Geothermal characterization of the coastal aquifer near Ravenna (Italy

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M. Antonellini

2012-12-01

Full Text Available The coastal aquifer near Ravenna (Italy contains a large volume of groundwater (2,5x109 m3 whose quality has been compromised by sea-water intrusion. Today, the phreatic groundwater is mostly brackish with some lenses of freshwater floating on top of more saline water. This water, although impossible to use as drink-water or for irrigation, is still important to guarantee the health of wetland habitats and especially of the roman historical and coastal pine forests of Ravenna. With the objective of defining the flow pattern within the aquifer and the exchange between surface and ground water, we characterized the temperature distribution in the shallow subsurface by means of a dense network of piezometers. At the same time we had the opportunity to characterize the phreatic aquifer from the geothermal point of view, so that it could eventually be considered for use as a “low enthalpy” heat source. Heat pumps are able to extract heat during the winter and dissipate it during the summer. The temperature of the groundwater in the top layer of the aquifer (surficial zone is sensitive to the changes in atmospheric temperature throughout the year whereas the temperature of the deeper groundwater follows the geothermal gradient (geothermal zone. One of the scopes of the project is to discover at what depth is located the geothermal zone, so that the aquifer has a constant temperature throughout the year. A constant temperature is needed for storage of heat at low enthalpy. The thickness of the surficial zone and the temperature at the top of the geothermal zone are essentially related to land use, distance from the sea, sediment type, and amount of interaction between surface and groundwater. A knowledge of these factors allows to better exploit the geothermal potential of the aquifer when choosing the optimal placement of the heat pumps.

Closed-form analytical solutions incorporating pumping and tidal effects in various coastal aquifer systems

Science.gov (United States)

Wang, Chaoyue; Li, Hailong; Wan, Li; Wang, Xusheng; Jiang, Xiaowei

2014-07-01

Pumping wells are common in coastal aquifers affected by tides. Here we present analytical solutions of groundwater table or head variations during a constant rate pumping from a single, fully-penetrating well in coastal aquifer systems comprising an unconfined aquifer, a confined aquifer and semi-permeable layer between them. The unconfined aquifer terminates at the coastline (or river bank) and the other two layers extend under tidal water (sea or tidal river) for a certain distance L. Analytical solutions are derived for 11 reasonable combinations of different situations of the L-value (zero, finite, and infinite), of the middle layer's permeability (semi-permeable and impermeable), of the boundary condition at the aquifer's submarine terminal (Dirichlet describing direct connection with seawater and no-flow describing the existence of an impermeable capping), and of the tidal water body (sea and tidal river). Solutions are discussed with application examples in fitting field observations and parameter estimations.

Groundwater Flow Model of Göksu Delta Coastal Aquifer System

Science.gov (United States)

Erdem Dokuz, Uǧur; Çelik, Mehmet; Arslan, Şebnem; Engin, Hilal

2016-04-01

Like many other coastal areas, Göksu Delta (Mersin-Silifke, Southern Turkey) is a preferred place for human settlement especially due to its productive farmlands and water resources. The water dependent ecosystem in Göksu delta hosts about 332 different plant species and 328 different bird species besides serving for human use. Göksu Delta has been declared as Special Environmental Protection Zone, Wildlife Protection Area, and RAMSAR Convention for Wetlands of International Importance area. Unfortunately, rising population, agricultural and industrial activities cause degradation of water resources both by means of quality and quantity. This problem also exists for other wetlands around the world. It is necessary to prepare water management plans by taking global warming issues into account to protect water resources for next generations. To achieve this, the most efficient tool is to come up with groundwater management strategies by constructing groundwater flow models. By this aim, groundwater modeling studies were carried out for Göksu Delta coastal aquifer system. As a first and most important step in all groundwater modeling studies, geological and hydrogeological settings of the study area have been investigated. Göksu Delta, like many other deltaic environments, has a complex structure because it was formed with the sediments transported by Göksu River throughout the Quaternary period and shaped throughout the transgression-regression periods. Both due to this complex structure and the lack of observation wells penetrating deep enough to give an idea of the total thickness of the delta, it was impossible to reveal out the hydrogeological setting in a correct manner. Therefore, six wells were drilled to construct the conceptual hydrogeological model of Göksu Delta coastal aquifer system. On the basis of drilling studies and slug tests that were conducted along Göksu Delta, hydrostratigraphic units of the delta system have been obtained. According to

Global assessment of coastal aquifer state and its vulnerability respect to Sea Water Intrusion. Application to several Mediterranean Coastal Aquifers.

Science.gov (United States)

Baena, Leticia; Pulido-Velazquez, David; Renau-Pruñonosa, Arianna; Morell, Ignacio

2017-04-01

In this research we propose a method for a global assessment of coastal aquifer state and its vulnerability to Sea Water Intrusion (SWI). It is based on two indices, the MART index, which summarize the global significance of the SWI phenomenon, and the L_GALDIT for a lumped assessment of the vulnerability to SWI. Both of them can be useful as a tool to assess coastal groundwater bodies in risk of not achieving good status in accordance with the Water Framework Directive (WFD, 2000) and to identify possible management alternative to reduce existing impacts. They can be obtained even from a reduced number of data (in the MART case only depend on the geometry and available aquifer state data) with simple calculations, which have been implemented in a general GIS tool that can be easily applied to other case studies. The MART index in an aquifer is related with the total mass of chloride in the aquifer due to sea water intrusion and can be obtained by simple linear operations of volume and concentrations that can be deduced from a schematic conceptual cross-section approach (orthogonal to the shore line) defined to summarize the intrusion volume in the aquifer. At a certain historical time, this representative aquifer cross-section can be defined in a systhematic way from the aquifer geometry, the specific yield, and the hydraulic head and chloride concentration fields that can be deduced from the available information by using appropriate interpolation methods. Following the proposed procedure we will finally obtain a summary of the historical significance of the SWI in an aquifer at different spatial resolution: 3D salinity concentration maps, 2D representative conceptual cross-section of intrusion and the MART lumped significance index. The historical evolution of the MART can be employed to perform a global assessment of the resilience and trends of global significance of the SWI in an aquifer. It can be useful to compare the significance of intrusion problems in

Estimated hydrologic budgets of kettle-hole ponds in coastal aquifers of southeastern Massachusetts

Science.gov (United States)

Walter, Donald A.; Masterson, John P.

2011-01-01

Kettle-hole ponds in southeastern Massachusetts are in good hydraulic connection to an extensive coastal aquifer system that includes the Plymouth-Carver aquifer system on the mainland and aquifers underlying Cape Cod. The ponds receive water from, and contribute water to, the underlying glacial aquifer; ponds also receive water from precipitation and lose water to evaporation from the pond surface. Some ponds are connected to surface-water drainage systems and receive water from or contribute water to streams or adjacent wetlands. The Massachusetts Department of Environmental Protection currently (2011) is developing Total Maximum Daily Loads of phosphorus for the freshwater ponds in the region to maintain the health of pond ecosystems; the amounts and sources of water fluxes into and out of the ponds are important factors in determining the amount of phosphorus that can be assimilated into a pond. To assist in this effort, the U.S. Geological Survey used groundwater-flow models of the coastal aquifer system to estimate hydrologic budgets-including inflows and outflows from the aquifer system and adjacent streams and wetlands, and recharge from precipitation-for 425 ponds in southeastern Massachusetts.

Groundwater chemistry of shallow aquifers in the coastal zones of Cochin, India

Digital Repository Service at National Institute of Oceanography (India)

Laluraj, C.M.; Gopinath, G.; DineshKumar, P.K.

Laluraj et al.: Groundwater chemistry of shallow aquifers - 133 - APPLIED ECOLOGY AND ENVIRONMENTAL RESEARCH 3(1): 133-139. http://www.ecology.kee.hu ● ISSN 1589 1623  2005, Penkala Bt., Budapest, Hungary GROUNDWATER CHEMISTRY OF SHALLOW AQUIFERS... post monsoon (November 2003) in the coastal zones of Cochin. Laluraj et al.: Groundwater chemistry of shallow aquifers - 134 - APPLIED ECOLOGY AND ENVIRONMENTAL RESEARCH 3(1): 133-139. http://www.ecology.kee.hu ● ISSN 1589 1623  2005, Penkala...

A fuzzy multicriteria categorization of the GALDIT method to assess seawater intrusion vulnerability of coastal aquifers.

Science.gov (United States)

Kazakis, Nerantzis; Spiliotis, Mike; Voudouris, Konstantinos; Pliakas, Fotios-Konstantinos; Papadopoulos, Basil

2018-04-15

Groundwater constitutes the primary source of fresh water for >1.2 billion people living in coastal zones. However, the threat of seawater intrusion is widespread in coastal aquifers mainly due to overexploitation of groundwater. In the present study, a modified fuzzy multicriteria categorization into non-ordered categories method was developed in order to modify the standard GALDIT method and assess seawater intrusion vulnerability in a coastal aquifer of northern Greece. The method is based on six parameters: groundwater occurrence, aquifer hydraulic conductivity, groundwater level, distance from the shore, impact of the existing status of seawater intrusion, and aquifer thickness. Initially, the original method was applied and revealed a zone of high vulnerability running parallel to the coastline and covering an area of 8.6km 2 . The modified GALDIT-F method achieved higher discretization of vulnerability zones which is essential to build a rational management plan to prevent seawater intrusion. The GALDIT-F approach also distinguished an area of the aquifer that is influenced by geothermal fluids. In total, twenty-five categories were produced corresponding to different vulnerability degrees according to the initial method (High, Moderate, Low) as well as the area influenced by geothermal fluids. Finally, a road map was developed in order to adapt management strategies to GALDIT-F categories and prevent and mitigate seawater intrusion. The proposed management strategies of the coastal aquifer include managed aquifer recharge (MAR) implementation, reallocation of existing wells, optimization of pumping rates during the hydrological year, and a detailed monitoring plan. Copyright © 2017 Elsevier B.V. All rights reserved.

Groundwater salinity in coastal aquifer of Karachi, Pakistan

International Nuclear Information System (INIS)

Mashiatullah, A.; Qureshi, R.M.; Ahmad, E.; Tasneem, M.A.; Sajjad, M.I.; Khan, H.A.

2002-01-01

Potable groundwater salinity has become a problem of great concern in the Karachi Metropolis, which is not only the most populous and biggest industrial base but also the largest coastal dwelling of Pakistan. Stable isotope techniques [O/sup 18/ content of Oxygen in the water molecular and C/sup 13/ content of the Total Dissolved Inorganic Carbon (TDIC)] have been used, in conjunction with physiochemical tools (temperature, dissolved oxygen, pH, redox electrical conductivity, salinity), to examine the quality of potable water and the source of salinity. Surface water samples (12 No.) were collected from polluted streams, namely: Layeri River, Malir River; Hub River/Hub Lake and the Indus River. Shallow groundwater samples (7 No. ) were collected from operating dug wells. Relatively deep groundwater samples (12 No.) were collected from operating dug wells, relatively deep groundwater samples (12 No.) were collected from pumping wells/tube-wells. Physicochemical analysis of water samples was completed in the field. In the laboratory, water samples were analyzed for O/sup 18/ content of oxygen in the water molecule and C/sup 13/ content of the TDIC, using specific gas extraction systems and a modified GD-150 gas source mass spectrometer. It is concluded from this preliminary investigation that the potable aquifer system in coastal Karachi hosts a mixture of precipitation (rainwater only) from hinterlands, trapped seawater in relatively deep aquifer system, as well as intruded seawater under natural infiltration conditions and/or induced recharge conditions (in shallow aquifers). (author)

A correction for Dupuit-Forchheimer interface flow models of seawater intrusion in unconfined coastal aquifers

Science.gov (United States)

Koussis, Antonis D.; Mazi, Katerina; Riou, Fabien; Destouni, Georgia

2015-06-01

Interface flow models that use the Dupuit-Forchheimer (DF) approximation for assessing the freshwater lens and the seawater intrusion in coastal aquifers lack representation of the gap through which fresh groundwater discharges to the sea. In these models, the interface outcrops unrealistically at the same point as the free surface, is too shallow and intersects the aquifer base too far inland, thus overestimating an intruding seawater front. To correct this shortcoming of DF-type interface solutions for unconfined aquifers, we here adapt the outflow gap estimate of an analytical 2-D interface solution for infinitely thick aquifers to fit the 50%-salinity contour of variable-density solutions for finite-depth aquifers. We further improve the accuracy of the interface toe location predicted with depth-integrated DF interface solutions by ∼20% (relative to the 50%-salinity contour of variable-density solutions) by combining the outflow-gap adjusted aquifer depth at the sea with a transverse-dispersion adjusted density ratio (Pool and Carrera, 2011), appropriately modified for unconfined flow. The effectiveness of the combined correction is exemplified for two regional Mediterranean aquifers, the Israel Coastal and Nile Delta aquifers.

Analysis and Remediation of the Salinized, Damour Coastal (Dolomitic) Limestone Aquifer in Lebanon

NARCIS (Netherlands)

Khadra, W.M.

2017-01-01

Coastal aquifer management has recently emerged as a main scope in groundwater hydrology, especially in arid and semi-arid zones. About two thirds of the human population are currently gathered close to shorelines relying on coastal groundwater resources. Worldwide, these systems are subject to

Reactive dispersive contaminant transport in coastal aquifers: Numerical simulation of a reactive Henry problem

KAUST Repository

Nick, H.M.

2013-02-01

The reactive mixing between seawater and terrestrial water in coastal aquifers influences the water quality of submarine groundwater discharge. While these waters come into contact at the seawater groundwater interface by density driven flow, their chemical components dilute and react through dispersion. A larger interface and wider mixing zone may provide favorable conditions for the natural attenuation of contaminant plumes. It has been claimed that the extent of this mixing is controlled by both, porous media properties and flow conditions. In this study, the interplay between dispersion and reactive processes in coastal aquifers is investigated by means of numerical experiments. Particularly, the impact of dispersion coefficients, the velocity field induced by density driven flow and chemical component reactivities on reactive transport in such aquifers is studied. To do this, a hybrid finite-element finite-volume method and a reactive simulator are coupled, and model accuracy and applicability are assessed. A simple redox reaction is considered to describe the degradation of a contaminant which requires mixing of the contaminated groundwater and the seawater containing the terminal electron acceptor. The resulting degradation is observed for different scenarios considering different magnitudes of dispersion and chemical reactivity. Three reactive transport regimes are found: reaction controlled, reaction-dispersion controlled and dispersion controlled. Computational results suggest that the chemical components\\' reactivity as well as dispersion coefficients play a significant role on controlling reactive mixing zones and extent of contaminant removal in coastal aquifers. Further, our results confirm that the dilution index is a better alternative to the second central spatial moment of a plume to describe the mixing of reactive solutes in coastal aquifers. © 2012 Elsevier B.V.

Isotopes to Study the coastal aquifer plain, Cap Bon, Tunisia

International Nuclear Information System (INIS)

Ben Hamouda, M. F.; Zouari, Kamel; Tarhouni, J.; Gaye, C.B.; Oueslati, M.N.

2005-01-01

The study area is located in the northeastern part of Tunisia about 60 km south of the Tunis city. It is bounded by the Gulf of Haematite in the East, Djebel Sidi Aberahmane in the West, The town of Nabeul in the south and the area of the town Kelibia in the north. The landscape is a coastal plain slightly sloping (3%) towards the sea. The groundwater of the Oriental coast aquifer system occurs mainly at two levels, a shallow aquifer up to depths of about 50 m whose reservoir is consisted by sediments of the Plio quaternary and a deep aquifer between about 150 and 400 m located in the sand stone formations of Miocene of the anticline of Djebel Sidi Abderrahmene. The climate of the region is semi-arid to sub-humid and of Mediterranean type. There are no perennial rivers in this region; but intense storms occasionally cause surface runoff, which is discharged by the oueds. The study is related to a technical cooperation project with the International Atomic Energy Agency, Vienna, Austria, aimed at the use of isotope techniques to study the seawater intrusion into the coastal aquifers of Cap Bon in Tunisia. In this regard, a better understanding of the recharge and flow regime as well as the origin or salinity of the groundwater was required. To reach this goal, isotope and geochemical investigations were carried out. Water samples were taken from wells, boreholes from deep and shallow aquifer of the Oriental coastal aquifer located between Beni Khiar in the south and Kelibia in the north. The samples were analysed for their chemical and isotopic compositions (18O, 2H, 3H, 13C, 14C, 34S). In the following, the results of these analyses are presented and discussed in terms of the recharge and flow regime of the groundwater and the origin and evolution of its salinity. The results of geochemical and isotopic studies have shown that the groundwater is very eterogeneous and suggest the aquifer is replenished by recent water coming from direct infiltration from rain. At

Glacial recharge, salinisation and anthropogenic contamination in the coastal aquifers of Recife (Brazil)

Energy Technology Data Exchange (ETDEWEB)

Chatton, E., E-mail: eliot.chatton@gmail.com [Géosciences Rennes, Université Rennes 1-CNRS, UMR 6118, adress: 263 av du général Leclerc, Campus de Beaulieu, bat 15, 35042 Rennes Cedex (France); Aquilina, L., E-mail: luc.aquilina@univ-rennes1.fr [Géosciences Rennes, Université Rennes 1-CNRS, UMR 6118, adress: 263 av du général Leclerc, Campus de Beaulieu, bat 15, 35042 Rennes Cedex (France); Pételet-Giraud, E., E-mail: e.petelet@brgm.fr [Bureau de Recherches Géologiques et Minières (BRGM), adress: 3 avenue Claude-Guillemin, BP 36009, 45060 Orléans Cedex 2 (France); Cary, L., E-mail: l.cary@brgm.fr [Bureau de Recherches Géologiques et Minières (BRGM), adress: 3 avenue Claude-Guillemin, BP 36009, 45060 Orléans Cedex 2 (France); Bertrand, G., E-mail: guillaume353@gmail.com [Instituto de Geociências, CEPAS (Groundwater Research Center), University of São Paulo, adress: Rua do lago 562, 05508-080 Sao Paulo (Brazil); Labasque, T., E-mail: thierry.labasque@univ-rennes1.fr [Géosciences Rennes, Université Rennes 1-CNRS, UMR 6118, adress: 263 av du général Leclerc, Campus de Beaulieu, bat 15, 35042 Rennes Cedex (France); and others

2016-11-01

Implying large residence times and complex water origins deep coastal aquifers are of particular interest as they are remarkable markers of climate, water use and land use changes. Over the last decades, the Metropolitan Region of Recife (Brazil) went through extensive environmental changes increasing the pressure on water resources and giving rise to numerous environmental consequences on the coastal groundwater systems. We analysed the groundwater of the deep aquifers Cabo and Beberibe that are increasingly exploited. The processes potentially affecting groundwater residence times and flow paths have been studied using a multi-tracer approach (CFCs, SF6, noble gases, 14C, 2H and 18O). The main findings of these investigations show that: (1) Groundwaters of the Cabo and Beberibe aquifers have long residence times and were recharged about 20,000 years ago. (2) Within these old groundwaters we can find palaeo-climate evidences from the last glacial period at the tropics with lower temperatures and dryer conditions than the present climate. (3) Recently, the natural slow dynamic of these groundwater systems was significantly affected by mixing processes with contaminated modern groundwater coming from the shallow unconfined Boa Viagem aquifer. (4) The large exploitation of these aquifers leads to a modification of the flow directions and causes the intrusion through palaeo-channels of saline water probably coming from the Capibaribe River and from the last transgression episodes. These observations indicate that the current exploitation of the Cabo and Beberibe aquifers is unsustainable regarding the long renewal times of these groundwater systems as well as their ongoing contamination and salinisation. The groundwater cycle being much slower than the human development rhythm, it is essential to integrate the magnitude and rapidity of anthropogenic impacts on this extremely slow cycle to the water management concepts. - Highlights: • Study of anthropogenic impacts

Glacial recharge, salinisation and anthropogenic contamination in the coastal aquifers of Recife (Brazil)

International Nuclear Information System (INIS)

Chatton, E.; Aquilina, L.; Pételet-Giraud, E.; Cary, L.; Bertrand, G.; Labasque, T.

2016-01-01

Implying large residence times and complex water origins deep coastal aquifers are of particular interest as they are remarkable markers of climate, water use and land use changes. Over the last decades, the Metropolitan Region of Recife (Brazil) went through extensive environmental changes increasing the pressure on water resources and giving rise to numerous environmental consequences on the coastal groundwater systems. We analysed the groundwater of the deep aquifers Cabo and Beberibe that are increasingly exploited. The processes potentially affecting groundwater residence times and flow paths have been studied using a multi-tracer approach (CFCs, SF6, noble gases, 14C, 2H and 18O). The main findings of these investigations show that: (1) Groundwaters of the Cabo and Beberibe aquifers have long residence times and were recharged about 20,000 years ago. (2) Within these old groundwaters we can find palaeo-climate evidences from the last glacial period at the tropics with lower temperatures and dryer conditions than the present climate. (3) Recently, the natural slow dynamic of these groundwater systems was significantly affected by mixing processes with contaminated modern groundwater coming from the shallow unconfined Boa Viagem aquifer. (4) The large exploitation of these aquifers leads to a modification of the flow directions and causes the intrusion through palaeo-channels of saline water probably coming from the Capibaribe River and from the last transgression episodes. These observations indicate that the current exploitation of the Cabo and Beberibe aquifers is unsustainable regarding the long renewal times of these groundwater systems as well as their ongoing contamination and salinisation. The groundwater cycle being much slower than the human development rhythm, it is essential to integrate the magnitude and rapidity of anthropogenic impacts on this extremely slow cycle to the water management concepts. - Highlights: • Study of anthropogenic impacts

Residence times of groundwater and nitrate transport in coastal aquifer systems: Daweijia area, northeastern China

International Nuclear Information System (INIS)

Han, Dongmei; Cao, Guoliang; McCallum, James; Song, Xianfang

2015-01-01

Groundwater within the coastal aquifer systems of the Daweijia area in northeastern China is characterized by a large of variations (33–521 mg/L) in NO_3"− concentrations. Elevated nitrate concentrations, in addition to seawater intrusion in the Daweijia well field, both attributable to anthropogenic activities, may impact future water-management practices. Chemical and stable isotopic (δ"1"8O, δ"2H) analysis, "3H and CFCs methods were applied to provide a better understanding of the relationship between the distribution of groundwater mean residence time (MRT) and nitrate transport, and to identify sources of nitrate concentrations in the complex coastal aquifer systems. There is a relatively narrow range of isotopic composition (ranging from − 8.5 to − 7.0‰) in most groundwater. Generally higher tritium contents observed in the wet season relative to the dry season may result from rapid groundwater circulation in response to the rainfall through the preferential flow paths. In the well field, the relatively increased nitrate concentrations of groundwater, accompanied by the higher tritium contents in the wet season, indicate the nitrate pollution can be attributed to domestic wastes. The binary exponential and piston-flow mixing model (BEP) yielded feasible age distributions based on the conceptual model. The good inverse relationship between groundwater MRTs (92–467 years) and the NO_3"− concentrations in the shallow Quaternary aquifers indicates that elevated nitrate concentrations are attributable to more recent recharge for shallow groundwater. However, there is no significant relationship between the MRTs (8–411 years) and the NO_3"− concentrations existing in the carbonate aquifer system, due to the complex hydrogeological conditions, groundwater age distributions and the range of contaminant source areas. Nitrate in the groundwater system without denitrification effects could accumulate and be transported for tens of years, through the

Residence times of groundwater and nitrate transport in coastal aquifer systems: Daweijia area, northeastern China

Energy Technology Data Exchange (ETDEWEB)

Han, Dongmei [Key Laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101 (China); National Centre for Groundwater Research and Training, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Cao, Guoliang [National Centre for Groundwater Research and Training, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Center for Water Research, College of Engineering, Peking University, Beijing 100871 (China); McCallum, James [National Centre for Groundwater Research and Training, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); School of the Environment, Flinders University, GPO Box 2100, Adelaide, SA 5001 (Australia); Song, Xianfang [Key Laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101 (China)

2015-12-15

Groundwater within the coastal aquifer systems of the Daweijia area in northeastern China is characterized by a large of variations (33–521 mg/L) in NO{sub 3}{sup −} concentrations. Elevated nitrate concentrations, in addition to seawater intrusion in the Daweijia well field, both attributable to anthropogenic activities, may impact future water-management practices. Chemical and stable isotopic (δ{sup 18}O, δ{sup 2}H) analysis, {sup 3}H and CFCs methods were applied to provide a better understanding of the relationship between the distribution of groundwater mean residence time (MRT) and nitrate transport, and to identify sources of nitrate concentrations in the complex coastal aquifer systems. There is a relatively narrow range of isotopic composition (ranging from − 8.5 to − 7.0‰) in most groundwater. Generally higher tritium contents observed in the wet season relative to the dry season may result from rapid groundwater circulation in response to the rainfall through the preferential flow paths. In the well field, the relatively increased nitrate concentrations of groundwater, accompanied by the higher tritium contents in the wet season, indicate the nitrate pollution can be attributed to domestic wastes. The binary exponential and piston-flow mixing model (BEP) yielded feasible age distributions based on the conceptual model. The good inverse relationship between groundwater MRTs (92–467 years) and the NO{sub 3}{sup −} concentrations in the shallow Quaternary aquifers indicates that elevated nitrate concentrations are attributable to more recent recharge for shallow groundwater. However, there is no significant relationship between the MRTs (8–411 years) and the NO{sub 3}{sup −} concentrations existing in the carbonate aquifer system, due to the complex hydrogeological conditions, groundwater age distributions and the range of contaminant source areas. Nitrate in the groundwater system without denitrification effects could accumulate and be

Electrical Resistivity Imaging and the Saline Water Interface in High-Quality Coastal Aquifers

Science.gov (United States)

Costall, A.; Harris, B.; Pigois, J. P.

2018-07-01

Population growth and changing climate continue to impact on the availability of natural resources. Urbanization of vulnerable coastal margins can place serious demands on shallow groundwater. Here, groundwater management requires definition of coastal hydrogeology, particularly the seawater interface. Electrical resistivity imaging (ERI) appears to be ideally suited for this purpose. We investigate challenges and drivers for successful electrical resistivity imaging with field and synthetic experiments. Two decades of seawater intrusion monitoring provide a basis for creating a geo-electrical model suitable for demonstrating the significance of acquisition and inversion parameters on resistivity imaging outcomes. A key observation is that resistivity imaging with combinations of electrode arrays that include dipole-dipole quadrupoles can be configured to illuminate consequential elements of coastal hydrogeology. We extend our analysis of ERI to include a diverse set of hydrogeological settings along more than 100 km of the coastal margin passing the city of Perth, Western Australia. Of particular importance are settings with: (1) a classic seawater wedge in an unconfined aquifer, (2) a shallow unconfined aquifer over an impermeable substrate, and (3) a shallow multi-tiered aquifer system over a conductive impermeable substrate. We also demonstrate a systematic increase in the landward extent of the seawater wedge at sites located progressively closer to the highly urbanized center of Perth. Based on field and synthetic ERI experiments from a broad range of hydrogeological settings, we tabulate current challenges and future directions for this technology. Our research contributes to resolving the globally significant challenge of managing seawater intrusion at vulnerable coastal margins.

Electrical Resistivity Imaging and the Saline Water Interface in High-Quality Coastal Aquifers

Science.gov (United States)

Costall, A.; Harris, B.; Pigois, J. P.

2018-05-01

Population growth and changing climate continue to impact on the availability of natural resources. Urbanization of vulnerable coastal margins can place serious demands on shallow groundwater. Here, groundwater management requires definition of coastal hydrogeology, particularly the seawater interface. Electrical resistivity imaging (ERI) appears to be ideally suited for this purpose. We investigate challenges and drivers for successful electrical resistivity imaging with field and synthetic experiments. Two decades of seawater intrusion monitoring provide a basis for creating a geo-electrical model suitable for demonstrating the significance of acquisition and inversion parameters on resistivity imaging outcomes. A key observation is that resistivity imaging with combinations of electrode arrays that include dipole-dipole quadrupoles can be configured to illuminate consequential elements of coastal hydrogeology. We extend our analysis of ERI to include a diverse set of hydrogeological settings along more than 100 km of the coastal margin passing the city of Perth, Western Australia. Of particular importance are settings with: (1) a classic seawater wedge in an unconfined aquifer, (2) a shallow unconfined aquifer over an impermeable substrate, and (3) a shallow multi-tiered aquifer system over a conductive impermeable substrate. We also demonstrate a systematic increase in the landward extent of the seawater wedge at sites located progressively closer to the highly urbanized center of Perth. Based on field and synthetic ERI experiments from a broad range of hydrogeological settings, we tabulate current challenges and future directions for this technology. Our research contributes to resolving the globally significant challenge of managing seawater intrusion at vulnerable coastal margins.

Characterization of the lowland coastal aquifer of Comacchio (Ferrara, Italy): Hydrology, hydrochemistry and evolution of the system

Science.gov (United States)

Giambastiani, B. M. S.; Colombani, N.; Mastrocicco, M.; Fidelibus, M. D.

2013-09-01

This study delineates the actual hydrogeochemistry and the geological evolution of an unconfined coastal aquifer located in a lowland setting in order to understand the drivers of the groundwater salinization. Physical aquifer parameterization highlights a vertical hydraulic gradient due to the presence of a heavy drainage system, which controls the hydrodynamics of this coastal area, forcing groundwater to flow from the bottom toward the top of the aquifer. As a consequence, relict seawater in stable density stratification, preserved within low permeability sediments in the deepest portion of the aquifer, has been drawn upward. The hydrogeochemical investigations allow identifying the role of seepage and water-sediment interactions in the aquifer salinization process and in the modification of groundwater chemistry. Mixing between freshwater and saltwater occurs; however, it is neither the only nor the dominant process driving groundwater hydrochemistry. In the aquifer several concurring and competing water-sediment interactions - as NaCl solution, ion-exchange, calcite and dolomite dissolution/precipitation, oxidation of organic matter, and sulfate bacterial reduction - are triggered by or overlap freshwater-saltwater mixing The hyper-salinity found in the deepest portion of the aquifer cannot be associated with present seawater intrusion, but suggests the presence of salt water of marine origin, which was trapped in the inter-basin during the Holocene transgression. The results of this study contribute to a better understanding of groundwater dynamics and salinization processes in this lowland coastal aquifer.

Origin and distribution of saline groundwaters in the upper Miocene aquifer system, coastal Rhodope area, northeastern Greece

Science.gov (United States)

Petalas, C. P.; Diamantis, I. B.

