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This paper reports a simple, facile and rapid preparation of 3‑mercapto‑propanoic acid (MPA) modified cellulose filter paper (MPA-Cell paper) for arsenate removal from drinking water. The MPA was covalently grafted to the cellulose filter paper (Cell) by esterification process through the formation of O‑acylisourea intermediate and characterized by the FTIR, SEM, EDS and XPS analyses. The arsenate adsorption efficiency was studied for batch and semi-continuous systems while exploring the adsorption kinetics, isotherm and the effect of pH for the former. The experimental data fitted well with Langmuir, Dubinin-Radushkevich (DR) and pseudo second order kinetic models. The mechanism of adsorption was studied by FTIR spectroscopy utilizing the adsorption isotherm, kinetic model and XPS results. The modified filter paper performed well at nearly neutral pH in arsenate removal through adsorption and demonstrated a significant arsenate uptake capacity of 92.59 mg/g. The DR and FTIR results indicated that the adsorption of arsenate ion occurred through ion exchange process. The MPA-Cell paper could have a potential use as low-cost but efficient commercial adsorbent for arsenate abatement from contaminated drinking water by both batch as well as semi-continuous operating systems. The MPA-Cell paper could purify ground water containing high level of arsenate.

A study about the influence of polyaxial (true-triaxial) stresses on the permeability of a three-dimensional (3D) fractured rock layer is presented. The 3D fracture system is constructed by extruding a two-dimensional (2D) outcrop pattern of a limestone bed that exhibits a ladder structure consisting of a “through-going” joint set abutted by later-stage short fractures. Geomechanical behaviour of the 3D fractured rock in response to in-situ stresses is modelled by the finite-discrete element method, which can capture the deformation of matrix blocks, variation of stress fields, reactivation of pre-existing rough fractures and propagation of new cracks. A series of numerical simulations is designed to load the fractured rock using various polyaxial in-situ stresses and the stress-dependent flow properties are further calculated. The fractured layer tends to exhibit stronger flow localisation and higher equivalent permeability as the far-field stress ratio is increased and the stress field is rotated such that fractures are preferentially oriented for shearing. The shear dilation of pre-existing fractures has dominant effects on flow localisation in the system, while the propagation of new fractures has minor impacts. The role of the overburden stress suggests that the conventional 2D analysis that neglects the effect of the out-of-plane stress (perpendicular to the bedding interface) may provide indicative approximations but not fully capture the polyaxial stress-dependent fracture network behaviour. The results of this study have important implications for understanding the heterogeneous flow of geological fluids (e.g. groundwater, petroleum) in subsurface and upscaling permeability for large-scale assessments., Hydrogeology Journal, 25 (8), ISSN:1431-2174, ISSN:1435-0157

In this study, four ten years test areas with covered tailings were geochemically evaluated. Three areas were covered with a fly ash and an overlying sludge layer, and one only with a sludge cover, originating from paper mills. The accumulation of As, Fe and Pb in sludge layers, originating from air-borne dust and the depletion of K, Na and P from both cover layers were observed. High release of elements from tailings was observed in the comparison profile due to oxidation and weathering of tailings. In only sludge covered area, the leaching of elements from tailings decreased. In the profiles with thin ash (20 cm and 30 cm), most elements were retained in tailings with pH 7–9. In the profile with the thickest ash (50 cm), elements such as As, Cd, Cu, Mg, Mn, Pb, S and Zn were depleted in the uppermost tailings with pH above 11 and retained deeper in the zone with pH 7–8, which implied that large quantities of fly ash increased the oxidation and weathering of tailings and mobility of elements. Elements excluding K, never reached the groundwater in high concentrations in the covered areas, while the comparison area had high Ca, K, Mn and S concentrations.

