A Versatile,High Flowrate Tape Sampler

One of the more difficult tasks for the scientific writer is to provide a balanced report of a national effort in a selected area of research and development. The difficulty is compounded when the writer elects to be sole author and has himself shared in the research effort; for he will know his own work best and will be tempted to be spokesman for other research groups of whose work he may not be appreciative.     

Small-scale variability of metals in soil and composite sampling

Soil pollution data is also strongly scattering at small scale. Sampling of composite samples, therefore, is recommended for pollution assessment. Different statistical methods are available to provide information about the accuracy of the sampling process. Autocorrelation and variogram analysis can be applied to investigate spatial relationships. Analysis of variance is a useful method for homogeneity testing. The main source of the total measurement uncertainty is the uncertainty arising from sampling. The sample mass required for analysis can also be estimated using an analysis of variance. The number of increments to be taken for a composite sample can be estimated by means of simple statistical formulae. Analytical results of composite samples obtained from different fusion procedures of increments can be compared by means of multiple mean comparison. The applicability of statistical methods and their advantages are demonstrated for a case study investigating metals in soil at a very small spatial scale. The paper describes important statistical tools for the quantitative assessment of the sampling process. Detailed results clearly depend on the purpose of sampling, the spatial scale of the object under investigation and the specific case study, and have to be determined for each particular case.     

中国燃煤锅炉烟气脱硫技术的发展前景

本文在综述我国燃煤中小型锅炉和电站锅炉烟气脱硫技术现状的基础上，分析了我国燃煤锅炉烟气脱硫技术的发展前景．分析结果指出：我国中小型燃煤锅炉烟气脱硫技术近期是以完善湿法脱硫技术为主，远期将大力发展干法脱硫技术；在电站锅炉烟气脱硫方面，规模较小的电站锅炉将以喷雾干燥法为主要发展方向，大型电站锅炉近期仍以湿式石灰石－石膏法为主，远期将大力发展电子束辐照氨法脱硫脱硝技术。     

Studies on transitory laxative effects of sorbitol and maltitol I: Estimation of 50% effective dose and maximum non-effective dose

The dose-response relationship between low-caloric sweetening agents, sorbitol and maltitol, administered orally in single doses, and the induction of diarrheal symptoms was investigated. Seven healthy male and 7 healthy female Japanese each in their twenties, thirties, and forties, respectively, or a total of 42 subjects were admitted to the study. The 50% laxative effective dose of sorbitol was estimated to be 0.4 g/kg for males and 1.0 g/kg for females and that of maltitol was estimated to be 0.8 g/kg for both males and females. The maximum non-effective dose of sorbitol was estimated to be 0.15 g/kg for males and 0.3 g/kg for females and that of maltitol was estimated to be 0.3 g/kg for both males and females.     

Simple nomenclature for chlorinated camphenes and dihydrocamphenes from which structural information can be directly deduced

The systematic nomenclature for chlorinated camphenes and dihydrocamphenes is rather complicated and confusing. Therefore, a simple structure-related nomenclature is proposed for these compounds, which is based on the same logic as was recently used for the chlorinated bornanes, bomenes and bornadienes. Although final IUPAC rules for the systematic nomenclature for camphenes and dihydrocamphenes have not yet been presented, the present nomenclature can be used for retrieving the correct conformation without the help of extensive tables or computer programmes, and vice versa. When the final IUPAC rules will be presented, the present nomenclature can easily be adjusted, if necessary     

Gamma irradiation of municipal sludge for safe disposal and agricultural use.

Gamma radiation was found to be an effective tool for hygienization of municipal wastewater sludge. The sludge received from the primary settling tank of a municipal wastewater treatment plant was gamma irradiated using a cobalt-60 source in a sludge hygienization research irradiator. The process parameters were adjusted to effectively eliminate coliform bacteria in the sludge and to prevent their regrowth. Irradiated sludge was found to be free of fecal coliform and could be directly disposed after drying in a landfill or used as manure. It could also be used as a medium for growth of Rhizobium sp for obtaining a bio-fertilizer.     

Guidance for the performance evaluation of three-dimensional air quality modeling systems for particulate matter and visibility

Guidance for the performance evaluation of three-dimensional air quality modeling systems for particulate matter and visibility is presented. Four levels are considered: operational, diagnostic, mechanistic, and probabilistic evaluations. First, a comprehensive model evaluation should be conducted in at least two distinct geographical locations and for several meteorological episodes. Next, streamlined evaluations can be conducted for other similar applications if the comprehensive evaluation is deemed satisfactory. In all cases, the operational evaluation alone is insufficient, and some diagnostic evaluation must always be carried out. Recommendations are provided for designing field measurement programs that can provide the data needed for such model performance evaluations.     

