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Naturally occurring arsenic in ground water has been a recognised serious hazard in many parts of the world in general and in some south Asian countries in particular. Recently, ground water arsenic contamination has been documented from various parts of Pakistan. In this study arsenic exposures and arsenic attributable health risks are estimated for two potentially impacted areas in Pakistan. The use of early stage biomarkers as proxies for exposure has also been tested from a well characterised field area in West Bengal and their utility to studies in northern Pakistan indicated. In this thesis, an arsenic exposure and risk assessment study was carried out in Allama Iqbal Town Lahore, Pakistan and a preliminary exposure survey carried out in the Peshawar basin, Khyber Pukhtoon Khwa, Pakistan. The major identified exposure routes in both areas was found to be ground water, used for drinking/cooking purposes, and to a lesser extent raw rice. In Allama Iqbal town a median arsenic contamination of 24 µg/L (with maximum value 960 µg/L) in drinking water/cooking water (n=132) derived from ground water sources was found and which is well above the 10 µg/L arsenic WHO provisional guideline value. Rice arsenic concentration (n=86) had a median value of 0.08 mg/kg (range 0 .03 - 0.25 mg/kg), of this 40% - 93% (median 69%) was inorganic. The calculated excess lifetime cancer risk value from drinking/cooking As contaminated water (3.30 × 10-3) and also from both water and rice together for volunteers of Allama Iqbal town Lahore, Pakistan is (3.52 × 10-3) higher than the (10-4-10-6) range typically used as a threshold value by USEPA. Factors such as variations in water and rice supply, diet, dietary pattern, genetics, age are in combination also important in determining human exposure and arsenic attributable health risks in this area. The maximum ground water arsenic contamination value (8 µg/L) found during the study of arsenic contamination in the Peshawar basin was lower than the WHO provisional guide vBiomarkers of arsenic exposure, viz. human hair (n=115), nails (n=144) (toe and finger nails), and urine (n=23) collected from Allama Iqbal town Lahore have a median value of As in hair 0.33 mg/kg (0.03 -14.7 mg/kg), As in nails 0.84 mg/kg (0.53 - 64 mg/kg) (mean 0.94) and for urine median 118 µg/g creatinine (19 - 350 µg/g creatinine) (mean 137 µg/g) for urine. Hair As has a significant correlation (r2=0.63 & p=0.01) with arsenic contents of drinking water as does to some extent nail As (r2=0.24 & p=0.05). Similarly chronic daily intake of water is positively correlated with As content of hair (r2=0.42 & p=0.01). This is also helpful in confirming ground water used for drinking /cooking as the major arsenic exposure route in this area. The biomarkers of arsenic exposure study when applied in West Bengal India gives highly significant association values (r2=0.70 & p=0.01) for cooked rice and chronic daily intake from cooked rice. With the frequent use of rice and being used as a staple food in West Bengal, ingestion of arsenic contaminated rice is being confirmed as a major exposure route in the West Bengal by the biomarkers of exposure: this is in contrast to Allama Iqbal town Lahore where drinking As contaminated water is being confirmed the major exposure route. ICP-MS was used for quantifying the total concentration of arsenic in hair, nails, water, rice and urine. IC- ICP-MS was used for arsenic speciation analysis of urine as well as raw rice. An informed consent based questionnaire survey was used for collection of relevant information.

