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211.
Environmental Information Services, Inc. (EIS) publishes detailed reports and offers custom research related to the full spectrum of environmental issues facing corporations. In this new article, EIS reports on the environmental performance, policies, and expenditures of the largest companies in the paper industry, focusing on toxic waste management, and a variety of key policy and expenditure issues. It is important to note that the following article does not contain data on hazardous waste management, penalties, spills, and Superfund sites. This, as well as additional policy and expenditure data, can be obtained from EIS. EIS reports help companies of all sizes benchmark their environmental performance and quality improvement efforts.  相似文献   
212.
Environmental Information Services, Inc. (EIS) publishes detailed reports and offers custom research related to the full spectrum of environmental issues facing corporations. This article highlights several key sections from EIS's new 1998 Petroleum Industry Report. It details the environmental performance, policies, and expenditures of the largest companies in the petroleum industry. EIS industry reports contain data on five key performance criteria—toxic waste management, hazardous waste generation, penalties, spills, and Superfund sites. Here we examine one of those—penalties—and the policies of the three largest companies. In the full report, which can be obtained from EIS, 15 corporations are analyzed based on all the performance criteria.  相似文献   
213.
Environmental Information Services, Inc. (EIS) publishes detailed reports and offers custom research related to the full spectrum of environmental issues facing corporations. In this new article, EIS reports on the compliance performance of the largest companies in the petroleum industry focusing on five key environmental concerns: toxic waste management, air pollution, water pollution, spills, and Superfund. It is important to note that the following article does not contain normalized data and graphs which would adjust findings to various size features (e.g., worldwide revenues per company). This as well as detailed environmental policy and program data on each company can be obtained from EIS. EIS reports help companies of all sizes benchmark their environmental performance and quality improvement efforts.  相似文献   
214.
Companies are increasingly incorporating quantitative environmental data in their benchmarking activities as the search for ways to improve corporate environmental performance continues to expand. The Investor Responsibility Research Center supplies time series data to support several benchmarking activities. This article introduces two new trend indicators that may be used for certain environmental benchmarking applications.  相似文献   
215.
Conventional vacuum relief methodologies are usually protective responses; that is, they accomplish their purpose by substitution of an inert gas (usually nitrogen) for the process gases removed by an external vacuum source, or for condensable vapour collapsed by an internal process mechanism (e.g. condensation). While this approach is theoretically possible for all potential vacuum scenarios, it becomes practically impossible to implement for installations where a rapid phase change can impart near-instantaneous system pressure reductions. The procedure outlined in this paper takes a preventive approach: eliminate the source of vacuum generation before the safe lower system pressure limit is reached. For distillation and other refluxing systems, this vacuum source is usually the main overhead condenser, which is designed to collapse large volumes of condensable vapour. To eliminate the vacuum source requires elimination of the system's ability to rapidly condense vapour. This goal is accomplished by introduction of inert gas directly into the condensing system to ‘blanket’ the heat transfer surface and stop condensation. The procedure determines the rate, amount and location for introduction of inert gas. The required design data include: (i) system starting pressure, (ii) maximum allowable system vacuum, (iii) volume of the condensing system, and (iv) normal system condensing rate. By determining the rate at which the condenser removes vapour volume from the system, and designing an inert gas delivery system to meet or exceed this rate, the vacuum generation potential of the system is effectively eliminated using a much smaller quantity of inert gas than with the more traditional volume substitution methods.  相似文献   
216.
Nonpoint source pollution control requires assessment of the influence of dispersed runoff-contributing areas on downstream water quality. This evaluation must consider two separate phases: site-to-stream loading and downstream fluvial transport. Any model, combination of models, or procedure for making this assessment can be generalized to a simple spatial model or framework, which considers runoff or pollutant loading per unit area and down-stream attenuation, with drainage area as a scaling factor. This spatial model has a probabilistic interpretation and can be used in conjunction with a standard dilution model to give a probabilistic estimate of the impacts at the basin mouth of runoff from a specific upstream contributing area. It is illustrated by applying it to an assessment of the probability that various copper concentrations at the mouth of the urbanized South Platte River basin in Denver, Colorado, USA, will be exceeded as a result of runoff from a subbasin within the city. Determining the probability that a concentration of a pollutant at the basin mouth can be attributed to runoff from a discrete area within the basin is useful for targeting and risk assessment because it enables quantitative risk-based comparisons. The spatial framework is also useful for evaluating management and control options, since actions within the basin can be directly linked to water quality at a downstream point.  相似文献   
217.
