Following the end of World War II there was a major migra tion of population in the United States and Scandinavian countries to urban areas. As a result of this migration and in part due to the public works moratoria imposed during the war, a major pro gram of sewer construction was instigated, which resulted in the collection and subsequent concentration of large volumes of waste water at single discharge points. As the assimilative capacity of these receiving waters was exceeded, it led to or aggravated existing water pollution problems in these waters. To mitigate this degradation of water quality a massive program to construct wastewater treatment facilities was instigated. In addition, large amounts of money were spent on research to improve the technology of the conventional collection and treatment concept. In contrast, the wastewater disposal problem of the rural home owner received little attention, and in most cases the septic tank soil absorption system (ST-SAS) was the interim solution. In recent years there has been a fundamental change in the population growth pattern in the US and Scandinavian countries. It appears that a great many people are moving back to rural areas where they seem to prefer the suburban or small town envi ronment, yet at the same time want all the conveniences of urban life. The provision of proper wastewater disposal facilities presents a very perplexing problem, because the capital and operating costs of conventional sewers are usually financially impractical for rural areas.

The purpose of this book is to investigate the suitability and applicability of available methods for analyzing the human and ecological risks involved in the release of genetically-modified microorganisms. Main topics include: - risk analysis and assessment; approach to safety assurance; - inventory of available scientific risk assessment methods for biotechnology; - identification of methodology gaps and research needs in biology, ecology or other disciplines; - development of a general framework to guide future biotechnology risk assessment efforts; - international regulatory activities.

Organic chemicals constitute minor gaseous components of the earth's atmosphere. Despite low concentrations they play an important role in the global processes influencing the composition of our atmosphere. The author summarizes the multidisciplinary data on sources and thermo- and photochemical transformations of organic components in the atmosphere. Modern methods of atmospheric microimpurity analysis are explained. Models for their time-dimensional distribution both in the urban atmosphere and in unpolluted air are developed. The book provides a unique source of contemporary information for scientists involved in atmospheric chemistry, meteorology, ecology and geophysics.

"Dredged Material and Mine Tailings" are two of the same thing once they are deposited on land: they must be safe-guarded, wash-out must be prevented, and they must be protected by a plantcover. This comprehensive treatise covers both important aspects of their management: "In Chemistry and " "Biology of Solid Waste" the principles and assessment are scientifically studied and discussed, while "Environmental " "Management of Solid Waste" turns to the practical applications, such as prediction, restoration and management. Previously, dredged material was a commodity, it could be sold as soil, e.g. to gardeners. In the meantime, dredged material from the North Sea (e.g. the Rotterdam or Amsterdam harbor) must be treated as toxic waste. Many environmentalists, managers and companies do not know how to solve the inherent problems. This new work deals with the chemical, physical and biological principles; the biological and geochemical assessment; the prediction of effects and treatment; and finally, with the restoration and revegetation. It is written by many leading scientists in the various fields, and will prove invaluable for scientists, managers and politicians who are concerned with the present environmental situation.

This book encourages and demonstrates an innovative approach to the design and operation of urban wastewater systems: integrated modelling and control. Consideration of sewer system, wastewater treatment plant and receiving water body as a single system (rather than as three moderately independent units as before) opens up new types of analyses and new control algorithms for urban wastewater systems. After a comprehensive review of the literature of various fields including processes affecting water flow and quality in urban wastewater systems and their description by different types of models, this book also introduces some of the fundamental concepts of the operation of such systems. It discusses conventional as well as innovative control approaches - ranging from control by simple set-points to elaborate hierarchical control concepts taking into account the water flow and the quality of sewer systems, treatment plants and receiving water body. Thus it will enable the researcher as well as the practising engineer to analyse and to implement various types of control for a particular case study site.In order to illustrate the concepts developed, a detailed simulation study, covering the complete urban wastewater system, is presented. The conclusions drawn demonstrate that the application of innovative control concepts can lead to improved performance of wastewater systems. In addition, a comprehensive survey of mathematical optimisation methods is presented. This book can assist the practising engineer and the student to gain knowledge of all aspects of wastewater systems. To the researcher, this book provides a thorough survey of existing simulation and control concepts and inspiration for further work.