Seven percent of surface waters in England and Wales are impacted by pollution from abandoned non-ferrous metal mines. It is estimated that there are about five thousand five hundred of these. There is no legal liability to any party attached to abandoned metal mines in the UK if they ceased operation before 1999. Preventing pollution from entering river catchments from these sources can be expensive and public funds are limited in extent. These enduring sources of pollution are a significant impediment to compliance with the legislative requirements, such as the European Water Framework Directive. This thesis develops a framework for integrating pre-existing tools and methodologies to address this environmental problem: Environmental Impact Assessment (EIA), Life Cycle Impact Assessment (LCIA) and Payments for Ecosystem Services (PES). By fully quantifying the economic, social and environmental impacts of abandoned mine discharges and the net benefits of potential management interventions over different scales, it is proposed that the framework can provide a sustainable way forward for identifying appropriate cost-effective remedial interventions, identify sources of funding for remediation to take place through PES, while at the same time being sensitive to stakeholder concerns. To determine the effectiveness of this framework two phases of research have been undertaken. The first was a series of interviews with a range of key stakeholders with relevant knowledge and expertise, targeting key concerns and conflicts that arise in managing legacy pollution. The second was to apply the framework to a specific mine-impacted catchment to determine the effectiveness of the framework and an optimal solution for that site. Key findings of stakeholder interviews revealed the general positive attitude towards PES-schemes also discrepancies in knowledge between different sectors. Industrial representatives emphasised the likely need for regulation to initiate such processes. The potentially important role of stewardship and conservation organisations as “ethical brokers” for such schemes was highlighted, given their expertise at communicating and managing a range of stakeholder opinions. The application of the framework to the Hebden Beck catchment in North Yorkshire found that multiple small scale passive remediation at affected locations would be an optimal solution. The full costs of such systems are outweighed by the potential ecosystem service benefits of metal removal from upland streams. Fundamental to the acceptability and sustainability of the remedial solution was the requirement for habitat offsetting to be incorporated into the proposed works.

Microorganisms, such as bacteria, fungi, viruses and protozoa, colonise the inner surfaces of drinking water pipes and form biofilms. Drinking water biofilms act to protect the microorganisms that they house from the harsh conditions that we impose such as disinfection. Biofilms are generally thought of as being detrimental in drinking water distribution systems; they can harbour pathogens that intermittently emerge at the tap and they can affect the aesthetics of drinking water. The formation and dissolution of biofilms are intricately linked with the flow conditions and therefore, if we are to manage biofilms in drinking water systems, then it is imperative that we understand the crucial role that hydrodynamics play. Thus, my thesis focuses on the growth of biofilms in drinking water under three distinct flow regimes: turbulent, transition and laminar, and under stagnant conditions, and reveals the role that hydrodynamics play in shaping biofilms in drinking water distribution systems. Not all bacteria are merely passive tracers in flow whose fate is governed by the physical flow alone. This thesis presents evidence that there might be key bacteria in aggregation in drinking water, whose biology acts to enhance the formation of multi-species biofilms. I explored that by testing the role that the Methylobacterium strain DSM 18358 played in the formation of biofilms on surfaces that starts with the formation of aggregates in the bulk water. I also explored whether the ability of this Methylobacterium strain to form aggregates was influenced by the flow regime. Ultimately, this research reveals whether the formation and structure of those aggregates in drinking water is influenced by the subtle interplay between biological and physical processes. Given that they are bacteria that can degrade various dangerous chlorine disinfection by-products I explored the role of the Methylobacterium strain DSM 18358 in the concentration of trihalomethanes in drinking water as these chlorine disinfection by-products can cause serious problems to human health when they occur at high concentrations in drinking water. Overall, I identified whether the presence of this Methylobacterium strain in drinking water can actually deliver a service that contributes to better drinking water quality.