A review on the application of microbial toxicity tests for deriving sediment quality guidelines

The results of microbial toxicity tests are needed for the risk assessment of polluted sediments. In comparison with animals the anaerobic microorganisms are more tolerant to natural sediment conditions whereas they are more sensitive for a number of specific pollutants. Microbial toxicity tests from a literature search were classified in seven categories. Category A, B and C use polluted sediments and are applied for sediment monitoring. In category D, a pure chemical is added and the organisms and the test conditions were derived from sediment. Therefore this category can be used for setting sediment quality guidelines which protect sediment functions for the toxic effects of chemicals. In category E, organisms from a polluted site are separated from the sediment and are tested with pure chemicals. Organisms from a more polluted site can be more tolerant to a local pollutant. This is called pollution-induced community tolerance and can be used as evidence for the occurrence of toxic effects in a specific sediment. In category F pure chemicals are tested with a pure culture of microorganisms under sediment conditions. The results of category F tests can be combined with single species tests with animals and plants to obtain sediment quality guidelines sufficient for species protection. This can be compared with the sediment quality guidelines which protect sediment functions. When one of these quality guidelines is exceeded for a compound at a specific location a category E test can be used to determine whether the compound shows toxic effects in that sediment.     

A Practical Look at Environmental Audits

Company self-auditing has become an increasingly attractive option for both government and industry in achieving compliance with environmental laws. For government, it can diminish the need for continual compliance inspections, and, for industry, it can prevent substantial liability. However, auditing can be conducted in a number of ways, and it is important for company management to be aware of its options before selecting a particular approach. This is particularly true of companies with relatively limited resources for such a project. The following article describes some of the more basic options to be considered In identifying an optimal auditing strategy. It also discusses factors which may make one strategy preferable to another. The article concludes with the interesting observation that, in some cases, a formal audit may be neither necessary nor desirable.     

Assessment of the ecological potential of mine-water treatment wetlands using a baseline survey of macroinvertebrate communities

A baseline survey of macroinvertebrate populations in two mine-water treatment wetlands, one treating a net acidic spoil heap discharge and one a net alkaline ferruginous pumped mine water, was undertaken to assess the potential of these systems to provide habitats for faunal communities. Both wetlands were found to be impoverished in comparison to natural wetlands but did sustain a macroinvertebrate community that could support higher organisms. Wetland size and water quality in terms of pH, conductivity and metal concentrations were found to be important factors in determining the quality of the populations supported. Direct toxicity to organisms was unlikely to be the main cause of lower diversity, but the smothering of organisms via the precipitation of iron hydroxides particularly in the early parts of the treatment systems affected macroinvertebrate communities. The presence of areas of open water within the planted systems was found to be important for providing habitats for macroinvertebrates and this should be both a future design and maintenance consideration for environmental managers.     

The dynamics of ecosystems, biodiversity management and social institutions at high northern latitudes

Ecosystems at high latitudes are highly dynamic, influenced by a multitude of large-scale disturbances. Due to global change processes these systems may be expected to be particularly vulnerable, affecting the sustained production of renewable wood resources and abundance of plants and animals on which local cultures depend. In this paper, we assess the implications of new understandings of high northern latitude ecosystems and what must be done to manage systems for resilience. We suggest that the focus of land management should shift from recovery from local disturbance to sustaining ecosystem functions in the face of change and disruption. The role of biodiversity as insurance for allowing a system to reorganize and develop during the disturbance and reorganization phases needs to be addressed in management and policy. We emphasize that the current concepts of ecological reserves and protected areas need to be reconsidered to developp dynamic tools for sustainable management of ecosystems in face of change. Characteristics of what may be considered as customary reserves at high latitudes are often consistent with a more dynamic view of reserves. We suggest new directions for addressing biodiversity management in dynamic landscapes at high latitudes, and provide empirical examples of insights from unconventional perspectives that may help improve the potential for sustainable management of biodiversity and the generation of ecosystem services.     