1999-06-01

This paper describes the origins and distribution of saline groundwaters in the coastal area of Rhodope, Greece. The aquifer system includes two aquifers within coarse-grained alluvial sediments in the coastal part of the study area. Two major water-quality groups occur in the study area, namely Ca2+-rich saline groundwater and Ca2+-poor, almost fresh groundwater. The main process controlling the groundwater chemistry is the exchange of calcium and sodium between the aquifer matrix and intruding seawater. The natural salt water in the study area is probably residual water that infiltrated the aquifer system during repeated marine transgressions in late Pleistocene time. Seawater intrusion into the coastal aquifer system occurs as a result of overpumping in two seawater wedges separated vertically by a low-permeability layer. The rate of intrusion averages 0.8 m/d and is less than expected due to a decline of the aquifer's permeability at the interface with the seawater. The application of several hydrochemical techniques (Piper and Durov diagrams; Na+/Cl-, Ca2+/Cl-, Mg2+/Cl-, and Br-/Cl- molar ratios; Ca2+/Mg2+ weight ratio; and chloride concentrations), combined with field observations, may lead to a better explanation of the origin of the saline groundwater.

Planning report for the Gulf Coast Regional Aquifer-System Analysis in the Gulf of Mexico coastal plain, United States

Science.gov (United States)

Grubb, Hayes F.

1984-01-01

Large quantities of water for municipal, industrial and agriculture use are supplied from the aquifers in Tertiary and younger sediments over an area of about 225,000 square miles in the Coastal Plain of Alabama, Arkansas, Florida, Illinois, Kentucky, Louisiana, Mississippi, Missouri, Tennessee, and Texas. Three regional aquifer systems, the Mississippi Embayment aquifer system, the Coastal Lowlands aquifer system, and the Texas Coastal Uplands aquifer system have been developed to varying degrees throughout the area. A variety of problems has resulted from development such as movement of the saline-freshwater interface into parts of aquifers that were previously fresh, lowering of the potentiometric surface with resulting increases in pumping lift, and land-surface subsidence due to the compaction of clays within the aquifer. Increased demand for ground water is anticipated to meet the needs of urban growth, expanded energy development, and growth of irrigated agriculture. The U. S. Geological Survey initiated an eightyear study in 1981 to define the geohydrologic framework, describe the chemistry of the ground water, and to analyze the regional ground-water flow patterns. The objectives, plan, and organization of the study are described in this report and the major tasks to be undertaken are outlined.

The Maryland Coastal Plain Aquifer Information System: A GIS-based tool for assessing groundwater resources

Science.gov (United States)

Andreasen, David C.; Nardi, Mark R.; Staley, Andrew W.; Achmad, Grufron; Grace, John W.

2016-01-01

Groundwater is the source of drinking water for ∼1.4 million people in the Coastal Plain Province of Maryland (USA). In addition, groundwater is essential for commercial, industrial, and agricultural uses. Approximately 0.757 × 109 L d–1 (200 million gallons/d) were withdrawn in 2010. As a result of decades of withdrawals from the coastal plain confined aquifers, groundwater levels have declined by as much as 70 m (230 ft) from estimated prepumping levels. Other issues posing challenges to long-term groundwater sustainability include degraded water quality from both man-made and natural sources, reduced stream base flow, land subsidence, and changing recharge patterns (drought) caused by climate change. In Maryland, groundwater supply is managed primarily by the Maryland Department of the Environment, which seeks to balance reasonable use of the resource with long-term sustainability. The chief goal of groundwater management in Maryland is to ensure safe and adequate supplies for all current and future users through the implementation of appropriate usage, planning, and conservation policies. To assist in that effort, the geographic information system (GIS)–based Maryland Coastal Plain Aquifer Information System was developed as a tool to help water managers access and visualize groundwater data for use in the evaluation of groundwater allocation and use permits. The system, contained within an ESRI ArcMap desktop environment, includes both interpreted and basic data for 16 aquifers and 14 confining units. Data map layers include aquifer and ­confining unit layer surfaces, aquifer extents, borehole information, hydraulic properties, time-series groundwater-level data, well records, and geophysical and lithologic logs. The aquifer and confining unit layer surfaces were generated specifically for the GIS system. The system also contains select groundwater-quality data and map layers that quantify groundwater and surface-water withdrawals. The aquifer

Multiple recharge processes to heterogeneous Mediterranean coastal aquifers and implications on recharge rates evolution in time

Science.gov (United States)

Santoni, S.; Huneau, F.; Garel, E.; Celle-Jeanton, H.

2018-04-01

Climate change is nowadays widely considered to have major effects on groundwater resources. Climatic projections suggest a global increase in evaporation and higher frequency of strong rainfall events especially in Mediterranean context. Since evaporation is synonym of low recharge conditions whereas strong rainfall events are more favourable to recharge in heterogeneous subsurface contexts, a lack of knowledge remains then on the real ongoing and future drinking groundwater supply availability at aquifers scale. Due to low recharge potential and high inter-annual climate variability, this issue is strategic for the Mediterranean hydrosystems. This is especially the case for coastal aquifers because they are exposed to seawater intrusion, sea-level rise and overpumping risks. In this context, recharge processes and rates were investigated in a Mediterranean coastal aquifer with subsurface heterogeneity located in Southern Corsica (France). Aquifer recharge rates from combining ten physical and chemical methods were computed. In addition, hydrochemical and isotopic investigations were carried out through a monthly two years monitoring combining major ions and stable isotopes of water in rain, runoff and groundwater. Diffuse, focused, lateral mountain system and irrigation recharge processes were identified and characterized. A predominant focused recharge conditioned by subsurface heterogeneity is evidenced in agreement with variable but highly favourable recharge rates. The fast water transfer from the surface to the aquifer implied by this recharge process suggests less evaporation, which means higher groundwater renewal and availability in such Mediterranean coastal aquifers.

Coastal aquifer management under parameter uncertainty: Ensemble surrogate modeling based simulation-optimization

Science.gov (United States)

Janardhanan, S.; Datta, B.

2011-12-01

Surrogate models are widely used to develop computationally efficient simulation-optimization models to solve complex groundwater management problems. Artificial intelligence based models are most often used for this purpose where they are trained using predictor-predictand data obtained from a numerical simulation model. Most often this is implemented with the assumption that the parameters and boundary conditions used in the numerical simulation model are perfectly known. However, in most practical situations these values are uncertain. Under these circumstances the application of such approximation surrogates becomes limited. In our study we develop a surrogate model based coupled simulation optimization methodology for determining optimal pumping strategies for coastal aquifers considering parameter uncertainty. An ensemble surrogate modeling approach is used along with multiple realization optimization. The methodology is used to solve a multi-objective coastal aquifer management problem considering two conflicting objectives. Hydraulic conductivity and the aquifer recharge are considered as uncertain values. Three dimensional coupled flow and transport simulation model FEMWATER is used to simulate the aquifer responses for a number of scenarios corresponding to Latin hypercube samples of pumping and uncertain parameters to generate input-output patterns for training the surrogate models. Non-parametric bootstrap sampling of this original data set is used to generate multiple data sets which belong to different regions in the multi-dimensional decision and parameter space. These data sets are used to train and test multiple surrogate models based on genetic programming. The ensemble of surrogate models is then linked to a multi-objective genetic algorithm to solve the pumping optimization problem. Two conflicting objectives, viz, maximizing total pumping from beneficial wells and minimizing the total pumping from barrier wells for hydraulic control of

Geophysical characterization of saltwater intrusion in a coastal aquifer: The case of Martil-Alila plain (North Morocco)

Science.gov (United States)

Himi, Mahjoub; Tapias, Josefiina; Benabdelouahab, Sara; Salhi, Adil; Rivero, Luis; Elgettafi, Mohamed; El Mandour, Abdenabi; Stitou, Jamal; Casas, Albert

2017-02-01

Several factors can affect the quantity and the quality of groundwater resources, but in coastal aquifers seawater intrusion is often the most significant issue regarding freshwater supply. Further, saltwater intrusion is a worldwide issue because about seventy percent of the world's population lives in coastal regions. Generally, fresh groundwater not affected by saltwater intrusion is characterized by low salinity and therefore low electrical conductivity (EC) values. Consequently, high values of EC in groundwater along the coastline are usually associated to seawater intrusion. This effect is amplified if the coastal aquifer is overexploited with a subsequent gradual displacement of the freshwater-saltwater interface towards the continent. Delineation of marine intrusion in coastal aquifers has traditionally relied upon observation wells and collection of water samples. This approach may miss important hydrologic features related to saltwater intrusion in areas where access is difficult and where wells are widely spaced. Consequently, the scarcity of sampling points and sometimes their total absence makes the number of data available limited and most of the time not representative for mapping the spatial and temporal variability of groundwater salinity. In this study, we use a series of geophysical methods for characterizing the aquifer geometry and the extension of saltwater intrusion in the Martil-Alila coastal region (Morocco) as a complement to geological and hydrogeochemical data. For this reason, we carried out three geophysical surveys: Gravity, Electrical Resistivity and Frequency Domain Electromagnetic. The geometry of the basin has been determined from the interpretation of a detailed gravity survey. Electrical resistivity models derived from vertical electrical soundings allowed to characterize the vertical and the lateral extensions of aquifer formations. Finally, frequency domain electromagnetic methods allowed delineating the extension of the

Effects of Sea Level Rise on Groundwater Flow Paths in a Coastal Aquifer System

Science.gov (United States)

Morrissey, S. K.; Clark, J. F.; Bennett, M. W.; Richardson, E.; Stute, M.

2008-05-01

Changes in groundwater flow in the Floridan aquifer system, South Florida, from the rise in sea level at the end of the last glacial period may be indicative of changes coastal aquifers will experience with continued sea level rise. As sea level rises, the hydraulic head near the coast increases. Coastal aquifers can therefore experience decreased groundwater gradients (increased residence times) and seawater intrusion. Stable isotopes of water, dissolved noble gas temperatures, radiocarbon and He concentrations were analyzed in water collected from 68 wells in the Floridan aquifer system throughout South Florida. Near the recharge area, geochemical data along groundwater flow paths in the Upper Floridan aquifer show a transition from recently recharged groundwater to glacial-aged water. Down gradient from this transition, little variation is apparent in the stable isotopes and noble gas recharge temperatures, indicating that most of the Upper Floridan aquifer contains groundwater recharged during the last glacial period. The rapid 120-meter rise in sea level marking the end of the last glacial period increased the hydraulic head in the Floridan aquifer system near the coast, slowing the flow of groundwater from the recharge area to the ocean and trapping glacial-aged groundwater. The raised sea level also flooded half of the Florida platform and caused seawater to intrude into the Lower Floridan. This circulation of seawater in the Lower Floridan continues today as our data indicate that the groundwater is similar to modern seawater with a freshwater component entering vertically from the recharge area to the Upper Floridan.

Application of factor analysis to the hydrogeochemical study of a coastal aquifer

OpenAIRE

Ruiz Beviá, Francisco; Gomis Yagües, Vicente; Blasco Alemany, Pilar

1989-01-01

The use of numerical values for the chemical components of waters from an aquifer as input data for factor analysis is shown to be sometimes more convenient than the use of the logarithms of these figures. Factor analysis was applied to the hydrogeochemical study of a coastal aquifer located in Javea, Alicante (Spain). A set of factors was found which explained the source of the ions in the water and even certain chemical processes which accompany the intrusion of seawater, such as the strong...

Changes of freshwater-lens thickness in basaltic island aquifers overlain by thick coastal sediments

Science.gov (United States)

Rotzoll, Kolja; Oki, Delwyn S.; El-Kadi, Aly I.

2010-01-01

Freshwater-lens thickness and long-term changes in freshwater volume in coastal aquifers are commonly assessed through repeated measurement of salinity profiles from monitor wells that penetrate into underlying salt water. In Hawaii, the thickest measured freshwater lens is currently 262 m in dike-free, volcanic-rock aquifers that are overlain by thick coastal sediments. The midpoint depth (depth where salinity is 50% salt water) between freshwater and salt water can serve as an indicator for freshwater thickness. Most measured midpoints have risen over the past 40 years, indicating a shrinking lens. The mean rate of rise of the midpoint from 1999–2009 varied locally, with faster rates in highly developed areas (1.0 m/year) and slower rates in less developed areas (0.5 m/year). The thinning of the freshwater lenses is the result of long-term groundwater withdrawal and reduced recharge. Freshwater/salt-water interface locations predicted from measured water levels and the Ghyben-Herzberg principle may be deeper than measured midpoints during some periods and shallower during other periods, although depths may differ up to 100 m in some cases. Moreover, changes in the midpoint are slower than changes in water level. Thus, water levels may not be a reliable indicator of the amount of freshwater in a coastal aquifer.

Retoxification by heavy metals at land-sea interface in coastal aquifers

Science.gov (United States)

Fidelibus, Maria Dolores

2014-05-01

Although during the last decades a significant number of countermeasures have been put in place with respect to the release of pollutants into the environment, and emissions of many of these are in fact ceased, the signs of a generalized pollution are found with increasing frequency. The appearance of new signals may surprise, given that common sense leads us to believe that in a period of reduced emissions the environment should be in an improved state rather than in a worse one: however, the environmental effects of previous pollution are clearly appearing after a build-up of pollutants in the environment over the past decades, with a lag with respect to the activities that generated it.In particular, soils are the final receptor (sink) of pollutants as heavy metals, pesticides and fertilizers: the common belief that the heavy metals remain forever locked may, however, give a false sense of security: today it is no longer possible to ignore the fact that the soils involve potential long-term impacts.With this in mind we can open a window on some aspects of the nonlinear behavior of soils and detrital aquifers. Researches on the former are more frequent and help extending some results to the latter. As matter of fact, in response to variations in environmental conditions, sudden releases of pollutants accumulated in soils occur with a considerable delay compared to the input. The attention of the study is on coastal aquifers. The coastal areas in general are dynamic non-linear systems at the land-sea interface in perpetual chemical-physical disequilibrium: these areas are complex with regard to the constituent elements and subject to a set of variable boundary conditions (oscillating borderswith periodic and aperiodic frequency), to cyclic and non-cyclic variations of climatic conditions and anthropogenic forcing (permanent or transient), whose behavior is not easily predictable, and that act on different temporal and spatial scales.The question is: can the

Assessing aquifer storage and recovery feasibility in the Gulf Coastal Plains of Texas

Directory of Open Access Journals (Sweden)

W. Benjamin Smith

2017-12-01

Full Text Available Study region: The Gulf Coast and Carrizo-Wilcox aquifer systems in the Gulf Coastal Plains of Texas. Study focus: Aquifer storage and recovery is a water storage alternative that is underutilized in Texas, a state with both long periods of drought and high intensity storms. Future water storage plans in Texas almost exclusively rely on surface reservoirs, subject to high evaporative losses. This study seeks to identify sites where aquifer storage and recovery (ASR may be successful, especially in recovery of injected waters, by analyzing publicly-available hydrogeologic data. Transmissivity, hydraulic gradient, well density, depth to aquifer, and depth to groundwater are used in a GIS-based index to determine feasibility of implementing an ASR system in the Gulf Coast and Carrizo-Wilcox aquifer systems. New hydrological insights for the region: Large regions of the central and northern Gulf Coast and the central and southern Carrizo-Wilcox aquifer systems are expected to be hydrologically feasible regions for ASR. Corpus Christi, Victoria, San Antonio, Bryan, and College Station are identified as possible cities where ASR would be a useful water storage strategy. Keywords: Aquifer storage and recovery (ASR, GIS, Gulf coast, Carrizo-Wilcox, Managed aquifer recharge (MAR

Origin of water salinity in the coastal Sarafand aquifer (South-Lebanon)

International Nuclear Information System (INIS)

Hashash, Adnan; Aranyossy, J.F.

1996-01-01

Author.The geochemical and isotopic study, based on the analysis of twenty water samples from well in the coastal plain of Sarafand (South-Lebanon), permit to eliminate the hypothesis of marine intrusion in this aquifer. The increase of salinity observed in certain wells is due to the contamination of cretaceous aquifer water by the quaternary formations. The two poles of mixing are respectively characterized: by weak tritium contents (between 2 and 3 UT) and a value of stable isotopes (-5,9<0,18<-5,5) corresponding to the appearance of cretaceous formation area; by the high tritium contents and enrichment relative to heavy isotope in the mineralized water of superficial formations. On the other hand, the isotope contents permit the set a rapid renewal of the cretaceous aquifer water due to quick circulation in the Karstic system

The integrated impacts of natural processes and human activities on groundwater salinization in the coastal aquifers of Beihai, southern China

Science.gov (United States)

Li, Qinghua; Zhang, Yanpeng; Chen, Wen; Yu, Shaowen

2018-03-01

Salinization in coastal aquifers is usually related to both seawater intrusion and water-rock interaction. The results of chemical and isotopic methods were combined to identify the origin and processes of groundwater salinization in Daguansha area of Beihai, southern China. The concentrations of the major ions that dominate in seawater (Cl-, Na+, Ca2+, Mg2+ and SO4 2- ), as well as the isotopic content and ratios (2H, 18O, 87Sr/86Sr and 13C), suggest that the salinization occurring in the aquifer of the coastal plain is related to seawater and that the prevailing hydrochemical processes are evaporation, mixing, dissolution and ion exchange. For the unconfined aquifer, groundwater salinization has occurred in an area that is significantly influenced by land-based sea farming. The integrated impacts of seawater intrusion from the Beibuwan Gulf and infiltration of seawater from the culture ponds are identified in the shallowest confined aquifer (I) in the middle of the area (site BBW2). Leakage from this polluted confined aquifer causes the salinization of groundwater in the underlying confined aquifer (II). At the coastal monitoring site (BBW3), confined aquifer I and lower confined aquifer II are heavily contaminated by seawater intrusion. The weak connectivity between the upper aquifers, and the seaward movement of freshwater, prevents saltwater from encroaching the deepest confined aquifer (III). A conceptual model is presented. Above all, understanding of the origin and processes of groundwater salinization will provide essential information for the planning and sustainable management of groundwater resources in this region.

Semianalytical solutions for contaminant transport under variable velocity field in a coastal aquifer

Science.gov (United States)

Koohbor, Behshad; Fahs, Marwan; Ataie-Ashtiani, Behzad; Simmons, Craig T.; Younes, Anis

2018-05-01

Existing closed-form solutions of contaminant transport problems are limited by the mathematically convenient assumption of uniform flow. These solutions cannot be used to investigate contaminant transport in coastal aquifers where seawater intrusion induces a variable velocity field. An adaptation of the Fourier-Galerkin method is introduced to obtain semi-analytical solutions for contaminant transport in a confined coastal aquifer in which the saltwater wedge is in equilibrium with a freshwater discharge flow. Two scenarios dealing with contaminant leakage from the aquifer top surface and contaminant migration from a source at the landward boundary are considered. Robust implementation of the Fourier-Galerkin method is developed to efficiently solve the coupled flow, salt and contaminant transport equations. Various illustrative examples are generated and the semi-analytical solutions are compared against an in-house numerical code. The Fourier series are used to evaluate relevant metrics characterizing contaminant transport such as the discharge flux to the sea, amount of contaminant persisting in the groundwater and solute flux from the source. These metrics represent quantitative data for numerical code validation and are relevant to understand the effect of seawater intrusion on contaminant transport. It is observed that, for the surface contamination scenario, seawater intrusion limits the spread of the contaminant but intensifies the contaminant discharge to the sea. For the landward contamination scenario, moderate seawater intrusion affects only the spatial distribution of the contaminant plume while extreme seawater intrusion can increase the contaminant discharge to the sea. The developed semi-analytical solution presents an efficient tool for the verification of numerical models. It provides a clear interpretation of the contaminant transport processes in coastal aquifers subject to seawater intrusion. For practical usage in further studies, the full

Modelling the salinization of a coastal lagoon-aquifer system

Science.gov (United States)

Colombani, N.; Mastrocicco, M.

2017-08-01

In this study, a coastal area constituted by alternations of saline-brackish lagoons and freshwater bodies was studied and modelled to understand the hydrological processes occurring between the lagoons, the groundwater system of the Po River Delta (Italy) and the Adriatic Sea. The contribution of both evaporation and anthropogenic factors on groundwater salinization was assessed by means of soil, groundwater and surface water monitoring. Highresolution multi-level samplers were used to capture salinity gradients within the aquifer and surface water bodies. Data were employed to calibrate a density-dependent numerical transport model implemented with SEAWAT code along a transect perpendicular to the coast line. The results show that the lagoon is hydraulically well connected with the aquifer, which provides the major source of salinity because of the upcoming of paleo-seawater from the aquitard laying at the base of the unconfined aquifer. On the contrary, the seawater (diluted by the freshwater river outflow) creates only a limited saltwater wedge. The increase in groundwater salinity could be of serious concern, especially for the pinewood located in the dune near the coast, sensitive to salinity increases. This case study represents an interesting paradigm for other similar environmental setting, where the assumption of classical aquifer salinization from a saltwater wedge intruding from the sea is often not representative of the actual aquifer’s salinization mechanisms.

Localized sulfate-reducing zones in a coastal plain aquifer

Science.gov (United States)

Brown, C.J.; Coates, J.D.; Schoonen, M.A.A.

1999-01-01

High concentrations of dissolved iron in ground water of coastal plain or alluvial aquifers contribute to the biofouling of public supply wells for which treatment and remediation is costly. Many of these aquifers, however, contain zones in which microbial sulfate reduction and the associated precipitation of iron-sulfide minerals decreases iron mobility. The principal water-bearing aquifer (Magothy Aquifer of Cretaceous age) in Suffolk County, New York, contains localized sulfate-reducing zones in and near lignite deposits, which generally are associated with clay lenses. Microbial analyses of core samples amended with [14C]-acetate indicate that microbial sulfate reduction is the predominant terminal-electron-accepting process (TEAP) in poorly permeable, lignite-rich sediments at shallow depths and near the ground water divide. The sulfate-reducing zones are characterized by abundant lignite and iron-sulfide minerals, low concentrations of Fe(III) oxyhydroxides, and by proximity to clay lenses that contain pore water with relatively high concentrations of sulfate and dissolved organic carbon. The low permeability of these zones and, hence, the long residence time of ground water within them, permit the preservation and (or) allow the formation of iron-sulfide minerals, including pyrite and marcasite. Both sulfate-reducing bacteria (SRB) and iron-reducing bacteria (IRB) are present beneath and beyond the shallow sulfate-reducing zones. A unique Fe(III)-reducing organism, MD-612, was found in core sediments from a depth of 187 m near the southern shore of Long Island. The distribution of poorly permeable, lignite-rich, sulfate-reducing zones with decreased iron concentration is varied within the principal aquifer and accounts for the observed distribution of dissolved sulfate, iron, and iron sulfides in the aquifer. Locating such zones for the placement of production wells would be difficult, however, because these zones are of limited aerial extent.

Reactive dispersive contaminant transport in coastal aquifers: Numerical simulation of a reactive Henry problem

KAUST Repository

Nick, H.M.; Raoof, A.; Centler, F.; Thullner, M.; Regnier, P.

2013-01-01

The reactive mixing between seawater and terrestrial water in coastal aquifers influences the water quality of submarine groundwater discharge. While these waters come into contact at the seawater groundwater interface by density driven flow

Numerical modeling of groundwater flow in the coastal aquifer system of Taranto (southern Italy)

Science.gov (United States)

De Filippis, Giovanna; Giudici, Mauro; Negri, Sergio; Margiotta, Stefano; Cattaneo, Laura; Vassena, Chiara

2014-05-01

The Mediterranean region is characterized by a strong development of coastal areas with a high concentration of water-demanding human activities, resulting in weakly controlled withdrawals of groundwater which accentuate the saltwater intrusion phenomenon. The worsening of groundwater quality is a huge problem especially for those regions, like Salento (southern Italy), where a karst aquifer system represents the most important water resource because of the deficiency of a well developed superficial water supply. In this frame, the first 2D numerical model describing the groundwater flow in the karst aquifer of Salento peninsula was developed by Giudici et al. [1] at the regional scale and then improved by De Filippis et al. [2]. In particular, the estimate of the saturated thickness of the deep aquifer highlighted that the Taranto area is particularly sensitive to the phenomenon of seawater intrusion, both for the specific hydrostratigraphic configuration and for the presence of highly water-demanding industrial activities. These remarks motivate a research project which is part of the research program RITMARE (The Italian Research for the Sea), within which a subprogram is specifically dedicated to the problem of the protection and preservation of groundwater quality in Italian coastal aquifers and in particular, among the others, in the Taranto area. In this context, the CINFAI operative unit aims at providing a contribution to the characterization of groundwater in the study area. The specific objectives are: a. the reconstruction of the groundwater dynamic (i.e., the preliminary identification of a conceptual model for the aquifer system and the subsequent modeling of groundwater flow in a multilayered system which is very complex from the hydrostratigraphical point of view); b. the characterization of groundwater outflows through submarine and subaerial springs and the water exchanges with the shallow coastal water bodies (e.g. Mar Piccolo) and the off

What Drives Saline Circulation Cells in Coastal Aquifers? An Energy Balance for Density-Driven Groundwater Systems

Science.gov (United States)

Harvey, C. F.; Michael, H. A.

2017-12-01

We formulate the energy balance for coastal groundwater systems and apply it to: (1) Explain the energy driving offshore saline circulation cells, and; (2) Assess the accuracy of numerical simulations of coastal groundwater systems. The flow of fresh groundwater to the ocean is driven by the loss of potential energy as groundwater drops from the elevation of the inland watertable, where recharge occurs, to discharge at sea level. This freshwater flow creates an underlying circulation cell of seawater, drawn into coastal aquifers offshore and discharging near shore, that adds to total submarine groundwater discharge. The saline water in the circulation cell enters and exits the aquifer through the sea floor at the same hydraulic potential. Existing theory explains that the saline circulation cell is driven by mixing of fresh and saline without any additional source of potential or mechanical power. This explanation raises a basic thermodynamic question: what is the source of energy that drives the saline circulation cell? Here, we resolve this question by building upon Hubbert's conception of hydraulic potential to formulate an energy balance for density-dependent flow and salt transport through an aquifer. We show that, because local energy dissipation within the aquifer is proportional to the square of the groundwater velocity, more groundwater flow may be driven through an aquifer for a given energy input if local variations in velocity are smoothed. Our numerical simulations of coastal groundwater systems show that dispersion of salt across the fresh-saline interface spreads flow over larger volumes of the aquifer, smoothing the velocity field, and increasing total flow and submarine groundwater discharge without consuming more power. The energy balance also provides a criterion, in addition to conventional mass balances, for judging the accuracy of numerical solutions of non-linear density-dependent flow problems. Our results show that some numerical

Integrated subsurface water solutions for coastal environments through integrated pump&treat and aquifer storage and recovery (ASR) schemes

Science.gov (United States)

Perdikaki, Martha; Kallioras, Andreas; Christoforidis, Christophoros; Iossifidis, Dimitris; Zafeiropoulos, Anastasios; Dimitriadis, Klisthenis; Makropoulos, Christos; Raat, Klaasjan; van den Berg, Gerard

2016-04-01

Coastal wetlands in semi-arid regions, as in Circum-Mediterranean, are considered important ecosystems that provide valuable services to human population and the environment, such as: flood protection, erosion control, wildlife habitat, water quality, recreation and carbon sequestration. Un-managed surface and groundwater exploitation in these areas usually leads to deterioration of such sensitive ecosystems by means of water resources degradation and/or increased salinity. Groundwater usually plays a vital role for the sustainability of these hydrological systems, as the underlying aquifers operate as regulators for both quantity and quality of their waters. Multi-layer and multi-objective Managed Aquifer Recharge (MAR) systems can be proved effective groundwater engineered solutions for the restoration of deteriorated coastal wetlands in semi- and arid regions. The plain of Marathon is a typical Mediterranean environment that hosts a naturally occurring -and today degraded- coastal wetland with the characteristics of a distinct ecosystem linked to a typical coastal hydrogeological system of a semi-arid region; and therefore can serve as a model for similar systems world-wide. The geo-hydrological setting of the area involves a multi-layer aquifer system consisting of (i) an upper un-consolidated formation of depositional unit dominated mostly by fluvial sediments and (ii) the surrounding and underlying karstified marbles; both being linked to the investigated wetland and also subjected to seawater encroachment. A smart engineered MAR system via an optimised Pump & Treat system integrated with an Aquifer Storage and Recovery (ASR) scheme in this area would include the abstraction of brackish groundwater from the deeper karst aquifer at a location close to the shoreline and direct treatment with Reverse Osmosis (RO). for desalination. Two-fold re-use scheme of the purified effluent can then be engineered for (i) the restoration of the coastal wetland; and (ii

A study on the influence of tides on the water table conditions of the shallow coastal aquifers

Science.gov (United States)

Singaraja, C.; Chidambaram, S.; Jacob, Noble

2018-03-01

Tidal variation and water level in aquifer is an important function in the coastal environment, this study attempts to find the relationship between water table fluctuation and tides in the shallow coastal aquifers. The study was conducted by selecting three coastal sites and by monitoring the water level for every 2-h interval in 24 h of observation. The study was done during two periods of full moon and new moon along the Cuddalore coastal region of southern part of Tamil Nadu, India. The study shows the relationship between tidal variation, water table fluctuations, dissolved oxygen, and electrical conductivity. An attempt has also been made in this study to approximate the rate of flow of water. Anyhow, the differences are site specific and the angle of inclination of the water table shows a significant relation to the mean sea level, with respect to the distance of the point of observation from the sea and elevation above mean sea level.

A multi-method approach for groundwater resource assessment in coastal carbonate (karst) aquifers: the case study of Sierra Almijara (southern Spain)

Science.gov (United States)

Andreo, B.; Barberá, J. A.; Mudarra, M.; Marín, A. I.; García-Orellana, J.; Rodellas, V.; Pérez, I.

2018-02-01

Understanding the transference of water resources within hydrogeological systems, particularly in coastal aquifers, in which groundwater discharge may occur through multiple pathways (through springs, into rivers and streams, towards the sea, etc.), is crucial for sustainable groundwater use. This research aims to demonstrate the usefulness of the application of conventional recharge assessment methods coupled to isotopic techniques for accurately quantifying the hydrogeological balance and submarine groundwater discharge (SGD) from coastal carbonate aquifers. Sierra Almijara (Southern Spain), a carbonate aquifer formed of Triassic marbles, is considered as representative of Mediterranean coastal karst formations. The use of a multi-method approach has permitted the computation of a wide range of groundwater infiltration rates (17-60%) by means of direct application of hydrometeorological methods (Thornthwaite and Kessler) and spatially distributed information (modified APLIS method). A spatially weighted recharge rate of 42% results from the most coherent information on physiographic and hydrogeological characteristics of the studied system. Natural aquifer discharge and groundwater abstraction have been volumetrically quantified, based on flow and water-level data, while the relevance of SGD was estimated from the spatial analysis of salinity, 222Rn and the short-lived radium isotope 224Ra in coastal seawater. The total mean aquifer discharge (44.9-45.9 hm3 year-1) is in agreement with the average recharged groundwater (44.7 hm3 year-1), given that the system is volumetrically equilibrated during the study period. Besides the groundwater resources assessment, the methodological aspects of this research may be interesting for groundwater management and protection strategies in coastal areas, particularly karst environments.