Groundwater resources are important sources of drinking water in Africa, and they are hugely important in sustaining urban livelihoods and supporting a diverse range of commercial and agricultural activities. Groundwater has an important role in improving health in sub-Saharan Africa (SSA). An estimated 250 million people (40% of the total) live in urban centres across SSA. SSA has experienced a rapid expansion in urban populations since the 1950s, with increased population densities as well as expanding geographical coverage. Estimates suggest that the urban population in SSA will double between 2000 and 2030. The quality status of shallow urban groundwater resources is often very poor due to inadequate waste management and source protection, and poses a significant health risk to users, while deeper borehole sources often provide an important source of good quality drinking water. Given the growth in future demand from this finite resource, as well as potential changes in future climate in this region, a detailed understanding of both water quantity and quality is required to use this resource sustainably. This paper provides a comprehensive assessment of the water quality status, both microbial and chemical, of urban groundwater in SSA across a range of hydrogeological terrains and different groundwater point types. Lower storage basement terrains, which underlie a significant proportion of urban centres in SSA, are particularly vulnerable to contamination. The relationship between mean nitrate concentration and intrinsic aquifer pollution risk is assessed for urban centres across SSA. Current knowledge gaps are identified and future research needs highlighted.Les ressources en eaux souterraines sont des sources importantes d’eau potable en Afrique, et elles sont d’une énorme importance pour les êtres vivants en milieu urbain et pour le soutien d’une gamme diversifiée d’activités commerciales et agricoles. Les eaux souterraines jouent un rôle important en améliorant la santé en Afrique sub-saharienne (ASS). 250 millions de personnes environ (40% du total) vivent dans des centres urbains à travers l’ASS. L’ASS a connu une expansion rapide de ses populations urbaines depuis les années 1950, avec une augmentation à la fois des densités de population et de leur extension géographique. Les estimations prévoient un doublement de la population urbaine de l’ASS entre 2000 et 2030. L’état qualitatif des ressources en eau souterraine urbaines peu profondes est souvent très pauvre du fait de l’insuffisance de la gestion des déchets et de la protection de la ressource, et pose un risque sanitaire significatif pour les utilisateurs, alors que des ressources plus profondes captées par forage fournissent souvent une source importante d’eau potable de bonne qualité. Etant donné la croissance de la demande future de cette ressource limitée, ainsi que le changement climatique potentiel dans cette région dans le futur, une compréhension détaillée de la quantité et la qualité de cette ressource est exigée pour son utilisation durable. Cet article fournit une évaluation complète de l’état qualitatif, à la fois microbien et chimique, des eaux souterraines urbaines en ASS à travers une gamme de contextes hydrogéologiques et de différents types de point d’eaux souterraines. Les terrains du sous-sol de faible emmagasinement, qui sont situés sous une proportion significative de centres urbains en ASS, sont particulièrement vulnérables à la contamination. Le rapport entre la concentration moyenne en nitrate et le risque intrinsèque de pollution des aquifères est évalué pour les centres urbains de l’ASS. Des lacunes actuelles en matière de connaissances sont identifiées et les besoins de recherches futurs sont mis en évidence.Los recursos hídricos subterráneos son una fuente importante de agua potable en África y son sumamente importantes para mantener los medios de subsistencia urbanos y para apoyar una amplia gama de actividades comerciales y agrícolas. El agua subterránea tiene un papel