Assessment of Heavy Metal and PAH Contamination of Urban Streambed Sediments on Macroinvertebrates

The results from measuring PAH and metal contamination together with macroinvertebrate communities at 62 headwater stream sites gives a significant insight into the range and scale of contamination. Monitoring streambed sediments at 62 sites from rural to inner city and in industrial locations presented a unique opportunity to distinguish the conditions that enhance pollution runoff at sites that are less obviously `at risk' and to compare these results with sites of expected high contamination, for example in industrial areas and at motorway junctions. We used pCCA (partial Canonical Correspondence Analysis) to tease out the relationships between individual macroinvertebrate families and specific metal and PAH contaminants, and showed that it is not always the metals and PAHs with the greatest total concentrations that are doing the damage to the ecology. Ni and Zn are the critical metals, while benzo(b)fluoranthene, anthracene and fluoranthene are the most contaminating PAHs. The results identify previously unrecognized `high risk' pollution sources, lay byes used for commercial parking, on-street residential parking areas, and the junctions at the bottom of hills with traffic lights, where surface runoff feeds rapidly to the streams. While this study looks at sites across Yorkshire, UK, it clearly has a broader significance for understanding contamination risks from diffuse runoff as a prerequisite for effective sustainable urban drainage system (SUDS) agendas and the protection of urban stream ecology.     

The Identification of Xenobiotics in the New UK Context of Drinking Water Safety Planning and Related Environmental Legislation

Recent European environmental legislation (the Water Framework Directive, the Environmental Liability Directive, and the REACH Regulation) should provide better protection of terrestrial water bodies but their focus is on the more conspicuous pollutants, as opposed to the large number of xenobiotic micro-pollutants that are increasingly being detected in the urban water cycle. The development of Drinking Water Safety Plans (DWSPs), as promoted by the World Health Organization, utilises a proactive risk assessment—risk management approach that necessarily should include micro-pollutants, although currently in the UK micro-pollutants have largely been ignored. The generic assessment of the risks posed by micro-pollutants is proposed and will require a consensus on analytical screening methods, sampling points and frequencies, and a method for prioritising concern, and would enable DWSPs to take fuller account of the risks posed.     

Evaluating Demand Management Aspects of Urban Water Policy. The City of Volos Case,Greece

This paper examines the perspectives of the implementation of a demand-oriented policy concerning residential water use, which covers almost 70% of urban water. Water demand, water pricing policy, as well as building capacity are examined and evaluated in order to investigate the current situation in urban water management in the city of Volos with reference to residential water use. The application of IWR-MAIN model in order to estimate future water needs and form different scenarios for sustainable water resources management together with a field survey in various water issues conducted in 966 citizens of the city of Volos justify the urgent need for the adoption of a demand driven policy.     

The Assessment of Atmospheric Pollution using Satellite Remote Sensing Technology in Large Cities in the Vicinity of Airports

This paper investigates the potential of usingsatellite remotely sensed imagery for assessing atmosphericpollution. A novel approach, which comprised radiativetransfer calculations and pseudo-invariant targets fordetermining aerosol optical thickness has been developed.The key parameter for assessing atmospheric pollution inphotochemical air pollution studies is the aerosol opticalthickness. The need for identifying suitable pseudo-invariantobjects in satellite images of urban areas is of great interest for increasing the potential of earthobservation for monitoring air pollution in such areas. Theidentification of large water bodies and concrete apronsthat can serve as suitable dark and bright targetsrespectively in different geographical areas wasdemonstrated in this study. This study added evidence onthe correlation found between the visibility valuesmeasured at Heathrow Airport area during satellite overpassand aerosol optical thickness derived from Landsat-5 TMband 1 images.     

Relative Contribution of Various Diesel Vehicle Classes to the Thessaloniki Urban Air Pollution

Within the framework of this paper an attempt is made in order to assess the relative contribution of the main diesel vehicle classes; namely, buses, taxis and heavy goods vehicles (HGVs) to the air pollution of the Thessaloniki (Greece) urban area based on an emission factors approach. Data sets refer to the situation before and after the construction of the city ring road. Findings show the significant contribution of the ring road to the urban air pollution decrease. This reduction could be mainly attributed to the observed significant traffic decrease of HGVs in the city center between 1988 and 1998. Small changes have been observed during the same period for the bus and taxi traffic in the city center. Also, the improvement of the diesel fuel quality and the temporal renewal of the diesel vehicles are considered as important factors for the observed temporal decreasing trend of the air pollutants with diesel oil origin.     