Modeling tracer diffusion in fractured and unfractured, unsaturated, porous media

A proposed tracer diffusion test for the Exploratory Shaft Facility at Yucca Mountain, NV, is modeled. For the proposed test, a solution containing conservative tracers will be introduced into a borehole in the geologic medium of interest. The tracers will diffuse and advect from the saturated source region into the unsaturated matrix in the surrounding tuff. After some time, the borehole is to be overcored, and tracer concentrations in the fluid will be measured in the core as a function of distance from emplacement. The data will be used to evaluate diffusive behavior and to derive effective diffusion coefficients for the tracers in the specific tuff. Numerical simulations are used to study the effects of effective diffusion coefficient, porosity, saturation, and fracturing on tracer transport. Results are reported for numerical simulations of tests in the Topopah Spring Member and the Tuff of Calico Hills, which have significantly different porosities and saturations. The simulations make the following predictions: The spread of tracer during the test will be sensitive to the effective diffusion coefficient of the tracer. Tracer will diffuse farther in the Topopah Spring Member than in the Tuff of Calico Hills because of the former's lower porosity and saturation. Tracer transport by advection into the Topopah Spring Member will be greater than that into the Tuff of Calico Hills because of capillary effects. While advection will be a significant mechanism for tracer penetration into the Topopah Spring tuff, it will be less significant for tracer penetration into the Calico Hills tuff. The proximity of a single vertical fracture to the source region determines its effects on tracer transport, especially if the fracture diverts fluid flowing from the source region into the matrix.     

Influencing factors and a proposed evaluation methodology for predicting groundwater contamination potential from stormwater infiltration activities.

To offset the detrimental effects of urbanization on groundwater recharge, stormwater managers are focusing on infiltrating much of the runoff from a site that was generated because of development. For this to be effective, tools are required to predict the potential for contamination resulting from this infiltration for many site conditions, because infiltration should be stressed in areas where the least potential for causing groundwater contamination exists. Factors that influence contamination potential include the pollutant concentration in the runoff directed to the infiltration device and the ability of the underlying soil to remove the pollutant. The groundwater contamination potential of some pollutants, even those with high concentrations and moderate-to-high mobilities, can be reduced with proper pretreatment before infiltration. This paper presents a methodology that can be used to evaluate infiltration as an management option and introduces two different levels of models that could be used to evaluate contamination potential.     

The Evolution of the Environmental Quality Concept: From the US EPA Red Book to the European Water Framework Directive

- DOI: http://dx.doi.org/10.1065/espr2006.01.003 Background Water Quality Criteria were firstly defined in the 1970s by the EPA in the USA and the EIFAC in Europe, recognizing the need for protecting water quality in order to allow the use of water resources by man. In the 1990s, the European Commission emphasized the importance of safeguarding structure and function of biologic communities. These approaches were chemically-based. The European Water Framework Directive (WFD) substantially changes the concept of Water Quality, by assuming that a water body needs to be protected as an environmental good and not as a resource to be exploited. In this frame, the biological-ecological quality assumes a prevailing role. Main Features The Water Quality concept introduced by the WFD is a challenge for environmental sciences. Reference conditions should be defined for different typologies of water bodies and for different European ecoregions. Suitable indicators should be developed in order to quantify ecological status and to define what a 'good' ecological status is. Procedures should be developed for correlating the deviation from a good ecological to the effects of multiple stressors on function and structure of the ecosystem. The protection of biodiversity becomes a key objective. In this frame, the traditional procedures for ecotoxicological risk assessment, mainly based on laboratory testing, should be overcome by more site-specific approaches, taking into account the characteristics and the homeostatic capabilities of natural communities. In the paper an overview of the present knowledge and of the new trends in ecotoxicology to get these objectives will be given. A procedure is suggested based on the concept of Species Sensitivity Distribution (SSD). Recommendations and Perspective . The need for more site-specific and ecologically-oriented approaches in ecotoxicology is strongly recommended. The development of new tools for implementing the concept of 'Stress Ecology' has been recently proposed by van Straalen (2003). In the same time, more 'cological realism'is needed in practically applicable procedures for regulatory purposes.     

Designing Treatability Studies for CERCLA Sites: Three Critical Issues

A great urgency has developed in the past few years within the U.S. EPA remediation program to perform treatability studies at Superfund (CERCLA) sites. The major reasons for this urgency is to ensure the selected treatment technology is applicable to the waste characteristics, and that Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) cleanup goals can be achieved. However, prior to conducting a treatability study, three critical issues must be resolved by the site manager. First, what scale and timing are appropriate? Second, should the treatability study be performed by a treatment technology vendor using proprietary equipment and processes, or can a generic study be performed? Third, should the study be performed in the field or should the waste be taken to the laboratory for testing? The objectives of the treatability study will have a major impact on how these issues are resolved. This paper discusses these major issues and provides information for the design and conduct of Superfund treatability programs.     

