The management and disposal of radioactive wastes are key international issues requiring a sound, fundamental scientific basis to insure public and environmental protection. Large quantities of existing nuclear waste must be treated to encapsulate the radioactivity in a form suitable for disposal. The treatment of this waste, due to its extreme diversity, presents tremendous engineering and scientific challenges. Geologic isolation of transuranic waste is the approach currently proposed by all nuclear countries for its final disposal. To be successful in this endeavor, it is necessary to understand the behavior of plutonium and the other actinides in relevant environmental media. Conceptual models for stored high level waste and waste repository systems present many sCientific difficulties due to their complexity and non-ideality. For example, much of the high level nuclear waste in the US is stored as alkaline concentrated electrolyte materials, where the chemistry of the actinides under such conditions is not well understood. This lack of understanding limits the successful separation and treatment of these wastes. Also, countries such as the US and Germany plan to dispose of actinide bearing wastes in geologic salt deposits. In this case, understanding the speciation and transport properties of actinides in brines is critical for confidence in repository performance and risk assessment activities. Many deep groundwaters underlying existing contaminated sites are also high in ionic strength. Until recently, the scientific basis for describing actinide chemistry in such systems was extremely limited."

Anoxic basins are ofgreat interest to oceanographersofall disciplines. Theirextreme conditionsresult from acombinationofhigh oxygen utilization and restricted circulation. It is necessery to understand present -day anoxic environments ifwe are to understand the early evolution of the oceans (e.g. SiIlen, 1965). Sarmiento et al.(1988a) explored the causes of anoxia in the global ocean, which is in effect a "closed" basin and in marginal seas such as the Eastern Mediterranean (Sarmiento et al. 1988b). Anoxic conditions have been proposed toexist in various ocean basins at different times in the geological past (e.g. the Crataceous period; Weissert, 1981) and possibly as recent as the last glacial maximum (e.g., Sarmiento and Toggweiler,1984). The modern Black Sea has been considered as the type anoxic basin. It is the world's 2 3 largest permanaently anoxic basin (area = 423,000 km; volume = 534,000 km ) and is thought to be aquasi-steady state system. It is extremely isolated from the rest ofthe world's oceans. Only the narrow and shallow Bosporus Strait provides water exchange with the Mediterranean. Concentrationsofhydrogen sulfide reach valuesof350 Mm in the deep water and the oxygen-hydrogen sulfide Interface exists between 80 and 200m waterdepth. The hydrographic regime is characterized by low salinity surface water of riverine origin overlying high salinity deep waterofMediterranean origin. Asteep pycnocline is the primary phycical barrier to mixing and is the origin of the stability of the anoxic interface.

This Special Issue of Water, Air and Soil Pollution offers original contributions from BIOGEOMON, an international symposium on ecosystem behavior and the evaluation of integrated monitoring of small catchments, held in Prague, Czech Republic, in September 1993. The meeting attracted nearly 200 scientists from 27 countries on five continents. BIOGEOMON was a loose continuation of another international meeting, GEOMON, which was held in Prague in 1987. Both sym posia provided a forum for the discussion of ideas on environmental problems in western and eastern Europe, with important contributions from the American continent. With the dramatic collapse of the iron curtain, it was our hope that more so than GEOMON, BIOGEOMON would provide opportunities for the free exchange of ideas, fostering the development of research collaborations between its participants. With international openness comes the increasing realization that every indus trialized nation has its own legacy of environmental degradation. Anthropogenic impacts differ in severity and scale; air and water transport of pollutants transform local impacts into regional and global ones, ignoring political boundaries and eco nomic differences. Environmental consequences of anthropogenic activities often are detectable at the ecosystem level. Thus, the challenge of ecosystem science, and to the individuals who practice it, is to develop a comprehensive understanding of ecosystem function in the past and at present, and to apply such understanding toward minimizing future insults to the local, regional, and global environment.