Assessing water quality is of crucial importance to both society and the environment. Deterioration in water quality through issues such as eutrophication presents substantial risk to human health, plant and animal life, and can have detrimental effects on the local economy. Long-term data records across multiple sites can be used to investigate water quality and risk factors statistically, however, identification of underlying changes can only be successful if there is a sufficient quantity of data available. As vast amounts of resources are required for the implementation and maintenance of a monitoring network, logistically and financially it is not possible to employ continuous monitoring of all water environments. This raises the question as to the optimal design for long-term monitoring networks which are capable of capturing underlying changes. Two of the main design considerations are clearly where to sample, and how frequently to sample. The principal aim of this thesis is to use statistical analysis to investigate frequently used environmental monitoring networks, developing new methodology where appropriate, so that the design and implementation of future networks can be made as effective and cost efficient as possible. Using data which have been provided by the Scottish Environment Protection Agency, several data from Scottish lakes and rivers and a range of determinands are considered in order to explore water quality monitoring in Scotland. Chapter 1 provides an introduction to environmental monitoring and both existing statistical techniques, and potential challenges which are commonly encountered in the analysis of environmental data are discussed. Following this, Chapter 2 presents a simulation study which has been designed and implemented in order to evaluate the nature and statistical power for commonly used environmental sampling and monitoring designs for surface waters. The aim is to answer questions regarding how many samples to base the chemical classification of standing waters, and how appropriate the currently available data in Scotland are for detecting trends and seasonality. The simulation study was constructed to investigate the ability to detect the different underlying features of the data under several different sampling conditions. After the assessment of how often sampling is required to detect change, the remainder of the thesis will attempt to address some of the questions associated with where the optimal sampling locations are. The European Union Water Framework Directive (WFD) was introduced in 2003 to set compliance standards for all water bodies across Europe, with an aim to prevent deterioration, and ensure all sites reach `good' status by 2015. One of the features of the WFD is that water bodies can be grouped together and the classification of all members of the group is then based on the classification of a single representative site. The potential misclassification of sites means one of the key areas of interest is how well the existing groups used by SEPA for classification capture differences between the sites in terms of several chemical determinands. This will be explored in Chapter 3 where a functional data analysis approach will be taken in order to investigate some of the features of the existing groupings. An investigation of the effect of temporal autocorrelation on our ability to distinguish groups of sites from one another will also be presented here. It is also of interest to explore whether fewer, or indeed more groups would be optimal in order to accurately represent the trends and variability in the water quality parameters. Different statistical approaches for grouping standing waters will be presented in Chapter 4, where the question of how many groups is statistically optimal is also addressed. As in Chapter 3, these approaches for grouping sites will be based on functional data in order to include the temporal dynamics of the variable of interest within any analysis of group structure obtained. Both hierarchical and model based functional clustering are considered here. The idea of functional clustering is also extended to the multivariate setting, thus enabling information from several determinands of interest to be used within formation of groups. This is something which is of particular importance in view of the fact that the WFD classification encompasses a range of different determinands. In addition to the investigation of standing waters, an entirely different type of water quality monitoring network is considered in Chapter 5. While standing waters are assumed to be spatially independent of one another there are several situations where this assumption is not appropriate and where spatial correlation between locations needs to be accounted for. Further developments of the functional clustering methods explored in Chapter 4 are presented here in order to obtain groups of stations that are not only similar in terms of mean levels and temporal patterns of the determinand of interest, but which are also spatially homogenous. The river network data explored in Chapter 5 introduces a set of new challenges when considering functional clustering that go beyond the inclusion of Euclidean distance based spatial correlation. Existing methodology for estimating spatial correlation are combined with functional clustering approaches and developed to be suitable for application on sites which lie along a river network. The final chapter of this thesis provides a summary of the work presented and discussion of limitations and suggestions for future directions.

This study deals with the ecology of ciliate and bacterial populations in operational slow sand filter beds used as a stage in treatment of river water for drinking water supply. It differs from earlier research in this college on the meiofauna and protozoa of similar filter beds in the source of water, the use of micro-strainers for pre-treatment, the coarser composition of the sand and in the study of bacteria. Three beds were studied but only one of these was studied for 9 runs, starting immediately after resanding in March 1985 and finishing in December 1985. The other beds were investigated comparatively to assess the effects of excluding sunlight. The sampling programme was designed to provide a time-course of depth distribution of densities of the ciliate protozoan and bacterial populations as well as the abundance of particulate organic carbon and chlorophyll a in relation to measures of the bed's performance such as head loss and filtration rates, which were monitored by Thames Water. Fourteen species of Ciliatea were commonly recorded and were counted alive after extraction from the sand at different depths and cold sedimentation. The same depths were used to determine the concentration of particulate organic carbon and chlorophyll a as well as the density of