Predicting Freshwater Critical Loads from Catchment Characteristics using National Datasets

Maps of freshwater critical loads are used toguide emission strategies for sulphur and nitrogen bothnationally and internationally. Water chemistry data arerequired to calculate critical loads and the production ofnational maps therefore relies on the existence of extensivechemistry datasets. However, the data required to calculatecritical loads are not readily available for all sites. Thisarticle explores how empirical statistical models mightpotentially be used to predict critical loads using nationallyavailable datasets representing a range of catchmentcharacteristics. Initially a global regression model forexplaining freshwater critical load variation across a broadspectrum of catchment types (from lowland agricultural tomountain lakes) throughout mainland Britain is described. Whenattention is focused on more specific catchment types (i.e.upland and non-arable) it is shown that the global model hasless explanatory power. A regionalisation of Great Britain(based on 100 km grid squares) shows that the global modelcannot necessarily be applied successfully within a narrowerregional context. Separate analyses were undertaken on each ofthe regional subsets using backward selection regression. Thevariables emerging as significant predictors variedsubstantially across the regions, as did the explanatory powerof the models. This was also the case when the analysis wasconfined to upland and non-arable catchments. This approachcould be developed so that critical loads assessments can bemade for populations of standing waters rather than simplythose for which water chemistry is available.     

Pesticide Impact Rating Index – A Pesticide Risk Indicator for Water Quality

Pesticide users, natural resource managers, regulators, government agencies and many others are concerned about the off-site impact of pesticides on the environment. Systematic methods of the assessment of potential risk of pesticides to environmental components can serve as valuable tools in decision making and policy formulation. Simple risk indicators have been developed which cover a range of scenarios such as toxicity to organisms, health of farm workers, consumer health, and residues in harvested produce. The authors have developed a software package named Pesticide Impact Rating Index (PIRI) that outputs an improved pesticide risk indicator for water quality. PIRI is a standalone, user-friendly, platform-independent program. It can be used to (i) rank pesticides in terms of their relative pollution potential to groundwater or surface water, and (ii) to compare different land uses in a catchment or at a regional scale in terms of their relative impact on water quality. It is based on pesticides use; the pathway through which the pesticides are released to the water resources (drift, runoff, erosion, leaching) and the value of the water resources threatened. Each component is quantified using pesticide characteristics (including toxicity to organisms at different trophic levels, i.e. fish, daphnia, algae, etc.), environmental and site conditions (e.g. organic carbon content of soil, water input, slope of land, soil loss, recharge rate, depth of water table, etc.). This paper describes two case studies of the application of PIRI in Australia. The comparison of the risk assessment by PIRI on these revealed that PIRI correctly estimated the pollution potential of pesticides in greater than 80% of cases. A GIS version of PIRI is described in a companion paper in this volume. An erratum to this article is available at .     

Resolving complexities in healthcare waste management: a goal programming approach.

The wide variety of activities at healthcare facilities generates different types of waste. There is always a danger of spreading infection due to mishandling of infectious waste or sharps. Hence, a variety of policies and actions have been taken to improve healthcare waste management systems. A large body of literature is available which suggests methods for tackling different problematic situations but management is confronted with a variety of complex problems, such as the choice of technological options to control infection, legal and budget restrictions and the timely removal of waste, which can, at times, conflict with each other. Hence, a planning model is presented that is based on a trans-shipment goal programming approach wherein the waste flow is optimized for multiple objectives under different priority structures or with different relative importance (weights). The use of the model is demonstrated as a decision-making tool that would help the management to understand the effects of their policies on the system performance. The model is validated for a case application representing a real-life situation. It can be easily seen that, in the case in which the management is biased toward a higher level of safety protection towards infection control, they have to compromise on cost control and to some extent on environmental pollution control.     

Potential and Shortcomings of Numerical Weather Prediction Models in Providing Meteorological Data for Urban Air Pollution Forecasting

The last decade progress in numericalweather prediction (NWP) modelling and studies of urbanatmospheric processes for providing meteorological data forurban air pollution forecasting is analysed on examples ofseveral European meteorological centres. Modern nested NWP models are utilising land-use databasesdown to 1 km resolution or finer, and are approaching thenecessary horizontal and vertical resolution suitable forcity scale. The recent scientific developments in the fieldof urban atmospheric physics and the growing availabilityof high-resolution urban surface characteristics datapromise further improvements of the capability of NWPmodels for this aim. A strategy to improve NWP data forthe urban air pollution forecasting is suggested.     