This study was an attempt to develop an efficient method of monitoring and assessing how members of a community react to a toxic hazard in their community. The intent was to develop a short instrument which could be applied in multiple settings, or in the same setting several times. The methodology was a short questionnaire that addressed six issues: sources of information about the hazard, beliefs about justice and responsibility, beliefs about why the hazard is a problem, extent of active concern, involvement in community affairs, and satisfaction with life. A mailed questionnaire was developed and tested in a community near an EPA Superfund site in the United States. Results of the effort are discussed relative to the particular community studied, and relative to furthering the assessment technology begun in this research.  相似文献   
218.
In areas where there is little or no topographic relief and where soils, vegetation, geologic structure and other factors are essentially uniform, identification of drainage basin boundaries is difficult or impossible. In such a homogeneous landscape, however, assumptions may be made that the hydrologic and geomorphic controls over drainage basin development are constant within the area. If this is true, it is suggested, the drainage area of a stream is related solely to the stream length and factors governing the length-area relationship are also constant. A simple formula based on these assumptions and the gravity model is proposed which can be used to estimate drainage divides in a homogeneous landscape.  相似文献   
219.
We provide an overview of research related to environmental effects of disposal of coal combustion residues (CCR) in sites in the United States. Our focus is on aspects of CCR that have the potential to negatively influence aquatic organisms and thehealth of aquatic ecosystems. We identify major issues of concern, as well as areas in need of further investigation.Intentional or accidental release of CCR into aquatic systemshas generally been associated with deleterious environmental effects. A large number of metals and trace elements are presentin CCR, some of which are rapidly accumulated to high concentrations by aquatic organisms. Moreover, a variety of biological responses have been observed in organisms following exposure to and accumulation of CCR-related contaminants. In some vertebrates and invertebrates, CCR exposure has led to numerous histopathological, behavioral, and physiological (reproductive, energetic, and endocrinological) effects. Fish kills and extirpation of some fish species have been associatedwith CCR release, as have indirect effects on survival and growth of aquatic animals mediated by changes in resource abundance or quality. Recovery of CCR-impacted sites can be extremely slow due to continued cycling of contaminants withinthe system, even in sites that only received CCR effluents forshort periods of time. The literature synthesis reveals important considerations for future investigations of CCR-impacted sites. Many studies have examined biological responses to CCR with respect to Se concentrations and accumulation because of teratogenic andreproductively toxic effects known to be associated with thiselement. However, the complex mixture of metals and traceelements characteristic of CCR suggests that biologicalassessments of many CCR-contaminated habitats should examine avariety of inorganic compounds in sediments, water, and tissuesbefore causation can be linked to individual CCR components. Most evaluations of effects of CCR in aquatic environments havefocused on lentic systems and the populations of animalsoccupying them. Much less is known about CCR effects in loticsystems, in which the contaminants may be transported downstream,diluted or concentrated in downstream areas, and accumulated bymore transient species. Although some research has examinedaccumulation and effects of contaminants on terrestrial and avianspecies that visit CCR-impacted aquatic sites, more extensiveresearch is also needed in this area. Effects in terrestrial orsemiaquatic species range from accumulation and maternal transferof elements to complete recruitment failure, suggesting that CCReffects need to be examined both within and outside of theaquatic habitats into which CCR is released. Requiring specialattention are waterfowl and amphibians that use CCR-contaminatedsites during specific seasons or life stages and are highlydependent on aquatic habitat quality during those periods.Whether accidentally discharged into natural aquatic systems or present in impoundments that attract wildlife, CCR appears topresent significant risks to aquatic and semiaquatic organisms. Effects may be as subtle as changes in physiology or as drasticas extirpation of entire populations. When examined as a whole,research on responses of aquatic organisms to CCR suggests thatreducing the use of disposal methods that include an aquaticslurry phase may alleviate some environmental risks associatedwith the waste products.  相似文献   
220.
This paper reviews the background that has led to the now almost-universally held opinion in the scientific community that global climate change is occurring and is inescapably linked with anthropogenic activity. The potential implications to human health are considerable and very diverse. These include, for example, the increased direct impacts of heat and of rises in sea level, exacerbated air and water-borne harmful agents, and--associated with all the preceding--the emergence of environmental refugees. Vector-borne diseases, in particular those associated with blood-sucking arthropods such as mosquitoes, may be significantly impacted, including redistribution of some of those diseases to areas not previously affected. Responses to possible impending environmental and public health crises must involve political and socio-economic considerations, adding even greater complexity to what is already a difficult challenge. In some areas, adjustments to national and international public health practices and policies may be effective, at least in the short and medium terms. But in others, more drastic measures will be required. Environmental monitoring, in its widest sense, will play a significant role in the future management of the problem.  相似文献   
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