Guidance for the Performance Evaluation of Three-Dimensional Air Quality Modeling Systems for Particulate Matter and Visibility

ABSTRACT

Guidance for the performance evaluation of three-dimensional air quality modeling systems for particulate matter and visibility is presented. Four levels are considered: operational, diagnostic, mechanistic, and probabilistic evaluations. First, a comprehensive model evaluation should be conducted in at least two distinct geographical locations and for several meteorological episodes. Next, streamlined evaluations can be conducted for other similar applications if the comprehensive evaluation is deemed satisfactory. In all cases, the operational evaluation alone is insufficient, and some diagnostic evaluation must always be carried out. Recommendations are provided for designing field measurement programs that can provide the data needed for such model performance evaluations.     

Further analysis and PMF application to the chemical composition data of IPCAJ's Kashima SPM study

The Industrial Pollution Control Association of Japan (IPCAJ) has conducted an air quality study. A brief summary has already appeared in previous papers. This set of data was not sufficiently analysed. This study attempts to examine the performance of the Positive Matrix Factorisation (PMF), a recently introduced technique in this field, on this multiple-site Kashima data set. The source apportionment study using the PMF model conducted for the Kashima data set identified six factors for each fine and coarse fraction. This result also seems to be appropriate, because spatial distribution and seasonal variation of the contributions for each emission source category could be explained reasonably. The PMF can analyse a data set that may be extracted from different populations, and it seems to be a powerful tool available for these kinds of complicated data sets.     

Multi-substrate, multi-option groundwater transport model

A user friendly, finite-difference groundwater transport model, called “Multi-substrate, Multi-option Groundwater Transport Model (MMGTM)”, has been developed to afford users several options in defining a transport sequence. In addition to advective-dispersive transport, the model incorporates a variety of adsorption and biological decay mechanisms. Adsorption can be simulated for linear, Langmuir, or Freundlich isotherms coupled with equilibrium or non-equilibrium mass transfer. Biological decay can be simulated for first-order or Monod-type approaches, and can be linked to oxygen consumption and transport. Aqueous and sorbed phase decay can be simulated.Further, the transport of two substrates and oxygen can be simulated concurrently and the interaction between them can be described as competitive, diauxic-like or simultaneous. The growth of biomass and its effect as an adsorbent can also be simulated by means of a stoichiometric yield coefficient and a biomass/adsorbent conversion factor. Continuous or pulse input of solute in conjunction with either constant-mass-flux or constant-concentration boundaries can be selected. Menu screens allow the user to configure each problem while parameters can be input individually or called from a separate data file. The input data can be viewed, modified or saved before simulation. Output is visually displayed of the screen as breakthrough and profile curves, while also being saved to an ASCII file on a disk for subsequent processing.     

Aerosol indirect effect during successive contrasting monsoon seasons over Indian subcontinent using MODIS data

Aerosol indirect effect (AIE) was estimated over six Indian regions, which have been identified as main source regions of absorbing aerosol emissions, for four successive contrasting monsoon years, 2001 (normal monsoon rainfall year), 2002 (drought year), 2003 (excess monsoon rainfall year) and 2004 (below normal rainfall year). The AIE has been estimated both for fixed cloud liquid water path (CLWP) and for fixed cloud ice path (CIP) bins, ranging from 1 to 350 gm^?2 at 25 gm^?2 intervals obtained from Moderate resolution imaging spectroradiometer (MODIS). In 2002 and 2004, AIE found to be of positive (Twomey effect) in majority of the fixed CLWP and CIP bins, while in 2001 and 2003 majority of the bins were found to be showing negative indirect effect (Anti-Twomey effect). Changes in circulation patterns during contrasting monsoon seasons, bringing up air mass containing aerosols of different source origins may be the main reason for this positive and negative AIE. The study suggests that AIE could be one of the factors in modulating Indian summer monsoon. However, further research on this topic is to be carried out to establish the relationship between AIE and Indian monsoon rainfall and also AIE values may be parameterized in climate models for better prediction of monsoon.     

Potential pathways and exposure to explain the human body burden of organochlorine compounds: a multivariate statistical analysis of human monitoring in Würzburg, Germany

By means of multivariate statistical analysis of human monitoring in the vicinity of Würzburg it is examined whether the organochlorine levels in blood data of 309 persons can in part be explained by pollution from outdoor and/or indoor air. Although diet is the main source for intake this study concentrated on the remaining sources. Using 12 personal and geographical variables, which describe some aspects or components of indoor or outdoor exposure, the quantities of the different pathways for the intake are calculated and shown. Besides the impact of the indoor air, which can be pointed out for intake at the workplace for some PCB-congeners, also the hypothesis of the existence of an intake from outdoor air for some organochlorine compounds cannot be rejected. Here, the origin is the spatial variation of the pollution, which can be directly traced back to micro-climatic processes, local relief conditions, and the functional set-up of the town.