bacteria shaken off the sand grains and counted by incidence epifluorescence microscopy. As only single cores were taken on each sampling occasion due to the need to sample frequently, at many depths and to count live organisms, a special study was undertaken to estimate the horizontal variability of protozoan and bacterial densities. Tests were made on the extraction efficiency ofthe protozoan and bacterial techniques. Scanning electron microscopyof the sand grain surfaces from different depths was used to determine the sizes and shapes of the bacterial forms present as well as to assess the efficiency of the shaking technique for their removal. Thelinear dimensions of the different ciliate species were also measured. This permitted the calculation of cell volume of each common species, using formulae for the most appropriate geometric shape. Three phases of development in ciliate depth distributions occurred in most runs: during the first four days, ciliate densitieswere low and uniform throughout the depths; this was followed by increased densities in the top few cms and a sharp decline with depth; after the third week of the run, a marked surface avoidance was observed. The bacterial populations and the concentrations of POC and chlorophyll a showed similar patterns of depth distribution with time, with the exception of the phase with surface avoidance. The bed exposed to normal levels of sunlight was more productive than the other covered beds which was shown by the bacteria, ciliates, chlorophyll a and POC. Peak ciliate densities occurred during the third week of a run in all three beds but the highest bacterial densities appeared earlier (13-14 days) in the unshaded bed compared with the shaded ones (31 days). In all three beds, a marked decline in ciliate densities coincided with an increased development of the bacterial populations. During the first ten days of a run when head loss increased slowly, the ciliate and bacterial populations were able to increase their densities exponentially accompanied by an increasing cumulation of POC and chlorophyll a. This was followed by a period when the head loss increased more markedly when the ciliates, bacteria and chlorophyll a concentrations respond in a variety of ways in different runs but the POC continued to cumulate until the end of the run. These changes were accompanied by a succession in the species of ciliate which was numerically dominant and there was a change-over from predominantly bacterivore to carnivore forms. Scanning electron-micrographs of the sand grain surfaces showed that the bacteria were attached by strong filaments and that apparently anaerobic fusiform bacteria appeared towards the end of a run and during periods of high temperature. The micrographs were also used to assess the efficiency of the shaking technique at removing bacteria from the sand grain surfaces. A laboratory filter model was used to perturb experimentally the simulated sand filter system by changing the filtration rates experimentally and determining the depth distributions of the ciliate fauna and bacterial flora. In general, the densities of organisms in the model filter were less than those found in lit operational beds,perhaps because of the difficulty of provding realistic levels of radiation.

Although boron is an essential micronutrient for some plants, animals and humans, the range between deficiency and excess is narrow. The effects of excess boron on plants includes the reduction of root cell division, retarded shoot and root growth, inhibition of photosynthesis, deposition of lignin and suberin and decrease in leaf chlorophyll. A report by the World Health Organization (WHO) suggests a safe maximum level of boron daily intake of 13 mg/d an excessive level of boron can be toxic to and can causes serious diseases. There are several methods applied for boron removal from aqueous solutions and seawater. Among these methods, ion exchange, which is the most extensively method. Ion-exchange and adsorption are widely used techniques to remove metals and other solutes from aqueous solutions. This includes the removal of boron from reverse osmosis (RO) permeate in the process of seawater desalination. The use of boron-selective ion exchange resins based on macroporous polystyrene matrices with the active group N-methyl-D-glucamine (NMG) seems to still have the highest importance for the elimination of boron. Kinetics of adsorption or IEX is in many cases strongly influenced by diffusion resistance in particles of adsorbent. This resistance can be decreased by using smaller particles. Sorbents can be used as very fine particles which results in increase of the surface area and the process rate, considerably. Hybrid adsorption membrane filtration has gained the interest lately as it can be used for the removal of very small quantities of harmful substances from water. This thesis deals used hybrid system on both lab and pilot scale where a pilot plant was designed for the removal of boron. Boron separation combines two phenomena: i) sorption with fine sorbent particles and ii) membrane separation of B-loaded macromolecules/particles. The hybrid system includes two separation loops. Loop 1: Binding of boron (B) on Amberlite IRA743 resin (S), which is subsequently followed by separation of this (BS) complex from the water by means of semi-permeable microfiltration membrane. Here, pure water (W) is the main product whereas the complex (BS) passes to the second stage of separation. The effects of different parameters on boron removal using Amberlite IRA743 resin were investigated in this thesis. These parameters are, resin particle size, solution pH, temperature, contact time, initial boron concentration, resin concentration and the existence of different salts and ions like NaCl, Na2SO4 and MgCl2. The removal increased with increasing pH, temperature, contact time and resin dosage while it decreased with increasing initial boron concentration and resin particle size. For the microfiltration stage, three Polyvinylidene fluoride (PVDF) with different pore size have been used in this thesis. The effects of operational parameters like membrane pore size, transmembrane pressure, resin concentration and pH on permeate flux for hybrid adsorption-microfiltration were studied. The permeate flux increased with increasing the transmembrane pressure and pH but it decreased with increasing the resin concentration. The regeneration of loaded resin with boron was investigated. Hydrochloric acid (HCl) and sulfuric acid (H2SO4) at different concentrations have been used for the elution of boron from the saturated resin and then washing with sodium hydroxide (NaOH). There was an improvement in the boron removal after cycles of regeneration. The integrated adsorption-microfiltration was applied for boron removal from water and encouraging results were achieved.