Synthetic and semi-synthetic polymeric materials were originally developed for their durability and resistance to all forms of degradation including biodegradation. Such materials are currently widely accepted because of their ease of processability and amenability to provide a large variety of cost effective items that help to enhance the comfort and quality of life in the modern industrial society. However, this widespread utilization of plastics has contributed to a serious plastic waste burden, and the expectation for the 21st century is for an increased demand for polymeric material. This volume focuses on a more rational utilization of resources in the fabrication, consumption and disposal of plastic items, specifically: -Environmentally Degradable Polymeric Materials (EDPs); -Water-soluble/Swellable Biodegradable Polymers; -EDPs from Renewable Resources; -Biopolymers; -Bioresorbable Materials for Biomedical Applications; -Biorelated Polymers; -Standards and Regulations on EDPs.

Nowadays, major environmental issues are the object of large public debates de- spite the fact that scientific knowledge is often insufficient to draw unequivocal conclusions. Such is the case in the ongoing debate regarding the specific contri- butions of anthropogenic greenhouse gas emissions and of natural climate changes to global warming. At least 10 to 20 years of additional observations will be re- quired, before we will be able to conclude, with certainty, on this subject. In the mean time, and as directed by their immediate interests, people will continue to promote contradictory opinions. The media are, in part, responsible for perpetuat- ing such debates in that they convey indiscriminately the opinion of highly credi- ble scientists as that of dogmatic researchers, the latter, unfortunately too often expressing working hypotheses as established facts. Naturally, in a similarly mis- informed manner, pressure groups tend to support the researcher whose opinions most closely represent either their particular ideological battles or their economic interests and, hence, in their own way, add further to the confusion and obscurity of the debate. Only a few years ago, mercury (Hg)contamination in hydroelectric reservoirs was the object of such media and social biases. At the time, analytical data used to support the discourse were themselves uncertain and numerous hypotheses, often times fanciful, were proposed and hastily "delivered" to the public.

This book analyses the treatment of uncertainties within risk management and regulation for hazardous wastes, in five national case-studies. It is shown that, although institutional uncertainties vary between national political cultures, regulatory bureaucracies everywhere understate these more fundamental uncertainties (which are often structural conflicts, of different rationalities) and define them instead as marginal technical uncertainties or imprecision in risk-definitions. Close comparative analysis shows that technical regulatory standards depend upon their local institutional setting in systematic ways, so that conventional regulatory emphasis on technical precision or standardisation should be replaced by greater social negotiation, and educated public involvement and control. Readers will find the book valuable for its novel analytical approach especially in relation to public acceptance issues, and the argument for fresh practical approaches derived from this; in addition there is new information and analysis from the descriptive materials in case studies. Its main aim is to stimulate fresh thinking and approaches to an urgent problem.

This publication constitutes the Proceedings of a Workshop held in Bordeaux (France) on 8th - 10th October, 1980, under the auspices of the Commissior: of the European Communities, as part of the CEC research programme on 'Effluents from Livestock' and the Concerted Action COST 68 bis 'Treatment and Use of Sewage Sludge'. Major changes have taken place in livestock production techniques in recent years. One of the most important developments has been in the field of animal nutrition. Animals are fed to gain maximum liveweight in close relationship with market requirements for carcass and meat quality. With regard to pig production, dietary formulation is based on scientific principles and feed includes a large variety of ingredients to supply optimum feed rations for 'standardised' animals. In order to increase growth rate and to improve feed conversion, copper is added to the ratio s of fattening pigs in a number of countries, in accordance with the provisions of Council Directives concerning additives in feedingstuffs, as last amended by the 23rd Commission Directive of 4th July 1980.

The agricultural value of sewage sludges is well known and a lot of published data has demonstrated the positive effects of sludge appli cations on plant growth and yield. These effects are probably due mainly to the nitrogen and phosphorus content of sewage sludges. But, as sludges are more organic than mineral, we can expect an effect of the organic matter added to the soil on soil fertility. Certainly, in the future, landspreading of sludges will be regulated, taking into account pollution hazards for waters (excess of nitrogen and phosphorus supply compared to plant needs and soil storage capacities) and for soils (excess of heavy metals supply and build up in soils). There will be regulations fixing what low level of sludges may be spread each year, decreasing their comparative value with respect to mineral fertilizers. In this eventuality, the organic value of sludges will take on a greater importance and several questions arise: - what is the lowest amount of sludge to be spread to have an immediate effect on soil physical properties? - are sludges effective on soil physical properties when spreading repeated low amounts? On the other hand, organic matter and soil biology are closely linked and there are few data on the possible effects - beneficial or detrimenta- on soil organisms."