importante en la mejora de la salud en el África Subsahariana (SSA). Se calcula que 250 millones de personas (40% del total) viven en centros urbanos en el África Subsahariana. El SSA ha experimentado una rápida expansión en las poblaciones urbanas desde la década de 1950, con el aumento de la densidad de población, así como la ampliación de la cobertura geográfica. Las estimaciones sugieren que la población urbana en África Subsahariana se duplicará entre 2000 y 2030. El estado de calidad del agua subterránea somera es a menudo muy pobre debido a la gestión inadecuada de los desechos y de la protección de las fuentes, representando un riesgo significativo para los usuarios, mientras que los pozos más profundos proporcionan una fuente importante de agua potable de buena calidad. Dado el crecimiento de la demanda futura de este recurso finito, así como los cambios potenciales en el clima futuro en esta región, una comprensión detallada de su cantidad y calidad es necesaria para utilizar este recurso de manera sostenible. Este artículo ofrece una evaluación integral del estado de la calidad del agua, tanto microbiana como química, del agua subterránea urbana en el SSA a lo largo de una serie de terrenos hidrogeológicos y diferentes tipos de puntos de agua subterránea. Los basamentos de bajo almacenamiento, que subyacen a una proporción significativa de los centros urbanos del África Subsahariana, son particularmente vulnerables a la contaminación. Se evalúa la relación entre la concentración media de nitratos y el riesgo intrínseco de contaminación acuífera para los centros urbanos a través de la SSA. Se identifican las deficiencias actuales de conocimientos y se destacan las necesidades de futuras investigaciones.地下水资源是非洲重要的饮用水源,在维系城市生计和支撑各种商业和农业活动中至关重要。地下水在改善撒哈拉以南非洲民众健康方面发挥着重要作用。在撒哈拉以南非洲,预计有2.5亿人居住在城市地区(占总数的40 %)。自从上世纪50年代,本区域城市人口快速膨胀,密度不断增加,面积不断扩大。估测结果显示,撒哈拉以南非洲的城市人口在2000年至2030年间将翻一番。由于废物管理不当及水源污染,城市浅层地下水源水质常常非常差,对用水者产生很大的健康风险,而较深钻井水源常常提供重要的高质量饮水水源。考虑到此有限水源的基础上将来需求的增长以及本地区将来的气候潜在变化,需要详细了解水量和水质状况,以便可持续利用水源。本文从微生物和化学上综合评价了撒哈拉以南非洲各种水质状况地形及不同地下水水点类型的水质状况。在撒哈拉以南非洲,水存储量低的基岩地形在城市中心占有很大的比例,特别容易受到污染。对整个撒哈拉以南非洲的城市中心平均硝酸盐含量和固有的含水层污染风险之间的关系进行了评价。明确了目前的认识空白,并强调了将来的研究需求。.As águas subterrâneas são fontes importantes de água para consumo na África, e são amplamente importantes para sustentar o modo de vida urbano e dar suporte a uma amplitude diversa de atividades comerciais e agrícolas. As águas subterrâneas têm um papel importante no desenvolvimento da saúde na África subsaariana (ASS). São estimadas 250 milhões de pessoas (40% do total) vivendo nos centros urbanos na ASS. ASS tem vivenciado uma rápida expansão na população urbana desde os anos 50, com aumento das densidades populacionais assim como expansão da cobertura geográfica. As estimativas sugerem que a população urbana na ASS dobrará entre 2000 e 2030. As condições de qualidade dos aquíferos livres em áreas urbanas estão frequentemente muito pobres por causa do gerenciamento de perdas e proteção das fontes inadequados, e apresenta um risco significativo à saúde dos usuários, enquanto poços mais profundos frequentemente fornecem fontes importantes de água potável de boa qualidade. Dado o crescimento na demanda futura desse recurso finito, assim como mudanças potenciais no clima futuro da região, um entendimento detalhado da sua quantidade e qualidade é necessário para o uso sustentável deste recurso. Esse estudo fornece uma avaliação compreensiva das condições de qualidade da água, tanto microbiológica quanto química, das águas subterrâneas urbanas na ASS por uma gama de terrenos hidrogeológicos e diferentes tipos pontuais de águas subterrâneas. Terrenos de menor armazenamento de base, que fundamentam uma porção significante dos centros urbanos da ASS, são particularmente vulneráveis a contaminação. A relação entre a concentração média de nitrato e o risco intrínseco de poluição do aquífero é avaliado para os centros urbanos na ASS. Lacunas do conhecimento atual foram identificadas e destaca-se a necessidade de pesquisas futuras.