Legacy industrial contaminants, such as trichloroethene (TCE), that have been released to aquifers in the last century, now threaten the quality of groundwater baseflow to lowland rivers and streams. Before reaching these receptors, contaminant plumes must first transit the heterogeneous environment of the aquifer-river interface. This research investigates the fate and potential for in-situ natural attenuation at this interface where a poorly-defined TCE plume potentially threatens a ‘gaining’ lowland river in the UK. It was possible to reveal a well-defined discharge zone of the plume in the riverbed with limited dispersion occurring in the low-permeability floodplain deposits. Through electrical resistivity imaging and intrusive sampling, this alluvial aquitard was revealed to be laterally extensive along the river corridor. A dissolved TCE flux of 0.43–1.5 g d–1 to the river was estimated,with most of this discharge occurring over a 40 m long reach, centred on a meander bend in the floodplain. The location and magnitude of this flux is influenced by continuity of stratified silt and peat deposits extending riverward from the floodplain, which provide significant retardation capacity. Metre-scale heterogeneity in the spatial variability of the groundwater discharge through these deposits was revealed with riverbed temperature mapping. A dominance of aerobic and nitrate-rich water throughout the aquifer-river system maintains a large stoichiometric demand for organic carbon and prevents the onset of reducing conditions required for significant dechlorination of the plume. However, at discrete shallow locations in the riverbed and parts of the alluvium, partial dechlorination of the plume was observed. A grid of pore water samplers revealed more enhanced dechlorination to cis-1,2-dichloroethene and vinyl chloride in methanogenic zones of the shallow sediment that was influenced by river macrophyte growth. Although in-situ natural attenuation does exceed the up-gradient aquifer in places, overall these processes are unlikely to prevent migration of the majority of the contaminant mass to the river. However, surface water impacts from this particular plume are unlikely with the large dilution available in the river itself.