Investigating the salinization and freshening processes of coastal groundwater resources in Urmia aquifer, NW Iran.

Science.gov (United States)

Amiri, Vahab; Nakhaei, Mohammad; Lak, Razyeh; Kholghi, Majid

2016-04-01

This paper presents the results of an assessment about interaction between Urmia Lake (UL) and coastal groundwater in the Urmia aquifer (UA). This aquifer is the most significant contributor to the freshwater supply of the coastal areas. The use of hydrochemical facies can be very useful to identify the saltwater encroachment or freshening phases in the coastal aquifers. In this study, the analysis of salinization/freshening processes was carried out through the saturation index (SI), ionic deltas (Δ), binary diagrams, and hydrochemical facies evolution (HFE) diagram. Based on the Gibbs plot, the behavior of the major ions showed that the changes in the chemical composition of the groundwater are mainly controlled by the water-soil/rock interaction zone and few samples are relatively controlled by evaporation. A possible explanation for this phenomenon is that the deposited chloride and sulfate particles can form the minor salinity source in some coastal areas when washed down by precipitation. The SI calculations showed that all groundwater samples, collected in these periods, show negative saturation indices, which indicate undersaturation with respect to anhydrite, gypsum, and halite. In addition, except in a few cases, all other samples showed the undersaturation with respect to the carbonate minerals such as aragonite, calcite, and dolomite. Therefore, these minerals are susceptible to dissolution. In the dry season, the SI calculations showed more positive values with respect to dolomite, especially in the northern part of UA, which indicated a higher potential for precipitation and deposition of dolomite. The percentage of saltwater in the groundwater samples of Urmia plain was very low, ranging between 0.001 and 0.79 % in the wet season and 0.0004 and 0.81 % in the dry season. The results of HFE diagram, which was taken to find whether the aquifer was in the saltwater encroachment phase or in the freshening phase, indicated that except for a few wells

LCA Cookbook

DEFF Research Database (Denmark)

Hauschild, Michael Z.; Bjørn, Anders

2018-01-01

The LCA cookbook presents the provisions and actions from the ILCD Handbook that are central in the performance of an LCA. The selection is intended to cover all those activities that an LCA practitioner needs to undertake in a typical process-LCA , and the presentation follows the normal progres...... progression of the LCA work according to the ISO framework. For explanation of the reasoning behind the actions, the reader is referred to the presentation of the methodological elements in Part 2 of the book....

Aquifer geochemistry at potential aquifer storage and recovery sites in coastal plain aquifers in the New York city area, USA

Science.gov (United States)

Brown, C.J.; Misut, P.E.

2010-01-01

The effects of injecting oxic water from the New York city (NYC) drinking-water supply and distribution system into a nearby anoxic coastal plain aquifer for later recovery during periods of water shortage (aquifer storage and recovery, or ASR) were simulated by a 3-dimensional, reactive-solute transport model. The Cretaceous aquifer system in the NYC area of New York and New Jersey, USA contains pyrite, goethite, locally occurring siderite, lignite, and locally varying amounts of dissolved Fe and salinity. Sediment from cores drilled on Staten Island and western Long Island had high extractable concentrations of Fe, Mn, and acid volatile sulfides (AVS) plus chromium-reducible sulfides (CRS) and low concentrations of As, Pb, Cd, Cr, Cu and U. Similarly, water samples from the Lloyd aquifer (Cretaceous) in western Long Island generally contained high concentrations of Fe and Mn and low concentrations of other trace elements such as As, Pb, Cd, Cr, Cu and U, all of which were below US Environmental Protection Agency (USEPA) and NY maximum contaminant levels (MCLs). In such aquifer settings, ASR operations can be complicated by the oxidative dissolution of pyrite, low pH, and high concentrations of dissolved Fe in extracted water.The simulated injection of buffered, oxic city water into a hypothetical ASR well increased the hydraulic head at the well, displaced the ambient groundwater, and formed a spheroid of injected water with lower concentrations of Fe, Mn and major ions in water surrounding the ASR well, than in ambient water. Both the dissolved O2 concentrations and the pH of water near the well generally increased in magnitude during the simulated 5-a injection phase. The resultant oxidation of Fe2+ and attendant precipitation of goethite during injection provided a substrate for sorption of dissolved Fe during the 8-a extraction phase. The baseline scenario with a low (0.001M) concentration of pyrite in aquifer sediments, indicated that nearly 190% more water

Application and evaluation of electromagnetic methods for imaging saltwater intrusion in coastal aquifers: Seaside Groundwater Basin, California

Science.gov (United States)

Nenna, Vanessa; Herckenrather, Daan; Knight, Rosemary; Odlum, Nick; McPhee, Darcy

2013-01-01

Developing effective resource management strategies to limit or prevent saltwater intrusion as a result of increasing demands on coastal groundwater resources requires reliable information about the geologic structure and hydrologic state of an aquifer system. A common strategy for acquiring such information is to drill sentinel wells near the coast to monitor changes in water salinity with time. However, installation and operation of sentinel wells is costly and provides limited spatial coverage. We studied the use of noninvasive electromagnetic (EM) geophysical methods as an alternative to installation of monitoring wells for characterizing coastal aquifers. We tested the feasibility of using EM methods at a field site in northern California to identify the potential for and/or presence of hydraulic communication between an unconfined saline aquifer and a confined freshwater aquifer. One-dimensional soundings were acquired using the time-domain electromagnetic (TDEM) and audiomagnetotelluric (AMT) methods. We compared inverted resistivity models of TDEM and AMT data obtained from several inversion algorithms. We found that multiple interpretations of inverted models can be supported by the same data set, but that there were consistencies between all data sets and inversion algorithms. Results from all collected data sets suggested that EM methods are capable of reliably identifying a saltwater-saturated zone in the unconfined aquifer. Geophysical data indicated that the impermeable clay between aquifers may be more continuous than is supported by current models.

Susceptibility to saline contamination of coastal confined aquifer of the Uraba banana axis with hydrogeochemical and isotopic techniques

International Nuclear Information System (INIS)

Paredes Zuniga, Vanessa

2010-01-01

The project has covered an area of study of 8916 km 2 is located in the Northwestern part of the Department of Antioquia, Colombia. Interest area is geologically constituted by tertiary sedimentary rocks (T1 and T2) and alluvial deposits (Quaternary). Hydrogeological units, potentially better use of groundwater, have been established for the unit T2 (confined aquifer) and quaternary deposits.) The area has been of 2600 mm/year to 3600 mm/year of average rainfall. The susceptibility to saline contamination has been determined of coastal aquifer of the Uraba banana axis. Hydrochemical and geological information, geophysics, hydraulic and hydrochemical is used improving existing conceptual hydrogeological model. A hydrochemical characterization has been performed to evaluate the processes of salinity in the confined aquifer. The integration of geological information, geophysical and hydrogeological has been methodology used to validate the hydraulic characteristics of the aquifer, its geometry and operation, updating the conceptual hydrogeological model. The use of complementary tools been able to determine and identify processes that may affect natural physico-chemical characteristics of groundwater. The results have showed that salinization processes present in the coastal aquifer of Uraba Banana Axis could be linked to water-rock interaction, to mixtures with water have become saline as a result of transgression - regression processes in the former study. The hydrogeochemical techniques have become a complementary tool to the hydrogeology allowing respond the questions were presented in complex systems, such as the case of coastal aquifers, where sanitation is usually associated with saline intrusion processes and can also be obeying the conjunction with other hydroclimatological and hydrodynamic aspects. (author) [es

LASTRIG -A Multiple Parametric Method of Assessment of Salinization Vulnerability of a Coastal Aquifer in Pennar Delta, India

Science.gov (United States)

Kesireddy, K.; Mareddy, A.

2007-05-01

Coastal populations are critically dependent upon the coastal aquifers for their freshwater requirements. Excessive withdrawal of groundwater leads to saline incursion and the consequent degradation of quality and quantity of freshwater. The paper describes a multiple parametric method of assessment of vulnerability of the coastal aquifer in Pennar delta, south India, in the context of the hydrogeological, biophysical, geochemical and socioeconomic environments of the delta. Seven parameters, forming the acronym LASTRIG viz. landuse, aquifer type, soil depth, groundwater table, rainfall, soil infiltration and geomorphology are made use in the assessment, and involve the use of remote sensing, GIS and modeling tools. The parameters are weighted, and a suitable ranking system has been designed to quantify the degree of vulnerability of the aquifer for salinization. It has been found that zones with high vulnerability index correlate well with zones of high TDS and chloride contents of groundwater. This observation thus validates the geochemical basis of the proposed LASTRIG system. The new system has been found useful in the management of the groundwater resources of the delta region. It has been made use of identify the aquifer segments which are in danger of being degraded, to enable the decision- makers to design counter measures to avoid further deterioration in water quality. Where the groundwater has already been rendered non-potable because of saline incursion, the LASTRIG index could be made use to identify possible use of that water for drinking by cattle, and for growing of salt-tolerant vegetables (e.g. beetroot and lettuce), and trees (e.g. casuarinas obese, Prosopis juliflora)

Hydrochemistry and Isotope Hydrology for Groundwater Sustainability of the Coastal Multilayered Aquifer System (Zhanjiang, China

Directory of Open Access Journals (Sweden)

Pengpeng Zhou

2017-01-01

Full Text Available Groundwater sustainability has become a critical issue for Zhanjiang (China because of serious groundwater level drawdown induced by overexploitation of its coastal multilayered aquifer system. It is necessary to understand the origins, material sources, hydrochemical processes, and dynamics of the coastal groundwater in Zhanjiang to support its sustainable management. To this end, an integrated analysis of hydrochemical and isotopic data of 95 groundwater samples was conducted. Hydrochemical analysis shows that coastal groundwater is fresh; however, relatively high levels of Cl−, Mg2+, and total dissolved solid (TDS imply slight seawater mixing with coastal unconfined groundwater. Stable isotopes (δ18O and δ2H values reveal the recharge sources of groundwater in the multilayered aquifer system. The unconfined groundwater originates from local modern precipitation; the confined groundwater in mainland originates from modern precipitation in northwestern mountain area, and the confined groundwater in Donghai and Leizhou is sourced from rainfall recharge during an older period with a colder climate. Ionic relations demonstrate that silicate weathering, carbonate dissolutions, and cation exchange are the primary processes controlling the groundwater chemical composition. Declining trends of groundwater level and increasing trends of TDS of the confined groundwater in islands reveal the landward extending tendency of the freshwater-seawater mixing zone.

Coastal Aquifer Contamination and Geochemical Processes Evaluation in Tugela Catchment, South Africa—Geochemical and Statistical Approaches

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Badana Ntanganedzeni

2018-05-01

Full Text Available Assessment of groundwater quality, contamination sources and geochemical processes in the coastal aquifer of Tugela Catchment, South Africa were carried out by the geochemical and statistical approach using major ion chemistry of 36 groundwater samples. Results suggest that the spatial distribution pattern of EC, TDS, Na, Mg, Cl and SO4 are homogenous and elevated concentrations are observed in the wells in the coastal region and few wells near the Tugela River. Wells located far from the coast are enriched by Ca, HCO3 and CO3. Durov diagrams, Gibbs plots, ionic ratios, chloro alkaline indices (CAI1 and CAI2 and correlation analysis imply that groundwater chemistry in the coastal aquifer of Tugela Catchment is regulated by the ion exchange, mineral dissolution, saline sources, and wastewater infiltration from domestic sewage; septic tank leakage and irrigation return flow. Principle component analysis also ensured the role of saline and anthropogenic sources and carbonates dissolution on water chemistry. Spatial distributions of factor score also justify the above predictions. Groundwater suitability assessment indicates that around 80% and 90% of wells exceeded the drinking water standards recommended by the WHO and South African drinking water standards (SAWQG, respectively. Based on SAR, RSC, PI, and MH classifications, most of the wells are suitable for irrigation in the study region. USSL classification suggests that groundwater is suitable for coarse-textured soils and salt-tolerant crops. The study recommends that a proper management plan is required to protect this coastal aquifer efficiently.

Consequences and mitigation of saltwater intrusion induced by short-circuiting during aquifer storage and recovery in a coastal subsurface

Science.gov (United States)

Gerardus Zuurbier, Koen; Stuyfzand, Pieter Jan

2017-02-01

Coastal aquifers and the deeper subsurface are increasingly exploited. The accompanying perforation of the subsurface for those purposes has increased the risk of short-circuiting of originally separated aquifers. This study shows how this short-circuiting negatively impacts the freshwater recovery efficiency (RE) during aquifer storage and recovery (ASR) in coastal aquifers. ASR was applied in a shallow saltwater aquifer overlying a deeper, confined saltwater aquifer, which was targeted for seasonal aquifer thermal energy storage (ATES). Although both aquifers were considered properly separated (i.e., a continuous clay layer prevented rapid groundwater flow between both aquifers), intrusion of deeper saltwater into the shallower aquifer quickly terminated the freshwater recovery. The presumable pathway was a nearby ATES borehole. This finding was supported by field measurements, hydrochemical analyses, and variable-density solute transport modeling (SEAWAT version 4; Langevin et al., 2007). The potentially rapid short-circuiting during storage and recovery can reduce the RE of ASR to null. When limited mixing with ambient groundwater is allowed, a linear RE decrease by short-circuiting with increasing distance from the ASR well within the radius of the injected ASR bubble was observed. Interception of deep short-circuiting water can mitigate the observed RE decrease, although complete compensation of the RE decrease will generally be unattainable. Brackish water upconing from the underlying aquitard towards the shallow recovery wells of the ASR system with multiple partially penetrating wells (MPPW-ASR) was observed. This leakage may lead to a lower recovery efficiency than based on current ASR performance estimations.

Hydrogeological geochemical and isotopic study of the coastal aquifer of Sousse Eastern, Tunisia

International Nuclear Information System (INIS)

Ben-Hamouda, M. F.; Carreira, P.; Marques, J. M.; Eggenkamp, H.

2012-12-01

At Sahel, near one of the seaside resort available in Tunisia, the water quantity and quality is a major problem ever at southern center of Tunisia. The Oued Laya coastal system is no exception. The levels, a shallow aquifer up to depths of about 60 m whose reservoir is mainly formed by Mio-Pliocnesediments (with some gypsum lenses dispersed within the geological formations) and deep aquifer, situated between 100 and 250 m depth, located in the Miocene sandstone formations. The results of geochemical and isotopic studies have shown that groundwater salinity seems not be linked with the increasing water well's abstraction. In contrast, water mineralization seems to acquired by dissolution of minerals in the aquifer system especially halie and gypsum. Besides ion exchange processes play also an important role in the groundwater mineralization. Therefore, it clearly appears that several sources might contribute with different mineralization to the selenization of the aquifer through the natural recharge and also through the return of water irrigation. The contamination of the Mio-Pliocene shallow aquifer by a mixture with seawater is confirmed, and stable isotopes data do not support the hypothesis of mixing with seawater. (Author)

Preliminary Study Contamination of Organochlorine Pesticide (Heptachlor) and Heavy Metal (Arsenic) in Shallow Groundwater Aquifer of Semarang Coastal Areas

Science.gov (United States)

Rochaddi, Baskoro; Adhi Suryono, Chrisna; Atmodjo, Warsito; Satriadi, Alfi

2018-02-01

The present study was conducted to assess the level of pesticide and heavy metal contamination in shallow aquifer of Semarang coastal areas. Results indicated that Heptachlor and Arsenic were detected in the water samples in the range 0.023-0.055 μg L-1 and 0,03-1,63 μg L-1, respectively. Compared to the standard limits of the organochlorine contents in the water sample by World Health Organization (WHO) limits and Indonesian Drinking and Domestic Water Quality Standard for Ground Water (IWQS), groundwater of Semarang Coastal Areas was contaminated with pesticide and heavy metal. This study has proven the presence of organochlorine and heavy metal contamination of some shallow aquifer supplies in the coastal areas of Semarang.

Integrated assessment of future potential global change scenarios and their hydrological impacts in coastal aquifers – a new tool to analyse management alternatives in the Plana Oropesa-Torreblanca aquifer

Directory of Open Access Journals (Sweden)

D. Pulido-Velazquez

2018-05-01

Full Text Available Any change in the components of the water balance in a coastal aquifer, whether natural or anthropogenic, can alter the freshwater–salt water equilibrium. In this sense climate change (CC and land use and land cover (LULC change might significantly influence the availability of groundwater resources in the future. These coastal systems demand an integrated analysis of quantity and quality issues to obtain an appropriate assessment of hydrological impacts using density-dependent flow solutions. The aim of this work is to perform an integrated analysis of future potential global change (GC scenarios and their hydrological impacts in a coastal aquifer, the Plana Oropesa-Torreblanca aquifer. It is a Mediterranean aquifer that extends over 75 km2 in which important historical LULC changes have been produced and are planned for the future. Future CC scenarios will be defined by using an equi-feasible and non-feasible ensemble of projections based on the results of a multi-criteria analysis of the series generated from several regional climatic models with different downscaling approaches. The hydrological impacts of these CC scenarios combined with future LULC scenarios will be assessed with a chain of models defined by a sequential coupling of rainfall-recharge models, crop irrigation requirements and irrigation return models (for the aquifer and its neighbours that feed it, and a density-dependent aquifer approach. This chain of models, calibrated using the available historical data, allow testing of the conceptual approximation of the aquifer behaviour. They are also fed with series representatives of potential global change scenarios in order to perform a sensitivity analysis regarding future scenarios of rainfall recharge, lateral flows coming from the hydraulically connected neighbouring aquifer, agricultural recharge (taking into account expected future LULC changes and sea level rise (SLR. The proposed analysis is valuable for

Assessment of groundwater availability in the Northern Atlantic Coastal Plain aquifer system From Long Island, New York, to North Carolina

Science.gov (United States)

Masterson, John P.; Pope, Jason P.; Fienen, Michael N.; Monti, Jr., Jack; Nardi, Mark R.; Finkelstein, Jason S.

2016-08-31

Executive SummaryThe U.S. Geological Survey began a multiyear regional assessment of groundwater availability in the Northern Atlantic Coastal Plain (NACP) aquifer system in 2010 as part of its ongoing regional assessments of groundwater availability of the principal aquifers of the Nation. The goals of this national assessment are to document effects of human activities on water levels and groundwater storage, explore climate variability effects on the regional water budget, and provide consistent and integrated information that is useful to those who use and manage the groundwater resource. As part of this nationwide assessment, the USGS evaluated available groundwater resources within the NACP aquifer system from Long Island, New York, to northeastern North Carolina.The northern Atlantic Coastal Plain physiographic province depends heavily on groundwater to meet agricultural, industrial, and municipal needs. The groundwater assessment of the NACP aquifer system included an evaluation of how water use has changed over time; this evaluation primarily used groundwater budgets and development of a numerical modeling tool to assess system responses to stresses from future human uses and climate trends.This assessment focused on multiple spatial and temporal scales to examine changes in groundwater pumping, storage, and water levels. The regional scale provides a broad view of the sources and demands on the system with time. The sub-regional scale provides an evaluation of the differing response of the aquifer system across geographic areas allowing for closer examination of the interaction between different aquifers and confining units and the changes in these interactions under pumping and recharge conditions in 2013 and hydrologic stresses as much as 45 years in the future. By focusing on multiple scales, water-resource managers may utilize this study to understand system response to changes as they affect the system as a whole.The NACP aquifer system extends from

Reaction of subsurface coastal aquifers to climate and land use changes in Greece: modelling of groundwater refreshening patterns under natural recharge conditions

Science.gov (United States)

Lambrakis, N.; Kallergis, G.

2001-05-01

This paper studies the multicomponent ion exchange process and freshening time under natural recharge conditions for three coastal aquifers in Greece. Due to over-pumping and the dry years of 1980-1990 decline in groundwater quality has been observed in most of the Greek coastal aquifers. This decline is caused by a lack of reliable water resource management, water abstraction from great depths, and seawater intrusion resulting in a rise of the fresh/salt water interface (salinisation process) due to a negative water balance. The reverse phenomenon, which should lead to groundwater freshening, is a long process. The freshening process shows chromatographic patterns that are due to chemical reactions such as calcite dissolution and cation exchange, and simultaneously occurring transport and dispersion processes. Using the geochemical simulation codes PHREEQE and PHREEQM (Parkhurst et al., US Geol. Surv. Water Resour. Invest., 80-96 (1980) 210; Appelo and Postma, Geochemistry, Groundwater and Pollution (1994)), these patterns were analysed and the above-mentioned processes were simulated for carefully selected aquifers in Peloponnesus and Crete (Greece). Aquifers of the Quaternary basin of Glafkos in Peloponnesus, the Neogene formations in Gouves, Crete, and the carbonate aquifer of Malia, Crete, were examined as representative examples of Greek coastal aquifer salinisation. The results show that when pumping was discontinued, the time required for freshening under natural conditions of the former two aquifers is long and varies between 8000 and 10,000 years. The Malia aquifer on the other hand, has a freshening time of 15 years. Freshening time was shown to depend mainly on cation exchange capacities and the recharge rate of the aquifers.

Summary of hydrologic testing of the Floridan aquifer system at Fort Stewart, coastal Georgia, 2009-2010

Science.gov (United States)

Gonthier, Gerald J.

2011-01-01

Two test wells were completed at Fort Stewart, coastal Georgia, to investigate the potential for using the Lower Floridan aquifer as a source of water to satisfy anticipated, increased water needs. The U.S. Geological Survey, in cooperation with the U.S. Department of the Army, completed hydrologic testing of the Floridan aquifer system at the study site, including flowmeter surveys, slug tests, and 24- and 72-hour aquifer tests by mid-March 2010. Analytical approaches and model simulation were applied to aquifer-test results to provide estimates of transmissivity and hydraulic conductivity of the multilayered Floridan aquifer system. Data from a 24-hour aquifer test of the Upper Floridan aquifer were evaluated by using the straight-line Cooper-Jacob analytical method. Data from a 72-hour aquifer test of the Lower Floridan aquifer were simulated by using axisymmetric model simulations. Results of aquifer testing indicated that the Upper Floridan aquifer has a transmissivity of 100,000 feet-squared per day, and the Lower Floridan aquifer has a transmissivity of 7,000 feet-squared per day. A specific storage for the Floridan aquifer system as a result of model calibration was 3E-06 ft–1. Additionally, during a 72-hour aquifer test of the Lower Floridan aquifer, a drawdown response was observed in two Upper Floridan aquifer wells, one of which was more than 1 mile away from the pumped well.

Geochemical approach of the salinization mechanisms of coastal aquifers - 14C - 226Ra chronologies

International Nuclear Information System (INIS)

Barbecot, F.

1999-11-01

Through time, coastal aquifers which constitute a great part of available fresh water resources from sedimentary basins in France, were submitted to changes in hydraulic gradients and hydrodynamic properties mainly due to discharge/recharge phases in response to sea level variations and/or anthropic forcing. Performed in the framework of the European program PALAEAUX ('Management of coastal aquifers in Europe, paleo-waters and natural controls'), this work aimed to understand the salinization process originating from the recharge/discharge conditions and recognized in three study aquifers: the calcareous Dogger aquifers along the Channel (Caen area), and the Atlantic coast (Marais Poitevin), and the Astian sandy aquifer (Cap d'Agde). Besides the conventional hydrogeological and hydrochemical methods, the main tools used are those of isotope geochemistry. For the three sites, the modern, fresh groundwaters are marked by the anthropisation of the recharge area. The evolution of isotopic signatures along a flow path depending on the mineralogy of the aquifer matrix, is linked to water-rock interactions such as cation exchange, and equilibrium with aluminosilicates. For the three study sites, the modern fresh groundwaters are marked by the anthropisation of the recharge area. The evolution of isotopic signatures along a flow path depending on the mineralogy of the aquifer matrix, is linked to water-rock interactions such as cation exchange, and equilibrium with aluminosilicates. Residence times of these fresh groundwater are from Present (Atlantic site) up to the 14 C detection limit (Channel site). Groundwater of the Astian aquifer belongs to Holocene, as determined by both 14 C and 226 Ra. From Present to 3 ka, 14 C and 226 Ra ages are coherent. Beyond, the discrepancy observed can be associated to the under-estimation of in- situ 226 Ra production, but more likely, to the 'buffer' effect of the matrix with respect to the 14 C isotopic equilibration. The salty waters

Sea-level rise impacts on seawater intrusion in coastal aquifers: Review and integration

Science.gov (United States)

Ketabchi, Hamed; Mahmoodzadeh, Davood; Ataie-Ashtiani, Behzad; Simmons, Craig T.

2016-04-01

Sea-level rise (SLR) influences groundwater hydraulics and in particular seawater intrusion (SWI) in many coastal aquifers. The quantification of the combined and relative impacts of influential factors on SWI has not previously been considered in coastal aquifers. In the present study, a systematic review of the available literature on this topic is first provided. Then, the potential remaining challenges are scrutinized. Open questions on the effects of more realistic complexities such as gradual SLR, parameter uncertainties, and the associated influences in decision-making models are issues requiring further investigation. We assess and quantify the seawater toe location under the impacts of SLR in combination with recharge rate variations, land-surface inundation (LSI) due to SLR, aquifer bed slope variation, and changing landward boundary conditions (LWBCs). This is the first study to include all of these factors in a single analysis framework. Both analytical and numerical models are used for these sensitivity assessments. It is demonstrated that (1) LSI caused by SLR has a significant incremental impact on the seawater toe location, especially in the flatter coasts and the flux-controlled (FC) LWBCs, however this impact is less than the reported orders of magnitude differences which were estimated using only analytical solutions; (2) LWBCs significantly influence the SLR impacts under almost all conditions considered in this study; (3) The main controlling factors of seawater toe location are the magnitudes of fresh groundwater discharge to sea and recharge rate. Regional freshwater flux entering from the landward boundary and the groundwater hydraulic gradient are the major contributors of fresh groundwater discharge to sea for both FC and head-controlled (HC) systems, respectively; (4) A larger response of the aquifer and larger seawater toe location changes are demonstrable for a larger ratio of the aquifer thickness to the aquifer length particularly in

Use of time series and harmonic constituents of tidal propagation to enhance estimation of coastal aquifer heterogeneity

Science.gov (United States)

Hughes, Joseph D.; White, Jeremy T.; Langevin, Christian D.

2010-01-01

A synthetic two‐dimensional model of a horizontally and vertically heterogeneous confined coastal aquifer system, based on the Upper Floridan aquifer in south Florida, USA, subjected to constant recharge and a complex tidal signal was used to generate 15‐minute water‐level data at select locations over a 7‐day simulation period.   “Observed” water‐level data were generated by adding noise, representative of typical barometric pressure variations and measurement errors, to 15‐minute data from the synthetic model. Permeability was calibrated using a non‐linear gradient‐based parameter inversion approach with preferred‐value Tikhonov regularization and 1) “observed” water‐level data, 2) harmonic constituent data, or 3) a combination of “observed” water‐level and harmonic constituent data.    In all cases, high‐frequency data used in the parameter inversion process were able to characterize broad‐scale heterogeneities; the ability to discern fine‐scale heterogeneity was greater when harmonic constituent data were used.  These results suggest that the combined use of highly parameterized‐inversion techniques and high frequency time and/or processed‐harmonic constituent water‐level data could be a useful approach to better characterize aquifer heterogeneities in coastal aquifers influenced by ocean tides.

Controls on Nitrous Oxide Production in, and Fluxes from a Coastal Aquifer in Long Island, NY, USA

Directory of Open Access Journals (Sweden)

Caitlin Young

2016-11-01

Full Text Available Nitrous oxide (N2O has 265 times greater greenhouse potential than carbon dioxide and its atmospheric concentration has increased by about 20% since industrialization; however, N2O production and emissions from aquatic systems are poorly constrained. To evaluate N2O fluxes associated with meteoric groundwater discharge to coastal zones, we measured N2O concentrations in May and October 2011 from two discharge points of the Upper Glacial aquifer on Long Island, NY, USA. One coastal zone contains only fresh water and the other contains an upper saline zone. N2O concentrations decreased by around 40% for the fresh water and a factor of two for the salt water from May to October, 2011. Fluxes were around 100 to 200 times greater from the freshwater (246 to 448 µmol/m shoreline/day than saltwater aquifer (26.1 to 26.5 µmol/m shoreline/day. N2O concentrations correlate positively with NO3− and dissolved oxygen concentrations and negatively with salinity, dissolved organic carbon (DOC and N2 denitrification concentrations. The smaller saltwater N2O export resulted from DOC enrichment in the upper saline zone, which appears to have driven denitrification to completion, removed N2O, and increased N2 denitrification. DOC concentrations should be considered in global N2O flux estimates for coastal aquifers.

The quality of our Nation's waters: water quality in the Mississippi embayment-Texas coastal uplands aquifer system and Mississippi River Valley alluvial aquifer, south-central United States, 1994-2008

Science.gov (United States)

Kingsbury, James A.; Barlow, Jeannie R.; Katz, Brian G.; Welch, Heather L.; Tollett, Roland W.; Fahlquist, Lynne S.

2015-01-01

About 8 million people rely on groundwater from the Mississippi embayment—Texas coastal uplands aquifer system for drinking water. The Mississippi River Valley alluvial aquifer also provides drinking water for domestic use in rural areas but is of primary importance to the region as a source of water for irrigation. Irrigation withdrawals from this aquifer are among the largest in the Nation and play a key role in the economy of the area, where annual crop sales total more than $7 billion. The reliance of the region on both aquifers for drinking water and irrigation highlights the importance of long-term management to sustain the availability and quality of these resources.

LCA Applications

DEFF Research Database (Denmark)

Owsianiak, Mikołaj; Bjørn, Anders; Laurent, Alexis

2018-01-01

The chapter gives examples of applications of LCA by the central societal actors in government, industry and citizens, and discusses major motivations and challenges for the use of LCA to support science-based decision-making from their respective perspectives. We highlight applications of LCA...... environmental impacts of products and systems and support decisions around production and consumption and highlights factors that prevent its even more widespread application....

Assessing the recharge of a coastal aquifer using physical observations, tritium, groundwater chemistry and modelling.