The identification of inputs and outputs is the first and probably most important step in testing and analyzing complex systems. Following accepted natural laws such as the conservation of mass and the principle of electroneutrality, the input/output analysis of the system, be it steady or in connection with perturbations will reveal the status dynamic, will identify whether changes are reversible or irreversible and whether changing the input will cause a hysteresis response. Moreover, measurements ofinput and output fluxes can indicate the storage capacity ofa system, its resilience to buffer or amplify variations of the external input, and it can identify structural changes. Therefore, to a certain extent, the input/output analysis can facilitate predictions about the ecosystem stability. The measurement of fluxes and the determination of inputs and outputs of eco systems are, in many aspects, analogous to measurements done by engineers when testing an electronic apparatus. The first step is the measurement ofthe input/output properties of the instrument as a whole, or ofvarious circuit boards, and the compari. son ofthese with the expected variations of the original design. Varying input and out. put can give valuable information about the stability and the regulatory properties of the device. Nevertheless, only the circuit as an entity has specific properties which cannot be anticipated if the individual components are investigated regardless oftheir position. Also, the instrument as a whole will have different input/output properties than its subcircuits."

Risk assessment has come to assume acute importance in the former Soviet Union since money is so scarce, yet the needs for cleanup are so huge. Other factors contribute to this situation, too: New leaders are still emerging, and governmental structures are still evolving. This creates a particular difficulty for environmentalists who attempt to become involved in the risk assessment process. New information continues to surface on the fallout from Chernobyl and its consequences for human health. Scientists are still debating the effects of low doses of radiation delivered over a long period of time. This type of contamination is especially prevalent in the Russian North, for example, as a result of the dumping of nuclear submarine reactors into the Kara and Barents Seas. This book examines the complexities of risk assessment in the FSU at this unique time in history.

Over the past two decades, this environmental conference series has emerged to be come one of the major international forums on the chemical aspects of environmental pro tection. The forum is called Chemistry for the Protection of the Environment (CPE). The sponsors of this CPE series have included the Chemical Societies of Poland, France, Bel gium, Italy, Egypt, and the U.S.A., the American Institute of Chemical Engineers, the American Society of Testing and Materials, the International Ozone Association, the United Nations Industrial Development Organization, the Ministries of the Environment of Poland, France, Belgium, and Italy, U.S. Agency for International Development, U.S. Environmental Protection Agency, more than twenty universities and institutes of higher learning, and five national academies of sciences. The first meeting in this series was organized by Prof. Pawlowski and Dr. Lacy in 1976 at the Marie Curie-Sklodowska University in Lublin, Poland. The conference dealt with various physicochemical methodologies for water and wastewater treatment research projects that were jointly sponsored by U.S. EPA and Poland."

Disposal of organic sludge and liquid agricultural wastes is a universal problem. Their production cannot be halted and as steps are taken to maintain or improve the quality of rivers and lakes it grows in quanti ty. The Commission's early awareness of the need for action to prepare for substantial growth in the Community's' sludge disposal problem led to the setting up of the COST 68 project to coordinate and guide European research and development work with particular emphasis on recycling sludge to agricultural land. Two years ago the field of research activi ties was extended to liquid agricultural wastes. This Symposium is the latest opportunity to provide a comprehensive review of the results of the project, to define current trends in practice and to establish by discussion the priorities for research over the next few years. The development of instrumentation and of analytical techniques during the period has extended our knowledge of the organic and inorganic constituents of sewage sludge and agricultural wastes and enabled us more readily to identify and measure the risks to which our general environment may be exposed when disposing of it. This evolution of understanding is a continuing process and an essential guide to the modification of disposal practices to achieve safer and more efficient operations. However, it is important to take a broad view of the application of research findings in the light of the considerable contrast in conditions in different parts of the world.

In the past decades, environmental scientists, economists and physicists have been juggling critical issues within environmental strategies and environmental management styles in order to find a feasible medium between limited resources, long term demands and objectives, and interest groups. In the search for best management alternatives, practice has undergone a pendulum swing between stages that can be characterised as frontier economics, radical environmentalism, resource management/allocation, selective environmentalism and sustainable environmental management. The next stage of management must answer such questions as: Can there be a global - uniform environmental strategy?', or Based on their characteristics, can different issues, different regions and different applications have unique environmental strategies?' Based on this premise, the next stage of management may be identified as risk based sustainable environmental management. The goal of this style will be the risk based, long term, harmonious management of economic resources and environmental preservation for health, safety and prosperity of sustainable populations. When evaluation of risk or risk based ranking of management alternatives enter the picture as part of the overall puzzle, then social policy, ethics and health issues assume a very important role in the management strategy. Economic incentives and environmental constraints have to be considered harmoniously, the main emphasis being placed on protection and preservation of human health and the long term sustaining of populations.

