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141.
The SAFIRA in situ pilot plant in Bitterfeld, Saxonia-Anhalt, Germany, currently serves as the test site for eight different in situ approaches to remediate anoxic chlorobenzene (CB)-contaminated ground water. Two reactors, both filled with originallignite-containing aquifer material, are designed for themicrobiological in situ remediation of the ground water bythe indigenous microbial consortia. In this study, thehydrogeological, chemical and microbiological conditions of theinflowing ground water and reactor filling material are presented,in order to establish the scientific basis for the start of thebioremediation process itself. The reactors were put intooperation in June 1999. In the following, inflow CB concentrationsin the ground water varied between 22 and 33 mg L-1; achemical steady state for CB in both reactors was reachedafter 210 till 260 days operation time. The sediments werecolonized by high numbers of aerobic, iron-reducing anddenitrifying bacteria, as determined after 244 and 285 days ofoperation time. Furthermore, aerobic CB-degrading bacteria weredetected in all reactor zones. Comparative sequence analysis of16S rDNA gene clone libraries suggest the dominance of Proteobacteria (Comamonadaceae, Alcaligenaceae, Gallionella group, Acidithiobacillus) and members of theclass of low G+C gram-positive bacteria in the reactorsediments. In the inflowing ground water, sequences withphylogenetic affiliation to sulfate-reducing bacteria andsequences not affiliated with the known phyla of Bacteria, were found.  相似文献   
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Risk assessment of contaminated sites from abandoned ammunition plants follows a multi-stage procedure with its own specific requirements for the toxicological assessment of chemical contaminants. Thus, the 22 explosives and related compounds (STVs) were classified according to carcinogenicity, genotoxicity and evaluation numbers for their toxicological potential (ENs). These characteristics permit a specific toxicological assessment and ranking at the stage of “historical reconnaissance”, independent of an evaluation of the contaminant concentrations. With a view to “orientative site evaluation” for the assessment of explosives and related compounds in groundwater and drinking water, toxicologically related guide values based on the ENs of toxicological potential as well as TDI-based guide values for STVs in soil were derived as based on toxicologically safe body doses and lifelong exposure (TDI=Tolerable Daily Intake). For regulatory purposes, substance related precautionary values are defined for probable carcinogens and contaminants with essential lacks in the toxicological data base.  相似文献   
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environmental auditing must be rejected if the aim is to make companies introduce a specific management concept. Rather, it is preferable to leave the search for effective environmental protection strategies to the competitive system, especially since the criteria for environment-oriented management in the European Community audit proposal are without substance. Environmental auditing can, however, assume a complementary function in the framework of an overall environmental policy if it is designed as an information tool with which companies provide information on the development of environmental problems deriving from their manufacturing processes and products. However, the model required to establish a framework of quantity and evaluation criteria is not available. Further, auditing does not cover products. Similarly, there are no proposals defining the evaluation procedure for ecological resource scarcity. Thus, the attempt of the Commission of the European Communities to create the elementary prerequisites for consistent and verifiable environmental auditing in the corporate sector has failed.  相似文献   
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Asian nations are currently facing a number of challenges, including environmental degradation and growing societal inequalities, in the course of their rapid economic growth and industrialization. Under such conditions, it is of critical importance to develop appropriate assessment tools with which to comprehensively measure the sustainability status of a region in order to guide its transformation into a sustainable society. This paper proposes a method of sustainability assessment consisting of the three components of environment, resource, and socio-economic with aggregated time-series scores. This method can demonstrate the relative sustainability scores of targeted regions for different time periods, thereby, enabling the comparison of relative sustainability status for different regions over these periods. We carried out a case study of Chinese provinces for the years 2000 and 2005 using the proposed method and confirmed its applicability as the indicative type of sustainability assessment at the regional level, while actually investigating the sustainability status and its chronological changes. The results indicated that aggregate sustainability index scores improved between 2000 and 2005 in most provinces, mainly due to significant improvement in the scores for the socio-economic component, whereas the scores for the environment component deteriorated in some provinces over the study period. Our method proves to be effective in analyzing the relative sustainability status among targeted regions for different time periods in the form of aggregate scores, paving the way for practical applications, such as policy analysis, in the pursuit of a sustainable society.  相似文献   
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