Science.gov (United States)

Santos, Isaac R; Zhang, Chenming; Maher, Damien T; Atkins, Marnie L; Holland, Rodney; Morgenstern, Uwe; Li, Ling

2017-02-15

Assessing recharge is critical to understanding groundwater and preventing pollution. Here, we investigate recharge in an Australian coastal aquifer using a combination of physical, modelling and geochemical techniques. We assess whether recharge may occur through a pervasive layer of floodplain muds that was initially hypothesized to be impermeable. At least 59% of the precipitation volume could be accounted for in the shallow aquifer using the water table fluctuation method during four significant recharge events. Precipitation events rates were estimated in the area underneath the floodplain clay layer rather than in the sandy area. A steady-state chloride method implied recharge rates of at least 200mm/year (>14% of annual precipitation). Tritium dating revealed long term net vertical recharge rates ranging from 27 to 114mm/year (average 58mm/year) which were interpreted as minimum net long term recharge. Borehole experiments revealed more permeable conditions and heterogeneous infiltration rates when the floodplain soils were dry. Wet conditions apparently expand floodplain clays, closing macropores and cracks that act as conduits for groundwater recharge. Modelled groundwater flow paths were consistent with tritium dating and provided independent evidence that the clay layer does not prevent local recharge. Overall, all lines of evidence demonstrated that the coastal floodplain muds do not prevent the infiltration of rainwater into the underlying sand aquifer, and that local recharge across the muds was widespread. Therefore, assuming fine-grained floodplain soils prevent recharge and protect underlying aquifers from pollution may not be reasonable. Copyright © 2016 Elsevier B.V. All rights reserved.

LCA and Sustainability

DEFF Research Database (Denmark)

Moltesen, Andreas; Bjørn, Anders

2018-01-01

LCA is often presented as a sustainability assessment tool. This chapter analyses the relationship between LCA and sustainability. This is done by first outlining the history of the sustainability concept, which gained momentum with the Brundtland Commission’s report ‘Our Common Future report...... is then demonstrated, and the strategy of LCA to achieving environmental protection, namely to guide the reduction of environmental impacts per delivery of a function, is explained. The attempt to broaden the scope of LCA, beyond environmental protection, by so-called life cycle sustainability assessment (LCSA......) is outlined. Finally, the limitations of LCA in guiding a sustainable development are discussed....

Seasonal variation in natural recharge of coastal aquifers

Science.gov (United States)

Mollema, Pauline N.; Antonellini, Marco

2013-06-01

Many coastal zones around the world have irregular precipitation throughout the year. This results in discontinuous natural recharge of coastal aquifers, which affects the size of freshwater lenses present in sandy deposits. Temperature data for the period 1960-1990 from LocClim (local climate estimator) and those obtained from the Intergovernmental Panel on Climate Change (IPCC) SRES A1b scenario for 2070-2100, have been used to calculate the potential evapotranspiration with the Thornthwaite method. Potential recharge (difference between precipitation and potential evapotranspiration) was defined at 12 locations: Ameland (The Netherlands), Auckland and Wellington (New Zealand); Hong Kong (China); Ravenna (Italy), Mekong (Vietnam), Mumbai (India), New Jersey (USA), Nile Delta (Egypt), Kobe and Tokyo (Japan), and Singapore. The influence of variable/discontinuous recharge on the size of freshwater lenses was simulated with the SEAWAT model. The discrepancy between models with continuous and with discontinuous recharge is relatively small in areas where the total annual recharge is low (258-616 mm/year); but in places with Monsoon-dominated climate (e.g. Mumbai, with recharge up to 1,686 mm/year), the difference in freshwater-lens thickness between the discontinuous and the continuous model is larger (up to 5 m) and thus important to consider in numerical models that estimate freshwater availability.

Geochemistry of shallow ground water in coastal plain environments in the southeastern United States: implications for aquifer susceptibility

International Nuclear Information System (INIS)

Tesoriero, Anthony J.; Spruill, Timothy B.; Eimers, Jo L.

2004-01-01

Ground-water chemistry data from coastal plain environments have been examined to determine the geochemical conditions and processes that occur in these areas and assess their implications for aquifer susceptibility. Two distinct geochemical environments were studied to represent a range of conditions: an inner coastal plain setting having more well-drained soils and lower organic carbon (C) content and an outer coastal plain environment that has more poorly drained soils and high organic C content. Higher concentrations of most major ions and dissolved inorganic and organic C in the outer coastal plain setting indicate a greater degree of mineral dissolution and organic matter oxidation. Accordingly, outer coastal plain waters are more reducing than inner coastal plain waters. Low dissolved oxygen (O 2 ) and nitrate (NO 3 - ) concentrations and high iron (Fe) concentrations indicate that ferric iron (Fe (III)) is an important electron acceptor in this setting, while dissolved O 2 is the most common terminal electron acceptor in the inner coastal plain setting. The presence of a wide range of redox conditions in the shallow aquifer system examined here underscores the importance of providing a detailed geochemical characterization of ground water when assessing the intrinsic susceptibility of coastal plain settings. The greater prevalence of aerobic conditions in the inner coastal plain setting makes this region more susceptible to contamination by constituents that are more stable under these conditions and is consistent with the significantly (p 3 - found in this setting. Herbicides and their transformation products were frequently detected (36% of wells sampled), however concentrations were typically low (<0.1 μg/L). Shallow water table depths often found in coastal plain settings may result in an increased risk of the detection of pesticides (e.g., alachlor) that degrade rapidly in the unsaturated zone

Mapping of coastal aquifer vulnerable zone in the south west coast of Kanyakumari, South India, using GIS-based DRASTIC model.

Science.gov (United States)

Kaliraj, S; Chandrasekar, N; Peter, T Simon; Selvakumar, S; Magesh, N S

2015-01-01

The south west coast of Kanyakumari district in Tamil Nadu, India, is significantly affected by seawater intrusion and diffusion of pollutants into the aquifers due to unregulated beach placer mining and other anthropogenic activities. The present study investigates the vulnerability of the coastal aquifers using Geographic Information System (GIS)-based DRASTIC model. The seven DRASTIC parameters have been analyzed using the statistical equation of this model to demarcate the vulnerable zones for aquifer contamination. The vulnerability index map is prepared from the weighted spatial parameters, and an accounting of total index value ranged from 85 to 213. Based on the categorization of vulnerability classes, the high vulnerable zones are found near the beach placer mining areas between Manavalakurichi and Kodimanal coastal stretches. The aquifers associated with settlements and agricultural lands in the middle-eastern part have experienced high vulnerability due to contaminated water bodies. Similarly, the coastal areas of Thengapattinam and Manakudi estuary and around the South Tamaraikulam have also been falling under high vulnerability condition due to backwater and saltpan. In general, the nearshore region except the placer mining zone and the backwater has a moderately vulnerable condition, and the vulnerability index values range from 149 to180. Significantly, the northern and northeastern uplands and some parts of deposition zones in the middle-south coast have been identified as low to no vulnerable conditions. They are structurally controlled by various geological features such as charnockite, garnet biotite gneiss and granites, and sand dunes, respectively. The aquifer vulnerability assessment has been cross-verified by geochemical indicators such as total dissolved solids (TDS), Cl(-), HCO₃(-), and Cl(-)/HCO₃(-) ratio. The high ranges of TDS (1,842--3,736 mg/l) and Cl(-) (1,412--2,112 mg/l) values are well correlated with the observed high

Spatial Distribution of Field Physico-Chemical Parameters in the Vulcano Island (Italy) Coastal Aquifer: Volcanological and Hydrogeological Implications

OpenAIRE

Paolo Madonia; Giorgio Capasso; Rocco Favara; Salvatore Francofonte; Paolo Tommasi

2015-01-01

Vulcano, the southernmost of the Aeolian island arc (Italy), is characterized by a shallow coastal aquifer resulting from the mixing of seawater, meteoric recharge and volcanogenic fluids. The aquifer has been intensively studied during the last decades, but a comprehensive hydrogeological model has never been developed due to the lack of direct information about the litho-stratigraphic columns of the wells and the depth of water bearing levels. We present and discuss here the ...

Emerging role of Geographical Information System (GIS), Life Cycle Assessment (LCA) and spatial LCA (GIS-LCA) in sustainable bioenergy planning.

Science.gov (United States)

Hiloidhari, Moonmoon; Baruah, D C; Singh, Anoop; Kataki, Sampriti; Medhi, Kristina; Kumari, Shilpi; Ramachandra, T V; Jenkins, B M; Thakur, Indu Shekhar

2017-10-01

Sustainability of a bioenergy project depends on precise assessment of biomass resource, planning of cost-effective logistics and evaluation of possible environmental implications. In this context, this paper reviews the role and applications of geo-spatial tool such as Geographical Information System (GIS) for precise agro-residue resource assessment, biomass logistic and power plant design. Further, application of Life Cycle Assessment (LCA) in understanding the potential impact of agro-residue bioenergy generation on different ecosystem services has also been reviewed and limitations associated with LCA variability and uncertainty were discussed. Usefulness of integration of GIS into LCA (i.e. spatial LCA) to overcome the limitations of conventional LCA and to produce a holistic evaluation of the environmental benefits and concerns of bioenergy is also reviewed. Application of GIS, LCA and spatial LCA can help alleviate the challenges faced by ambitious bioenergy projects by addressing both economics and environmental goals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of a Changing Climate on Seasonal Variation in Natural Recharge of Unconfined Coastal Aquifers

Science.gov (United States)

Antonellini, Marco; Nella Mollema, Pauline

2013-04-01

Irregular rainfall patterns throughout the year result in the discontinuous natural recharge of coastal aquifers, which has an effect on the size of freshwater lenses present in sandy deposits. The thickness of the freshwater lenses is important in the context of farmland salinization and coastal ecosystems survival. This study presents numerical models that simulate continuous and discontinuous recharge in sandy coastal aquifers and the thickness of resulting fresh water lenses under current and future climate scenarios. Temperature data for the period 1960-1990 from LOCCLIM FAO and from the IPCC SRES A1b scenario for 2070-2100, have been used to calculate the potential evapotranspiration. Potential recharge was defined as the difference between the precipitation and potential evapotranspiration in twelve locations around the world: Ameland (The Netherlands), Auckland and Wellington (New Zealand), Hong Kong, Ravenna (Italy), Mekong (Vietnam), Mumbai (India), New Jersey (USA), Nile Delta (Egypt), Kobe and Tokyo (Japan), and Singapore. These locations have shallow coastal aquifers along low lying coasts and comparable aquifer structure, which is the result of similar sediment supply and deposition in the Holocene as well as by the sea level changes from the last ice age to the present time. Particular attention has been paid to temporal variations of natural recharge that can vary from continuous recharge throughout the year to discontinuous recharge. The most dramatic reduction in the magnitude of potential annual recharge by the end of this century will occur at lower latitudes (Mumbai, Singapore, Hong Kong and Mekong). The most pronounced change in length of the dry period occurs for Kobe (Japan) and Singapore even though the total annual amount of recharge remains practically the same. The Influence of variable recharge on the size of freshwater lenses surrounded by saline water is simulated with the SEAWAT model. Models where the recharge is applied

The effects of the 2004 tsunami on a coastal aquifer in Sri Lanka

DEFF Research Database (Denmark)

Vithanage, Meththika Suharshini; Engesgaard, Peter Knudegaard; Villholth, Karen G.

2012-01-01

) of the groundwater were carried out monthly from October 2005 to August 2007. The aquifer system and tsunami saltwater intrusion were modeled using the variable-density flow and solute transport code HST3D to understand the tsunami plume behavior and estimate the aquifer recovery time. EC values reduced as a result...... on groundwater in coastal areas. Field investigations on the east coast of Sri Lanka were carried out along a transect located perpendicular to the coastline on a 2.4 km wide sand stretch bounded by the sea and a lagoon. Measurements of groundwater table elevation and electrical conductivity (EC...... of the monsoonal rainfall following the tsunami with a decline in reduction rate during the dry season. The upper part of the saturated zone (down to 2.5 m) returned to freshwater conditions (EC

Hydrogeology and groundwater evaluation of a shallow coastal aquifer, southern Akwa Ibom State (Nigeria)

Science.gov (United States)

Edet, Aniekan

2017-09-01

The rapid expansion of economic activities in coastal parts of Nigeria has triggered an uncoordinated development of groundwater leading to stress on the resource. Hence a study was conducted to assess the hydrogeological characteristics of the shallow coastal aquifer of southern Akwa Ibom State, Nigeria. Emphasis was on the hydraulic characteristics, quality with respect to domestic and irrigation purposes and influence of seawater. The study result revealed that the aquifer consist of intercalations of clayey sand and sand. The aquifer is characterized by high hydraulic conductivity and transmissivity values. The groundwater flow direction is southwards with higher groundwater depletion in the dry season. Groundwater samples from hand dug wells and boreholes were evaluated based on World Health Organization standard and some indices, respectively, for drinking and irrigation uses. The groundwaters are fit for drinking and domestic uses. However, more than 70 % of the pH values are not within the allowable limits of between 6.5 and 9.2 for drinking and domestic use. Therefore, it is recommended that neutralizing filter containing calcite or ground limestone should be applied to raise the pH of the groundwater. Of the 10 parameters used to assess the water for irrigation use, only sodium adsorption ratio (SAR), magnesium hazard (MH) and magnesium ratio indicated the excellent quality of these waters. Na+-K+-HCO3 - constitute the dominant water type. Total dissolved solids and ratios of Na+/Cl-, Mg2+/Cl-, and Ca2+/SO4 2- and saltwater mixing index (SMI) suggest some level of seawater intrusion in the area.

Residence times of groundwater and nitrate transport in coastal aquifer systems: Daweijia area, northeastern China.

Science.gov (United States)

Han, Dongmei; Cao, Guoliang; McCallum, James; Song, Xianfang

2015-12-15

Groundwater within the coastal aquifer systems of the Daweijia area in northeastern China is characterized by a large of variations (33-521mg/L) in NO3(-) concentrations. Elevated nitrate concentrations, in addition to seawater intrusion in the Daweijia well field, both attributable to anthropogenic activities, may impact future water-management practices. Chemical and stable isotopic (δ(18)O, δ(2)H) analysis, (3)H and CFCs methods were applied to provide a better understanding of the relationship between the distribution of groundwater mean residence time (MRT) and nitrate transport, and to identify sources of nitrate concentrations in the complex coastal aquifer systems. There is a relatively narrow range of isotopic composition (ranging from -8.5 to -7.0‰) in most groundwater. Generally higher tritium contents observed in the wet season relative to the dry season may result from rapid groundwater circulation in response to the rainfall through the preferential flow paths. In the well field, the relatively increased nitrate concentrations of groundwater, accompanied by the higher tritium contents in the wet season, indicate the nitrate pollution can be attributed to domestic wastes. The binary exponential and piston-flow mixing model (BEP) yielded feasible age distributions based on the conceptual model. The good inverse relationship between groundwater MRTs (92-467years) and the NO3(-) concentrations in the shallow Quaternary aquifers indicates that elevated nitrate concentrations are attributable to more recent recharge for shallow groundwater. However, there is no significant relationship between the MRTs (8-411years) and the NO3(-) concentrations existing in the carbonate aquifer system, due to the complex hydrogeological conditions, groundwater age distributions and the range of contaminant source areas. Nitrate in the groundwater system without denitrification effects could accumulate and be transported for tens of years, through the complex carbonate

Managed Aquifer Recharge Using Treated Wastewater: An Option to Manage a Coastal Aquifer In Oman For Better Domestic Water Supply

Science.gov (United States)

Al-Maktoumi, Ali; Zekri, Slim; ElRawy, Mustafa

2016-04-01

Arid countries, such as the Sultanate of Oman, are facing challenges of water shortages threatening economic development and social stability. Most of those countries are vulnerable to the potential adverse impacts of climate change, the most significant of which are increased average temperatures, less and more erratic precipitation, sea level rise, and desertification. The combined effect of existing adverse conditions and likely impacts of future climate change will make water management even more difficult than what it is today. Tremendous efforts have been devoted to augment the water resources. Managed Aquifer Recharge (MAR) is practiced widely to store water during periods of surpluses and withdraw during deficits from an aquifer. In Muscat, there will be a surplus of >100,000 m3/day of TWW during winter months in the coming few years. The aquifer along the northern coast of Oman (Al-Khawd Aquifer) is conducive for MAR. Data show that TWW volumes will increase from 7.6 Mm3 in 2003 to 70.9 Mm3 in 2035 in Muscat city only. This study assesses, using MODFLOW 2005 numerical code, the impact of MAR using TWW on better management of the Al-Khawd unconfined coastal aquifer for better urban water supply. Specifically, aiming to maximize withdrawals from the domestic wells with minimize adverse effect of seawater intrusion. The model operates under a number of constrains that minimize the loss to the sea and the injected TWW must not migrates upstream (due to developed mound) and reach the wellfields used for domestic supply. The hypothetical injection wells are located downstream the domestic wellfield zone. The results of different managerial scenarios show that MAR produces a hydraulic barrier that decelerates the seawater intrusion which allows higher abstraction of pristine water from the upstream part of the aquifer. MAR along with redistribution/relocation of public wells allows abstraction of 2 times the current abstraction rate (around 6 Mm3/year to 12 Mm3

Numerical modeling and sensitivity analysis of seawater intrusion in a dual-permeability coastal karst aquifer with conduit networks

Directory of Open Access Journals (Sweden)

Z. Xu

2018-01-01

Full Text Available Long-distance seawater intrusion has been widely observed through the subsurface conduit system in coastal karst aquifers as a source of groundwater contaminant. In this study, seawater intrusion in a dual-permeability karst aquifer with conduit networks is studied by the two-dimensional density-dependent flow and transport SEAWAT model. Local and global sensitivity analyses are used to evaluate the impacts of boundary conditions and hydrological characteristics on modeling seawater intrusion in a karst aquifer, including hydraulic conductivity, effective porosity, specific storage, and dispersivity of the conduit network and of the porous medium. The local sensitivity analysis evaluates the parameters' sensitivities for modeling seawater intrusion, specifically in the Woodville Karst Plain (WKP. A more comprehensive interpretation of parameter sensitivities, including the nonlinear relationship between simulations and parameters, and/or parameter interactions, is addressed in the global sensitivity analysis. The conduit parameters and boundary conditions are important to the simulations in the porous medium because of the dynamical exchanges between the two systems. The sensitivity study indicates that salinity and head simulations in the karst features, such as the conduit system and submarine springs, are critical for understanding seawater intrusion in a coastal karst aquifer. The evaluation of hydraulic conductivity sensitivity in the continuum SEAWAT model may be biased since the conduit flow velocity is not accurately calculated by Darcy's equation as a function of head difference and hydraulic conductivity. In addition, dispersivity is no longer an important parameter in an advection-dominated karst aquifer with a conduit system, compared to the sensitivity results in a porous medium aquifer. In the end, the extents of seawater intrusion are quantitatively evaluated and measured under different scenarios with the variabilities of

Death Valley Lower Carbonate Aquifer Monitoring Program Wells Down gradient of the Proposed Yucca Mountain Nuclear Waste Repository

International Nuclear Information System (INIS)

Inyo County

2006-01-01

Inyo County has participated in oversight activities associated with the Yucca Mountain Nuclear Waste Repository since 1987. The overall goal of these studies are the evaluation of far-field issues related to potential transport, by ground water, or radionuclides into Inyo County, including Death Valley, and the evaluation of a connection between the Lower Carbonate Aquifer (LCA) and the biosphere. Our oversight and completed Cooperative Agreement research, and a number of other investigators research indicate that there is groundwater flow between the alluvial and carbonate aquifers both at Yucca Mountain and in Inyo County. In addition to the potential of radionuclide transport through the LCA, Czarnecki (1997), with the US Geological Survey, research indicate potential radionuclide transport through the shallower Tertiary-age aquifer materials with ultimate discharge into the Franklin Lake Playa in Inyo County. The specific purpose of this Cooperative Agreement drilling program was to acquire geological, subsurface geology, and hydrologic data to: (1) establish the existence of inter-basin flow between the Amargosa Basin and Death Valley Basin; (2) characterize groundwater flow paths in the LCA through Southern Funeral Mountain Range, and (3) Evaluation the hydraulic connection between the Yucca Mountain repository and the major springs in Death Valley through the LCA

LCA History

DEFF Research Database (Denmark)

Bjørn, Anders; Owsianiak, Mikołaj; Molin, Christine

2018-01-01

The idea of LCA was conceived in the 1960s when environmental degradation and in particular the limited access to resources started becoming a concern. This chapter gives a brief summary of the history of LCA since then with a focus on the fields of methodological development, application...

Hydrogeology and hydrologic conditions of the Northern Atlantic Coastal Plain aquifer System from Long Island, New York, to North Carolina

Science.gov (United States)

Masterson, John P.; Pope, Jason P.; Monti, Jack; Nardi, Mark R.; Finkelstein, Jason S.; McCoy, Kurt J.

2013-11-14

The seaward-dipping sedimentary wedge that underlies the Northern Atlantic Coastal Plain forms a complex groundwater system. This major source of water provides for public and domestic supply and serves as a vital source of freshwater for industrial and agricultural uses throughout the region. Population increases and land-use and climate changes, however, have led to competing demands for water. The regional response of the aquifer system to these stresses poses regional challenges for water-resources management at the State level because hydrologic effects often extend beyond State boundaries. In response to these challenges, the U.S. Geological Survey Groundwater Resources Program began a regional assessment of the groundwater availability of the Northern Atlantic Coastal Plain aquifer system in 2010.

Main Characteristics of LCA

DEFF Research Database (Denmark)

Bjørn, Anders; Owsianiak, Mikołaj; Molin, Christine

2017-01-01

Life cycle assessment (LCA) has a number of defining characteristics that enables it to address questions that no other assessment tools can address. This chapter begins by demonstrating how the use of LCA in the late 2000s led to a drastic shift in the dominant perception that biofuels were “green......”, “sustainable” or “carbon neutral”, which led to a change in biofuel policies . This is followed by a grouping of the LCA characteristics into four headlines and an explanation of these: (1) takes a life cycle perspective , (2) covers a broad range of environmental issues, (3) is quantitative, (4) is based...... on science. From the insights of the LCA characteristics we then consider the strengths and limitations of LCA and end the chapter by listing 10 questions that LCA can answer and 3 that it cannot....

Impact of climate change on freshwater resources in a heterogeneous coastal aquifer of Bremerhaven, Germany: A three-dimensional modeling study.

Science.gov (United States)

Yang, Jie; Graf, Thomas; Ptak, Thomas

2015-01-01

Climate change is expected to induce sea level rise in the German Bight, which is part of the North Sea, Germany. Climate change may also modify river discharge of the river Weser flowing into the German Bight, which will alter both pressure and salinity distributions in the river Weser estuary. To study the long-term interaction between sea level rise, discharge variations, a storm surge and coastal aquifer flow dynamics, a 3D seawater intrusion model was designed using the fully coupled surface-subsurface numerical model HydroGeoSphere. The model simulates the coastal aquifer as an integral system considering complexities such as variable-density flow, variably saturated flow, irregular boundary conditions, irregular land surface and anthropogenic structures (e.g., dyke, drainage canals, water gates). The simulated steady-state groundwater flow of the year 2009 is calibrated using PEST. In addition, four climate change scenarios are simulated based on the calibrated model: (i) sea level rise of 1m, (ii) the salinity of the seaside boundary increases by 4 PSU (Practical Salinity Units), (iii) the salinity of the seaside boundary decreases by 12 PSU, and (iv) a storm surge with partial dyke failure. Under scenarios (i) and (iv), the salinized area expands several kilometers further inland during several years. Natural remediation can take up to 20 years. However, sudden short-term salinity changes in the river Weser estuary do not influence the salinized area in the coastal aquifer. The obtained results are useful for coastal engineering practices and drinking water resource management. Copyright © 2015 Elsevier B.V. All rights reserved.

Contribution of Isotopic Tools to the Numerical Simulation of the Mar del Plata Coastal Aquifer, Argentina

Energy Technology Data Exchange (ETDEWEB)

Bocanegra, E.; Martinez, D. E. [Instituto de Geologia de Costas y del Cuaternario, UNMDP (Argentina); Pool, M.; Carrera, J. [Instituto de Diagnostico Ambiental y Estudios del Agua, CSIC (Spain)

2013-07-15

Over-exploitation in the coastal aquifer in Mar del Plata, Argentina, led to a seawater intrusion process affecting groundwater by salinization. The aim of this paper is to show the contribution of isotopic techniques to generate the numerical flow and transport model of the Mar del Plata aquifer. On the basis of the hydrogeological conceptual model, a numerical model was constructed. It consists of a multilayer aquifer in the urban area with 2 layers separated by an aquitard and a monolayer aquifer in the rest of the basin. The isotopic difference recorded in groundwaters allow the identification of the origin of the recharge and the confirmation of the presence of the hydrogeological environments incorporated in the numerical model. Flow simulation reflects the evolution of piezometric heads. Chloride transport simulation represents the salinization process due to seawater intrusion and the subsequent backward movement of the interface due to the abandonment of salinized wells. The results of numerical simulation confirm the conceptual model and reproduce the impact of the adopted management strategies. (author)

Quantifying aquifer properties and freshwater resource in coastal barriers: a hydrogeophysical approach applied at Sasihithlu (Karnataka state, India)

Science.gov (United States)

Vouillamoz, J.-M.; Hoareau, J.; Grammare, M.; Caron, D.; Nandagiri, L.; Legchenko, A.

2012-11-01

Many human communities living in coastal areas in Africa and Asia rely on thin freshwater lenses for their domestic supply. Population growth together with change in rainfall patterns and sea level will probably impact these vulnerable groundwater resources. Spatial knowledge of the aquifer properties and creation of a groundwater model are required for achieving a sustainable management of the resource. This paper presents a ready-to-use methodology for estimating the key aquifer properties and the freshwater resource based on the joint use of two non-invasive geophysical tools together with common hydrological measurements. We applied the proposed methodology in an unconfined aquifer of a coastal sandy barrier in South-Western India. We jointly used magnetic resonance and transient electromagnetic soundings and we monitored rainfall, groundwater level and groundwater electrical conductivity. The combined interpretation of geophysical and hydrological results allowed estimating the aquifer properties and mapping the freshwater lens. Depending on the location and season, we estimate the freshwater reserve to range between 400 and 700 L m-2 of surface area (± 50%). We also estimate the recharge using time lapse geophysical measurements with hydrological monitoring. After a rainy event close to 100% of the rain is reaching the water table, but the net recharge at the end of the monsoon is less than 10% of the rain. Thus, we conclude that a change in rainfall patterns will probably not impact the groundwater resource since most of the rain water recharging the aquifer is flowing towards the sea and the river. However, a change in sea level will impact both the groundwater reserve and net recharge.

Occurrence and geochemical behavior of arsenic in a coastal aquifer-aquitard system of the Pearl River Delta, China

Energy Technology Data Exchange (ETDEWEB)

Wang, Ya [Department of Earth Sciences, The University of Hong Kong, Hong Kong (China); Jiao, Jiu Jimmy, E-mail: jjiao@hku.hk [Department of Earth Sciences, The University of Hong Kong, Hong Kong (China); Cherry, John A. [School of Engineering, University of Guelph, Guelph, ON, Canada N1G 2W1 (Canada)

2012-06-15

Elevated concentrations of arsenic, up to 161 {mu}g/L, have been identified in groundwater samples from the confined basal aquifer underlying the aquitard of the Pearl River Delta (PRD). Both aquatic arsenic in pore water and solid arsenic in the sediments in the basal aquifer and aquitard were identified. Arsenic speciation of groundwater in the basal aquifer was elucidated on a pH-Eh diagram. In the PRD, arsenic is enriched in groundwater having both low and high salinity, and arsenic enriched groundwater is devoid of dissolved oxygen, has negative Eh values, is slightly alkaline, and has abnormally high concentrations of ammonium and dissolved organic carbon, but low concentrations of nitrate and nitrite. Results of geochemical and hydrochemical analyses and sequential extraction analysis suggest that reductive dissolution of iron oxyhydroxide could be one of the important processes that mobilized solid arsenic. We speculate that mineralization of sedimentary organic matter could also contribute to aquatic arsenic. Scanning electron microscope analysis confirms that abundant authigenic pyrite is present in the sediments. Sulphate derived from paleo-seawater served as the important sulfur source for authigenic pyrite formation. Co-precipitation of arsenic with authigenic pyrite significantly controlled concentrations of aquatic arsenic in the coastal aquifer-aquitard system. - Highlights: Black-Right-Pointing-Pointer Coastal aquifer and aquitard are treated as an integrate system. Black-Right-Pointing-Pointer Both aquatic arsenic and solid arsenic are observed. Black-Right-Pointing-Pointer Aquatic arsenic is derived from reductive dissolution of iron oxyhydroxide. Black-Right-Pointing-Pointer Aquatic arsenic can also derived from mineralization of sedimentary organic matter. Black-Right-Pointing-Pointer Co-precipitation of arsenic with authigenic pyrite is significant in such a system.

Quantifying aquifer properties and freshwater resource in coastal barriers: a hydrogeophysical approach applied at Sasihithlu (Karnataka state, India

Directory of Open Access Journals (Sweden)

J.-M. Vouillamoz

2012-11-01

Full Text Available Many human communities living in coastal areas in Africa and Asia rely on thin freshwater lenses for their domestic supply. Population growth together with change in rainfall patterns and sea level will probably impact these vulnerable groundwater resources. Spatial knowledge of the aquifer properties and creation of a groundwater model are required for achieving a sustainable management of the resource. This paper presents a ready-to-use methodology for estimating the key aquifer properties and the freshwater resource based on the joint use of two non-invasive geophysical tools together with common hydrological measurements.

We applied the proposed methodology in an unconfined aquifer of a coastal sandy barrier in South-Western India. We jointly used magnetic resonance and transient electromagnetic soundings and we monitored rainfall, groundwater level and groundwater electrical conductivity. The combined interpretation of geophysical and hydrological results allowed estimating the aquifer properties and mapping the freshwater lens. Depending on the location and season, we estimate the freshwater reserve to range between 400 and 700 L m⁻² of surface area (± 50%. We also estimate the recharge using time lapse geophysical measurements with hydrological monitoring. After a rainy event close to 100% of the rain is reaching the water table, but the net recharge at the end of the monsoon is less than 10% of the rain. Thus, we conclude that a change in rainfall patterns will probably not impact the groundwater resource since most of the rain water recharging the aquifer is flowing towards the sea and the river. However, a change in sea level will impact both the groundwater reserve and net recharge.

The integrated impacts of natural processes and human activities on the origin and processes of groundwater salinization in the coastal aquifers of Beihai, Southern China

Science.gov (United States)

Li, Q.; Zhan, Y., , Dr; Chen, W. Ms; Yu, S., , Dr

2017-12-01

Salinization in coastal aquifers usually is the results of contamination related to both seawater intrusion and water-rock interaction. The chemical and isotopic methods were combined to identify the origin and processes of groundwater salinization in Daguansha area of Beihai. The concentrations of the major ions that dominate in sea water (Cl-, Na+, Ca2+, Mg2+ and SO2- 4), as well as the isotopic ratios (2H, 18O, 87Sr/86Sr and 13C) suggest that the salinization occurring in the aquifer water of the coastal plain is related to seawater and the prevailing hydrochemical processes are evaporation, mixing, dissolution and ion exchange. For the unconfined aquifer, groundwater salinization occurred in parts of the area, which is significantly influenced by the land-based sea farming. The integrated impacts of seawater intrusion from the Beibuwan Gulf and infiltration of seawater from the culture ponds is identified in the confined aquifer I at site BBW2. In consequence, the leakage from this polluted aquifer causes the salinization of groundwater in the confined aquifer II. At site BBW3, the confined aquifer I and lower confined aquifer II are remarkably contaminated by seawater intrusion. The weak connectivity with upper aquifers and seaward movement of freshwater prevents saltwater from encroaching the confined aquifer III. Above all, understanding of the origin and processes of groundwater salinization will provide essential information for sustainable planning and management of groundwater resources in this region.

