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Summary The Yellow River is renowned for its life-endangering floods, a problem augmented by the continuous heavy siltation of its lower flood plain. Major dam and reservoir projects have both positive and negative environmental impacts, and their construction requires careful environmental consideration. This paper outlines the key findings of environmental impact assessment reports related to the Xiaolangdi Yellow River dam/reservoir project. The authors conclude that the project, as planned, should provide an optimal mix of both economic and environmental benefits.This paper is modified from a presentation given to the 1993 Annual Meeting of the International Association for Impact Assessment (IAIA) in Shanghai, China.  相似文献   
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ABSTRACT: This study was to designed to determine concentrations of selected metals, organic compounds, pesticides, and conventional pollutants in stormwater runoff from two North Carolina businesses in each of the following five general industrial groups: auto salvage, metal fabrication, scrap and recycling, vehicle maintenance, and wood preserving facilities. The sampling procedure involved collecting a first flush sample of runoff from a single storm event and both first flush and composite samples of runoff from three consecutive storm events. Analysis of samples collected during the first flush indicated that zinc and copper were the most common of the 13 metals included in the analysis. Additional analysis documented that several volatile organic, semi-volatile organic, or pesticide compounds including acrolein, methylene chloride, xylenes, toluene, tetrachloroethylene, trichloroethylene, pentachlorophenol, and aldrin were also found in the first flush samples. Concentrations of aggregate organics, nitrogen, phosphorus, and sediment were determined in both first flush and three-hour composite samples. Concentrations of pollutants in first flush samples were similar to those in corresponding composite samples.  相似文献   
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ABSTRACT Financing and repayment provisions of western water projects effect transfers of income among federal taxpayers, electric power users, local water users, and property owners. We use the Bonneville Unit of the Central Utah Project as a case study in the distribution of municipal and industrial water costs. We examine the distribution of costs among taxpayers and water users in different political/geographical jurisdictions, and how this distribution is affected by water law, cost allocation procedures, and the choice of revenue source for local repayment of reimbursable costs. In light of the magnitude of distributional effects of present water policy, we conclude that lack of open debate on water issues is unfortunate. We conclude with speculation on the relationship of western water policy to the motivation of western water leaders who are instrumental in its formulation  相似文献   
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