Ce travail fait partie d'un grand projet pour la mise en œuvre d'un réseau urbain intelligent sur le Campus de la Cité Scientifique qui est équivalent à une petite ville d'environ 25000 habitants. Le réseau intelligent comprend (i) la mise en œuvre d’une instrumentation pour le suivi en temps réel et le contrôle du réseau de distribution d'eau et (ii) le développement d'un système expert basé sur l'expérience développée par l'industrie de l'eau ainsi que sur des recherches fondamentales et appliquées pour la gestion optimale des systèmes complexes. L'un des enjeux majeurs de ce système concerne la gestion de la demande en eau. Ce travail a porté sur cette question. Il comporte une synthèse bibliographique et l'analyse de la consommation d'eau du Campus Scientifique. Le travail est organisé en trois parties. La première partie présente une analyse bibliographique des recherches sur la demande d'eau, la localisation des fuites d’eau et le développement des réseaux intelligents dans le secteur de l’eau. Des études de cas sont présentées pour illustrer l'application des innovations dans des projets réels. La deuxième partie concerne la présentation du site du Campus, qui est utilisé dans ce travail de recherche. Ce site présente plusieurs avantages pour l'analyse de la demande en eau. Les bâtiments ont des usages variés: résidence, restauration, sport, administration, recherche, enseignement et enseignement / recherche. Le site est également équipé d'un système de télérelève (AMR). Les données de consommation sont disponibles pour les principaux bâtiments à différentes échelles de temps. La dernière partie présente une analyse de la consommation d'eau des principaux secteurs du campus, qui couvrent les différents usages des bâtiments. L'analyse est menée à différentes échelles de temps: mensuelle, hebdomadaire, journalière et horaire. Il débouche sur l'établissement de profils de consommation des principaux bâtiments, qui seront ensuite intégrés dans le système intelligent de gestion de l’eau. / This work is a part of a large project for the implementation of a smart water system in the Scientific Campus, which is equivalent to a small city with about 25 000 inhabitants. The smart water technology includes (i) the implementation of a real-time monitoring and control of the water distribution system and (ii) the development of an expert system based on the experience developed by the water industry as well as basic and applied researches for the optimal management of complex systems. One of the major issues in this system concerns the water demand management. This work concerned this issue. It included a literature survey and analysis of the water consumption in the Scientific Campus. The work includes three parts. The first part presents a literature analysis of researches ion the water demand, leakage localization and water smart grid. Case studies are presented for the illustration of the implementation of the latest technology and innovations in real projects. The second part concerns the presentation of the site of the Scientific Campus, which is used in this research work. This site presents several advantages for the analysis of the water demand. The buildings have varied usages: students’ residence, restaurant, sport, administration, research, teaching and teaching/research. The site is also equipped by an automatic metering reading (AMR). The consumption data is available for the main buildings at different time scales. The last part presents analysis of the water consumption of the main sectors of the Scientific Campus, which cover different buildings uses: research, teaching, administration, residence and catering. Analysis is conducted at different times scales: monthly, weekly, daily and hourly. It results in establishing consumption profile of the main buildings, which will then be integrated in the smart water system of the Campus.

La pénurie d'eau et l'augmentation de la demande en eau, en particulier pour un usage résidentiel sont les principaux défis auxquels sont confrontés la Palestine. La nécessité de prévoir avec précision la consommation d'eau est utile pour la planification et la gestion de cette ressource naturelle. L'objectif principal de cette recherche est de (i) étudier les principaux facteurs qui influent la consommation d'eau en Palestine, (ii) de comprendre le schéma général de la consommation d'eau des ménages, (iii) d'évaluer les éventuels changements dans la consommation d'eau des ménages et de proposer des solutions appropriées et (iv) élaborer un modèle de prédiction de la consommation d'eau dans les villes palestiniennes basé sur le Réseau de Neurones Artificiels.Le travail de recherche est organisé en quatre parties. La première partie comprend une analyse bibliographique des travaux réalisés sur la consommation d'eau des ménages. La deuxième partie concerne la collecte de données, la méthodologie, l’enquête sur la consommation d'eau des ménages et le traitement de données. La troisième partie présente une analyse statistique des données de consommation d'eau dans deux villes palestiniennes. La dernière partie développe la modélisation de la consommation d'eau dans les deux villes à l’aide des Réseaux de Neurones Artificiels. / Water scarcity and increasing water demand especially for residential use are major challenges facing Palestine. The need to accurately forecast water consumption is useful for the planning and management of this natural resource. The main objective of this research is to (i) study the major factors influencing the water consumption in Palestine, (ii) understand the general pattern of Household water consumption, (iii) assess the possible changes in household water consumption and suggest appropriate remedies and (iv) develop prediction model based on the Artificial Neural Network to the water consumption in Palestinian cities.The research is organized in four parts. The first part includes literature review of household water consumption studies. The second part concerns data collection methodology, conceptual framework for the household water consumption surveys, survey descriptions and data processing methods. The third part presents descriptive statistics, multiple regression and analysis of the water consumption in the two Palestinian cities. The final part develops the use of Artificial Neural Network for modeling the water consumption in Palestinian cities.