This book is based upon contributions to a Scandinavian conference on Transport, Agriculture and the Environment in a Regional and National Development Per spective: Quantitative and Modelling Approaches, organised by AKF, the Institute of Local Government Studies, Denmark, which was held on the Danish island of Bornholm in December 1993. The chapters represent leading edge research in Scandinavia at the end of 1993 into modelling relationships between the economy and the environment, embracing both regional and sectoral perspectives. The publication of this volume will hopefully contribute to dissemination of knowledge about the very active Scandinavian research tradition in this field, a research tradition which is related to a long-standing engagement of Scandinavian countries with environmental issues. The contributors come from Denmark, Norway and Sweden and the collection is prefaced by two chapters from well-known Dutch researchers, traditionally re garded by Scandinavians as close neighbours to the Scandinavian modelling tradition. The support of S0M (Society, Economy and Environment), an open research centre financed by the Danish Environmental Research Programme, and of AKF in the organisation of the original conference and the preparation of this book is gratefully acknowledged. It was with great sadness that the editors learned of the death of one of the contri butors, Poul Erik Stryg, during the preparation of the book."

"Dredged Material and Mine Tailings" are two of the same thing once they are deposited on land: they must be safe-guarded, wash-out must be prevented, and they must be protected by a plantcover. This comprehensive two-volume treatise covers both important aspects of their management: "Environmental " "Management of Solid Waste" turns to the practical applications, such as prediction, restoration and management, while in "Chemistry and Biology of Solid Waste" the principles and assessment are scientifically studied and discussed. Previously, dredged material was a commodity, it could be sold as soil, e. g. to gardeners. In the meantime, dredged material from the North Sea (e.g. the Rotterdam or Amsterdam harbor) must be treated as hazardous waste. Many environmentalists, managers and companies do not know how to solve the inherent problems. This new work deals with the chemical, physical and biological principles; the biological and geochemical assessment; the prediction of effects and treatment; and finally, with restoration and revegetation. It is written by many leading scientists in the various fields, and will prove invaluable for managers and politicians who are concerned with the present environmental situation.

The Australasia-Pacific Region supports approximately 50% of the world's population. The last half-century has witnessed a rapid increase in the regional population, agricultural productivity, industrial activities and trade within the region. Both the demand for increased food production and the desire to improve the economic conditions have affected regional environmental quality. This volume presents an overview of the fate of contaminants in the soil environment; current soil management factors used to control contaminant impacts, issues related to sludge and effluent disposals in the soil environment; legal, health and social impacts of contaminated land, remediation approaches and strategies to manage contaminated land, some of the problems associated with environmental degradation in the Australasia-Pacific Region and steps that we need to take to safeguard our environment.

Regional Approaches to Water Pollution in the Environment integrates knowledge and experience on pollution problems related to industrial, agricultural and municipal activities and former military sites, with special emphasis on the Black Triangle: the region situated at the borders between North Bohemia, Polish Lower Silesia and South Saxony. Here, some five million inhabitants live in an area of brown coal basins having the highest emissions of sulphuric and nitrogen emission in the whole of Europe. The large-scale damage in this region is due to obsolete technology and insufficient equipment for monitoring emissions. Health effects are severe, and controlling the pollution can only be done at high cost. There is thus a need to exchange knowledge and experience on methods for evaluating the expected effects of measures and purification techniques to remedy ground and surface water pollution.

In March, 1983 a workshop on Pollutants in Porous Media was hosted by the Institute of Soils and Water of the Agricultural Research Organi zation in Bet Dagan, Israel. At this workshop, the unsaturated zone be tween the soil surface and groundwater was the focal point of discus sions for scientists from various disciplines such as soil chemists, physicists, biologists and environmental engineers. Since then, the prob lem of soil and water pollution has only worsened as more and more cases of pollution caused by human activities including agriculture and industry have been revealed. A great deal of work has been carried out by environmental scientists since 1983 in elucidating the behavior of the many classes of pollutants and the complex physical, chemical, and bio logical transformations which they undergo as they move through the soil to the vadose zone and, in many cases, the groundwater. In light of this, it was felt that another meeting of specialists from the many disciplines which deal with this subject was necessary and so a Second International Workshop on the Behavior of Pollutants in Porous Media, sponsored by IUPAC (the International Union of Pure and Applied Chemistry) and IAHS (the International Association of Hydrological Sciences), was organized and held in the Institute of Soils and Water of the Agricultural Research Organization in Bet Dagan, Israel during 1987. June, The present volume is a selection of the talks presented at this second workshop and deals only with toxic organic chemicals in porous media."

