January 1, 2001 / Volume 35 , Issue 1 / p. 39 A Copyright © 2001 American Chemical Society
Book Review Remediation in Rock Masses Edited by Hilary I. Inyang and Clifford J. Bruell American Society of Civil Engineers Press 1801 Alexander Bell Dr. Reston, VA 20191-4400 2000, 256 pp., $49
Remediation in Rock Masses is promoted as the only publication ". . . to fully present the problems and solutions to the complicated issue of contaminated rock site remediation". Perhaps true, but such a claim seems a bit pretentious. It should be used in conjunction with texts such as Bear, Tsang, and de Marsily's Flow and Contaminant Transport in Fractured Rock and the National Research Council's Rock Fractures and Fluid Flow: Contemporary Understanding and Applications. After a comprehensive introduction to rock mass remediation, the book delves into three main areas: modeling remedial actions in fractured-rock aquifers (this section is somewhat limited); site characterization—some innovative techniques; and remediation, which composes the bulk of the text. Chapter 1 lays out the difficulties of dealing with contaminated fractured-rock aquifers. Mathematics are present at a basic level. The next three chapters discuss aspects of solutetransport modeling in fractured-rock terrains. Chapter 2 provides a nice description of generally accepted modeling approaches, then moves on to a more in-depth discussion of the dual-porosity concept. The importance of the matrix is given due attention. Other factors, such as heterogeneity, thermal effects, and nonlinearity, are discussed in some detail. Chapter 3 is an in-depth discussion of the theory of solute mixing at fracture junctions. The authors avoid involved formula derivations and discuss complicated processes in a readable and understandable form. Chapter 4 completes the modeling discussion but is not for the faint-hearted. It discusses the theory of capture-zone delineation in a fractured-rock aquifer and should be recommended reading to anyone contemplating such an approach for contaminated rock masses. The topic of site characterization is included within chapters 5-9, which are a mixture of methods development and case histories. Chapters 5 and 6 discuss the interconnectivity of fractured-rock aquifers in the Triassic red beds and crystalline rocks, respectively. The discussion illustrates the need to address fractured-rock aquifers, in which there is extensive solute transport via horizontal fractures that are interconnected by vertical fractures. The value of good conceptual models with specific techniques are emphasized. Chapter 7 is an extremely detailed discussion of borehole wireline methods by the foremost practitioner in the field. It requires reader patience, but it is one of
wireline methods by the foremost practitioner in the field. It requires reader patience, but it is one of the better chapters. Case histories (Chapters 8 and 9) using basic hydrological approaches, complete this section. Chapter 9 is confusing to read: There's a page printing mixup. Remediation (Chapters 10-17) completes the book. Chapter 10 addresses solute transport through fractured-clayey till, but the concepts are relevant to transport in fractured-rock masses. Chapters 11 and 12 (case histories) and 17 consider pneumatic fracturing to enhance flow and solute recovery. Chapter 17 is a detailed discussion of the initial testing of the concept, according to standards of EPA's SITE program. In Chapter 11, the authors show that the pneumatic method apparently results in a relative flow improvement through the investigated fractures. Chapter 12 discusses enhanced pneumatic fracturing achieved by coupling the process with high-pressure fluid injection. Such bioaugmentation enables considerable bacteria dispersal and greater contaminants biodegradation than might otherwise have occurred. As a means for improving pump-and-treat systems (Chapter 15), hydrofracturing is deemed superior to pneumatic methods for propagating fractures, although no evidence is given. Chapters 14 and 16 are a little more specialized. Chapter 14 discusses in detail bentonite shaft seals for nuclear waste repositories to seal off chambers; Chapter 16 addresses alcohol flooding to enhance solute dissolution and physical mobilization. Both chapters lay out theories involved and practical aspects of the methods. This book is useful for field practitioners and graduate-level students but not greatly useful to theorists. It barely touches on the complexity of the field and some innovations being developed even as this review is being written, nor does it discuss aspects of fractured-rock masses in which permeabilities are enhanced through dissolution processes (e.g., karstic formations). This is perhaps for the best—it is generally inappropriate to lump karstic formations with nonkarstic fractured-rock formations due to their relative extreme differences. Reviewed by Malcolm S. Field, U.S. Environmental Protection Agency, National Center for Environmental Assessment