The workshop "From Dust to Terrestrial Planets" was initiated by a working group of planetary scientists invited to ISSI by Johannes Geiss in November 1997. The group split to focus on three topics, one of which was the history of the early solar system, including the formation of the terrestrial planets in the inner solar system. Willy Benz, Gunter Lugmair, and Frank Podosek were invited to convene planetary scientists, astrophysicists, and cosmochemists to synthesize the current knowledge on the origin and evolution of our inner planetary system. The convenors raised the interest of scientists from all over the world in the detailed assessment of the available astronomical, chronological, geochemical and dynamical constraints of the first period of inner solar system evolution. In partic ular, this included appraisal of the newest results from astronomical observations by the Hubble Space Telescope, the Infrared Space Observatory, and other space and ground-based facilities of solar-like systems and nebular disks, possibly repre senting early stages of the solar accretion disk and planet formation. At the same time, the current models of the origin, evolution, transport, and accretion processes of circum stellar disks were presented. This included the new insights provided by the recent discovery of extrasolar giant planets, which were considered insofar as they are relevant to the overall dynamics of the inner part of the solar system.

Here is a collection of papers from BIOGEOMON, The Fourth International Symposium on Ecosystem Behavior. The contributions address a wider-than-ever range of concerns: aspects of catchment monitoring and modeling; nitrogen transformations and processes; stable and radiogenic isotopes; biogeochemistry of restored ecosystems; and the dynamics of such chemicals as mercury and phosphorous, among many other topics.

Brominated flame retardants are one of the last classes of halogenated compounds that are still being produced worldwide and used in large quantities in many applications. They are used in plastics, textiles, electronic circuitry, and other materials to prevent fires. This volume covers the state-of-the-art of the analysis, fate and behaviour of brominated flame retardants. Experts in the field provide an overview of the compounds physico-chemical properties and uses, their occurrence in the environment and biota, advanced chemical analytical methods, degradation studies, toxicological effects and human exposure. This book is a valuable and comprehensive source of information for environmental scientists interested in brominated flame retardant issues, and for authorities and producers."

Solid-solution equilibria of marine evaporites are important in a wide range of science and technology. However, the data had not yet been summarized in a form that is at the same time comprehensive and permits to understand how the quinary seawater system builds up from its bounding systems. Thus the goal of the present volume is at the same time scientific and educational. The understanding of solid-solution equilibria of the various systems with respect to dissolution, precipitation and transformation of solids, their application to the evolution of brines, and a fast access to data is a necessary requirement for any modelling, especially in Geoscience. Another goal is to show the avail ability of data. Unfortunately, though solubility data are numereous there are substantial gaps, especially with respect to high temperatures. But also up to about 100 0 C data are missing for some of the systems so that they cannot be described entirely. Based on the present volume further work on the solubili ties of the minerals of marine evaporites may be promoted. The data have been viewed and collected over several years by the first author. The second author entered the preparation of the volume when it was realized that besides graphics and tables a fast access to data was required. Although both authors are responsible for the whole volume, responsibility is weighted somewhat differently for the various parts."

Water scarcity affects hydrologic resources, systems connectivity, biodiversity, water quality, and river ecosystem functioning. It has direct impacts on economic sectors that use and depend on water, such as agriculture, tourism, industry, energy and transport. The Mediterranean Basin is one of the regions in the world most vulnerable to climate changes, as well as one of the most impacted by human water demand. This volume provides an in-depth view of the water quality and quantity implications of water scarcity. It highlights its possible causes and describes the effects in regions under Mediterranean climate. The topics covered include climate effects, water resources (use, storage and new sources), water quality (chemical and microbiological), and the effects on ecosystems suffering from water scarcity. This book is addressed to scientists and students, but also to managers involved in the necessary decision making process to face future periods of drought.

Most of the world s mountains are rich in water and, as such, play a pivotal role in the global water cycle. They provide water for diverse human uses and ecosystems. Growing water demands as well as climate change will lead to ever-increasing pressure on mountain waters. Overcoming water-use conflicts and maintaining the ecological functioning of mountain waters presents a highly challenging task and is indispensable for sustainable development.
This book extensively portrays the highly diverse attributes of mountain waters and demonstrates their paramount importance for ecological and societal development. The extensive summaries on the scientific basics of mountain waters are supplemented with considerations on the diverse water uses, needs for management actions, and challenges regarding sustainable water management. This overview concerns not only the mountain areas themselves but also downriver reaches and their surrounding lowlands, and, therefore, the relationship between mountain and lowland water issues."