水体重金属-有机物复合污染的协同处理技术研究进展

重金属离子与有机污染物可以通过多种方式共同存在于水体环境中,形成复合污染。本文在简述重金属-有机物复合污染的来源和相互作用机理的基础上,详细阐述了现有的协同处理技术的研究和应用现状,分析了各种技术的原理、效果、优势以及缺陷,为进一步开发新型协同处理技术提供参考,对水体污染的防治具有积极意义。     

Analysis of 3-D Urban Databases with Respect to Pollution Dispersion for a Number of European and American Cities

Dispersion models require as input various geometrical parameters to calculate the flow field and dispersion characteristics in the urban environment. As a result of recent advances in digital photogrammetry and remote sensing, databases of the actual 3-D geometry of city centre areas are now increasingly available. In this work we outline a procedure to reduce this large amount of data to a structured input for urban pollution dispersion models, i.e. to extract the important flow and dispersion parameters from the urban databases. Based on a review of the scientific literature, we have identified a number of parameters relevant to the modelling of pollution dispersion and atmospheric flows in urban areas. These parameters are: the plan and frontal area densities, the plan and frontal area density as a function of height, the distribution of heights, their standard deviation, the aerodynamic roughness length and the sky view factor.These parameters are obtained by analysing urban Digital Elevation Models (DEMs) which are regularly spaced grids of elevation values. Examples of the parameters calculated from high-resolution databases (with pixel size of about 1 m) for three European (London, Toulouse and Berlin) and two North American (Salt Lake City and Los Angeles) cities are presented and discussed. The calculated aerodynamic roughness length was smaller for the European cities than for the North American ones. A multiplicative correction factor to the aerodynamic roughness length is proposed to include the effect of the variability of the building heights.     

Imaging Chemical Patches on Near-surface Atmospheric Dust Particles with NanoSIMS 50 to Identify Material Sources

The increase of traffic and the rising energy consumption mean a challenge to the air pollution control and to environmental protection. Measures of air pollution control concentrated primarily on the reduction of gaseous pollutants. However, in the field of air hygiene in Central Europe, especially the load of near-surface atmospheric dust becomes threatening to human health. A SIMS microprobe for ultra fine feature analysis is used to image the elemental composition at the surface of submicrometer urban dust particles collected at two measurement stations in the Grand Duchy of Luxembourg. The NanoSIMS 50 has been chosen because it creates one intensity image for each selected element in a high spatial resolution down to 50 nm. The atmospheric fine dust consists of a mixture of organic and inorganic compounds. The elemental composition at the surface of particles was studied using a global image segmentation technique to separate the signal from the background of the particles. The analysis of the binary intensity images was carried out using several shape and proximity measures. The patch shape complexity and distribution for industrial/urban particles were found to differ significantly from the solids collected from a forest site. We conclude that the methodology developed in the study is a reliable tool to differentiate between potential sources of airborne particulate matter.     

A Simplified Model for Predicting the Pollution Exchange Coefficient of Small Tidal Embayments

In recent years there has been a significant increase in the development and application of ever more sophisticated multi-dimensional models for solving the hydrodynamic and constituent transport equations which govern the flushing of pollution. However, advanced numerical modelling techniques can sometimes be augmented by alternative mathematical approaches which use simplified analytical solutions to predict the dispersion of contaminants. In the present article, a novel analytical tidal prism model is described for predicting the pollution flushing characteristics of small tidal embayments. The model relates the water quality response of the basin to the external forcing effects of the tide, the initial pollutant loading and the freshwater inflow rate. In general, the pollution flushing not only depends upon the geometry of the embayment and the tidal range but also on the proportion of effluent water which leaves the basin on an ebb tide, mixes with the surrounding coastal water and returns on subsequent flood tides. This effect has been taken into account in the mathematical model by the inclusion of a ‘pollution-return’ parameter. The analytical approach offers a viable and computationally inexpensive alternative to conventional multi-dimensional pollutant transport simulations and, more importantly, provides an increased understanding of the flushing characteristics of semi-enclosed tidal basins. The efficiency of the tidal flushing can be expressed in terms of the pollution exchange coefficient which measures the proportion of water exchanged with the sea each tidal cycle. To demonstrate the accuracy of the proposed mathematical formulation, analytical water quality predictions are compared against experimental pollution data from a 1:400 scale laboratory model of a generic square harbour. The results demonstrate that the analytical approach provides a simple and robust method of determining the water quality response of well-mixed tidal embayments.     