Coastal aquifer management based on surrogate models and multi-objective optimization

Science.gov (United States)

Mantoglou, A.; Kourakos, G.

2011-12-01

The demand for fresh water in coastal areas and islands can be very high, especially in summer months, due to increased local needs and tourism. In order to satisfy demand, a combined management plan is proposed which involves: i) desalinization (if needed) of pumped water to a potable level using reverse osmosis and ii) injection of biologically treated waste water into the aquifer. The management plan is formulated into a multiobjective optimization framework, where simultaneous minimization of economic and environmental costs is desired; subject to a constraint to satisfy demand. The method requires modeling tools, which are able to predict the salinity levels of the aquifer in response to different alternative management scenarios. Variable density models can simulate the interaction between fresh and saltwater; however, they are computationally intractable when integrated in optimization algorithms. In order to alleviate this problem, a multi objective optimization algorithm is developed combining surrogate models based on Modular Neural Networks [MOSA(MNN)]. The surrogate models are trained adaptively during optimization based on a Genetic Algorithm. In the crossover step of the genetic algorithm, each pair of parents generates a pool of offspring. All offspring are evaluated based on the fast surrogate model. Then only the most promising offspring are evaluated based on the exact numerical model. This eliminates errors in Pareto solution due to imprecise predictions of the surrogate model. Three new criteria for selecting the most promising offspring were proposed, which improve the Pareto set and maintain the diversity of the optimum solutions. The method has important advancements compared to previous methods, e.g. alleviation of propagation of errors due to surrogate model approximations. The method is applied to a real coastal aquifer in the island of Santorini which is a very touristy island with high water demands. The results show that the algorithm

Evaluation of the effects of sea-level change and coastal canal management on saltwater intrusion in the Biscayne aquifer of south Florida, USA

Science.gov (United States)

Hughes, J. D.; Sifuentes, D. F.; White, J.

2015-12-01

Sea-level increases are expected to have an effect on the position of the freshwater-saltwater interface in the Biscayne aquifer in south Florida as a result of the low topographic relief of the area and high rates of groundwater withdrawal from the aquifer. To study the effects that future sea-level increases will have on saltwater intrusion in the Biscayne aquifer in Broward County, Florida, a three-dimensional, variable-density, groundwater-flow and transport model was developed. The model was calibrated to observed groundwater heads and chloride concentrations for a 62-year period that includes historic increases in sea level, development of a surface-water management system to control flooding, and increases in groundwater withdrawals as the area transitioned from agricultural to urban land uses. Sensitivity analyses indicate that downward leakage of saltwater from coastal canals and creeks was the primary source of saltwater to the Biscayne aquifer during the last 62-years in areas where the surface-water system is not actively managed and is tidally influenced. In areas removed from the coastal canals and creeks or under active surface-water management, historic groundwater withdrawals were the primary cause of saltwater intrusion into the aquifer. Simulation of future conditions suggests that possible increases in sea level will result in additional saltwater intrusion. Model scenarios suggest that additional saltwater intrusion will be greatest in areas where coastal canals and creeks were historically the primary source of seawater. Future saltwater intrusion in those areas, however, may be reduced by relocation of salinity-control structures.

Studying the impact of climate change on coastal aquifers and adjacent wetlands

Science.gov (United States)

Stigter, Tibor; Ribeiro, Luís.; Oliveira, Rodrigo; Samper, Javier; Fakir, Younes; Fonseca, Luís.; Monteiro, José Paulo; Nunes, João. Pedro; Pisani, Bruno

2010-05-01

program, assessing the impact of climate change on coastal groundwater resources and dependent ecosystems. These resources are often intensively exploited, potentially leading to saltwater intrusion and the degradation of groundwater and dependent wetlands. Climate change may increase this problem in Mediterranean regions, due to the combined effect of rising sea levels and decreasing aquifer recharge. CLIMWAT aims to address this problem by employing a multimethodological approach involving climate scenarios, surface and groundwater flow and transport modeling, as well as hydrochemical indicator and ecological diversity indices. Research is performed in three coastal areas: the Central Algarve in Portugal, the Ebro delta in Spain and the Atlantic Sahel in Morocco. The mean annual temperatures are 17.4 ° C, 17.2 ° C and 17.5 ° C, respectively, whereas mean annual rainfall is lower in the Atlantic Sahel (390 mm) than in the Ebro Delta (520 mm) and the Central Algarve (660 mm). Work package (WP) 1 involves the collection of existing data (in a GIS environment), baseline characterization and the selection of monitoring locations. These include wells and springs of official (water level/quality) monitoring networks, as well as additional observation points selected at strategic locations, including the wetlands receiving groundwater and adjacent aquifer sectors. In WP2 the climate scenarios are selected and integrated in hydrological models (SWAT, GISBALAN), which are developed and calibrated with existing data, prior to scenario modeling. The main focus of this WP is to estimate the evolution of surface runoff and groundwater recharge under climate change. Data on climate change scenarios and model projections are compiled from: (i) the PRUDENCE project; (ii) the ENSEMBLES project; (iii) IPCC scenarios and projections, AR4; (iv) AEMet (Spanish Meteorological Agency) for generation of regional scenarios of climate change in Spain. For Morocco, where runoff is

Combining sound science, legal action and stakeholder involvement to protect a vulnerable coastal aquifer on the island of St. Kitts

Science.gov (United States)

Sahely, H.; Nettles, S.; Burrowes, R.; Haas, G.

2011-12-01

Water resources in small island developing states (SIDS), especially those in the Caribbean are among the most vulnerable systems to human activities and climate change. This vulnerability is exacerbated by a fragmented approach to water resources management. The unconfined coastal aquifer underlying the Basseterre Valley is a significant asset for the people of St. Kitts-Nevis. The potable water extracted from this aquifer represents over 40% of the total water supply for St. Kitts. The area is subject to urban encroachment, inappropriate land use and threats from pollution. A project was implemented using an integrated approach to help government and communities take practical actions to protect this vulnerable aquifer by demonstrating proper management on three fronts: mitigation of threats from contaminants, protection of the aquifer and improved water resources management. The project is funded by the Global Environment Facility (GEF) as part of the Integrating Watershed and Coastal Areas Management (IWCAM) project for Caribbean Small Island States. A comprehensive hydrogeologic evaluation of the aquifer was undertaken in order to aid in the development of a water resources management strategy for the Basseterre Valley Aquifer. Multi-electrode electrical resistivity (MER), a novel surface geophysical technique, was used to delineate the thickness and distribution of sediments throughout the aquifer, zones of increased porosity, zones of possible contamination and the fresh/salt water interface. Together with slowly declining static water levels and elevated dissolved solids levels, the early stages of salt water intrusion have been documented. Groundwater modelling suggests that adjusting the pumping regime, redeveloping some of the existing wells and relocating other wells is a viable option for increasing efficiency and preventing long term dewatering. Overall, the study has provided a wealth of new information about the aquifer for a reasonable cost. A

Arsenic-Safe Aquifers in Coastal Bangladesh: AN Investigation with Ordinary Kriging Estimation

Science.gov (United States)

Hassan, M. M.; Ahamed, R.

2017-10-01

Spatial point pattern is one of the most suitable methods for analysing groundwater arsenic concentrations. Groundwater arsenic poisoning in Bangladesh has been one of the biggest environmental health disasters in recent times. About 85 million people are exposed to arsenic more than 50 μg/L in drinking water. The paper seeks to identify the existing suitable aquifers for arsenic-safe drinking water along with "spatial arsenic discontinuity" using GIS-based spatial geostatistical analysis in a small study site (12.69 km2) in the coastal belt of southwest Bangladesh (Dhopakhali union of Bagerhat district). The relevant spatial data were collected with Geographical Positioning Systems (GPS), arsenic data with field testing kits, tubewell attributes with observation and questionnaire survey. Geostatistics with kriging methods can design water quality monitoring in different aquifers with hydrochemical evaluation by spatial mapping. The paper presents the interpolation of the regional estimates of arsenic data for spatial discontinuity mapping with Ordinary Kriging (OK) method that overcomes the areal bias problem for administrative boundary. This paper also demonstrates the suitability of isopleth maps that is easier to read than choropleth maps. The OK method investigated that around 80 percent of the study site are contaminated following the Bangladesh Drinking Water Standards (BDWS) of 50 μg/L. The study identified a very few scattered "pockets" of arsenic-safe zone at the shallow aquifer.

A New Method to Infer Advancement of Saline Front in Coastal Groundwater Systems by 3D: The Case of Bari (Southern Italy Fractured Aquifer

Directory of Open Access Journals (Sweden)

Costantino Masciopinto

2016-02-01

Full Text Available A new method to study 3D saline front advancement in coastal fractured aquifers has been presented. Field groundwater salinity was measured in boreholes of the Bari (Southern Italy coastal aquifer with depth below water table. Then, the Ghyben-Herzberg freshwater/saltwater (50% sharp interface and saline front position were determined by model simulations of the freshwater flow in groundwater. Afterward, the best-fit procedure between groundwater salinity measurements, at assigned water depth of 1.0 m in boreholes, and distances of each borehole from the modelled freshwater/saltwater saline front was used to convert each position (x, y in groundwater to the water salinity concentration at depth of 1.0 m. Moreover, a second best-fit procedure was applied to the salinity measurements in boreholes with depth z. These results provided a grid file (x, y, z, salinity suitable for plotting the actual Bari aquifer salinity by 3D maps. Subsequently, in order to assess effects of pumping on the saltwater-freshwater transition zone in the coastal aquifer, the Navier-Stokes (N-S equations were applied to study transient density-driven flow and salt mass transport into freshwater of a single fracture. The rate of seawater/freshwater interface advancement given by the N-S solution was used to define the progression of saline front in Bari groundwater, starting from the actual salinity 3D map. The impact of pumping of 335 L·s−1 during the transition period of 112.8 days was easily highlighted on 3D salinity maps of Bari aquifer.

Assessing submarine groundwater discharge (SGD) and nitrate fluxes in highly heterogeneous coastal karst aquifers: Challenges and solutions

Science.gov (United States)

Montiel, Daniel; Dimova, Natasha; Andreo, Bartolomé; Prieto, Jorge; García-Orellana, Jordi; Rodellas, Valentí

2018-02-01

Groundwater discharge in coastal karst aquifers worldwide represents a substantial part of the water budget and is a main pathway for nutrient transport to the sea. Groundwater discharge to the sea manifests under different forms, making its assessment very challenging particularly in highly heterogeneous coastal systems karst systems. In this study, we present a methodology approach to identify and quantify four forms of groundwater discharge in a mixed lithology system in southern Spain (Maro-Cerro Gordo) that includes an ecologically protected coastal area comprised of karstic marble. We found that groundwater discharge to the sea occurs via: (1) groundwater-fed creeks, (2) coastal springs, (3) diffuse groundwater seepage through seabed sediments, and (4) submarine springs. We used a multi-method approach combining tracer techniques (salinity, 224Ra, and 222Rn) and direct measurements (seepage meters and flowmeters) to evaluate the discharge. Groundwater discharge via submarine springs was the most difficult to assess due to their depth (up to 15 m) and extensive development of the springs conduits. We determined that the total groundwater discharge over the 16 km of shoreline of the study area was at least 11 ± 3 × 103 m3 d-1 for the four types of discharge assessed. Groundwater-derived nitrate (NO3-) fluxes to coastal waters over ∼3 km (or 20%) in a highly populated and farmed section of Maro-Cerro Gordo was 641 ± 166 mol d-1, or ∼75% of the total NO3- loading in the study area. We demonstrate in this study that a multi-method approach must be applied to assess all forms of SGD and derived nutrient fluxes to the sea in highly heterogeneous karst aquifer systems.

A General Solution for Groundwater Flow in Estuarine Leaky Aquifer System with Considering Aquifer Anisotropy

Science.gov (United States)

Chen, Po-Chia; Chuang, Mo-Hsiung; Tan, Yih-Chi

2014-05-01

In recent years the urban and industrial developments near the coastal area are rapid and therefore the associated population grows dramatically. More and more water demand for human activities, agriculture irrigation, and aquaculture relies on heavy pumping in coastal area. The decline of groundwater table may result in the problems of seawater intrusion and/or land subsidence. Since the 1950s, numerous studies focused on the effect of tidal fluctuation on the groundwater flow in the coastal area. Many studies concentrated on the developments of one-dimensional (1D) and two-dimensional (2D) analytical solutions describing the tide-induced head fluctuations. For example, Jacob (1950) derived an analytical solution of 1D groundwater flow in a confined aquifer with a boundary condition subject to sinusoidal oscillation. Jiao and Tang (1999) derived a 1D analytical solution of a leaky confined aquifer by considered a constant groundwater head in the overlying unconfined aquifer. Jeng et al. (2002) studied the tidal propagation in a coupled unconfined and confined costal aquifer system. Sun (1997) presented a 2D solution for groundwater response to tidal loading in an estuary. Tang and Jiao (2001) derived a 2D analytical solution in a leaky confined aquifer system near open tidal water. This study aims at developing a general analytical solution describing the head fluctuations in a 2D estuarine aquifer system consisted of an unconfined aquifer, a confined aquifer, and an aquitard between them. Both the confined and unconfined aquifers are considered to be anisotropic. The predicted head fluctuations from this solution will compare with the simulation results from the MODFLOW program. In addition, the solutions mentioned above will be shown to be special cases of the present solution. Some hypothetical cases regarding the head fluctuation in costal aquifers will be made to investigate the dynamic effects of water table fluctuation, hydrogeological conditions, and

Origins and processes of groundwater salinization in the urban coastal aquifers of Recife (Pernambuco, Brazil): A multi-isotope approach

International Nuclear Information System (INIS)

Cary, Lise; Petelet-Giraud, Emmanuelle; Bertrand, Guillaume; Kloppmann, Wolfram; Aquilina, Luc; Martins, Veridiana; Hirata, Ricardo; Montenegro, Suzana; Pauwels, Hélène; Chatton, Eliot; Franzen, Melissa; Aurouet, Axel; Lasseur, Eric; Picot, Géraldine; Guerrot, Catherine; Fléhoc, Christine

2015-01-01

In the coastal multilayer aquifer system of a highly urbanized southern city (Recife, Brazil), where groundwaters are affected by salinization, a multi-isotope approach (Sr, B, O, H) was used to investigate the sources and processes of salinization. The high diversity of the geological bodies, built since the Atlantic opening during the Cretaceous, highly constrains the heterogeneity of the groundwater chemistry, e.g. Sr isotope ratios, and needs to be integrated to explain the salinization processes and groundwater pathways. A paleoseawater intrusion, most probably the 120 ky B.P. Pleistocene marine transgression, and cationic exchange are clearly evidenced in the most salinized parts of the Cabo and Beberibe aquifers. All 87 Sr/ 86 Sr values are above the past and present-day seawater signatures, meaning that the Sr isotopic signature is altered due to additional Sr inputs from dilution with different freshwaters, and water–rock interactions. Only the Cabo aquifer presents a well-delimitated area of Na-HCO 3 water typical of a freshening process. The two deep aquifers also display a broad range of B concentrations and B isotope ratios with values among the highest known to date (63–68.5‰). This suggests multiple sources and processes affecting B behavior, among which mixing with saline water, B sorption on clays and mixing with wastewater. The highly fractionated B isotopic values were explained by infiltration of relatively salty water with B interacting with clays, pointing out the major role played by (palaeo)-channels for the deep Beberibe aquifer recharge. Based on an increase of salinity at the end of the dry season, a present-day seawater intrusion is identified in the surficial Boa Viagem aquifer. Our conceptual model presents a comprehensive understanding of the major groundwater salinization pathways and processes, and should be of benefit for other southern Atlantic coastal aquifers to better address groundwater management issues. - Highlights: �

DNAPL migration in a coastal plain aquifer

International Nuclear Information System (INIS)

DiGuiseppi, W.H.; Jung, A.D.

1995-01-01

Soil and ground water at the Dover Gas Light Superfund Site, a former manufactured gas plant (1859 to 1948), are contaminated with polynuclear aromatic hydrocarbons and volatile organic compounds. Contaminants of concern include light aromatics, such as benzene, toluene, ethylbenzene, and xylenes (BTEX), and heavy aromatics, including naphthalene, acenaphthylene, phenanthrene, and benzo(a)pyrene. Although ground-water contaminant levels are elevated near the site, only naphthalene and acenaphthylene are present within an order of magnitude of their solubility limits, indicating the possibility of dense non-aqueous phase liquids (DNAPL) in the subsurface. The unconfined Columbia Aquifer, which is characterized by interfingering and discontinuous sand, silt, and clay Coastal Plain deposits, overlies a clay aquitard at a depth of 60 feet. The ground water beneath the intermediate clay horizon exhibited little or no contamination, even immediately downgradient from the site. The relationship between the more permeable granular sand horizons and the less permeable interfingering clay zones controls the migration of both the aqueous-phase contamination and the DNAPL. A detailed horizontal and vertical characterization of the subsurface stratigraphy was critical to the accurate interpretation of the extent and magnitude of contamination and the identification and delineation of DNAPL zones

Testing alternative conceptual models of seawater intrusion in a coastal aquifer using computer simulation, southern California, USA

Science.gov (United States)

Nishikawa, Tracy

1997-01-01

Two alternative conceptual models of the physical processes controlling seawater intrusion in a coastal basin in California, USA, were tested to identify a likely principal pathway for seawater intrusion. The conceptual models were tested by using a two-dimensional, finite-element groundwater flow and transport model. This pathway was identified by the conceptual model that best replicated the historical data. The numerical model was applied in cross section to a submarine canyon that is a main avenue for seawater to enter the aquifer system underlying the study area. Both models are characterized by a heterogeneous, layered, water-bearing aquifer. However, the first model is characterized by flat-lying aquifer layers and by a high value of hydraulic conductivity in the basal aquifer layer, which is thought to be a principal conduit for seawater intrusion. The second model is characterized by offshore folding, which was modeled as a very nearshore outcrop, thereby providing a shorter path for seawater to intrude. General conclusions are that: 1) the aquifer system is best modeled as a flat, heterogeneous, layered system; 2) relatively thin basal layers with relatively high values of hydraulic conductivity are the principal pathways for seawater intrusion; and 3) continuous clay layers of low hydraulic conductivity play an important role in controlling the movement of seawater.

Towards a meaningful assessment of marine ecological impacts in life cycle assessment (LCA).

Science.gov (United States)

Woods, John S; Veltman, Karin; Huijbregts, Mark A J; Verones, Francesca; Hertwich, Edgar G

2016-01-01

Human demands on marine resources and space are currently unprecedented and concerns are rising over observed declines in marine biodiversity. A quantitative understanding of the impact of industrial activities on the marine environment is thus essential. Life cycle assessment (LCA) is a widely applied method for quantifying the environmental impact of products and processes. LCA was originally developed to assess the impacts of land-based industries on mainly terrestrial and freshwater ecosystems. As such, impact indicators for major drivers of marine biodiversity loss are currently lacking. We review quantitative approaches for cause-effect assessment of seven major drivers of marine biodiversity loss: climate change, ocean acidification, eutrophication-induced hypoxia, seabed damage, overexploitation of biotic resources, invasive species and marine plastic debris. Our review shows that impact indicators can be developed for all identified drivers, albeit at different levels of coverage of cause-effect pathways and variable levels of uncertainty and spatial coverage. Modeling approaches to predict the spatial distribution and intensity of human-driven interventions in the marine environment are relatively well-established and can be employed to develop spatially-explicit LCA fate factors. Modeling approaches to quantify the effects of these interventions on marine biodiversity are less well-developed. We highlight specific research challenges to facilitate a coherent incorporation of marine biodiversity loss in LCA, thereby making LCA a more comprehensive and robust environmental impact assessment tool. Research challenges of particular importance include i) incorporation of the non-linear behavior of global circulation models (GCMs) within an LCA framework and ii) improving spatial differentiation, especially the representation of coastal regions in GCMs and ocean-carbon cycle models. Copyright © 2016 Elsevier Ltd. All rights reserved.

Numerical simulation of flow in deep open boreholes in a coastal freshwater lens, Pearl Harbor Aquifer, O‘ahu, Hawai‘i

Science.gov (United States)

Rotzoll, Kolja

2012-01-01

The Pearl Harbor aquifer in southern O‘ahu is one of the most important sources of freshwater in Hawai‘i. A thick freshwater lens overlays brackish and saltwater in this coastal aquifer. Salinity profiles collected from uncased deep monitor wells (DMWs) commonly are used to monitor freshwater-lens thickness. However, vertical flow in DMWs can cause the measured salinity to differ from salinity in the adjacent aquifer or in an aquifer without a DWM. Substantial borehole flow and displacement of salinity in DMWs over several hundred feet have been observed in the Pearl Harbor aquifer. The objective of this study was to evaluate the effects of borehole flow on measured salinity profiles from DMWs. A numerical modeling approach incorporated aquifer hydraulic characteristics and recharge and withdrawal rates representative of the Pearl Harbor aquifer. Borehole flow caused by vertical hydraulic gradients associated with both the natural regional flow system and groundwater withdrawals was simulated. Model results indicate that, with all other factors being equal, greater withdrawal rates, closer withdrawal locations, or higher hydraulic conductivities of the well cause greater borehole flow and displacement of salinity in the well. Borehole flow caused by the natural groundwater-flow system is five orders of magnitude greater than vertical flow in a homogeneous aquifer, and borehole-flow directions are consistent with the regional flow system: downward flow in inland recharge areas and upward flow in coastal discharge areas. Displacement of salinity inside the DMWs associated with the regional groundwater-flow system ranges from less than 1 to 220 ft, depending on the location and assumed hydraulic conductivity of the well. For example, upward displacements of the 2 percent and 50 percent salinity depths in a well in the coastal discharge part of the flow system are 17 and 4.4 ft, respectively, and the average salinity difference between aquifer and borehole is 0

Development of a sharp interface model that simulates coastal aquifer flow with the coupled use of GIS

Science.gov (United States)

Gemitzi, Alexandra; Tolikas, Demetrios

A simulation program, which works seamlessly with GIS and simulates flows in coastal aquifers, is presented in the present paper. The model is based on the Galerkin finite element discretization scheme and it simulates both steady and transient freshwater and saltwater flow, assuming that the two fluids are separated by a sharp interface. The model has been verified in simple cases where analytical solutions exist. The simulation program works as a tool of the GIS program, which is the main database that stores and manages all the necessary data. The combined use of the simulation and the GIS program forms an integrated management tool offering a simpler way of simulating and studying saline intrusion in coastal aquifers. Application of the model to the Yermasogia aquifer illustrates the coupled use of modeling and GIS techniques for the examination of regional coastal aquifer systems. Pour étudier un système aquifère côtier, nous avons développé un modèle aux éléments finis en quasi 3-D qui simule les écoulements d'eau douce et d'eau salée en régime aussi bien permanent que transitoire. Les équations qui les régissent sont discrétisées par un schéma de discrétisation de Garlekin aux éléments finis. Le modèle a été vérifié dans des cas simples où il existe des solutions analytiques. Toutes les données nécessaires sont introduites et gérées grâce à un logiciel de gestion de SIG. Le programme de simulation est utilisé comme un outil du logiciel de SIG, constituant ainsi un outil de gestion intégrée dont le but est de simuler et d'étudier l'intrusion saline dans les aquifères côtiers. L'application du modèle à l'aquifère de Yermasogia illustre l'utilisation couplée de la modélisation et des techniques de SIG pour l'étude des systèmes aquifères côtiers régionaux. Se ha desarrollado un modelo casi tridimensional de elementos finitos para simular el flujo de agua dulce y salada, tanto en régimen estacionario como en

LCA Experiences in Danish Industry

DEFF Research Database (Denmark)

Broberg, Ole; Christensen, Per

1999-01-01

of the products with subsequent new priorities in the environmental efforts. Only a few enterprises have built up in-house LCA competence whereas consultants are heavily involved in LCA work. In large enterprises LCA work is pre-dominantly carried out by environmental staff members, but also product development...

Life cycle assessment (LCA)

DEFF Research Database (Denmark)

Thrane, Mikkel; Schmidt, Jannick Andresen

2004-01-01

The chapter introduces Life Cycle Assessment (LCA) and its application according to the ISO 1404043 standards.......The chapter introduces Life Cycle Assessment (LCA) and its application according to the ISO 1404043 standards....

Origins and processes of groundwater salinization in the urban coastal aquifers of Recife (Pernambuco, Brazil): A multi-isotope approach

Energy Technology Data Exchange (ETDEWEB)

Cary, Lise, E-mail: l.cary@brgm.fr [BRGM French Geological Survey, 3 Avenue Claude Guillemin, 45060 Orléans Cedex 2 (France); Petelet-Giraud, Emmanuelle [BRGM French Geological Survey, 3 Avenue Claude Guillemin, 45060 Orléans Cedex 2 (France); Bertrand, Guillaume [Institute of Geosciences, University of São Paulo, Rua do Lago, 562 Butantã, 05508-080 Sao Paulo (Brazil); Kloppmann, Wolfram [BRGM French Geological Survey, 3 Avenue Claude Guillemin, 45060 Orléans Cedex 2 (France); Aquilina, Luc [OSUR-Géosciences Rennes, Université Rennes 1 — CNRS, 35000 Rennes (France); Martins, Veridiana; Hirata, Ricardo [Institute of Geosciences, University of São Paulo, Rua do Lago, 562 Butantã, 05508-080 Sao Paulo (Brazil); Montenegro, Suzana [Civil Engineering Department, Federal University of Pernambuco, 50740 Recife, PE Brazil (Brazil); Pauwels, Hélène [BRGM French Geological Survey, 3 Avenue Claude Guillemin, 45060 Orléans Cedex 2 (France); Chatton, Eliot [OSUR-Géosciences Rennes, Université Rennes 1 — CNRS, 35000 Rennes (France); Franzen, Melissa [CPRM, Brazilian Geologic Survey, Avenida Sul 2291, Recife PE (Brazil); Aurouet, Axel [Géo-Hyd, 101 rue Jacques Charles, 45160 Olivet (France); Lasseur, Eric; Picot, Géraldine; Guerrot, Catherine; Fléhoc, Christine [BRGM French Geological Survey, 3 Avenue Claude Guillemin, 45060 Orléans Cedex 2 (France); and others

2015-10-15

In the coastal multilayer aquifer system of a highly urbanized southern city (Recife, Brazil), where groundwaters are affected by salinization, a multi-isotope approach (Sr, B, O, H) was used to investigate the sources and processes of salinization. The high diversity of the geological bodies, built since the Atlantic opening during the Cretaceous, highly constrains the heterogeneity of the groundwater chemistry, e.g. Sr isotope ratios, and needs to be integrated to explain the salinization processes and groundwater pathways. A paleoseawater intrusion, most probably the 120 ky B.P. Pleistocene marine transgression, and cationic exchange are clearly evidenced in the most salinized parts of the Cabo and Beberibe aquifers. All {sup 87}Sr/{sup 86}Sr values are above the past and present-day seawater signatures, meaning that the Sr isotopic signature is altered due to additional Sr inputs from dilution with different freshwaters, and water–rock interactions. Only the Cabo aquifer presents a well-delimitated area of Na-HCO{sub 3} water typical of a freshening process. The two deep aquifers also display a broad range of B concentrations and B isotope ratios with values among the highest known to date (63–68.5‰). This suggests multiple sources and processes affecting B behavior, among which mixing with saline water, B sorption on clays and mixing with wastewater. The highly fractionated B isotopic values were explained by infiltration of relatively salty water with B interacting with clays, pointing out the major role played by (palaeo)-channels for the deep Beberibe aquifer recharge. Based on an increase of salinity at the end of the dry season, a present-day seawater intrusion is identified in the surficial Boa Viagem aquifer. Our conceptual model presents a comprehensive understanding of the major groundwater salinization pathways and processes, and should be of benefit for other southern Atlantic coastal aquifers to better address groundwater management issues

Cradle to Cradle and LCA

DEFF Research Database (Denmark)

Bjørn, Anders; Hauschild, Michael Z.

2018-01-01

with the circular economy , the C2C certification and examples of C2C certified or inspired products and systems. This is followed by a comparison of C2C with eco-efficiency and LCA . Because of their important differences, we conclude that care should be taken when combing C2C and LCA, e.g. using LCA to evaluate......Cradle to Cradle (C2C) offers a positive vision of a future, where products are radically redesigned to be beneficial to humans and the environment. The idea is not to reduce negative impacts (as in LCA), but to increase positive impacts . This chapter presents the C2C concept and its relationship...... products inspired by C2C. We then provide an in-depth analysis of the conflicts between C2C and LCA and offer solutions. Finally, we reflect upon how LCA practitioners can learn from C2C in terms of providing a vision of a sustainable future, creating a sense of urgency for change and communicating results...

Modelling the effects of tides and storm surges on coastal aquifers using a coupled surface-subsurface approach.

Science.gov (United States)

Yang, Jie; Graf, Thomas; Herold, Maria; Ptak, Thomas

2013-06-01

Coastal aquifers are complex hydrologic systems because many physical processes interact: (i) variably saturated flow, (ii) spatial-temporal fluid density variations, (iii) tidal fluctuations, (iv) storm surges overtopping dykes, and (v) surface runoff of storm water. The HydroGeoSphere model is used to numerically simulate coastal flow dynamics, assuming a fully coupled surface-subsurface approach, accounting for all processes listed above. The diffusive wave approximation of the St. Venant equation is used to describe surface flow. Surface flow and salt transport are fully coupled with subsurficial variably saturated, variable-density flow and salt transport through mathematical terms that represent exchange of fluid mass and solute mass, respectively. Tides and storm surges induce a time-variant head that is applied to nodes of the surface domain. The approach is applied to real cases of tide and storm surge events. Tide simulation results confirm the existence of a recirculating zone, forming beneath the upper part of the intertidal zone. By monitoring the exchange fluid flux rates through the beach, it was found that the major inflow to the aquifer takes place at the upper part of the intertidal zone, which explains the formation of the recirculating zone. The recirculating zone is forming particularly during rising tide. Results from a storm surge simulation show that plume fingers develop below the flooded land surface. Natural remediation by seaward flowing freshwater is relatively slow, such that reducing the salt concentration in the aquifer down to drinking water standards takes up to 10 years. Copyright © 2013 Elsevier B.V. All rights reserved.

A correction on coastal heads for groundwater flow models.

