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971.
Marvin Waterstone 《Environmental management》1987,11(6):793-804
One major source of water-related health problems is the improper disposal of toxic substances in the environment. Toxic materials leaching from unregulated and unlined pits, ponds, lagoons, and landfills have created a widespread environmental nightmare in the United States and many other parts of the world. At present, there are two major and interrelated components of this problem in the United States. The first is the issue of cleaning up abandoned disposal sites that pose actual or potential threats to water supplies. The second aspect of the problem concerns the necessity of siting proper management, treatment, or disposal facilities in the future. Priorities must be set to allow efficient, effective, and equitable allocation of the scarce resources that are available for accomplishing these tasks.This article examines a number of the issues involved in setting these priorities, and presents the results obtained from a study of risk estimation and evaluation in the context of groundwater contamination by toxic substances. The article introduces a new concept of risk estimation, which is shown to produce more accurate and credible risk analyses. Finally, the relationships between risk credibility and public perceptions of procedural fairness and equity are examined as these factors bear on the institutional aspects of implementing policies for site cleanup and/or facility siting. 相似文献
972.
Alberico Zeppetella 《Journal of Environmental Planning and Management》1988,31(2):103-109
The paper attempts to conceptualise a range of problems arising from project appraisals. The author presents some general considerations concerning the role of social appraisal in territorial planning, the theoretical weaknesses of cost‐benefit analysis in assessing the effects of projects on territorial resources and some questions relating to assessment methodologies and the welfare foundations of social appraisal within planning practices. The author moves away from evaluation as a technical process towards one which also incorporates ‘practical’ knowledge in a process of argumentation. 相似文献
973.
Peter F. M. McLoughlin 《Journal of the American Water Resources Association》1988,24(3):599-607
ABSTRACT: Third World irrigation and drainage systems have experienced major declines recently in both capability and performance. This is due initially to working them well beyond their design capaci-capacities; scouring, sedimentation, and overtopping result. Chronic O&M underfunding then adds heavily to this worsening malaise. International donors have assisted irrigation departments with rehabilitation projects and programs to improve O&M effectiveness on a grand (billions of dollars) scale. Despite their historical propensity to examine, almost fastidiously, program economic justifications (B/C, IRR, etc), the donors apparently have glossed over two basic analytic elements for (a) more spending on O&M as distinct from an equivalent spending on other means to provide farmers with an m3 of water; and (b) different levels of O&M spending on canals and drains. Surely those different levels provide differing benefits, in total, and at the margin. Which level is most economic? This paper identifies these latter analytical issues, posits methodologies key to an O&M spending level analysis, and discusses the information base. Particular attention is paid to identifying relevant costs and benefits, and to suggesting supplementary criteria for O&M spending level selection. The paper is an exercise in delineation of an imminently practical area of irrigation engineering economics. 相似文献
974.
Thanakorn Uan-On Otto J. Helweg 《Journal of the American Water Resources Association》1988,24(2):261-268
ABSTRACT: The Nonlinear Risk-Benefit (NRB) Algorithm includes risk as one of the objectives in a multiple-objective optimization problem. The NRB Algorithm is derived by extending the Surrogate Worth Trade-Off method to quadratic programming. This category of problem is common in water resources planning and design, especially multipurpose reservoir systems. Consequently, an example is given using the algorithm for optimally operating a multipurpose reservoir. 相似文献
975.
AHP法在废水治理工程评价中的应用 总被引:1,自引:0,他引:1
应用层次分析法(AHP)的原理,建立了废水处理工程的评价模型,并结合废水处理的实例进行了研究,结果证明了AHP法是评价废水处理工程的有效方法。 相似文献
976.
论区域环境规划与区域开发环境影响评价在区域开发环境管理中的作用和地位 总被引:3,自引:0,他引:3
回顾了国内外区域开发环境管理的发展历程,简要论述了区域环境规划与区域开发环境影响评价在区域开发环境管理中的作用和地位以及两者的相互关系。 相似文献
977.
The thermal oxidative stability of various formulations based on emulsion-grade ABS was studied by the chemiluminescence technique. Emulsion products were found to be essentially less stable than ionic mass polymerization resins. Among the antioxidants studied, Santonox R is clearly more efficient than Irganox 1076 and Irganox 3114, and its superiority is reflected primarily in improved induction period values. The introduction of Tinuvin 770 and Tinuvin 328 UV stabilizers into emulsion resins does not change the durability of the products. In mixtures where both Irganox 1076 and UV stabilizers are present, a certain antagonistic effect was noted at high UV stabilizer concentrations. 相似文献
978.
In reaction to a paper inEnvironmental Management in which the sense and sensibility of environmental assessments of packaging were questioned, it is argued that these types
of assessments may be very useful, provided the relevant types of questions are posed. These boundary conditions are discussed,
along with an overview of more recent methodological developments with respect to environmental assessment of products. 相似文献
979.
Venkateswara R. Rao 《Environmental management》1995,19(3):313-320
Risk management practices under the current environmental regulations is a long, complex process that considers scientific,
technologic, and management factors to develop various regulatory standards and pollution control measures. Using the mandatory
enforcement approach, sometimes referred to as “command-and-control”, a set of preliminary environmental goals, such as better
air and water qualities, were achieved. However, the information-intensive nature of the risk management process and the lack
of flexibility in conventional regulatory methods to changing economic and technologic realities of the decade has created
interest among risk managers to examine some innovative management approaches. Above all, environmental problems of a global
scale require novel management methods while striving to achieve the desired environmental goals.
As the principal analytical tool in risk management, quantitative risk assessment exerts considerable influence on the risk
management process. Therefore, advances in risk management are closely associated with scientific developments that enhance
the risk assessment process, particularly those efforts aimed at improving human exposure and toxicity assessments. Market
incentives, information dissemination, creative enforcement practices, and interagency and intergovernmental interactions
were identified as the key elements of innovative environmental risk management practices. This paper will present an overview
of the emerging innovative risk management approaches. 相似文献
980.