland and the United Kingdom. The list provides data about the mine operator and the annual mine capacity in cubic tonnes of mined material.
In general, the first three chapters of the book contain a variety of data that can be used by non-specialists to acquaint themselves with the problems associated with underground storage of hazardous wastes. The last chapters treat stress and flow models and are relevant to qualified engineers who have previous experience in hydraulics calculations and applications of numerical models. The book is richly illustrated but some of the illustrations are detached from their context in the book. Little is said about data collection procedures and the availability of data needed for building the numerical models. My personal opinion is that this book contains a good introduction to the procedures and practices of hazardous waste storage but it is most suitable for qualified geoengineers rather than students.
Reviewed by Ivan Dimitrov
University of New Brunswick
2 Bailey Drive
Fredericton, NB, E3B 5A3, Canada