Science.gov (United States)

Lu, Chunhui; Werner, Adrian D; Simmons, Craig T; Luo, Jian

2015-01-01

We introduce a simple correction to coastal heads for constant-density groundwater flow models that contain a coastal boundary, based on previous analytical solutions for interface flow. The results demonstrate that accurate discharge to the sea in confined aquifers can be obtained by direct application of Darcy's law (for constant-density flow) if the coastal heads are corrected to ((α + 1)/α)hs  - B/2α, in which hs is the mean sea level above the aquifer base, B is the aquifer thickness, and α is the density factor. For unconfined aquifers, the coastal head should be assigned the value hs1+α/α. The accuracy of using these corrections is demonstrated by consistency between constant-density Darcy's solution and variable-density flow numerical simulations. The errors introduced by adopting two previous approaches (i.e., no correction and using the equivalent fresh water head at the middle position of the aquifer to represent the hydraulic head at the coastal boundary) are evaluated. Sensitivity analysis shows that errors in discharge to the sea could be larger than 100% for typical coastal aquifer parameter ranges. The location of observation wells relative to the toe is a key factor controlling the estimation error, as it determines the relative aquifer length of constant-density flow relative to variable-density flow. The coastal head correction method introduced in this study facilitates the rapid and accurate estimation of the fresh water flux from a given hydraulic head measurement and allows for an improved representation of the coastal boundary condition in regional constant-density groundwater flow models. © 2014, National Ground Water Association.

EPA Region 1 Sole Source Aquifers

Science.gov (United States)

This coverage contains boundaries of EPA-approved sole source aquifers. Sole source aquifers are defined as an aquifer designated as the sole or principal source of drinking water for a given aquifer service area; that is, an aquifer which is needed to supply 50% or more of the drinking water for the area and for which there are no reasonable alternative sources should the aquifer become contaminated.The aquifers were defined by a EPA hydrogeologist. Aquifer boundaries were then drafted by EPA onto 1:24000 USGS quadrangles. For the coastal sole source aquifers the shoreline as it appeared on the quadrangle was used as a boundary. Delineated boundaries were then digitized into ARC/INFO.

Characterizations of pumping-induced land subsidence in coastal aquifers - model development and field-scale implementations

Science.gov (United States)

Ni, C.; Huang, Y.; Lu, C.

2012-12-01

The pumping-induced land subsidence events are typically founded in coastal aquifers in Taiwan especially in the areas of lower alluvial fans. Previous investigations have recognized the irreversible situation for an aquifer deformation even if the pumped water is significantly reduced or stopped. Long-term monitoring projects on land subsidence in Choshui alluvial fan in central Taiwan have improved the understanding of the deformations in the aquifer system. To characterization the detailed land subsidence mechanism, this study develops an inverse numerical model to estimate the deformation parameters such as the specific storage (Ss) and vertical hydraulic conductivity (Kv) for interbeds. Similar to the concept of Hydraulic tomography survey (HTS), the developed model employs the iterative cokriging estimator to improve the accuracy of estimating deformation parameters. A one-dimensional numerical example is employed to assess the accuracy of the developed inverse model. The developed model is then applied to field-scale data from compaction monitoring wells (CMW) installed in the lower Choshui River fan. Results of the synthetic example show that the developed inverse model can reproduce well the predefined geologic features of the synthetic aquifer. The model provides better estimations of Kv patterns and magnitudes. Slightly less detail of the Ss was obtained due to the insensitivity of transient stresses for specified sampling times. Without prior information from field measurements, the developed model associated with deformation measurements form CMW can estimate Kv and Ss fields with great spatial resolution.

Intensively exploited Mediterranean aquifers: resilience and proximity to critical points of seawater intrusion

Science.gov (United States)

Mazi, K.; Koussis, A. D.; Destouni, G.

2013-11-01

We investigate here seawater intrusion in three prominent Mediterranean aquifers that are subject to intensive exploitation and modified hydrologic regimes by human activities: the Nile Delta Aquifer, the Israel Coastal Aquifer and the Cyprus Akrotiri Aquifer. Using a generalized analytical sharp-interface model, we review the salinization history and current status of these aquifers, and quantify their resilience/vulnerability to current and future sea intrusion forcings. We identify two different critical limits of sea intrusion under groundwater exploitation and/or climatic stress: a limit of well intrusion, at which intruded seawater reaches key locations of groundwater pumping, and a tipping point of complete sea intrusion upto the prevailing groundwater divide of a coastal aquifer. Either limit can be reached, and ultimately crossed, under intensive aquifer exploitation and/or climate-driven change. We show that sea intrusion vulnerability for different aquifer cases can be directly compared in terms of normalized intrusion performance curves. The site-specific assessments show that the advance of seawater currently seriously threatens the Nile Delta Aquifer and the Israel Coastal Aquifer. The Cyprus Akrotiri Aquifer is currently somewhat less threatened by increased seawater intrusion.

The influence of fish ponds and salinization on groundwater quality in the multi-layer coastal aquifer system in Israel

Science.gov (United States)

Tal, A.; Weinstein, Y.; Yechieli, Y.; Borisover, M.

2017-08-01

This study focuses on the impact of surface reservoirs (fish ponds) on a multi aquifer coastal system, and the relation between the aquifer and the sea. The study was conducted in an Israeli Mediterranean coastal aquifer, which includes a sandy phreatic unit and two confined calcareous sandstone units. The geological description is based on 52 wells, from which 33 samples were collected for stable isotope analysis and 25 samples for organic and inorganic parameters. Hydraulic head and chemical measurements suggest that there is an hydraulic connection between the fish ponds above the aquifer and the phreatic unit, whereas the connection with the confined units is very limited. The phreatic unit is characterized by a low concentration of oxygen and high concentrations of ammonium and phosphate, while the confined units are characterized by higher oxygen and much lower ammonium and phosphate concentrations. Organic matter fluorescence was found to be a tool to distinguish the contribution of the pond waters, whereby a pond water signature (characterized by proteinaceous (tryptophan-like) and typical humic-matter fluorescence) was found in the phreatic aquifer. The phreatic unit is also isotopically enriched, similar to pond waters, with δ18O of -1‰ and δD of -4.6‰, indicating enhanced evaporation of the pond water before infiltration, whereas there is a depleted isotopic composition in the confined units (δ18O = -4.3‰, δD = -20.4‰), which are also OM-poor. The Phreeqc model was used for quantitative calculation of the effect of pond losses on the different units. The Dissolved Inorganic Nitrogen (DIN) in the upper unit increases downstream from the ponds toward the sea, probably due to organic matter degradation, suggesting contribution of DIN from shallow groundwater flow to the sea. 87Sr/86Sr and Mg/Ca in the brackish and saline groundwater of the lower confined units increase toward seawater value, suggesting that the salinization process in the region

Evaluation of environmental impact by LCA method. LCA shuho ni yoru kankyo fuka hyoka

Energy Technology Data Exchange (ETDEWEB)

Sakamura, H.; Utsuno, F.; Yasui, I. (The University of Tokyo, Tokyo (Japan). Institute of Industrial Science)

1994-06-01

This paper explains the concept, history, and analytic methods of life cycle assessment (LCA), showing its application to beer bottles and cement factories as specific examples. The LCA is a method to calculate substances and energies put into the whole process of production of a product from raw material mining to product wasting and environmental loads emitted therefrom. It also evaluates the result collectively and quantitatively. A first case of the research is reportedly the one performed at Coca-Cola Co., Ltd. in 1969. Full-scale researches have gone forward in European countries in the recent several years, and are progressing to international networks. The analytic methods can be divided largely into an accumulation method to analyze data in each process and add them up, and a method to use an industrial association table. The former method is the most generally used method currently in overseas countries if referred to the LCA. Because the LCA can cause the analytic result and evaluation to vary depending on the purpose, it is important to define the goal, and set the scope. The LCA must develop in the future although it has a number of problems. 10 refs., 5 figs., 2 tabs.

Nonstationary porosity evolution in mixing zone in coastal carbonate aquifer using an alternative modeling approach.

Science.gov (United States)

Laabidi, Ezzeddine; Bouhlila, Rachida

2015-07-01

In the last few decades, hydrogeochemical problems have benefited from the strong interest in numerical modeling. One of the most recognized hydrogeochemical problems is the dissolution of the calcite in the mixing zone below limestone coastal aquifer. In many works, this problem has been modeled using a coupling algorithm between a density-dependent flow model and a geochemical model. A related difficulty is that, because of the high nonlinearity of the coupled set of equations, high computational effort is needed. During calcite dissolution, an increase in permeability can be identified, which can induce an increase in the penetration of the seawater into the aquifer. The majority of the previous studies used a fully coupled reactive transport model in order to model such problem. Romanov and Dreybrodt (J Hydrol 329:661-673, 2006) have used an alternative approach to quantify the porosity evolution in mixing zone below coastal carbonate aquifer at steady state. This approach is based on the analytic solution presented by Phillips (1991) in his book Flow and Reactions in Permeable Rock, which shows that it is possible to decouple the complex set of equation. This equation is proportional to the square of the salinity gradient, which can be calculated using a density driven flow code and to the reaction rate that can be calculated using a geochemical code. In this work, this equation is used in nonstationary step-by-step regime. At each time step, the quantity of the dissolved calcite is quantified, the change of porosity is calculated, and the permeability is updated. The reaction rate, which is the second derivate of the calcium equilibrium concentration in the equation, is calculated using the PHREEQC code (Parkhurst and Apello 1999). This result is used in GEODENS (Bouhlila 1999; Bouhlila and Laabidi 2008) to calculate change of the porosity after calculating the salinity gradient. For the next time step, the same protocol is used but using the updated porosity

Intensively exploited Mediterranean aquifers: resilience to seawater intrusion and proximity to critical thresholds

Science.gov (United States)

Mazi, K.; Koussis, A. D.; Destouni, G.

2014-05-01

We investigate seawater intrusion in three prominent Mediterranean aquifers that are subject to intensive exploitation and modified hydrologic regimes by human activities: the Nile Delta, Israel Coastal and Cyprus Akrotiri aquifers. Using a generalized analytical sharp interface model, we review the salinization history and current status of these aquifers, and quantify their resilience/vulnerability to current and future seawater intrusion forcings. We identify two different critical limits of seawater intrusion under groundwater exploitation and/or climatic stress: a limit of well intrusion, at which intruded seawater reaches key locations of groundwater pumping, and a tipping point of complete seawater intrusion up to the prevailing groundwater divide of a coastal aquifer. Either limit can be reached, and ultimately crossed, under intensive aquifer exploitation and/or climate-driven change. We show that seawater intrusion vulnerability for different aquifer cases can be directly compared in terms of normalized intrusion performance curves. The site-specific assessments show that (a) the intruding seawater currently seriously threatens the Nile Delta aquifer, (b) in the Israel Coastal aquifer the sharp interface toe approaches the well location and (c) the Cyprus Akrotiri aquifer is currently somewhat less threatened by increased seawater intrusion.

Seawater intrusion in the gravelly confined aquifer of the coastal Pisan Plain (Tuscany): hydrogeological and geochemical investigation to assess causes and consequences

Science.gov (United States)

Doveri, M.; Giannecchini, R.; Butteri, M.

2012-12-01

The gravelly horizon of the Pisa plain multilayered system is a confined aquifer tapped by a large number of wells. It hosts a very important water resource for drinking, industrial and irrigable uses, but may be affected by seawater intrusion coming from the coastal area; most wells is distributed inland, anyway a significant exploitation along the coastal area is also present to supply farms and tourist services. Previous hydrogeological and geochemical investigations carried out in coastal area stated maximum percentage of seawater in gravelly aquifer of about 7-9% and suggested the presence of two different mechanisms (Doveri et alii, 2010): i) a direct seawater intrusion from the zone where the gravelly aquifer is in contact with the sea floor; ii) a mixing process between freshwater and seawater, the latter deriving from the Arno river-shallow sandy aquifer system. Basing on these results, since January 2012 a new two-year project was financed by the MSRM Regional Park. Major aims are a better definition of such phenomena and their distribution on the territory, and an assessing of the seawater intrusion trend in relation to groundwater exploitation. Eleven piezometers were realised during first semester of 2012, thus improving the measurement network, which is now made up by 40 wells/piezometers distributed on about 60 km^2. Comparing new and previous borehole data a general confinement of the gravelly aquifer is confirmed, excepting in the northern part where the aquifer is in contact with the superficial sandy one. Preliminary field measurement was performed in June 2012, during which water level (WL) and electrical conductivity (EC) data were collected. WLs below the sea-level were observed on most of the studied area, with a minimum value of about -5 m a.s.l. in the inner part of the northern zone, where major exploitation is present. Moreover, a relative minimum of WL (about -2 m a.s.l.) is present near the shoreline in the southern zone. In the latter

Challenges in groundwater resource management in coastal aquifers of East Africa: Investigations and lessons learnt in the Comoros Islands, Kenya and Tanzania

Directory of Open Access Journals (Sweden)

Jean-Christophe Comte

2016-03-01

Full Text Available Study region: Coastal areas of Kenya (Kilifi County, Tanzania (Kilwa district and Comoros (Ngazidja island, East Africa. Study focus: Research aimed to understand the physical and societal drivers of groundwater accessibility and identify critical aspects of groundwater access and knowledge gaps that require further monitoring and research. Interdisciplinary societal, environmental and hydrogeological investigations were consistently undertaken in the three areas considered as exemplars of the diversity of the coastal fringes of the wider region. This paper focuses on the hydrogeological outcomes of the research, framed within the principal socio-environmental issues identified. New hydrological insights: Results confirm the fundamental importance of coastal groundwater resources for the development of the region and the urgent need to match groundwater development with demographic and economic growth. Hydrogeological knowledge is fragmented, groundwater lacks a long-term monitoring infrastructure and information transfer from stakeholders to users is limited. Current trends in demography, climate, sea-level and land-use are further threatening freshwater availability. Despite possessing high-productivity aquifers, water quality from wells and boreholes is generally impacted by saltwater intrusion. Shallow large-diameter wells, following the traditional model of these areas, consistently prove to be less saline and more durable than deeper small-diameter boreholes. However, promoting the use of large numbers of shallow wells poses a significant challenge for governance, requiring coherent management of the resource at local and national scales and the engagement of local communities. Keywords: Groundwater, Coastal aquifer, Eastern Africa, Environmental change, Governance, Community engagement

Geochemical characterization and heavy metal migration in a coastal polluted aquifer incorporating tidal effects: field investigation in Chongming Island, China.

Science.gov (United States)

Liu, Shuguang; Tan, Bo; Dai, Chaomeng; Lou, Sha; Tao, An; Zhong, Guihui

2015-12-01

The occurrence and migration of heavy metal in coastal aquifer incorporating tidal effects were investigated in detail by the field geological survey and observation. The continuous groundwater sampling, field observation (for groundwater potentiometric surface elevation, pH, dissolved oxygen, temperature, and salinity), and laboratory analysis (for Cr, Ni, Cu, Zn, Cd, and Pb concentration) were conducted through eight monitoring wells located around the landfill in the northern part of Chongming Island, China. The results showed that the unconfined aquifer medium was estuary-littoral facies deposit of Holocene, mainly gray clayey silt and grey sandy silt, and the groundwater flow was mainly controlled by topography condition of the aquifer formation strike. The background values of Cr, Ni, Cu, Zn, Cd, and Pb in Chongming Island were 3.10 ± 3.09, 0.81 ± 0.25, 1.48 ± 1.09, 43.32 ± 33.06, 0.08 ± 0.16, and 0.88 ± 1.74 μg/L, respectively. Compared with the groundwater samples around the study area, the drinking water was qualified and was free from the seawater intrusion/estuarine facies contaminant encroachment. Pollutant discharge was reflected in water quality parameters, the Cr and Cu concentrations elevated to the peak of 50.07 and 46.00 μg/L, respectively, and meanwhile specific migration regularity was embodied in observation time series as well as other elements. This migration regularity was not fully identical according to correlations between these analyzed elements. Ambient watery environment, anthropogenic disturbance, regional hydrogeological condition, and biogeochemical reactivity on heavy metals reduced/altered the significance of elements correlation in the migration pathway in coastal aquifer.

Identification of the mechanisms and origin of salinization of groundwaters in coastal aquifers by means of isotopic techniques

International Nuclear Information System (INIS)

Araguas, L. J.; Quejido, A. J.

2007-01-01

To study the origin of salinity and the mechanisms operating in coastal aquifers, a set of tools is available to determine the essential aspects of the hydrogeological behaviour of the system. these tools are based on the integrated use of hydrochemical parameters (major constituents and trace elements) and isotopic parameters (oxygen, hydrogen, sulfur, carbon, strontium and boron). In addition to the active intrusion of seawater, salinization in coastal areas may be influenced by various human activities that accelerate the degradation of water quality, such as concentrated pumping, intensive farming techniques with return of irrigation water, or reuse of urban and industrial waste water. Characterization of the dominant processes and mechanisms is required for suitable management of the resource and implementation of corrective measures. (Author)

Hydrogeology and Aquifer Storage and Recovery Performance in the Upper Floridan Aquifer, Southern Florida

Science.gov (United States)

Reese, Ronald S.; Alvarez-Zarikian, Carlos A.

2007-01-01

Well construction, hydraulic well test, ambient water-quality, and cycle test data were inventoried and compiled for 30 aquifer storage and recovery facilities constructed in the Floridan aquifer system in southern Florida. Most of the facilities are operated by local municipalities or counties in coastal areas, but five sites are currently being evaluated as part of the Comprehensive Everglades Restoration Plan. The relative performance of all sites with adequate cycle test data was determined, and compared with four hydrogeologic and design factors that may affect recovery efficiency. Testing or operational cycles include recharge, storage, and recovery periods that each last days or months. Cycle test data calculations were made including the potable water (chloride concentration of less than 250 milligrams per liter) recovery efficiency per cycle, total recovery efficiency per cycle, and cumulative potable water recovery efficiencies for all of the cycles at each site. The potable water recovery efficiency is the percentage of the total amount of potable water recharged for each cycle that is recovered; potable water recovery efficiency calculations (per cycle and cumulative) were the primary measures used to evaluate site performance in this study. Total recovery efficiency, which is the percent recovery at the end of each cycle, however, can be substantially higher and is the performance measure normally used in the operation of water-treatment plants. The Upper Floridan aquifer of the Floridan aquifer system currently is being used, or planned for use, at 29 of the aquifer storage and recovery sites. The Upper Floridan aquifer is continuous throughout southern Florida, and its overlying confinement is generally good; however, the aquifer contains brackish to saline ground water that can greatly affect freshwater storage and recovery due to dispersive mixing within the aquifer. The hydrogeology of the Upper Floridan varies in southern Florida; confinement

HYDROGEOLOGY AND CONCEPTUAL MODEL OF THE KARSTIC COASTAL AQUIFER IN NORTHERN YUCATAN STATE, MEXICO

Directory of Open Access Journals (Sweden)

Miguel J Villasuso-Pino

2011-04-01

Full Text Available The coastal zone of northern Yucatan Peninsula (YP is mainly constituted by Tertiary limestones, covered by Pleistocen limestones, where there exist swamps and estuary systems, locally called “rías”, with mouths connecting them to the sea and hence being a way for an important amount of groundwater to discharge, like in Ría Lagartos and Celestún. These limestones have karstic layers located at depths from 8 to 16 meters below terrain surface.  It is in these layers where groundwater mainly flows toward coast, passing below the sand dune and discharging in the sea in the form of submarine springs which in many cases manifest themselves on the marine surface depending on the hydraulic or piezometric fresh water head. The width of the superficial limestone within this coastal fringe, called “caliche”, varies from 5 to 10 kilometers in the study zone (Chuburna-Progreso-Chicxulub.  Its permeability is extremely low, so it constitutes a confining layer that impedes superficial waters to percolate toward groundwater.  The hydraulic head of the groundwater below this confining layer is over the mean sea level and also over the swamp water level, coastal lagoons and estuaries. There are two important hydrological phenomena that occur in this coastal fringe: 1 There is no recharge to the aquifer (groundwater due to limestone rock outcrops is impermeable or semipermeable; and 2 groundwater pressure is not lost, nor saline interfase is rised if the superficial layer is broken.  The groundwater pollution vulnerability within this coastal fringe is less than that for the superficial saline waters of swamps and estuaries, because of caliche’s low intrinsic permeability that impedes percolation.

USEEIOv1.1 - openLCA

Data.gov (United States)

U.S. Environmental Protection Agency — This is a version of the full USEEIO v1.1 model in the openLCA schema serialized as JSON-LD that can be imported into openLCA software (www.openlca.org) v1.5 and...

Attributional and consequential LCA of milk production

NARCIS (Netherlands)

Thomassen, M.A.; Dalgaard, P.; Heijungs, R.; Boer, de I.J.M.

2008-01-01

Background, aim and scope Different ways of performing a life cycle assessment (LCA) are used to assess the environmental burden of milk production. A strong connection exists between the choice between attributional LCA (ALCA) and consequential LCA (CLCA) and the choice of how to handle

Attributional and consequential LCA of milk production

NARCIS (Netherlands)

Thomassen, Marlies A.; Dalgaard, Randi; Heijungs, Reinout; De Boer, Imke

Background, aim and scope: Different ways of performing a life cycle assessment (LCA) are used to assess the environmental burden of milk production. A strong connection exists between the choice between attributional LCA (ALCA) and consequential LCA (CLCA) and the choice of how to handle

Use of Input–Output Analysis in LCA

DEFF Research Database (Denmark)

Mattila, Tuomas J.

2018-01-01

Input–output analysis can be used as a tool for complementing the traditionally process-based life cycle assessment (LCA) with macroeconomic data from the background systems. Properly used, it can result in faster and more accurate LCA. It also provides opportunities for streamlining the LCA inve...

Quality of Shallow Groundwater and Drinking Water in the Mississippi Embayment-Texas Coastal Uplands Aquifer System and the Mississippi River Valley Alluvial Aquifer, South-Central United States, 1994-2004

Science.gov (United States)

Welch, Heather L.; Kingsbury, James A.; Tollett, Roland W.; Seanor, Ronald C.

2009-01-01

The Mississippi embayment-Texas coastal uplands aquifer system is an important source of drinking water, providing about 724 million gallons per day to about 8.9 million people in Texas, Louisiana, Mississippi, Arkansas, Missouri, Tennessee, Kentucky, Illinois, and Alabama. The Mississippi River Valley alluvial aquifer ranks third in the Nation for total withdrawals of which more than 98 percent is used for irrigation. From 1994 through 2004, water-quality samples were collected from 169 domestic, monitoring, irrigation, and public-supply wells in the Mississippi embayment-Texas coastal uplands aquifer system and the Mississippi River Valley alluvial aquifer in various land-use settings and of varying well capacities as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Groundwater samples were analyzed for physical properties and about 200 water-quality constituents, including total dissolved solids, major inorganic ions, trace elements, radon, nutrients, dissolved organic carbon, pesticides, pesticide degradates, and volatile organic compounds. The occurrence of nutrients and pesticides differed among four groups of the 114 shallow wells (less than or equal to 200 feet deep) in the study area. Tritium concentrations in samples from the Holocene alluvium, Pleistocene valley trains, and shallow Tertiary wells indicated a smaller component of recent groundwater than samples from the Pleistocene terrace deposits. Although the amount of agricultural land overlying the Mississippi River Valley alluvial aquifer was considerably greater than areas overlying parts of the shallow Tertiary and Pleistocene terrace deposits wells, nitrate was rarely detected and the number of pesticides detected was lower than other shallow wells. Nearly all samples from the Holocene alluvium and Pleistocene valley trains were anoxic, and the reducing conditions in these aquifers likely result in denitrification of nitrate. In contrast, most samples from the

Coastal groundwater salinization: Focus on the vertical variability in a multi-layered aquifer through a multi-isotope fingerprinting (Roussillon Basin, France)

Energy Technology Data Exchange (ETDEWEB)

Petelet-Giraud, Emmanuelle, E-mail: e.petelet@brgm.fr [BRGM, Avenue C. Guillemin, BP 36009, 45060 Orléans Cedex 02 (France); Négrel, Philippe [BRGM, Avenue C. Guillemin, BP 36009, 45060 Orléans Cedex 02 (France); Aunay, Bertrand [BRGM, Réunion Agency, 5, rue Sainte-Anne, CS 51016, 97404 Saint Denis Cedex (France); Ladouche, Bernard; Bailly-Comte, Vincent [BRGM Montpellier Agency, 1039, rue de Pinville, 34000 Montpellier (France); Guerrot, Catherine; Flehoc, Christine [BRGM, Avenue C. Guillemin, BP 36009, 45060 Orléans Cedex 02 (France); Pezard, Philippe; Lofi, Johanna [Géosciences Montpellier, UMR 5243, Université de Montpellier, cc069, Place Eugène Bataillon, 34095 Montpellier Cedex 05 (France); Dörfliger, Nathalie [BRGM, Avenue C. Guillemin, BP 36009, 45060 Orléans Cedex 02 (France)

2016-10-01

The Roussillon sedimentary Basin (South France) is a complex multi-layered aquifer, close to the Mediterranean Sea facing seasonally increases of water abstraction and salinization issues. We report geochemical and isotopic vertical variability in this aquifer using groundwater sampled with a Westbay System® at two coastal monitoring sites: Barcarès and Canet. The Westbay sampling allows pointing out and explaining the variation of water quality along vertical profiles, both in productive layers and in the less permeable ones where most of the chemical processes are susceptible to take place. The aquifer layers are not equally impacted by salinization, with electrical conductivity ranging from 460 to 43,000 μS·cm{sup −1}. The δ{sup 2}H–δ{sup 18}O signatures show mixing between seawater and freshwater components with long water residence time as evidenced by the lack of contribution from modern water using {sup 3}H, {sup 14}C and CFCs/SF6. S(SO{sub 4}) isotopes also evidence seawater contribution but some signatures can be related to oxidation of pyrite and/or organically bounded S. In the upper layers {sup 87}Sr/{sup 86}Sr ratios are close to that of seawater and then increase with depth, reflecting water–rock interaction with argillaceous formations while punctual low values reflect interaction with carbonate. Boron isotopes highlight secondary processes such as adsorption/desorption onto clays in addition to mixings. At the Barcarès site (120 m deep), the high salinity in some layers appear to be related neither to present day seawater intrusion, nor to Salses-Leucate lagoonwater intrusion. Groundwater chemical composition thus highlights binary mixing between fresh groundwater and inherited salty water together with cation exchange processes, water–rock interactions and, locally, sedimentary organic matter mineralisation probably enhanced by pyrite oxidation. Finally, combining the results of this study and those of Caballero and Ladouche (2015

Tackling the salinity-pollution nexus in coastal aquifers from arid regions using nitrate and boron isotopes.

Science.gov (United States)

Re, V; Sacchi, E

2017-05-01

Salinization and nitrate pollution are generally ascertained as the main issues affecting coastal aquifers worldwide. In arid zones, where agricultural activities also result in soil salinization, both phenomena tend to co-exist and synergically contribute to alter groundwater quality, with severe negative impacts on human populations and natural ecosystems' wellbeing. It becomes therefore necessary to understand if and to what extent integrated hydrogeochemical tools can help in distinguishing among possible different salinization and nitrate contamination origins, in order to provide adequate science-based support to local development and environmental protection. The alluvial plain of Bou-Areg (North Morocco) extends over about 190 km 2 and is separated from the Mediterranean Sea by the coastal Lagoon of Nador. Its surface is covered for more than 60% by agricultural activities, although the region has been recently concerned by urban population increase and tourism expansion. All these activities mainly rely on groundwater exploitation and at the same time are the main causes of both aquifer and lagoon water quality degradation. For this reason, it was chosen as a case study representative of the typical situation of coastal aquifers in arid zones worldwide, where a clear identification of salinization and pollution sources is fundamental for the implementation of locally oriented remedies and long-term management strategies. Results of a hydrogeochemical investigation performed between 2009 and 2011 show that the Bou-Areg aquifer presents high salinity (often exceeding 100 mg/L in TDS) due to both natural and anthropogenic processes. The area is also impacted by nitrate contamination, with concentrations generally exceeding the WHO statutory limits for drinking water (50 mg/L) and reaching up to about 300 mg/L, in both the rural and urban/peri-urban areas. The isotopic composition of dissolved nitrates (δ 15 N NO3 and δ 18 O NO ) was used to constrain

An interesting use of 222 Rn in the study of the flow velocities in the coastal karstic aquifers

International Nuclear Information System (INIS)

Cesario, G.; Tinelli, R.

2001-01-01

Pollution phenomena which are more and more affecting groundwater, do require recovery actions which cannot fail to take into account the knowledge of filtration velocity, V f . Science literature, by now, includes a great deal of hydrogeological studies which stressed 222 Rn reliability as groundwater mobility indicator. In general, and not considering the nature of the aquifer, it was found that a higher mobility of waters corresponds to a higher radon content. Starting from such considerations and firmly considering experiences gathered so far within the coastal aquifer study, a swift method correlating groundwater filtration velocity to their radon content was implemented. This, later made it possible to obtain, by means of the 222 Rn isochores, isoradon map, valuable information on groundwater velocity even on far-reaching areas by only effecting few V f direct measurements. This method, then, was tested on the field in the Salento coastal area Torre S. Isidoro, where the aquifer presents hydraulic, chemical-physical parameters such eto be macroscopically considered as homogeneous. The validity of the method not only was it fully supported by this check, but also evidenced the reliability of information provided by the radon isochore maps with respect to the ones obtainable from the classical isothermal and isohaline map. Suggested method, then, offers a double advantage: to reduce to the minimum V f direct measurements, which are costly owing to the use of radioactive tracers, and to complete and/or confirm information collected from other maps. Finally, this study has also pointed out the presence of high 222 Rn in practically still groundwater, but subject to sea level continuous oscillations. Of course this work also relates to mechanisms this phenomenon is based on, as well as 222 Rn ratio [it

Tracing coastal and estuarine groundwater discharge sources in a complex faulted and fractured karst aquifer system

Science.gov (United States)

Lagomasino, D.; Price, R. M.