This report is a synthesis of the technical assistance (TA) and recommendations, carried out by the World Bank water and sanitation program (WSP) since September 2014. To achieve the target of 100 percent improved sanitation, there is a national drive to improve fecal sludge management (FSM). This TA recognizes that to achieve the goals it is necessary to support the development of national FSM policies, regulations, and guidelines, while also improving capacity at the local level by supporting the implementation of improved FSM models in target cities. The objective of the TA was to provide government with tested advice on how to scale up improved septage management nationwide through: (i) improvement of septage management in three cities through the application of new management models (local level); and (ii) assistance to national government in training and capacity building and the formulation of policies and regulations to improve septage management at scale (national level). This report is structured as follows: chapter one is the executive summary; chapter two gives the background to sanitation in Indonesia and to fecal sludge management in particular; chapter three provides an overview of the TA approach; chapter four gives details of the implementation of the TA; chapter five summarizes the lessons learned; and chapter six outlines the recommendations and next steps.

This synthesis report details the process, outputs and intermediate outcomes of the World Bank’s Water and Sanitation Program (WSP) Technical Assistance (TA) to Support Government of India for implementation of the National Urban Sanitation Policy (P131963). The objective of this TA was to (i) strengthen urban sanitation services and target the urban poor by development of strategies for regulation, funds allocation, improved accountability mechanisms and implementation of inclusive sanitation policies at national level and in at least five states, with two of these low-income states (LIS). This was to be supplemented with (ii) enabling design and use of improved performance monitoring systems by Government of India, 3 states and 300 urban local bodies by 2015, and (iii) strengthen capacity of local urban government institutions to provide improved – inclusive and sustainable – sanitation services for all. This TA provides the building blocks for sustainable sanitation improvements which are being adopted and implemented as part of another TA (P131967) in Madhya Pradesh and Tripura to pilot and operationalize City Sanitation Plans (CSPs) towards outcome oriented sector improvements. The areas addressed in this TA include the following specific goals of the NUSP: open defecation free cities, and integrated city-wide sanitation. The TA provided assistance to central government and the states in putting in place various elements identified as necessary for sector improvement, including planning, provisioning and monitoring processes. The TA also identified the need for the cities to see opportunities for financial recovery of investments through reuse and recycle strategies, to strengthen the incentive for investment in sanitation improvements.

13C NMR analyses of hydrophobic dissolved organic matter (DOM) fractions isolated from a landfill leachate contaminated groundwater near Norman, OK; the Colorado River aqueduct near Los Angeles, CA; Anaheim Lake, an infiltration basin for the Santa Ana River in Orange County, CA; and groundwater from the Tomago Sand Beds, near Sydney, Australia, found branched methyl groups and quaternary aliphatic carbon structures that are indicative of terpenoid hydrocarbon precursors. Significant amounts of lignin precursors, commonly postulated to be the major source of DOM, were found only in trace quantities by thermochemolysis/gas chromatography/mass spectrometry of the Norman Landfill and Tomago Sand Bed hydrophobic DOM fractions. Electrospray/tandem mass spectrometry of the Tomago Sand Bed hydrophobic acid DOM found an ion series differing by 14 daltons, which is indicative of aliphatic and aryl-aliphatic polycarboxylic acids. The product obtained from ozonation of the resin acid, abietic acid, gave a similar ion series. Terpenoid precursors of DOM are postulated to be derived from resin acid paper sizing agents in the Norman Landfill, algal and bacterial terpenoids in the Colorado River and Anaheim Lake, and terrestrial plant terpenoids in the Tomago Sand Beds.

Aim To assess the level of 15 groundwater quality parameters in groundwater samples collected around municipal landfill and paper factory in order to evaluate usefulness of the groundwater and its possible implication on the human health. Methods Obtained data have been analyzed by principal component analysis (PCA) technique, in order to differentiate the groundwater samples on the basis of their compositional differences and origin. Results Wastes and effluents from municipal landfill did not contribute significantly to the pollution of the aquatic medium. Groundwater degradation caused by high contents of nitrate, mineral oils, organic and inorganic matters was particularly expressed in the narrow area of the city centre, near the paper factory and most likely it has occurred over a long period of time. The results have shown that the concentrations of the most measured parameters(NO3-N, NH4-N, oils, organic matter, Fe, Pb, Ni and Cr) were above llowed limits for drinking and domestic purposes. onclusion This study has provided important information on cological status of the groundwater systems and for identification f groundwater quality parameters with concentrations above llowable limits for human consumption. The results generally evealed that groundwater assessed in this study mainly does not atisfy safe limits for drinking water and domestic use. As a consequence, ontaminated groundwater becomes a large hygienic nd toxicological problem, since it considerably impedes groundwater tilization. Even though, all of these contaminants havenot yet reached toxic levels, they still represent long term risk for ealth of the population.