Acidification Trends and the Evolution of Neutralization Mechanisms through Time at the Bear Brook Watershed in Maine (BBWM), U.S.A.

The paired catchment study at the forested Bear Brook Watershed in Maine (BBWM) U.S.A. documents interactions among short- to long-term processes of acidification. In 1987–1989, runoff from the two catchments was nearly identical in quality and quantity. Ammonium sulfate has been added bi-monthly since 1989 to the West Bear catchment at 1800 eq ha^-1 a^-1; the East Bear reference catchment is responding to ambient conditions. Initially, the two catchments had nearly identical chemistry (e.g., Ca²⁺, Mg²⁺, SO₄ ^2-, and alkalinity ≈82, 32, 100, and 5 μeq L^-1, respectively). The manipulated catchment responded initially with increased export of base cations, lower pH and alkalinity, and increased dissolved Al,NO₃ ^- and SO₄ ^2-. Dissolved organic carbon and Si have remained relatively constant. After 7 yr of treatment, the chemical response of runoff switched to declining base cations, with the other analytes continuing their trends; the exports of dissolved and particulate Al, Fe, and P increased substantially as base cations declined. The reference catchment has slowly acidified under ambient conditions, caused by the base cation supply decreasing faster than the decrease of SO₄ ², as pollution abates. Export of Al, Fe and, P is mimicking that of the manipulated watershed, but is lower in magnitude and lags in time. Probable increasing SO₄ ^2- adsorption caused by acidification has moderated the longer-term trends of acidification of both watersheds. The trends of decreasing base cations were interrupted by the effects of several short-term events, including severe ice storm damage to the canopy, unusual snow pack conditions, snow melt and rain storms, and episodic input of marine aerosols. These episodic events alter alkalinity by5 to 15 μeq L^-1 and make it more difficult to determine recovery from pollution abatement.     

纳米技术在环境污染防治中的应用

从大气污染控制与水污染控制等方面综述了纳米技术的研究及应用进展,并展望了纳米技术的发展前景。     

A multiobjective modeling approach to locate multi-compartment containers for urban-sorted waste

The location of multi-compartment sorted waste containers for recycling purposes in cities is an important problem in the context of urban waste management. The costs associated with those facilities and the impacts placed on populations are important concerns. This paper introduces a mixed-integer, multiobjective programming approach to identify the locations and capacities of such facilities. The approach incorporates an optimization model in a Geographical Information System (GIS)-based interactive decision support system that includes four objectives. The first objective minimizes the total investment cost; the second one minimizes the average distance from dwellings to the respective multi-compartment container; the last two objectives address the “pull” and “push” characteristics of the decision problem, one by minimizing the number of individuals too close to any container, and the other by minimizing the number of dwellings too far from the respective multi-compartment container. The model determines the number of facilities to be opened, the respective container capacities, their locations, their respective shares of the total waste of each type to be collected, and the dwellings assigned to each facility. The approach proposed was tested with a case study for the historical center of Coimbra city, Portugal, where a large urban renovation project, addressing about 800 buildings, is being undertaken. This paper demonstrates that the models and techniques incorporated in the interactive decision support system (IDSS) can be used to assist a decision maker (DM) in analyzing this complex problem in a realistically sized urban application. Ten solutions consisting of different combinations of underground containers for the disposal of four types of sorted waste in 12 candidate sites, were generated. These solutions and tradeoffs among the objectives are presented to the DM via tables, graphs, color-coded maps and other graphics. The DM can then use this information to “guide” the IDSS in identifying additional solutions of potential interest. Nevertheless, this research showed that a particular solution with a better objective balance can be identified. The actual sequence of additional solutions generated will depend upon the objectives and preferences of the DM in a specific application.     