2013-05-01

Groundwater discharge can be an important input of water, nutrients and other constituents to coastal wetlands and adjacent marine areas, particularly in karst regions with little to no surface water flow. A combination of natural processes (e.g., sea-level rise and climate change) and anthropogenic pressures (e.g., urban growth and development) can alter the subterranean water flow to the coastline. For water management practices and environmental preservation to be better suited for the natural and human environment, a better understanding is needed of the hydrogeologic connectivity between the areas of fresh groundwater recharge and the coastal zone. The Yucatan peninsula has a unique tectonic and geologic history consisting of a Cretaceous impact crater, Miocene and Eocene tectonic plate movements, and multiple sea-level stands. These events have shaped many complex geologic formations and structures. The Sian Káan Biosphere Reserve (SKBR), a UNESCO World Heritage Site located along the Atlantic Ocean, overlaps two distinct hydrogeologic regions: the evaporate region to the south and south west, and the Holbox Fracture Zone to the north. These two regions create a complex network of layered, perched and fractured aquifers and an extensive groundwater cave network. The two regions are distinguished by bedrock mineralogical differences that can be used to trace shallow subsurface water from interior portions of the peninsula to the Bahia de la Ascension in the SKBR. The objective of this research was to use naturally occurring geochemical tracers (eg., Cl-, SO42-, HCO3-, K+, Mg2+, Na+, Ca2+ and stable isotopes of oxygen and hydrogen) to decipher the sources of groundwater flow through the coastal wetlands of the SKBR and into the Bahia de la Ascension. Surface water and groundwater samples were collected during two field campaigns in 2010 and 2012 within the coastal and estuarine waters of the SKBR. Additional water samples were collected at select cenotes along

Ecodesign Implementation and LCA

DEFF Research Database (Denmark)

McAloone, Tim C.; Pigosso, Daniela Cristina Antelmi

2018-01-01

implementation into manufacturing companies. Existing methods and tools for ecodesign implementation will be described, focusing on a multifaceted approach to environmental improvement through product development. Additionally, the use of LCA in an ecodesign implementation context will be further described...... in terms of the challenges and opportunities, together with the discussion of a selection of simplified LCA tools. Finally, a seven-step approach for ecodesign implementation which has been applied by several companies will be described....

Organisational LCA

DEFF Research Database (Denmark)

Martínez-Blanco, Julia; Finkbeiner, Matthias

2018-01-01

environmental performance over time, supporting strategic decisions, and informing corporate sustainability reporting. Several initiatives are on the way for the LCA of organisations: the UNEP/SETAC Life Cycle Initiative published the ‘Guidance on organizational LCA’, using ISO/TS 14072 as a backbone; moreover......, when the unit of analysis and the system boundaries are defined. Also, the approach for data collection needs to be fixed. Organisational LCA is a compilation and evaluation of the inputs, outputs and potential environmental impacts of the activities associated with the organisation adopting a life...... cycle perspective. It includes not only the facilities of the organisation itself, but also the activities upstream and downstream the value chain. This methodology is capable of serving multiple goals at the same time, like identifying environmental hotspots throughout the value chain, tracking...

Characterization of saline groundwater across the coastal aquifer of Israel as resource for desalination

Science.gov (United States)

Stein, Shaked; Russak, Amos; Sivan, Orit; Yechieli, Yospeh; Oren, Yoram; Kasher, Roni

2015-04-01

In arid countries with access to marine water seawater desalination is becoming an important water source in order to deal with the water scarcity and population growth. Seawater reverse osmosis (RO) facilities use open seawater intake, which requires pretreatment processes to remove particles in order to avoid fouling of the RO membrane. In small and medium size desalination facilities, an alternative water source can be saline groundwater in coastal aquifers. Using saline groundwater from boreholes near the shore as feed water may have the advantage of natural filtration and low organic content. It will also reduce operation costs of pretreatment. Another advantage of using groundwater is its availability in highly populated areas, where planning of large RO desalination plants is difficult and expensive due to real-estate prices. Pumping saline groundwater underneath the freshwater-seawater interface (FSI) might shift the interface towards the sea, thus rehabilitating the fresh water reservoirs in the aquifer. In this research, we tested the potential use of saline groundwater in the coastal aquifer of Israel as feed water for desalination using field work and desalination experiments. Specifically, we sampled the groundwater from a pumping well 100 m from the shore of Tel-Aviv and sea water from the desalination plant in Ashqelon, Israel. We used an RO cross flow system in a pilot plant in order to compare between the two water types in terms of permeate flux, permeate flux decline, salt rejection of the membrane and the fouling on the membrane. The feed, brine and fresh desalinated water from the outlet of the desalination system were chemically analyzed and compared. Field measurements of dissolved oxygen, temperature, pH and salinity were also conducted in situ. Additionally, SDI (silt density index), which is an important index for desalination, and total organic carbon that has a key role in organic fouling and development of biofouling, were measured and

Seawater intrusion in karstic, coastal aquifers: Current challenges and future scenarios in the Taranto area (southern Italy).

Science.gov (United States)

De Filippis, Giovanna; Foglia, Laura; Giudici, Mauro; Mehl, Steffen; Margiotta, Stefano; Negri, Sergio Luigi

2016-12-15

Mediterranean areas are characterized by complex hydrogeological systems, where management of freshwater resources, mostly stored in karstic, coastal aquifers, is necessary and requires the application of numerical tools to detect and prevent deterioration of groundwater, mostly caused by overexploitation. In the Taranto area (southern Italy), the deep, karstic aquifer is the only source of freshwater and satisfies the main human activities. Preserving quantity and quality of this system through management policies is so necessary and such task can be addressed through modeling tools which take into account human impacts and the effects of climate changes. A variable-density flow model was developed with SEAWAT to depict the "current" status of the saltwater intrusion, namely the status simulated over an average hydrogeological year. Considering the goals of this analysis and the scale at which the model was built, the equivalent porous medium approach was adopted to represent the deep aquifer. The effects that different flow boundary conditions along the coast have on the transport model were assessed. Furthermore, salinity stratification occurs within a strip spreading between 4km and 7km from the coast in the deep aquifer. The model predicts a similar phenomenon for some submarine freshwater springs and modeling outcomes were positively compared with measurements found in the literature. Two scenarios were simulated to assess the effects of decreased rainfall and increased pumping on saline intrusion. Major differences in the concentration field with respect to the "current" status were found where the hydraulic conductivity of the deep aquifer is higher and such differences are higher when Dirichlet flow boundary conditions are assigned. Furthermore, the Dirichlet boundary condition along the coast for transport modeling influences the concentration field in different scenarios at shallow depths; as such, concentration values simulated under stressed conditions

The origins of mercury found in the coastal aquifer of La Plana de Castellon (Eastern Spain)

International Nuclear Information System (INIS)

Lopez Gutierrez, J.; Garcia Menendez, O.; Ballesteros Navarro, B. J.

2010-01-01

Mercury was detected in the Plio-Quaternary detrital coastal aquifer of La Plana de Castellon in the second half of the 1990s in the area of Nules-Moncofar-Vall d'Uixo at concentrations of between 5 and 12 μg/L according to groundwater analysis. The most reliable hypothesis pointed originally to an anthropic origin, although no precise sources were identified. This paper describes the results of investigation undertaken by the Geological Survey of Spain (IGME) to either corroborate or reject this hypothesis. A wide sampling array was set up to collect groundwater, sediments, wastewaters and rainwater together with an exhaustive inventory of possible anthropic and natural sources of mercurial contamination. All these data were integrated into the geological and metallogenic context of the Plio-Quaternary sediments of the aquifer and the Mesozoic formations of its rim. The results have led us to arrive at a new hypothesis that points to a geogenic origin for the mercury, although is mobilisation would still appear be related to the intensive human exploitation of the groundwater in the area. (Author) 30 refs.

Transportation Life Cycle Assessment (LCA) Synthesis, Phase II

Science.gov (United States)

2018-04-24

The Transportation Life Cycle Assessment (LCA) Synthesis includes an LCA Learning Module Series, case studies, and analytics on the use of the modules. The module series is a set of narrated slideshows on topics related to environmental LCA. Phase I ...

Review of Aquifer Storage and Recovery Performance in the Upper Floridan Aquifer in Southern Florida

Science.gov (United States)

Reese, Ronald S.

2006-01-01

Introduction: Interest and activity in aquifer storage and recovery (ASR) in southern Florida has increased greatly during the past 10 to 15 years. ASR wells have been drilled to the carbonate Floridan aquifer system at 30 sites in southern Florida, mostly by local municipalities or counties located in coastal areas. The primary storage zone at these sites is contained within the brackish to saline Upper Floridan aquifer of the Floridan aquifer system. The strategy for use of ASR in southern Florida is to store excess freshwater available during the wet season in an aquifer and recover it during the dry season when needed for supplemental water supply. Each ASR cycle is defined by three periods: recharge, storage, and recovery. This fact sheet summarizes some of the findings of a second phase retrospective assessment of existing ASR facilities and sites.

Synergy of climate change and local pressures on saltwater intrusion in heterogeneous coastal aquifers

Science.gov (United States)

Abou Najm, M.; Safi, A.; El-Fadel, M.; Doummar, J.; Alameddine, I.

2016-12-01

The relative importance of climate change induced sea level rise on the salinization of a highly urbanized karstified coastal aquifers were compared with non-sustainable pumping. A 3D variable-density groundwater flow and solute transport model was used to predict the displacement of the saltwater-freshwater interface in a pilot aquifer located along the Eastern Mediterranean. The results showed that the influence of sea level rise was marginal when compared with the encroachment of salinity associated with anthropogenic abstraction. Model predictions of salinity mass and volumetric displacement of the interface corresponding to a long-term monthly transient model showed that the saltwater intrusion dynamic is highly sensitive to change in the abstraction rates which were estimated based on combinations of water consumption rates and population growth rates. Salinity encroachment, however, appeared to be more sensitive to water consumption rates in comparison to population growth rates, where a 50% increase in the rate of former led to four times more intrusion as compared to an equivalent increase in population growth rate over 20 years. Coupling both increase in population growth and increased consumption rates had a synergistic effect that aggravated the intrusion beyond the sum of the individual impacts. Adaptation strategies targeting a decrease in groundwater exploitation proved to be effective in retarding the intrusion.

Water quality in the surficial aquifer near agricultural areas in the Delaware Coastal Plain, 2014

Science.gov (United States)

Fleming, Brandon J.; Mensch, Laura L.; Denver, Judith M.; Cruz, Roberto M.; Nardi, Mark R.

2017-07-27

The U.S. Geological Survey, in cooperation with the Delaware Department of Agriculture, developed a network of wells to monitor groundwater quality in the surficial aquifer of the Delaware Coastal Plain. Well-drained soils, a flat landscape, and accessible water in the Delaware Coastal Plain make for a productive agricultural setting. As such, agriculture is one of the largest industries in the State of Delaware. This setting enables the transport of chemicals from agriculture and other land uses to shallow groundwater. Efforts to mitigate nutrient transport to groundwater by the implementation of agricultural best management practices (BMPs) have been ongoing for several decades. To measure the effectiveness of BMPs on a regional scale, a network of 48 wells was designed to measure shallow groundwater quality (particularly nitrate) over time near agricultural land in the Delaware Coastal Plain. Water characteristics, major ions, nutrients, and dissolved gases were measured in groundwater samples collected from network wells during fall 2014. Wells were organized into three groups based on their geochemical similarity and these groups were used to describe nitrate and chloride concentrations and factors that affect the variability among the groups. The results from this study are intended to establish waterquality conditions in 2014 to enable comparison of future conditions and evaluate the effectiveness of agricultural BMPs on a regional scale.

Aquifer recharging in South Carolina: radiocarbon in environmental hydrogeology

International Nuclear Information System (INIS)

Stone, P.A.; Knox, R.L.; Mathews, T.D.

1985-01-01

Radiocarbon activities of dissolved inorganic carbon (and tritium activities where infiltration rates are rapid and aquifers shallow) provide relatively unambiguous and inexpensive evidence for identification of significant recharge areas. Such evidence is for the actual occurrence of modern recharge in the aquifer and thus is less inferential than stratigraphic or potentiometric evidence. These underutilized isotopic techniques are neither arcane nor complex and have been more-or-less standardized by earlier researchers. In South Carolina, isotopic evidence has been used from both calcareous and siliceous sedimentary aquifers and fractured crystalline rock aquifers. The Tertiary limestone aquifer is shown not to be principally recharged in its subcrop area, unlike conditions assumed for many other sedimentary aquifers in southeastern United States, and instead receives considerable lateral recharge from interfingering updip Tertiary sand aquifers in the middle coastal plain. Induced recharging at Hilton Head Island is mixing ancient relict water and modern recharge water. Recharging to deeper portions of the Cretaceous Middendorf basal sand aquifer occurs at least as far coastward as the middle coastal plain, near sampling sites that stratigraphically appear to be confined. Pronounced mineralization of water in fractured rocks cannot be considered as evidence of ancient or relict ground water that is isolated from modern contaminants, some of these waters contain considerable radiocarbon and hydrogen-bomb tritium

Old groundwater in parts of the upper Patapsco aquifer, Atlantic Coastal Plain, Maryland, USA: Evidence from radiocarbon, chlorine-36 and helium-4

Science.gov (United States)

Plummer, Niel; Eggleston, John R.; Raffensperger, Jeff P.; Hunt, Andrew G.; Casile, Gerolamo C.; Andreasen, D.C.

2012-01-01

Apparent groundwater ages along two flow paths in the upper Patapsco aquifer of the Maryland Atlantic Coastal Plain, USA, were estimated using 14C, 36Cl and 4He data. Most of the ages range from modern to about 500 ka, with one sample at 117 km downgradient from the recharge area dated by radiogenic 4He accumulation at more than one Ma. Last glacial maximum (LGM) water was located about 20 km downgradient on the northern flow path, where the radiocarbon age was 21.5 ka, paleorecharge temperatures were 0.5–1.5  °C (a maximum cooling of about 12 °C relative to the modern mean annual temperature of 13 °C), and Cl–, Cl/Br, and stable isotopes of water were minimum. Low recharge temperatures (typically 5–7 °C) indicate that recharge occurred predominantly during glacial periods when coastal heads were lowest due to low sea-level stand. Flow velocities averaged about 1.0 m a–1 in upgradient parts of the upper Patapsco aquifer and decreased from 0.13 to 0.04 m a–1 at 40 and 80 km further downgradient, respectively. This study demonstrates that most water in the upper Patapsco aquifer is non-renewable on human timescales under natural gradients, thus highlighting the importance of effective water-supply management to prolong the resource.

Integrating an artificial intelligence approach with k-means clustering to model groundwater salinity: the case of Gaza coastal aquifer (Palestine)

Science.gov (United States)

Alagha, Jawad S.; Seyam, Mohammed; Md Said, Md Azlin; Mogheir, Yunes

2017-12-01

Artificial intelligence (AI) techniques have increasingly become efficient alternative modeling tools in the water resources field, particularly when the modeled process is influenced by complex and interrelated variables. In this study, two AI techniques—artificial neural networks (ANNs) and support vector machine (SVM)—were employed to achieve deeper understanding of the salinization process (represented by chloride concentration) in complex coastal aquifers influenced by various salinity sources. Both models were trained using 11 years of groundwater quality data from 22 municipal wells in Khan Younis Governorate, Gaza, Palestine. Both techniques showed satisfactory prediction performance, where the mean absolute percentage error (MAPE) and correlation coefficient ( R) for the test data set were, respectively, about 4.5 and 99.8% for the ANNs model, and 4.6 and 99.7% for SVM model. The performances of the developed models were further noticeably improved through preprocessing the wells data set using a k-means clustering method, then conducting AI techniques separately for each cluster. The developed models with clustered data were associated with higher performance, easiness and simplicity. They can be employed as an analytical tool to investigate the influence of input variables on coastal aquifer salinity, which is of great importance for understanding salinization processes, leading to more effective water-resources-related planning and decision making.

Mapping and characterization of LCA networks

DEFF Research Database (Denmark)

Bjørn, Anders; Owsianiak, Mikolaj; Laurent, Alexis

2013-01-01

Purpose: The aims of this study were to provide an up-todate overview of global, regional and local networks supporting life cycle thinking and to characterize them according to their structure and activities. Methods: Following a tentative life cycle assessment (LCA) network definition, a mapping......: The provided list of LCA networks is currently the most comprehensive, publicly available mapping. We believe that the results of this mapping can serve as a basis for deciding where priorities should be set to increase the dissemination and development of LCA worldwide. In this aim, we also advocate...... was performed based on (1) a literature search, (2) a web search and (3) an inquiry to stakeholders distributed via the two largest LCA fora. Networks were characterized based on responses from a survey. Results and discussion: We identified 100 networks, of which 29 fulfilled all six criteria composing our...

LCA of Solid Waste Management Systems

DEFF Research Database (Denmark)

Bakas, Ioannis; Laurent, Alexis; Clavreul, Julie

2018-01-01

The chapter explores the application of LCA to solid waste management systems through the review of published studies on the subject. The environmental implications of choices involved in the modelling setup of waste management systems are increasingly in the spotlight, due to public health...... concerns and new legislation addressing the impacts from managing our waste. The application of LCA to solid waste management systems, sometimes called “waste LCA”, is distinctive in that system boundaries are rigorously defined to exclude all life cycle stages except from the end-of-life. Moreover...... LCA on solid waste systems....

Impact of Varying Wave Conditions on the Mobility of Arsenic in a Nearshore Aquifer on the Great Lakes

Science.gov (United States)

Rakhimbekova, S.; O'Carroll, D. M.; Robinson, C. E.

2017-12-01

Groundwater-coastal water interactions play an important role in controlling the behavior of inorganic chemicals in nearshore aquifers and the subsequent flux of these chemicals to receiving coastal waters. Previous studies have shown that dynamic groundwater flows and water exchange across the sediment-water interface can set up strong geochemical gradients and an important reaction zone in a nearshore aquifer that affect the fate of reactive chemicals. There is limited understanding of the impact of transient coastal forcing such as wave conditions on groundwater dynamics and geochemistry in a nearshore aquifer. The goal of this study was to assess the impact of intensified wave conditions on the behavior of arsenic in a nearshore aquifer and to determine the hydrological and geochemical factors controlling its fate and ultimate delivery to receiving coastal waters. Field investigations were conducted over the period of intensified wave conditions on a freshwater beach on Lake Erie, Canada. High spatial resolution aqueous and sediment sampling was conducted to characterize the subsurface distribution of inorganic species in the nearshore aquifer. Numerical groundwater flow and transport simulations were conducted to evaluate wave-induced perturbations in the flow dynamics including characterizing changes in the groundwater flow recirculations in the nearshore aquifer. The combination of field data and numerical simulations reveal that varying wave conditions alter groundwater flows and set up geochemical transition zones within the aquifer resulting in the release and sequestration of arsenic. Interactions between oxic surface water, mildly reducing shallow groundwater, and reducing sulfur- and iron-rich deep groundwater promote dynamic iron, sulfur and manganese cycling which control the mobility of arsenic in the aquifer. The findings of this study have potential implications for the fate and transport of other reactive chemicals (e.g. phosphorus, mercury) in

A Search for Freshwater in the Saline Aquifers of Coastal Bangladesh

Science.gov (United States)

Peters, C.; Hornberger, G. M.

2017-12-01

Can we locate pockets of freshwater amidst brackish groundwater in remote villages in Bangladesh? This study explores what we can infer about local groundwater-surface water (GW-SW) interactions in the polders of coastal Bangladesh. In this underdeveloped region, the shallow groundwater is primarily brackish with unpredictable apportioning of freshwater pockets. We use transects of piezometers, cores, electromagnetic induction, and water chemistry surveys to explore two sources of potential fresh groundwater: (1) tidal channel-aquifer exchange and (2) meteoric recharge. Freshwater is difficult to find due to disparate subsurface lithology, asymmetrical tidal dynamics, extreme seasonal fluctuations in rainfall, and limited field data. Observations suggest substantial lateral variability in shallow subsurface conductivity profiles as well as tidal pressure signals in piezometers. Nevertheless, active exchange of freshwater may be limited due to low permeability of banks and surface sediments limits. Small scale heterogeneity in delta formation likely caused much of the groundwater salinity variation. Without adequate ground truthing of groundwater quality, the ability to deduce the exact location of freshwater pockets may be restricted.

Spatial Distribution of Field Physico-Chemical Parameters in the Vulcano Island (Italy Coastal Aquifer: Volcanological and Hydrogeological Implications

Directory of Open Access Journals (Sweden)

Paolo Madonia

2015-06-01

Full Text Available Vulcano, the southernmost of the Aeolian island arc (Italy, is characterized by a shallow coastal aquifer resulting from the mixing of seawater, meteoric recharge and volcanogenic fluids. The aquifer has been intensively studied during the last decades, but a comprehensive hydrogeological model has never been developed due to the lack of direct information about the litho-stratigraphic columns of the wells and the depth of water bearing levels. We present and discuss here the time and spatial analysis of water table elevation, temperature and electric conductivity data, acquired during the last 20 years in 33 wells located at Vulcano Island, with the aim of developing a groundwater circulation scheme able to fit the field observations. We retrieved a circulation scheme characterized by an intricate geometry of flow paths driven by horizontal and vertical permeability variations, accounting for the strong variability of geochemical data evidenced in this area by the related scientific literature. Extending these results to a general context, particular care must be taken in approaching the study of aquifers in volcanic islands, because a strong, small spatial scale variability of the hydrogeochemical parameters is expected, and a reliable knowledge of the local conditions is required for developing successful groundwater circulation schemes.

Risk assessment and management of an oil contaminated aquifer

International Nuclear Information System (INIS)

Braxein, A.; Daniels, H.; Rouve, G.; Rubin, H.

1991-01-01

This paper concerns the provision of the basic information needed for the decision making process regarding the remedial measures leading to reutilization of an oil contaminated aquifer. The study refers to the case history of jet fuel contamination of an aquifer comprising part of the coastal aquifer of Israel. Due to that contamination two major water supply wells were abandoned. This study examines the use of numerical simulations in order to restore the contamination history of the aquifer. Such simulations also provide quantitative information needed for the decision making process regarding the future management of the contaminated aquifer

LCA of Energy Systems

DEFF Research Database (Denmark)

Laurent, Alexis; Espinosa Martinez, Nieves; Hauschild, Michael Zwicky

2018-01-01

Energy systems are essential in the support of modern societies’ activities, and can span a wide spectrum of electricity and heat generation systems and cooling systems. Along with their central role and large diversity, these systems have been demonstrated to cause serious impacts on human health...... , ecosystems and natural resources. Over the past two decades, energy systems have thus been the focus of more than 1000 LCA studies, with the aim to identify and reduce these impacts. This chapter addresses LCA applications to energy systems for generation of electricity and heat . The chapter gives insight...

Groundwater reorganization in the Floridan aquifer following Holocene sea-level rise

OpenAIRE

Morrissey, SK; Clark, JF; Bennett, M; Richardson, E; Stute, M

2010-01-01

Sea-level fluctuations, particularly those associated with glacial-interglacial cycles, can have profound impacts on the flow and circulation of coastal groundwater: the water found at present in many coastal aquifers may have been recharged during the last glacial period, when sea level was over 100 m lower than present, and thus is not in equilibrium with present recharge conditions. Here we show that the geochemistry of the groundwater found in the Floridan Aquifer System in south Florida ...

Coastal ground water at risk - Saltwater contamination at Brunswick, Georgia and Hilton Head Island, South Carolina

Science.gov (United States)

Krause, Richard E.; Clarke, John S.

2001-01-01

IntroductionSaltwater contamination is restricting the development of ground-water supply in coastal Georgia and adjacent parts of South Carolina and Florida. The principal source of water in the coastal area is the Upper Floridan aquifer—an extremely permeable and high-yielding aquifer—which was first developed in the late 1800s. Pumping from the aquifer has resulted in substantial ground-water-level decline and subsequent saltwater intrusion of the aquifer from underlying strata containing highly saline water at Brunswick, Georgia, and with encroachment of sea-water into the aquifer at the northern end of Hilton Head Island, South Carolina. The saltwater contamination at these locations has constrained further development of the Upper Floridan aquifer in the coastal area and has created competing demands for the limited supply of freshwater. The Georgia Department of Natural Resources, Georgia Environmental Protection Division (GaEPD) has restricted permitted withdrawal of water from the Upper Floridan aquifer in parts of the coastal area (including the Savannah and Brunswick areas) to 1997 rates, and also has restricted additional permitted pumpage in all 24 coastal area counties to 36 million gallons per day above 1997 rates. These actions have prompted interest in alternative management of the aquifer and in the development of supplemental sources of water supply including those from the shallower surficial and upper and lower Brunswick aquifers and from the deeper Lower Floridan aquifer.

Underground dams for irrigation supplies in coastal limestone aquifer, Okinawa, Japan

Science.gov (United States)

Yasumoto, J.; Nakano, T.; Nawa, N.

2011-12-01

The use of underground dams to store water in regions with arid or tropical climates is a method that has received considerable attention in the last few decades. And now, for the tropical and subtropical islands that are highly vulnerable to climate change underground dams have been attracting attention again as a method of groundwater management. Okinawa Prefecture is Japan's southernmost prefecture, which consists of hundreds of islands in a chain over 1,000 km long, called the Ryukyu Islands which extend southwest from Kyushu to Taiwan. The national irrigation project of the Ryukyu Islands has been carried out, and several underground dams have been constructed. The Komesu and Giiza underground dams are first full scale underground dam facilities constructed for irrigation in Japan. The Komesu underground dam is a salt-water proof type. It prevents salt-water intrusion and provides storage fresh-water for irrigation in coastal limestone aquifer. Giiza underground dam is a dam up type for storage of fresh-water. These groundwater reservoirs are located in the coastal region of southern part of Okinawa (main island), where Ryukyu limestone is extensively distributed. We studied the behaviour of groundwater flow, saltwater intrusion and nitrate nitrogen (NO3-N) in groundwater in this region by using observation data of groundwater and springs through long term (from 1993 to 2010) monitoring. And, a groundwater flow and salt-water intrusion analysis have been conducted with three dimensional numerical model applied to these dam reservoir areas. The MODFLOW-NWT with SWI code and PEST was used to simulate the complex groundwater flow patterns. Through the comparison with simulation and observed data, it was concluded that the cut off wall of underground dams effectively stores the groundwater and prevents the salt-water intrusion in the reservoir areas. The observed groundwater levels at the reservoir areas were almost reproduced by the numerical model, but there

Use of a time-domain electromagnetic method with geochemical tracers to explore the salinity anomalies in a small coastal aquifer in north-eastern Tunisia

Science.gov (United States)

Chekirbane, Anis; Tsujimura, Maki; Kawachi, Atsushi; Lachaal, Fethi; Isoda, Hiroko; Tarhouni, Jamila

2014-12-01

The study area is a small coastal plain in north-eastern Tunisia. It is drained by an ephemeral stream network and is subject to several pollutant discharges such as oilfield brine coming from a neighboring oil company and wastewater from Somâa city, located in the upstream of the plain. Furthermore, a hydraulic head near the coastal part of the aquifer is below sea level, suggesting that seawater intrusion may occur. A time-domain electromagnetic (TDEM) survey, based on 28 soundings, was conducted in Wadi Al Ayn and Daroufa plains to delineate the saline groundwater. Based on longitudinal and transversal resistivity two-dimensional pseudosections calibrated with boring data, the extent of saline water was identified. Geochemical tracers were combined with the resistivity dataset to differentiate the origin of groundwater salinization. In the upstream part of the plain, the infiltration of oilfield brine through the sandy bed of Wadi Al Ayn seems to have a considerable effect on groundwater salinization. However, in the coastal part of the aquifer, groundwater salinization is due to seawater intrusion and the saltwater is reaching an inland extent around 1.3 km from the shoreline. The contribution ratios of saline water bodies derived from the inverted chloride data vary for the oilfield brine from 1 to 13 % and for the seawater from 2 to 21 %.

Defining a conceptual model for the coastal aquifers of Mediterranean islands, an example from Corsica (France)

Science.gov (United States)

Santoni, Sebastien; Garel, Emilie; Huneau, Frederic

2016-04-01

A hydrochemical and isotope study was conducted to identify the flow paths, the recharge areas and the geochemical processes governing the evolution of groundwater in a Mediterranean carbonate coastal aquifer. The study is expected to improve the hydrogeological conceptual model based on environmental tracer investigations tools to characterise and quantify the aquifer system of Bonifacio. The groundwater resource represents the unique drinking water resource of the southern Corsica and the region faces a high pressures over the groundwater resource during the touristic period (2,000,000 tourists per year). A well-documented description of the geology and structure of this basin was the starting point for a detailed hydrogeochemical and isotopic study at the aquifer scale. A hydrochemical (physico-chemical parameters, major ions) and isotope (δ2H, δ18O, 3H) survey of rainwater and groundwater has been carried out monthly during almost two years. A local meteoric water line has been defined and marine, terrestrial and anthropogenic influences on the recharge water hydrochemistry have been described. Preferential recharge during autumn/winter of rainfall is observed and a depletion in the isotopic signature for some groundwater samples suggests a recharge in higher altitude from the surrounding granites. A modification of the input signal during infiltration through the unsaturated zone appears and the groundwater hydrochemistry displays differential variations in time and space, with the presence of inertial water bodies in the lower aquifer mainly. In this context, CFCs (CFC-11, CFC-12, CFC-113) and SF6 were used to evaluate groundwater residence time. CFCs have been relevant despite the presence of a deep unsaturated zone and the computed rate of groundwater renewal is pluriannual to multi-decadal. Natural SF6 was found in granites and has been used as a direct tracer of groundwater origin, highlighting its role in the aquifer lateral recharge. Strontium

Effects of Projected Future Climate Change on Groundwater Recharge and Storage for Two Coastal Aquifers in Guanacaste Province, Costa Rica

Science.gov (United States)

Kolb, C.

2017-12-01

Climate change is expected to pose a significant threat to water resources in the future. Guanacaste Province, located in northwestern Costa Rica, has a unique climate that is influenced by the Pacific Ocean and Caribbean Sea, as well as the Central Cordillera mountain range. Although the region experiences a marked rainy season between May and November, the hot, dry summers often stress water resources. Climate change projections suggest increased temperatures and reduced precipitation for the region, which will further stress water supplies. This study focuses on the effects of climate change on groundwater resources for two coastal aquifers, Potrero and Brasilito. The UZF model package coupled with the finite difference groundwater flow model MODFLOW were used to evaluate the effect of climate change on groundwater recharge and storage. A potential evapotranspiration model was used to estimate groundwater infiltration rates used in the MODFLOW model. Climate change projections for temperature, precipitation, and sea level rise were used to develop climate scenarios, which were compared to historical data. Preliminary results indicate that climate change could reduce future recharge, especially during the dry season. Additionally, the coastal aquifers are at increased risk of reduced storage and increased salinization due to the reductions in groundwater recharge and sea level rise. Climate change could also affect groundwater quality in the region, disrupting the ecosystem and impairing a primary source of drinking water.

Joining direct and indirect inverse calibration methods to characterize karst, coastal aquifers

Science.gov (United States)

De Filippis, Giovanna; Foglia, Laura; Giudici, Mauro; Mehl, Steffen; Margiotta, Stefano; Negri, Sergio

2016-04-01

this reason, a joint procedure is proposed by merging both direct and indirect approaches, thus taking advantage of their strengths, first among them the possibility to get a hydraulic head distribution all over the domain, instead of a zonation. Pros and cons of such an integrated methodology, so far unexplored to the authors' knowledge, are derived after application to a highly heterogeneous karst, coastal aquifer located in southern Italy.