The protection of groundwater resources has emerged in recent years as a high priority topic on the agenda of many countries. In responding to the growing concern over deteriorating groundwater quality, many countries are developing a comprehensive regulatory framework for the management of subsurface water resources with management referring to both quantity and quality aspects. Within this framework, groundwater models are rapidly coming to playa central role in the development of protection and rehabilitation strategies. These models provide forecasts of the future state of the groundwater aquifer systems and/or the unsaturated zone in response to proposed management initiatives. For example, models will predict the effects of implementing a proposed management scheme on water levels and on the transport and fate of pollutants. The models are now used in the formulation of policies and regulations, the issuing of permits, design of monitoring and data collection systems, and the development of enforcement actions. The growth in the use of these sophisticated tools has led to many unforeseen problems in groundwater management. Lingering issues include reliability of codes, quality assurance in model development and applications, efficient utiliza tion of human and material resources, technology transfer and training. Some issues have legal ramifications, as in cases where the applications of models have been contested in courts."

ACKNOWLEDGEMENTS IX PART I CONFERENCE SUMMARY STATEMENT R. W. BROCKSEN, W. CHOW, E. D. DAUGHERTY, Y. G. MUSSALLI, J. WISNIEWSKI and A. L. WOODIS I Clean Water: Factors that Influence its Availability, Quality and its Use: Summary of the International Water Conference 3-7 PART II WATER RESOURCE OVERVIEWS S. PECK I Managing and Protecting Our Water Resources 11-20 R. BROCKSEN, W. CHOW and K. CONNOR I Addressing Electric Utility Surface Water Challenges 21-29 C. LOHSE-HANSON I Lake Superior Binational Program: The Role of Electric Utilities 31-40 J. A. VEIL and D. O. MOSES I Consequences of Proposed Changes to Clean Water Act Thermal Discharges 41-52 PART III ECOLOGICAL I HEALTH RISKS c. SEIGNEUR, E. CONSTANTINOU and L. LEVIN I Multipathway Health Risk Assessment of Power Plant Water Discharges 55-64 C. W. CHEN, J. HERR, R. A. GOLDSTEIN, F. J. SAGONA, K. E. RYLANT and G. E. HAUSER I Watershed Risk Analysis Model for TVA's Holston River Basin 65-70 S. FERSON, L. R. GINZBURG and R. A. GOLDSTEIN I Inferring Ecological Risk from Toxicity Bioassays 71-82 C. ARQUIETT, M. GERKE and I. DATSKOU I Evaluation of Contaminated Groundwater Cleanup Objectives 83-92 G. L. BOWIE, J. G. SANDERS, G. F. RIEDEL, C. C. GILMOUR, D. L. BREITBURG, G. A. CUTIER and D. B. PORCELLA / Assessing Selenium Cycling and Accumulation in Aquatic Ecosystems 93-104 D. W. RODGERS, J. SCHRODER and L.

Three symposia on environmental geochemistry in tropical countries, held in Niter6i, Brazil (1993), in Cartagena, Colombia (1996) and in Nova Friburgo, Brazil (1999), made it very clear that tropical geochemistry is of world standard and fast increasing in multi disciplinarily and impact on important geochemical paradigms. It has additionally strong links with the economy of tropical countries, such as mining and industrialisa tion and is in full development for treating environmental problems caused by human activities of urban or industrial origin. We must compliment Prof. Jorge Abriio and his colleagues in Brazil and Dr. Gloria Prieto and her colleagues in Colombia for these ini tiatives. The participation of respectively 180 and 150 scientists, coming from 15 different countries for the first and second symposia, has shown that a large interest exists for tropical environmental geochemistry. It also demonstrates the necessity to understand tropical environmental problems. The organisation of a large international symposium is not possible without the assistance of state and federal authorities, for which those of Brazil and Colombia have to be complimented. The 3rd Symposium on Environmental Geochemistry in Tropical Countries was the last of the series and was attended by 22 countries and 170 participants and treated a number of related environmental and economic problems."

Pulp and paper production has increased globally and will continue to increase in the near future. Approximately 155 million tons of wood pulp is produced worldwide and about 260 million is projected for the year 2010. To be able to cope with increasing demand, an increase in productivity and improved environmental performance is needed as the industry is also under constant pressure to reduce and modify environmental emissions to air and water. The authors give updated information on various biotechnological processes useful in the pulp and paper industry which could help in reducing the environmental pollution problem, in addition to other benefits. Various chapters deal with the latest developments in such areas as raw material preparation, pulping, bleaching, water management, waste treatment and utilization. The book also covers the environmental regulations in various parts of the world as well as the role of biotechnology in reducing environmental problems.