Within very recent time, when investigating the allowing one to explain possible transformations according to variations in different characteristics physicochemical conditions under which sedimen tary rocks formed, geologists were satisfied with of the environment. logical premises prompted by sound judgment. The present book is written within the indicat ed framework. I am pleased that this book, in which Recognizing the great role of this factor in develop ment of the science, it is still necessary to keep in the graphical method is used and popularized, has mind that sound judgment based on impressions and been translated into English. subjective experience of the observer does not al In giving a physicochemical evaluation of ways bring us to an understanding of objective existing methods for determining the oxidation reduction conditions under which sedimentary rocks reality. Probably greater success in explaining the form, I have tried to present the material in such a way that the warning against too formal an applica physicochemical features of the environment in which sediments accumulate may be achieved by tion of thermodynamics is obvious."

The past two or three decades have seen many important advances in our knowledge of the chemistry, physics, geology and biology of the oceans. It has also become apparent that in order to understand the manner in which the oceans work as a 'chemical system', it is necessary to use a framework which takes account of these interdisciplinary advances. Marine geochemistry has been written in response to the need for a single state-of-the-art text that addresses the subject of treating the sea water, sediment and rock reservoirs as a unified system. In taking this approach, a process-orientated framework has been adopted in which the emphasis is placed on identifying key processes operating within the 'unified ocean'. In doing this, particular attention has been paid to making the text accessible to students from all disciplines in such a way that future advances can readily be understood. I would like to express my thanks to those people who have helped with the writing of this volume. In particular, I wish to put on record my sincere appreciation of extremely helpful suggestions made by Professor John Edmond, FRS. In addition, I thank Dr S. Rowlatt for his comments on the sections covering the geochemistry of oceanic sediments, and Dr G. Wolff for his invaluable advice on the organic geochemistry of biota, water and sediments. It is a great pleasure to acknowledge the help of Dr K. J. T.

Azo dyes play an important role as coloring agents in the textile, food, and pharmaceutical industry. Due to the toxicity, mutagenicity and carcinogenicity of azo dyes and their breakdown products, their removal from industrial wastewaters has been an urgent challenge. Promising and cost-effective methods are based on their biodegradation, which is treated in this volume. The topics presented by experts in the field include: the classification of azo dyes; toxicity caused by azo dyes; aerobic and anaerobic azo dye biodegradation mechanisms; the role of bacteria, fungi, algae and their enzymes in biodegradation; the impact of redox mediators on azo dye reduction; the integration of biological with physical and chemical processes; the biotransformation of aromatic amines; reactor modelling for azo dye conversion; the biodegradation of azo dyes by immobilized bacteria and fungi; and factors affecting the complete mineralization of azo dyes.

This book is a collection of all the lectures by the professors attending the 3rd "Interna tional School on Marine Chemistry" held in Ustica (Palermo, Italy, September 2000), under the auspices of the United Nations and the Italian Chemical Society. The School was organized by the University of Palermo in co-operation with the Natural Marine Reserve of Ustica Island. The Organising Committee of the School wishes to thank the University of Messina, the University of Roma "La Sapienza: ' the Italian University Consortium of Environ mental Chemistry, and the Marine Reserve of Ustica Island for their financial support to the School. This book has been printed with the financial support of the Environmental Re search Centre CIRITA of the University of Palermo. thank all the professors whose outstanding scientific contributions have The editors made it possible to publish this book. Professor Antonio Gianguzza Professor Ezio Pelizzetti Professor Silvio Sammartano Contents Part I Biogeochemical Processes at the Air-Water and Water-Sediment Interface .............................................. ."

This book is for undergraduates, postgraduates and research workers who wish to gain an insight into present ideas and speculations on the origin of granite batholiths. It is a summary of the proceedings of a one-day meeting of the Geochemistry Group of the Mineralogical Society held at the University of liverpool on the 2nd May 1979, entitled The Origin of Granite Batholiths: Geochemical Evidence. It was felt that relevant new geochemical and isotopic data with associated field and petrological observations would be helpful in clarifying the main issues connected with the origin of granitic rocks. The speakers who participated contri buted a wealth of data and ideas to the problem, based on many years' experience of granitic rocks in various parts of the world. The popularity of the meeting indicated that a summary of the talks might be welcomed by a wider audience; hence this book. For reasons of length and cost, authors have been limited to presenting only the essential results necessary to develop their arguments and ideas. The comprehensive reference list will, however, assist those who wish to pursue specific aspects in greater detail. Inevitably, the cost and speed of publication may have resulted in some errors and inconsistencies which would not have occurred in a book produced over a longer time-span, but the editors hope that the rapid and up-to-date publication will offset this. The controversy over the origin of granite is as old as the science of geology."