Integrated Environmental and Hydraulic Design of Xerias River,Corinthos, Greece,Training Works

The modern design of flood protection and training works in cases of major natural streams and creeks, requires a fine balance between a sound engineering approach in all engineering aspects on one hand, and an environmentally acceptable solution on the other. Progress in integrating environmental and hydraulic design has been achieved over the years due to different factors, like proper collaboration of engineering disciplines, hydraulic modeling enhancement, development and use of suitable materials, amelioration of the construction methods, and proper restoration and use of the affected areas. In this paper, a synopsis of the experience that has been gained by our firm over the years in designing flood protection and river training works for urban and rural areas is presented, including the general design principles to be used as guidelines, and illustrated with the case study of river Xerias, Greece. The river Xerias is located in Peloponnese, Greece. It flows from south to north and has a catchment area of 170 km². For the last 1500 m before discharging into the Corinthian gulf, the river flows through the city of Corinthos. This is the reach, which overflowed and flooded the city during the January 1997 flood, causing a lot of damage and human life casualties.     

Nitrogen management in landfill leachate: Application of SHARON,ANAMMOX and combined SHARON–ANAMMOX process

In today’s context of waste management, landfilling of Municipal Solid Waste (MSW) is considered to be one of the standard practices worldwide. Leachate generated from municipal landfills has become a great threat to the surroundings as it contains high concentration of organics, ammonia and other toxic pollutants. Emphasis has to be placed on the removal of ammonia nitrogen in particular, derived from the nitrogen content of the MSW and it is a long term pollution problem in landfills which determines when the landfill can be considered stable. Several biological processes are available for the removal of ammonia but novel processes such as the Single Reactor System for High Activity Ammonia Removal over Nitrite (SHARON) and Anaerobic Ammonium Oxidation (ANAMMOX) process have great potential and several advantages over conventional processes. The combined SHARON–ANAMMOX process for municipal landfill leachate treatment is a new, innovative and significant approach that requires more research to identify and solve critical issues. This review addresses the operational parameters, microbiology, biochemistry and application of both the processes to remove ammonia from leachate.     

Evaluation of methane emissions from Palermo municipal landfill: Comparison between field measurements and models

Methane (CH₄) diffuse emissions from Municipal Solid Waste (MSW) landfills represent one of the most important anthropogenic sources of greenhouse gas. CH₄ is produced by anaerobic biodegradation of organic matter in landfilled MSW and constitutes a major component of landfill gas (LFG). Gas recovery is a suitable method to effectively control CH₄ emissions from landfill sites and the quantification of CH₄ emissions represents a good tool to evaluate the effectiveness of a gas recovery system in reducing LFG emissions. In particular, LFG emissions can indirectly be evaluated from mass balance equations between LFG production, recovery and oxidation in the landfill, as well as by a direct approach based on LFG emission measurements from the landfill surface. However, up to now few direct measurements of landfill CH₄ diffuse emissions have been reported in the technical literature. In the present study, both modeling and direct emission measuring methodologies have been applied to the case study of Bellolampo landfill located in Palermo, Italy. The main aim of the present study was to evaluate CH₄ diffuse emissions, based on direct measurements carried out with the flux accumulation chamber (static, non-stationary) method, as well as to obtain the CH₄ contoured flux map of the landfill. Such emissions were compared with the estimate achieved by means of CH₄ mass balance equations. The results showed that the emissions obtained by applying the flux chamber method are in good agreement with the ones derived by the application of the mass balance equation, and that the evaluated contoured flux maps represent a reliable tool to locate areas with abnormal emissions in order to optimize the gas recovery system efficiency.     

Formulation of a landfill pollution potential index to compare pollution potential of uncontrolled landfills

Generally speaking, landfilling is one of the prominent methods of waste disposal around the globe, but some under-developed and developing countries still continue to practice uncontrolled open dumping of waste. These uncontrolled landfills pose a relatively high threat to the various elements of the environment in comparison with the conventional engineered landfills that are used in many developed countries. However, some closed, un-engineered landfills do exist in developing countries. This paper presents a novel approach to compare the pollution potential of uncontrolled landfills using an index. The landfill pollution potential index (LPPI) has been developed using the Delphi technique and is an aggregation of six pollution indices that have already been developed for the quantification of different environmental elements. The LPPI is an increasing scale index, in which a higher index value indicates a higher pollution threat. The LPPI of a landfill in Delhi was calculated and the high LPPI value indicates that the respective landfill poses a significant threat to the environment. The LPPI can be used as an aid to diagnose a landfill's pollution potential relative to other landfills and therefore also to rank remediation investments.