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ABSTRACT: A stochastic programming framework is developed to evaluate the economic implications of reliability criteria and multiple effluent controls on nonpoint source pollution. An integrated watershed simulation model is used to generate probability distributions for agricultural effluents in surface and ground water resulting from agricultural practices. Results from the planning model indicate that reliability and multiple effluent constraints significantly increase the cost of nonpoint controls but the effects vary by control alternative. The analysis indicates that an evaluation of multiple water quality objectives can be an important planning tool for designing nonpoint source controls for innovative programs to promote cost-effective water quality regulation.  相似文献   
595.
This article outlines the problems related to the exploitation and allocation of undersea resources. The nature and accessibility of undersea petroleum supplies and metalliferous nodules are described in terms of the existing and prospective future economic constraints. Since the majority of such resources lie outside national jurisdictions, their ownership has recently become a major source of international conflict. The character of that conflict is explained, and the prospective solutions under international law are identified. Unilateral action on the part of countries possessing the requisite technologies to exploit these resources is viewed as the most probable near-term outlook, even though it may not satisfy very many aspects of international equity.  相似文献   
596.
Explosives-contaminated groundwater percolating from storage ponds at the Milan Army Ammunition Plant (MAAP) in Milan, Tennessee, into the Claiborne aquifer threatens to contaminate more groundwater—and possibly surface water—in the area. The research described in this article sought to determine whether granular-activated carbon (GAC) could help remove the explosives from the water and to identify which carbons can adsorb the most TNT, RDX, HMX, Tetryl, and others. Two carbons—Atochem, Inc. GAC 830 and Calgon Filtrasorb 300—were found to be promising candidates. As for what to do with the explosives that would be adsorbed, as well as the contaminated carbon, stay tuned.  相似文献   
597.
ABSTRACT: Many of the most productive fishing grounds in the United States are estuaries and bays which are located near population and industrial centers, and therefore subjected to pollution. Observations made on 17 fish species from commercial catches harvested in north Biscayne Bay, Florida, an urban area, showed high numbers of individuals suffering from abnormalities and diseases. Seven groups of disorders most frequently affected bottom feeders. Fin and integumental hemorrhages occurred in all individuals in 26 of 43 catches of Mugil cephalus (striped mullet), and in all individuals in 24 of 30 catches of Micropogon undulatus (Atlantic croaker). Disorders occurring consistently in a location exposed to pollutants, but uncommon in other areas of the species' range, point to environmental stress as a probable cause.  相似文献   
598.
ABSTRACT: Information on raw water quality, treatment process removal efficiency, and distribution system monitoring is essential to the proper management and operation of a water utility system. Microcomputer hardware and software systems using commercially available data base management systems (DBMS) have emerged within the last few years as an effective means of managing, analyzing, and displaying water quality data. Understanding hardware, software, and training requirements is essential to the proper use of these systems. Three types of data base design are common: relational, hierarchical, and network. Only the relational type of data base architecture is widely implemented on microcomputer DBMS. In this paper two examples of the application of DBMS to water utility problems are presented. One example deals with collection and analysis of data concerning the water quality of the Mississippi River. The second example deals with the DBMS as a means of analyzing water quality data in the North Penn Water Authority (NPWA) distribution system.  相似文献   
599.
Zusammenfassung  Die Befunde des in seiner Konzeption in Teil I dargestellten Freilandexperimentes dokumentieren die TNT-Abreicherung und Erholung des Standortes im Laufe der Phytoremediation. Das Monitoring umfasst Erhebungen im Feld (Nitroaromatengehalte in Boden, Sickerwasser und Pflanzen; Erfassung von Bodenorganismen und Streuabbau) und den Einsatz einer Biotestbatterie mit 6 Einzeltests. Die Daten belegen die hohe Heterogenit?t der TNT-Kontamination, eine rasche initiale Abreicherung und eine geringe Verlagerung von Nitroaromaten in Pflanzen und Sickerwasser. Die anf?nglich rasche Transformation des TNT zu Aminodinitrotoluolen l?sst nach 3 Monaten deutlich nach. Mit Hilfe der Biotestbatterie wird die Toxizit?t des Bodens differenziert beurteilbar; die boden-biologischen Befunde lassen Langzeitwirkungen der TNT-Belastung wahrscheinlich werden. Eine Gesamtbeurteilung des Projekts wird im dritten Teil der Artikelserie erfolgen. OnlineFirst: 10. 09. 2001  相似文献   
600.
Den W  Huang C  Li CH 《Chemosphere》2004,57(7):697-709
The effects of cross-substrate interaction to the performance of a gas-phase biotrickling filter for treating a mixture of volatile organic compounds (VOCs), including three structural heterologous in acetone, toluene, and trichloroethylene, were investigated. The biotrickling filter was inoculated with microbial consortium containing at least seven bacterial species utilizing either acetone or toluene, or both, as their carbon sources. In the performance study, the column operating under variable conditions typifying the waste gas emission from the microelectronics fabrication processes achieved a total hydrocarbon (THC) removal efficiency in excess of 85% and a mineralization capacity over 50% for THC mass loading as high as 36.2 g-CH4 m-3h-1. The cross-substrate effects were examined by correlating the relative changes in the mass removal of each substrate with the biodegradative capability of the microbial consortium. The degradation of trichloroethylene was primarily due to co-metabolism by the toluene-oxidizing enzymes, but the results also indicated that trichloroethylene partially induced its own degradation. Concentration increases in acetone appeared to cause a diauxie effect that suppressed degradation of toluene and trichloroethylene, and shifted the microbial population toward the selective acetone-degraders. No irrecoverable toxicity or inhibitory effects were observed throughout the experiments. These results suggest that the relative VOC concentration in the waste gas mixture is a factor as important as the biodegradative function of the microbial consortium, and thus should be carefully evaluated to satisfy the treatment objectives.  相似文献   
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