Following release to the environment, synthetic chemicals may be degraded by biotic and abiotic processes. The degradation of the chemical can follow a plethora of pathways and a range of other substances can be formed via thesedifferentpathways(e.g.[1]).Anumberoftermshavebeenusedforthese substances including metabolites, degradates and transformation products - in this book we use the term transformation products. While we often know a lot about the environmental properties and effects of the parent synthetic chemical, we know much less about the transformationproducts. Transformationproductscanbehave very differently fromtheparent c- pound (e.g. [2]). For example, selected transformation products are much more persistent than their associated parent compound in soils, waters and sediments andsomemaybetransported aroundthelocal,regionalandglobal environmentstoadifferentextentthantheparentcompound.Transformation products can also have very different toxicities than the parent compound (e.g. [3]) and in some cases transformation products can be orders of mag- tude more toxic than their parent compound; although this situation is rare. The environmental risks of transformation products can therefore be very different than the risks of the parent compound. Thepotentialenvironmentalimpactsoftransformationproductsarerec- nised by many regulatory assessment schemes. For example, in the EU, pes- cideproducersarenotonlyrequiredtoassessthefateandeffectsoftheparent pesticide but are also required to assess the potential adverse effects of major metabolitesandminor metabolitesthat aredeemed tobeofconcern[4]. S- ilar requirements also exist for new human and veterinary pharmaceuticals and biocides (e.g. [5]). However, for many older substances and many other substance classes (e.g. industrial chemicals), data on the environmental risks of transformationproductscan be limited or non-existent.

This series of monographs represents continuation on an international basis of the previous series MINERALOGIE UNO PETROGRAPHIE IN EINZELOARSTELLUNGEN, published by Springer-Verlag. The voluminous results arising from recent progress in pure and applied re search increase the need for authoritative reviews but the standard scientific journals are unable to provide the space for them. By their very nature, text-books are unable to consider specific topics in depth and recent research met'hods and results often receive only cursory treat ment. Advanced reference volumes are usually too detailed except for experts in the field. It is often very expensive to purchase a symposium volume or an "Advances in . . . " volume for the sake of a specific review chapter surrounded by unrelated chapters. We hope that this monograph series will by-pass these problems in fulfilling the need. The purpose of the series is to publish, at reasonable prices, reviews and reports of care fully selected topics written by carefully selected authors, who are both good writers and experts in their scientific field. In general, the mono graphs will be concerned with the most recent research methods and results. The editors hope that the monographs will serve several functions, acting as supplements to existing text-books, guiding research workers, and providing the basis for advanced seminars. August 1967 W. VON ENGELHARDT, Tiibingen T. HAHN, Aachen R. Roy, University Park, Pa. J. W. WINCHESTER, Ann Arbor, Mich. P. J. WYLLIE, Chicago, Ill."

Geochemistry is concerned with the laws governing the distribution of the chemical elements and their isotopes throughout the Earth. As a concept it has been recognized for 130 years but it has grown into a separate Earth science during this century. Geochemistry has mutual links with many neighbouring disciplines. Its present field of activity is determined by many problems of broad interest and by the availability of methods. Several exterior influences have recently developed. Thus, nuclear physics and its specific measuring techniques made isotope geochem istry possible, while space research has stimulated the development of cosmochem istry. Except a few "standard" materials as Gland W 1 there is no other rock on earth whose composition is as well known as that of meteorites colliding with our planet on their cosmic course. Biochemistry is linked with the rapidly developing new branch of organic geochemistry. Our discipline has moved forward in step with the advancement of analytical chemistry. When optical and X-ray spectrochemical analysis came into use and with the discovery of natural and artificial radio-activity, many new elements were identified. With the development of spectrophotometers, radiation counters and nuclear sources over the last 20 years, a flood of analytical data on geological sub jects has been released, and we ought to make use of it."

