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31.
Water resources management in the urban areas of the United States to be effective must include dimensions far beyond water supply and sewerage. This paper concerns itself with those problem areas of water resource management outside of potable water supply and sanitary sewers. These areas include flood plain management, greenways and blueways, storm water, vistas of waterways, and other attributes of living in or near a water-related environment. The perceptions and attitudes of the concerned public and community power structure must be known in order to manage the water environment effectively. Methods of measuring these perceptions and attitudes are described and ways in which the resulting citizen-resource can be tapped and used as a management device are explored.  相似文献   
32.
Within a few years all domestic wastewater effluents in the United States will be subjected to a minimum of a properly operated primary and secondary treatment process. This implies a very high degree of removal of the more readily biologically degradable material as measured by the BOD test. This practice will to a large degree negate the value of the BOD test as a pollution parameter. Organic carbon appears to be a more suitable means for determining the strength of a wastewater or for controlling the operation of physical and chemical treatment processes. Studies were conducted to determine the effect of time of passage on the ratio of organic carbon to BOD, COD and carbohydrate. The ratio was found to vary with both time and the state of the sample. The carbon content was reduced to a lesser degree than the other parameters. Organic carbon content appears to correlate better with COD than with BOD. The efficiency of a chemical precipitation process can be determined on the basis of organic carbon removal.  相似文献   
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Industrial ecology is a systemic organizing framework for the many facets of environmental management. It views the industrial world as a natural system, embedded in local ecosystems and the global biosphere. It provides a fundamental understanding of the value of modeling the industrial system on ecosystems to achieve sustainable environmental performance. In this article, the author shows how it offers powerful tools of analysis that complement and enhance those offered by such approaches as Total Quality Environmental Management or pollution prevention.  相似文献   
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The implementation of the Comprehensive Test Ban Treaty is resulting in the construction of a world-wide system of 80 monitoring stations that will be able to detect air-borne radioactivity, not only from atomic bombs but also from other anthropogenic and natural sources. A prototype monitoring station has been operating since April 1996 in Vancouver, BC, Canada. This station provides daily reports of natural radioactivity, including 7Be and decay products of 220Rn (thoron). Data for 212Pb concentrations have been analyzed over a 6-month period. The concentration is reduced by rainfall, high wind velocity, and low temperatures and it also depends on the wind direction, but atmospheric inversions appeared to have little impact. We present a relatively simple model, which is easy to use and which offers predictive powers that can be applied to other similar environmental situations.  相似文献   
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Gray whales are coastal migratory baleen whales that are benthic feeders. Most of their feeding takes place in the northern Pacific Ocean with opportunistic feeding taking place during their migrations and residence on the breeding grounds. The concentrations of organochlorines and trace elements were determined in tissues and stomach contents of juvenile gray whales that were taken on their Arctic feeding grounds in the western Bering Sea during a Russian subsistence harvest. These concentrations were compared to previously published data for contaminants in gray whales that stranded along the west coast of the US during their northbound migration. Feeding in coastal waters during their migrations may present a risk of exposure to toxic chemicals in some regions. The mean concentration (standard error of the mean, SEM) of sigmaPCBs [1400 (130) ng/g, lipid weight] in the blubber of juvenile subsistence whales was significantly lower than the mean level [27,000 (11,000) ng/g, lipid weight] reported previously in juvenile gray whales that stranded in waters off the west coast of the US. Aluminum in stomach contents of the subsistence whales was high compared to other marine mammal species, which is consistent with the ingestion of sediment during feeding. Furthermore, the concentrations of potentially toxic chemicals in tissues were relatively low when compared to the concentrations in tissues of other marine mammals feeding at higher trophic levels. These chemical contaminant data for the subsistence gray whales substantially increase the information available for presumably healthy animals.  相似文献   
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The feasibility of applying the up-flow anaerobicsludge blanket (UASB) treatment for poultry waste (faeces)water was examined. A continuous-flow UASB pilot scalereactor of 3.50 L capacity using mixed culture was operatedfor 95 days to assess the treatability of poultry waste-water and its methane production. The maximum chemicaloxygen demand (COD) removed was found to be 78% whenorganic loading rate (OLR) was 2.9 kg COD m-3 day-1 athydraulic retention times (HRT) of 13.2 hr. The averagebiogas recovery was 0.26 m3 CH4 kg COD with an averagemethane content of 57% at mean temperature of 30 °C.Data indicate more rapid methanogenesis with higher loadingrates and shorter hydraulic retention times. At feedconcentration of 4.8 kg COD m-3 day-1, anaerobic digestionwas severely retarded at all hydraulic retention timetested. This complication in the reactor operations may belinked to build-up of colloidal solids often associated withpoultry waste water and ammonia toxicity. Isolates fromgranular sludge and effluent were found to be facultativeanaerobes most of which were Pseudomonas genera.  相似文献   
40.
In 1992, Eaton Corporation, a major manufacturer of vehicle components and electrical and electronic controls, implemented a fast-track remediation method to expedite the installation of a groundwater recovery and treatment system to contain and mitigate a chlorinated solvent plume at an industrial site. This dual-track method included fast-track and turnkey project management techniques. Our goal was to expedite the containment and removal of identified contamination, which would protect the environment, minimize future liability, and significantly reduce remediation time and costs. This goal was in the best interests of all concerned—Eaton, the community, and the state regulatory agency. This strategy took the project from dual-track concept approval by the regulatory agency to remediation system installation and start-up in less than eight months, cutting over two years from the standard Remediation Investigation/Feasibility Study (RI/FS) approach, with consequent earlier contaminant containment. Total remediation costs were half of what they would have been under the standard RI/FS procedure for this site.  相似文献   
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