For a hardcopy of this article, printed in the Netherlands, an estimated 100 l of water have been used. Most of the water is required in the forestry stage, due to evapotranspiration (green and blue water). In addition, the water footprint during the industrial stage, as accounted for in this study, consists of evaporation from water obtained from ground water and surface water (blue water). In this study estimates are made of water requirements for producing paper using different types of wood and in different parts of the world. The water footprint of printing and writing paper is estimated to be between 300 and 2600 m3/t (~2-13 l for an A4 sheet). These estimates account for paper recovery rates in different countries. This study indicates that by using recovered paper for the production of paper the global average water footprint of paper is only 60% of what it would be if no recovered paper would be used at all. Further savings may be achieved by increasing the recovery percentages worldwide. In addition, the global water footprint of paper can be reduced by choosing production sites and wood types that are more water-efficient. The results of this study suggest that the use of recovered paper may be particularly effective in reducing water footprints. This study is a first step towards a better understanding of the significance of the water footprint of paper and the effect of using recovered paper.

Subsidence of organic soils in the Sacramento-San Joaquin Delta threatens sustainability of the California (USA) water supply system and agriculture. Land-surface elevation data were collected to assess present-day subsidence rates and evaluate rice as a land use for subsidence mitigation. To depict Delta-wide present-day rates of subsidence, the previously developed SUBCALC model was refined and calibrated using recent data for COL’affaissement des sols organiques dans le Delta de Sacramento-San Joaquin menace la durabilité du système d’approvisionnement en eau et de l’agriculture de la Californie (Etats-Unis d’Amérique). Des données d’altitude de la surface topographique ont été collectées dans le but d’estimer le taux d’affaissement actuel des sols et d’évaluer l’occupation des sols par des rizières en tant que moyen d’atténuation de l’affaissement des sols. Pour décrire les taux actuels d’affaissement des sols à l’échelle du Delta, le modèle SUBCALC développé précédemment a été affiné et calé grâce à l’utilisation des données récentes sur les émissions de COLa subsidencia de los suelos orgánicos en el Delta de Sacramento-San Joaquín amenaza la sostenibilidad del sistema de suministro de agua y la agricultura en California (EE.UU.). Se recolectaron datos de elevación de la superficie del terreno para evaluar las tasas de subsidencia actuales y evaluar el cultivo de arroz como un uso de la tierra para la mitigación de la subsidencia. Se refinó y calibró el modelo SUBCALC desarrollado previamente para describir las tasas de la subsidencia en el ancho actual del Delta, usando los datos más recientes de las emisiones de CO沙加缅度河—圣华金河三角洲有机土壤的下沉威胁着(美国)加利佛尼亚州供水系统和农业的可持续性。收集了地面高程资料以评价目前的下沉速率并且评估了土地种植水稻减缓下沉的作用。为了描述三角洲范围内目前的下沉速度,采用目前的COA subsidência dos organossolos no Delta dos rios Sacramento-San Joaquin põe em risco a sustentabilidade do sistema de abastecimento de água e da agricultura do estado da Califórnia (EUA). Foram coletados dados de elevação da superfície do solo para estimar as taxas atuais de subsidência e avaliar o uso de cultivo de arroz para mitigar a subsidência. Para simular as taxas atuais de subsidência da região do Delta, o modelo SUBCALC, desenvolvido anteriormente, foi refinado e calibrado utilizando dados recentes de emissões de CO