Destructive plate margin magmagenesis is one of the most intensely studied and widely debated topics in the earth sciences at present. Calc-alkaline volcanic and plutonic rocks in orogenic settings exhibit such a diversity of composition and character that the subducted oceanic lithosphere, the overlying 'enriched' lithospheric mantle and the lower continental crust all have been advocated recently as the primary source region for island-arc and continental-margin basaltic to andesitic magmas. The role of the upper continental crust is also a matter of continuing controversy. It is clear that crustal contamination is a common, but not universal, feature of destructive plate margin magmatism. Whether this contamination is introduced at source by subduction-related processes or occurs during magma transit by bulk anatexis and magma mixing, selective contamination or coupled fractional crystallization-assimilation mechanisms is central to most current discussions of andesite petrogenesis. This book presents a series of papers which directly address these and other important geological and geochemical problems within the context of the Mesozoic-Cenozoic calc-alkaline magmatism characteristic of the Andean Cordillera of western South America. Although it is aimed primarily at postgraduate students and researchers familiar with the Andes, it is also a useful general reference for workers in other fields who wish to gain an insight into current thoughts, ideas and speculations on 'andesitic' magmatism at destructive plate margins.

This is a book about the why and how of doing experiments on rocks, minerals, magmas, and fluids. It could have as logically been subtitled "Experimental petrology" as "Experimental geochemistry," but we chose geochemistry to emphasize the broad and overlapping nature of current experimental work. We have tried to aim the book at a general readership which we hope will include advanced undergraduate students, graduate students, and anyone else interested in learning something about experimental petrology. Although we hope there will be something of interest for the practicing experimentalist, our aim is at the non-experimentalist interested in learning why experiments are useful, what kind of experiments can be done, and what some of the major problems and limitations are and how they can best be avoided. The result of a journey through this book should be an ability to evaluate published experimental work critically and a knowledge of the kinds of problems an experimentalist might be able to help solve. Some details of experimental technique are included in the Appendix for those readers who want to "get their hands dirty. " Indeed, one of our main incentives for writing this book was to try to encourage more petrologists and geochemists to become experimentalists. In our pedagogical approach we have chosen to discuss a small number of case histories as illustrations of principles and techniques. We have tried to select studies we regard as well executed.

Every year Earth is bombarded with about 40,000 tons of extraterrestrial material. This includes microscopic cosmic dust particles shed by comets and asteroids in outer space, meteorites, as well as large comets and asteroids that have led to catastrophic events in the geologic past. Originally considered only a curiosity, extraterrestrial matter found on Earth provides the only samples we have from comets, asteroids and other planets. Only recently mankind has started to actively collect extraterrestrial matter in space (Apollo program, Stardust mission) rather than to wait for its delivery to Earth. Still, most of our knowledge of the origin and evolution of our solar system is based on careful studies of meteorites, cosmic dust, and traces of large impact events in the geologic record such as the mass extinction that terminated the Cretaceous Period and led to the extinction of the dinosaurs. This book summarizes our current knowledge of the properties, origin, orbital evolution and accretion mechanism of extraterrestrial matter accreted on Earth and sheds light on accretion processes and fluxes in the geologic past. The chapters in the first part of the book are arranged in order to follow extraterrestrial matter from its origin in space, its orbital evolution on its way to Earth, its interaction with the Earth magnetosphere and atmosphere to its more or less violent collision with the Earth's surface. In the second part of the book several chapters deal with the present?day flux of cosmic dust and meteorites to Earth. Finally, several chapters deal with the reconstruction of the accretion history of extraterrestrial matter on Earth, starting with the most recent geologic past and ending with the very early, violent accretion period shortly after the formation of Earth, Moon and other solid planets in our solar system.

The Thirteenth International Conference on Basement Tectonics was held on the campus of Virginia Polytechnic Institute and State University in Blacksburg, Virginia from June 2 -6, 1997. The oral presentations and discussions over three days covered a wide range of topics, and provided the international audience with a perspective on scientific efforts underway around the world. The conference participants were able to attend two separate field trips: (I) a pre-conference trip guided by Professor Robert Hatcher of the University of Tennessee, Knoxville, examined the Basement rocks in the North Carolina -Tennessee region of the Appalachian Mountains, and (2) a mid-conference field trip guided by A.K. Sinha, convener of the conference, allowed participants to examine the complex rock associations and structures of the> 1000 m.y. old basement rocks in Virginia. Both the field trip guidebooks and abstract volumes were published for the conference. The meeting brought together scientists from more than 14 countries. Their participation, and the fiscal success of the meeting would not have been possible without the support of the Department of Geological Sciences, the College of Arts and Sciences (VPI&SU) and the Basement Tectonics Association. Their support is gratefully acknowledged. As Chairman of the Organizing Committee, I would like to thank Margie Sentelle, Jay Thomas, Peter Welch, and Barry Robinson for the smooth operation of the conference.

Here is a comprehensive and up-to date compendium of the technology and management of MTBE contamination, exploring the myths which impede successful clean-up techniques, and offering effective solutions. Section I looks at the history, properties, occurrence and assessment of MTBE. Section II discusses applicable remediation technologies. Section III offers remediation case studies.

Acknowledgements Conference Summary R. D. EVANS, A. PROVINI, J. S. MATIICE, B. T. HART and J. WISNIEWSKI/Interactions Between Sediments and Water: Summary of the 7th International Symposium 1-7 Sediment I Water Dynamics D. E. WALLING and W. HE /Investigating Spatial Patterns of Overbank Sedimentation on River Floodplains 9-20 R. JEPSEN, J. ROBERTS and W. LICK / Effects of Bulk Density on Sediment Erosion Rates 21-31 T. G. MILLIGAN and D. H. LORING / The Effect of Flocculation on the Size Distributions of Bottom Sediment in Coastal Inlets: Implications for Contaminant Transport 33-42 loG. DROPPO, G. G. LEPPARD, D. T. FLANNIGAN and S. N. LlSS / The Freshwater Floc: A Functional Relationship of Water and Organic and Inorganic Floc Constituents Affecting Suspended Sediment Properties 43-53 C. H. TSAI and J. Q. HU / Flocculation of Particles by Fluid Shear in Buffered Suspensions 55-62 P. M. STONE and D. E. WALLING / Particle Size Selectivity Considerations in Suspended Sediment Budget Investigations 63-70 Q. HE and D. E. WALLING / Spatial Variability of the Particle Size Composition of Overbank Floodplain Deposits 71-80 C. YEN and Y. LIN KEY / Variations of Bed Surface Sediment Size in a Channel Bend 81-88 M. STONE and B. G. KRISHNAPPAN / Transport Characteristics of Tile-Drain Sediments From an Agricultural Watershed 89-103 U. KERN and B. WESTRICH / Sediment Budget Analysis for River Reservoirs 105-112 A. I. PACKMAN, N. H. BROOKS and J. J.

The Society of Environmental Geochemistry and Health (SEGH) Second International Conference on Arsenic Exposure and Health Effects was held June 12-14, 1995 in San Diego, California. The conference was at tended by 152 people who heard 41 presentations on all aspects of arsenic research. The speakers represented 14 countries. Approximately 40 of the participants and speakers were from countries other than the US. The participants represented government, academia, industry and the interested public. The sponsorship ofthe conference is a good indicationofthe wide spread interest in the subject and the meeting. The sponsors, in addition to SEGH, were the US Environmental Protection Agency (US EPA), the Agency for Toxic Substances and Disease Registry (ATSDR), the Atlantic Richfield Company (ARCO), the Electric Power Research Institute (EPRI), the American Water Works Association Research Foundation (AWWARF), Kennecott Corporation, the American Smelting and Refining Company (ASARCO), and the International Council on Metals in the Environment (ICME). The funding was split approximately equally between industry (including industrial organizations such as EPRI) and government. In addition to the many fine presentations, the meeting provided a forum for scientists from different countries to compare experiences and share information. It also provided a forum for the discussion of both scientific and policy issues between representatives of various governmental bodies (at the local, state, and federal level) and representatives of various indus trial organizations. These discussions occurred both in the formal meetings and informal settings during the meeting."