Hydrogeological and multi-isotopic approach to define nitrate pollution and denitrification processes in a coastal aquifer (Sardinia, Italy)

Science.gov (United States)

Pittalis, Daniele; Carrey, Raul; Da Pelo, Stefania; Carletti, Alberto; Biddau, Riccardo; Cidu, Rosa; Celico, Fulvio; Soler, Albert; Ghiglieri, Giorgio

2018-02-01

Agricultural coastal areas are frequently affected by the superimposition of various processes, with a combination of anthropogenic and natural sources, which degrade groundwater quality. In the coastal multi-aquifer system of Arborea (Italy)—a reclaimed morass area identified as a nitrate vulnerable zone, according to Nitrate Directive 91/676/EEC—intensive agricultural and livestock activities contribute to substantial nitrate contamination. For this reason, the area can be considered a bench test for tuning an appropriate methodology aiming to trace the nitrate contamination in different conditions. An approach combining environmental isotopes, water quality and hydrogeological indicators was therefore used to understand the origins and attenuation mechanisms of nitrate pollution and to define the relationship between contaminant and groundwater flow dynamics through the multi-aquifer characterized by sandy (SHU), alluvial (AHU), and volcanic hydrogeological (VHU) units. Various groundwater chemical pathways were consistent with both different nitrogen sources and groundwater dynamics. Isotope composition suggests a mixed source for nitrate (organic and synthetic fertilizer), especially for the AHU and SHU groundwater. Moreover, marked heterotrophic denitrification and sulfate reduction processes were detected; although, for the contamination related to synthetic fertilizer, the attenuation was inefficient at removing NO3 - to less than the human consumption threshold of 50 mg/L. Various factors contributed to control the distribution of the redox processes, such as the availability of carbon sources (organic fertilizer and the presence of lagoon-deposited aquitards), well depth, and groundwater flow paths. The characterization of these processes supports water-resource management plans, future actions, and regulations, particularly in nitrate vulnerable zones.

Archive of Digital Boomer Seismic Reflection Data Collected During USGS Field Activity 96LCA04 in Lakes Mabel and Starr, Central Florida, August 1996

Science.gov (United States)

Harrison, Arnell S.; Dadisman, Shawn V.; Swancar, Amy; Tihansky, Ann B.; Flocks, James G.; Wiese, Dana S.

2008-01-01

In August of 1996, the U.S. Geological Survey conducted geophysical surveys of Lakes Mabel and Starr, central Florida, as part of the Central Highlands Lakes project, which is part of a larger USGS Lakes and Coastal Aquifers (LCA) study. This report serves as an archive of unprocessed digital boomer seismic reflection data, trackline maps, navigation files, Geographic Information System (GIS) files, observer's logbook; and formal Federal Geographic Data Committee (FGDC) metadata. Filtered and gained (a relative increase in signal amplitude) digital images of the seismic profiles are also provided. Refer to the Acronyms page for expansions of acronyms and abbreviations used in this report. For detailed information about the hydrologic setting of Lake Starr and the interpretation of some of these seismic reflection data, see Swancar and others (2000) at http://fl.water.usgs.gov/publications/Abstracts/wri00_4030_swancar.html. The archived trace data are in standard Society of Exploration Geophysicists (SEG) SEG-Y format (Barry and others, 1975) and may be downloaded and processed with commercial or public domain software such as Seismic Unix (SU). Example SU processing scripts and USGS software for viewing the SEG-Y files (Zihlman, 1992) are also provided. The USGS Florida Integrated Science Center (FISC) - St. Petersburg assigns a unique identifier to each cruise or field activity. For example, 96LCA04 tells us the data were collected in 1996 for the Lakes and Coastal Aquifers (LCA) study and the data were collected during the fourth field activity for that project in that calendar year. Refer to http://walrus.wr.usgs.gov/infobank/programs/html/definition/activity.html for a detailed description of the method used to assign the field activity ID. The boomer plate is an acoustic energy source that consists of capacitors charged to a high voltage and discharged through a transducer in the water. The transducer is towed on a sled floating on the water surface and when

Hurricane Ingrid and Tropical Storm Hanna's effects on the salinity of the coastal aquifer, Quintana Roo, Mexico

Science.gov (United States)

Kovacs, Shawn E.; Reinhardt, Eduard G.; Stastna, Marek; Coutino, Aaron; Werner, Christopher; Collins, Shawn V.; Devos, Fred; Le Maillot, Christophe

2017-08-01

There is a lack of information on aquifer dynamics in anchialine systems, especially in the Yucatán Peninsula of Mexico. Most of our knowledge is based on ;spot; measurements of the aquifer with no long-term temporal monitoring. In this study spanning four years (2012-2016), sensors (water depth and conductivity (salinity)) were deployed and positioned (-9 and -10 m) in the meteoric Water Mass (WM) close to the transition with the marine WM (halocline) in 2 monitoring sites within the Yax Chen cave system to investigate precipitation effects on the salinity of the coastal aquifer. The results show variation in salinity (95 mm) such as Hurricane Ingrid (2013) and Tropical Storm Hanna (2014) shows meteoric water mass salinity rapidly increasing (approx. 6.39 to >8.6 ppt), but these perturbations have a shorter duration (weeks and days). Wavelet analysis of the salinity record indicates seasonal mixing effects in agreement with the wet and dry periods, but also seasonal effects of tidal mixing (meteoric and marine water masses) occurring on shorter time scales (diurnal and semi-diurnal). These results demonstrate that the salinity of the freshwater lens is influenced by precipitation and turbulent mixing with the marine WM. The salinity response is scaled with precipitation; larger more intense rainfall events (>95 mm) create a larger response in terms of the magnitude and duration of the salinity perturbation (>1 ppt). The balance of precipitation and its intensity controls the temporal and spatial patterning of meteoric WM salinity.

Quantifying uncertainty in LCA-modelling of waste management systems

DEFF Research Database (Denmark)

Clavreul, Julie; Guyonnet, D.; Christensen, Thomas Højlund

2012-01-01

Uncertainty analysis in LCA studies has been subject to major progress over the last years. In the context of waste management, various methods have been implemented but a systematic method for uncertainty analysis of waste-LCA studies is lacking. The objective of this paper is (1) to present...... the sources of uncertainty specifically inherent to waste-LCA studies, (2) to select and apply several methods for uncertainty analysis and (3) to develop a general framework for quantitative uncertainty assessment of LCA of waste management systems. The suggested method is a sequence of four steps combining...

Future-Oriented LCA

DEFF Research Database (Denmark)

Olsen, Stig Irving; Borup, Mads; Andersen, Per Dannemand

2018-01-01

LCA is often applied for decision-making that concerns actions reaching near or far into the future. However, traditional life cycle assessment methodology must be adjusted for the prospective and change-oriented purposes, but no standardised way of doing this has emerged yet. In this chapter some...... challenges are described and some learnings are derived. Many of the future-oriented LCAs published so far perform relatively short-term prediction of simple comparisons. But for more long-term time horizons foresight methods can be of help. Scenarios established by qualified experts about future...... technological and economic developments are indispensable in future technology assessments. The uncertainties in future-oriented LCAs are to a large extent qualitative and it is important to emphasise that LCA of future technologies will provide a set of answers and not ‘the’ answer....

Numerical analysis of the hydrogeologic controls in a layered coastal aquifer system, Oahu, Hawaii, USA

Science.gov (United States)

Oki, Delwyn S.; Souza, William R.; Bolke, Edward L.; Bauer, Glenn R.

The coastal aquifer system of southern Oahu, Hawaii, USA, consists of highly permeable volcanic aquifers overlain by weathered volcanic rocks and interbedded marine and terrestrial sediments of both high and low permeability. The weathered volcanic rocks and sediments are collectively known as caprock, because they impede the free discharge of groundwater from the underlying volcanic aquifers. A cross-sectional groundwater flow and transport model was used to evaluate the hydrogeologic controls on the regional flow system in southwestern Oahu. Controls considered were: (a) overall caprock hydraulic conductivity; and (b) stratigraphic variations of hydraulic conductivity in the caprock. Within the caprock, variations in hydraulic conductivity, caused by stratigraphy or discontinuities of the stratigraphic units, are a major control on the direction of groundwater flow and the distribution of water levels and salinity. Results of cross-sectional modeling confirm the general groundwater flow pattern that would be expected in a layered coastal system. Groundwater flow is: (a) predominantly upward in the low-permeability sedimentary units; and (b) predominantly horizontal in the high-permeability sedimentary units. Résumé Le système aquifère littoral du sud d'Oahu (Hawaii, États-Unis) est constitué par des aquifères de terrains volcaniques très perméables, recouverts par des roches volcaniques altérées, et interstratifiés avec des sédiments marins et continentaux de perméabilité aussi bien forte que faible. Les roches volcaniques altérées et les sédiments sont globalement considérés comme une couverture, parce qu'ils s'opposent à l'écoulement de l'eau souterraine provenant des aquifères volcaniques sous-jacents. Les contrôles hydrogéologiques sur le système aquifère régional du sud-ouest d'Oahu ont étéévaluées au moyen d'un modèle d'écoulement et de transport sur une section transversale. Ces contrôles prennent en compte la conductivit

Optimization of Design of Aquifer Storage and Recovery System (ASTR) for Enhanced Infiltration Rate with Reduced Cost at the Coastal Aquifers of South-Western Bangladesh

Science.gov (United States)

Nawrin, N.; Ahmed, K. M.; Rahman, M. M.

2016-12-01

Increasing salinity of natural drinking water sources has been reported as one of the many problems that affect low-income countries. Safe potable water sources in coastal Bangladesh have become contaminated by varying degrees of salinity due to saltwater intrusion, cyclone and storm surges and increased shrimp and crab farming along the coastal areas. This crisis is also exacerbated owing to climate change. The problem of salinity can have serious implications to public health. Here Managed Aquifer Recharge (MAR) has been ascertained as a better solution to overcome the fresh water shortage in the coastal belt of Bangladesh in terms of groundwater quality improvement and supply fresh water even during the dry period. 19 MAR systems have been built and tested in the area for providing community water supply by way of creating freshwater buffer zone in the brackish aquifers through artificial recharge of pond or rooftop rainwater. These existing ASTR schemes consist of sand filtration tank with 4 to 6 large diameter infiltration wells filled with sorted gravel. These larger diameter recharge wells make the construction and maintenance expensive and little difficult for the rural communities. Therefore, modification of design is required for enhancing infiltration rates with reduced costs. As the design of the existing MAR system have confronted some problems, the details of design, construction and performance have been studied from previous investigations and a new modified ASTR scheme has been demonstrated to amplify the infiltration rate along with monitoring scheme. Smaller 4 inch diameter empty recharge wells and PVC screen have been used in the newly developed design. Daily infiltration rate has been increased to 8 to 10 m3/d compared to 4 to 6 m3/d in the old design. Three layered sand filtration tank has been prepared by modification of an abandoned PSF. Time needed for lowering EC to acceptable limits has been found to be significantly lower than the pre

Trends and transformation of nutrients and pesticides in a Coastal Plain aquifer system, United States

Science.gov (United States)

Denver, J.M.; Tesoriero, A.J.; Barbaro, J.R.

2010-01-01

Four local-scale sites in areas with similar corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] agriculture were studied to determine the effects of different hydrogeologic settings of the Northern Atlantic Coastal Plain (NACP) on the transport of nutrients and pesticides in groundwater. Settings ranged from predominantly well-drained soils overlying thick, sandy surficial aquifers to predominantly poorly drained soils with complex aquifer stratigraphy and high organic matter content. Apparent age of groundwater, dissolved gases, N isotopes, major ions, selected pesticides and degradates, and geochemical environments in groundwater were studied. Agricultural chemicals were the source of most dissolved ions in groundwater. Specific conductance was strongly correlated with reconstructed nitrate (the sum of N in nitrate and N gas) (R2 = 0.81, p < 0.0001), and is indicative of the relative degree of agricultural effects on groundwater. Trends in nitrate were primarily related to changes in manure and fertilizer use at the well-drained sites where aquifer conditions were consistently oxic. Nitrate was present in young groundwater but completely removed over time through denitrification at the poorly drained sites where there were variations in chemical input and in geochemical environment. Median concentrations of atrazine (6-chloro-N-ethyl-N'-(1- methylethyl)-1,3,5-triazine-2,4-diamine), metolachlor (2-chloro-N-(2-ethyl-6- methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide), and some of their common degradates were higher at well-drained sites than at poorly drained sites, with concentrations of degradates generally higher than those of the parent compounds at all sites. An increase in the percentage of deethylatrazine to total atrazine over time at one well-drained site may be related to changes in manure application. Copyright ?? 2010 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

Groundwater availability in the Atlantic Coastal Plain of North and South Carolina

Science.gov (United States)

Campbell, Bruce G.; Coes, Alissa L.

2010-01-01

The Atlantic Coastal Plain aquifers and confining units of North and South Carolina are composed of crystalline carbonate rocks, sand, clay, silt, and gravel and contain large volumes of high-quality groundwater. The aquifers have a long history of use dating back to the earliest days of European settlement in the late 1600s. Although extensive areas of some of the aquifers have or currently (2009) are areas of groundwater level declines from large-scale, concentrated pumping centers, large areas of the Atlantic Coastal Plain contain substantial quantities of high-quality groundwater that currently (2009) are unused. Groundwater use from the Atlantic Coastal Plain aquifers in North Carolina and South Carolina has increased during the past 60 years as the population has increased along with demands for municipal, industrial, and agricultural water needs. While North Carolina and South Carolina work to increase development of water supplies in response to the rapid growth in these coastal populations, both States recognize that they are facing a number of unanswered questions regarding availability of groundwater supplies and the best methods to manage these important supplies. An in-depth assessment of groundwater availability of the Atlantic Coastal Plain aquifers of North and South Carolina has been completed by the U.S. Geological Survey Groundwater Resources Program. This assessment includes (1) a determination of the present status of the Atlantic Coastal Plain groundwater resources; (2) an explanation for how these resources have changed over time; and (3) development of tools to assess the system's response to stresses from potential future climate variability. Results from numerous previous investigations of the Atlantic Coastal Plain by Federal and State agencies have been incorporated into this effort. The primary products of this effort are (1) comprehensive hydrologic datasets such as groundwater levels, groundwater use, and aquifer properties; (2) a

Groundwater Quality and Quantity in a Coastal Aquifer Under High Human Pressure: Understand the Aquifer Functioning and the Social Perception of Water Use for a Better Water Management. Example of Recife (PE, Brazil)

Science.gov (United States)

Petelet-Giraud, E.; Cary, L.; Bertrand, G.; Alves, L. M.; Cary, P.; Giglio-Jacquemot, A.; Aquilina, L.; Hirata, R.; Montenegro, S.; Aurouet, A.; Franzen, M.; Chatton, E.

2015-12-01

The Recife Metropolitan Region is a typical "hot spot" illustrating the problems of southern countries on water issues inducing high pressures on water resources both on quantity and quality in the context of global social and environmental changes. This study is based on an interdisciplinary approach, coupling "hard" geosciences together with "soft" social sciences with the aim to study the human impact on coastal aquifers in a context of overexploitation to improve the existing water management tools. By revisiting the geological and hydrogeological conceptual models, field campaigns of groundwater and surface water sampling and analysis, and of interviews of different actors on the theme of water supply and management in Recife Metropolitan Region, the main results can be summarized as follows: (1) The recharge of the deep strategic confined aquifers is very limited resulting in water level decrease (up to -90m in 25y) due to overexploitation. (2) Groundwater residence time in these deep aquifers is over 10,000 years. (3) The natural upward flux of these confined aquifers is observed inland, but is reversed in the heavily populated areas along the coast leading to mixing with modern groundwater coming from the shallow aquifers. (4) Groundwater salinization is inherited from the Pleistocene marine transgression, only partly diluted by the recharge through the mangroves during the subsequent regression phase. Today, leakage from surficial aquifers induces local salinization. (5) Local climatic scenarios predict a reduction of rainfall volume of 20% together with an increase of sea level (18-59cm by 2100). (5) The Public authorities tend to deny the difficulties that people, especially those in precarious situation, are confronted with regarding water, especially in times of drought. The COQUEIRAL research project is financially supported by ANR (ANR-11-CEPL-012); FACEPE (APQ-0077-3.07/11); FAPESP (2011/50553-0

LCA of Chemicals and Chemical Products

DEFF Research Database (Denmark)

Fantke, Peter; Ernstoff, Alexi

2018-01-01

This chapter focuses on the application of Life Cycle Assessment (LCA) to evaluate the environmental performance of chemicals as well as of products and processes where chemicals play a key role. The life cycle stages of chemical products, such as pharmaceuticals drugs or plant protection products......, are discussed and differentiated into extraction of abiotic and biotic raw materials, chemical synthesis and processing, material processing, product manufacturing, professional or consumer product use, and finally end-of-life . LCA is discussed in relation to other chemicals management frameworks and concepts...... including risk assessment , green and sustainable chemistry , and chemical alternatives assessment. A large number of LCA studies focus on contrasting different feedstocks or chemical synthesis processes, thereby often conducting a cradle to (factory) gate assessment. While typically a large share...

Groundwater reorganization in the Floridan aquifer following Holocene sea-level rise

Science.gov (United States)

Morrissey, Sheila K.; Clark, Jordan F.; Bennett, Michael; Richardson, Emily; Stute, Martin

2010-10-01

Sea-level fluctuations, particularly those associated with glacial-interglacial cycles, can have profound impacts on the flow and circulation of coastal groundwater: the water found at present in many coastal aquifers may have been recharged during the last glacial period, when sea level was over 100m lower than present, and thus is not in equilibrium with present recharge conditions. Here we show that the geochemistry of the groundwater found in the Floridan Aquifer System in south Florida is best explained by a reorganization of groundwater flow following the sea-level rise at the end of the Last Glacial Maximum approximately 18,000 years ago. We find that the geochemistry of the fresh water found in the upper aquifers at present is consistent with recharge from meteoric water during the last glacial period. The lower aquifer, however, consists of post-sea-level-rise salt water that is most similar to that of the Straits of Florida, though with some dilution from the residual fresh water from the last glacial period circulation. We therefore suggest that during the last glacial period, the entire Floridan Aquifer System was recharged with meteoric waters. After sea level rose, the increased hydraulic head reduced the velocity of the groundwater flow. This velocity reduction trapped the fresh water in the upper aquifers and initiated saltwater circulation in the lower aquifer.

Antifreeze life cycle assessment (LCA

Directory of Open Access Journals (Sweden)

Kesić Jelena

2005-01-01

Full Text Available Antifreeze based on ethylene glycol is a commonly used commercial product The classification of ethylene glycol as a toxic material increased the disposal costs for used antifreeze and life cycle assessment became a necessity. Life Cycle Assessment (LCA considers the identification and quantification of raw materials and energy inputs and waste outputs during the whole life cycle of the analyzed product. The objectives of LCA are the evaluation of impacts on the environment and improvements of processes in order to reduce and/or eliminate waste. LCA is conducted through a mathematical model derived from mass and energy balances of all the processes included in the life cycle. In all energy processes the part of energy that can be transformed into some other kind of energy is called exergy. The concept of exergy considers the quality of different types of energy and the quality of different materials. It is also a connection between energy and mass transformations. The whole life cycle can be described by the value of the total loss of exergy. The physical meaning of this value is the loss of material and energy that can be used. The results of LCA are very useful for the analyzed products and processes and for the determined conditions under which the analysis was conducted. The results of this study indicate that recycling is the most satisfactory solution for the treatment of used antifreeze regarding material and energy consumption but the re-use of antifreeze should not be neglected as a solution.

Temporal Considerations of Carbon Sequestration in LCA

Science.gov (United States)

James Salazar; Richard Bergman

2013-01-01

Accounting for carbon sequestration in LCA illustrates the limitations of a single global warming characterization factor. Typical cradle-to-grave LCA models all emissions from end-of-life processes and then characterizes these flows by IPCC GWP (100-yr) factors. A novel method estimates climate change impact by characterizing annual emissions with the IPCC GHG forcing...

Groundwater quality in the Coastal Los Angeles Basin, California

Science.gov (United States)

Fram, Miranda S.; Belitz, Kenneth

2012-01-01

The Coastal Los Angeles Basin study unit is approximately 860 square miles and consists of the Santa Monica, Hollywood, West Coast, Central, and Orange County Coastal Plain groundwater basins (California Department of Water Resources, 2003). The basins are bounded in part by faults, including the Newport-Inglewood fault zone, and are filled with Holocene-, Pleistocene-, and Pliocene-age marine and alluvial sediments. The Central Basin and Orange County Coastal Plain are divided into a forebay zone on the northeast and a pressure zone in the center and southwest. The forebays consist of unconsolidated coarser sediment, and the pressure zones are characterized by lenses of coarser sediment divided into confined to semi-confined aquifers by lenses of finer sediments. The primary aquifer system in the study unit is defined as those parts of the aquifer system corresponding to the perforated intervals of wells listed in the California Department of Public Health (CDPH) database of public-supply wells. The majority of public-supply wells are drilled to depths of 510 to 1,145 feet, consist of solid casing from the land surface to a depth of about 300 to 510 feet, and are perforated below the solid casing. Water quality in the primary aquifer system may differ from that in the shallower and deeper parts of the aquifer systems.

Field Investigation of Stream-Aquifer Interactions: A Case Study in Coastal California

Science.gov (United States)

Pritchard-Peterson, D.; Malama, B.

2017-12-01

We report here results of a detailed investigation of the dynamic interaction between a stream and an alluvial aquifer at Swanton Pacific Ranch in the Scotts Creek watershed, Santa Cruz County, California. The aquifer is an important source of groundwater for cropland irrigation and for aquatic ecosystem support. Low summer base flows in Scotts Creek are a source of serious concern for land managers, fisheries biologists, and regulatory agencies due to the presence of federally protected steelhead trout and coho salmon. An understanding of the interaction between the stream and pumped aquifer will allow for assessment of the impacts of groundwater extraction on stream flows and is essential to establishing minimum flow requirements. This will aid in the development of sustainable riparian groundwater pumping practices that meet agricultural and ecological needs. Results of extensive direct-push sampling of the subsurface, laboratory falling-head permeameter tests and particle size analysis of aquifer sediments, multi-day pumping tests, long-term passive monitoring of aquifer hydraulic heads and stream stage and discharge, and electrical resistivity interrogation of the subsurface are reported here. Findings indicate that the permeable subsurface formation tapped by irrigation wells is a leaky semi-confined aquifer, overlain by a thin low permeability layer of silt and clay above which lies Scotts Creek. These results are particularly useful to land managers responsible for groundwater abstraction from wells that tap into the aquifer. Additionally, an index of stream-aquifer connectivity is proposed that would allow land managers to conveniently modify groundwater abstraction practices, minimizing concerns of stream depletion.

Stepped-wedge cluster-randomised controlled trial to assess the cardiovascular health effects of a managed aquifer recharge initiative to reduce drinking water salinity in southwest coastal Bangladesh: study design and rationale.

Science.gov (United States)

Naser, Abu Mohd; Unicomb, Leanne; Doza, Solaiman; Ahmed, Kazi Matin; Rahman, Mahbubur; Uddin, Mohammad Nasir; Quraishi, Shamshad B; Selim, Shahjada; Shamsudduha, Mohammad; Burgess, William; Chang, Howard H; Gribble, Matthew O; Clasen, Thomas F; Luby, Stephen P

2017-09-01

Saltwater intrusion and salinisation have contributed to drinking water scarcity in many coastal regions globally, leading to dependence on alternative sources for water supply. In southwest coastal Bangladesh, communities have few options but to drink brackish groundwater which has been associated with high blood pressure among the adult population, and pre-eclampsia and gestational hypertension among pregnant women. Managed aquifer recharge (MAR), the purposeful recharge of surface water or rainwater to aquifers to bring hydrological equilibrium, is a potential solution for salinity problem in southwest coastal Bangladesh by creating a freshwater lens within the brackish aquifer. Our study aims to evaluate whether consumption of MAR water improves human health, particularly by reducing blood pressure among communities in coastal Bangladesh. The study employs a stepped-wedge cluster-randomised controlled community trial design in 16 communities over five monthly visits. During each visit, we will collect data on participants' source of drinking and cooking water and measure the salinity level and electrical conductivity of household stored water. At each visit, we will also measure the blood pressure of participants ≥20 years of age and pregnant women and collect urine samples for urinary sodium and protein measurements. We will use generalised linear mixed models to determine the association of access to MAR water on blood pressure of the participants. The study protocol has been reviewed and approved by the Institutional Review Boards of the International Centre for Diarrheal Disease Research, Bangladesh (icddr,b). Informed written consent will be taken from all the participants. This study is funded by Wellcome Trust, UK. The study findings will be disseminated to the government partners, at research conferences and in peer-reviewed journals. NCT02746003; Pre-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the

Regional assessment of aquifers for thermal-energy storage. Volume 2: Regions 7 through 12

Science.gov (United States)

1981-06-01

The geologic and hydrologic framework, major aquifers, aquifers which are suitable and unsuitable for annual thermal energy storage (ATES) and the ATES potential of the unglaciated central region, glaciated Appalachians, unglaciated Appalachians, coastal plain, Hawaii, and Alaska are discussed.

Time series analysis for the estimation of tidal fluctuation effect on different aquifers in a small coastal area of Saijo plain, Ehime prefecture, Japan.

Science.gov (United States)

Kumar, Pankaj; Tsujimura, Maki; Nakano, Takanori; Minoru, Tokumasu

2013-04-01

Considering the current poor understanding of the seawater-freshwater (SW-FW) interaction pattern at dynamic hydro-geological boundary of coastal aquifers, this work strives to study tidal effect on groundwater quality using chemical tracers combined with environmental isotopes. In situ measurement data of electrical conductivity and groundwater level along with laboratory measurement data of hydro-chemical species were compared with tidal level data measured by Hydrographic and Oceanographic Department, Saijo City, Japan for time series analysis. Result shows that diurnal tides have significant effect on groundwater level as well as its chemical characteristics; however, the magnitude of effect is different in case of different aquifers. Various scatter diagrams were plotted in order to infer mechanisms responsible for water quality change with tidal phase, and results show that cations exchange, selective movement and local SW-FW mixing were likely to be the main processes responsible for water quality changes. It was also found that geological structure of the aquifers is the most important factor affecting the intensity of tidal effect on water quality.

Effect of transient wave forcing on the behavior of arsenic in a sandy nearshore aquifer

Science.gov (United States)

Rakhimbekova, S.; O'Carroll, D. M.; Robinson, C. E.

2016-12-01

Waves cause large quantities of coastal water to recirculate across the groundwater-coastal water interface in addition to inducing complex groundwater flows in the nearshore aquifer. Due to the distinct chemical composition of recirculating coastal water compared with discharging terrestrial groundwater, wave-induced recirculations and flows can alter geochemical gradients in the nearshore aquifer which may subsequently affect the mobilization and transport of reactive pollutants (e.g., arsenic). The impact of seasonal geochemical and hydrological variability on the occurrence and mobility of arsenic near the groundwater-surface water interface has been shown previously in riverine settings, however, the impact of high frequency geochemical variations (e.g., varying wave conditions) on arsenic mobility in groundwater-surface water environments is unclear. The objective of the study was to assess the impact of intensified wave conditions on the behavior of arsenic in a nearshore aquifer to determine the factors regulating its mobility and transport to receiving coastal waters. Field investigations were conducted at a permeable beach on the Great Lakes during a period of intensified wave conditions (wave event). High spatial resolution pore water sampling captured the geochemical conditions in the nearshore aquifer prior to the wave event, immediately after the wave event and over a recovery period of 3 weeks following the wave event. Shifts in pH and redox potential (ORP) gradients in response to varying wave conditions caused shifts in the iron and arsenic distributions in the aquifer. Sediment analysis was combined with the pore water distributions to assess the release of sediment-bound arsenic in response to the varying wave conditions. Insight into the effect of transient forcing on arsenic mobility and transport in groundwater-surface water environments is important for evaluating the potential risks associated with this toxic metalloid. The findings of this

Survey on the Use of LCA in European Chemical Industry

DEFF Research Database (Denmark)

Olsen, Stig Irving

1999-01-01

During 1997 a questionnaire was sent to 40 European chemical manufacturers representing different positions in the supply chain. 25 companies (62.5%) responded, of which 23 had been involved in LCA to some degree. The questionnaire consisted of 30 questions divided into four parts dealing...... industry has taken up the LCA methodology and is testing its applicability for their purposes, although they still feel the methodology is a bit immature. The resources devoted to LCA depends to a great extent on the company's position in the supply chain and on the size of the company. Many of the LCA...

Compaction of Aquifer at Different Depths: Observations from a Vertical GPS Array in the Coastal Center of the University of Houston, Texas

Science.gov (United States)

Lee, D.; Kearns, T.; Yang, L.; Wang, G.

2014-12-01

Houston and the surrounding Harris County have experienced the detrimental effects of subsidence even prior to World War II, to the extent that the land along Galveston Bay had sunk as much as 20 feet since 1906. One dramatic example is the Brownwood subdivision, a coastal community in Baytown where continuous flooding due to subsidence forced the area to be deemed unlivable and consequently abandoned. Thus, Houston's changes in groundwater and compaction of its aquifers are of relatively high concern to those in the public (infrastructure), private (oil & gas), and international (Port of Houston Authority) sectors. One of the key questions related to the subsidence issue in Houston area is what are the contributions of sediments at different depths, and what particularly is the contribution from shallow sediments? To address these questions, University of Houston has installed a vertical GPS array in the UH Coastal Center in March 2014. The GPS array includes four permanent GPS stations with the antenna pole foundations anchored at different depths below ground surface (-10 m, -7m, -4m, 0 m). A special, double-pipe GPS antenna monument was designed for GPS stations with the array. This project was funded by an NSF grant and a UH internal grant. Five groundwater wells with the depths ranging from 2 m to 100 m below the ground surface were also installed at the UH Coastal Center site. This study will investigate continuous GPS and groundwater level measurements (March-November, 2014) at the UHCC site. It is expected that the GPS array will provide total information on subsidence as well as compaction of aquifers within different depth ranges (0 to -4m, -4 to -7 m, -7 to -10m, and below -10 m). Correlation of land subsidence and groundwater fluctuation will also be investigated.

Making the most of LCA in technical inter-organisational R&D projects

DEFF Research Database (Denmark)

Sandin, Gustav; Clancy, Gunilla; Heimersson, Sara

2014-01-01

In technical Research and Development (R&D) projects, a Life Cycle Assessment (LCA) of the technology under development is sometimes carried out. Particularly in inter-organisational R&D projects, the roles of LCAs tend to be unclear and arbitrary, and as a consequence, LCA work is not adequately...... designed for the needs of the project. There is a need for research on how to choose an appropriate role for LCA in such projects and how to plan LCA work accordingly. We have identified some possible roles of LCA in inter-organisational R&D projects and used experiences from LCA work in different...... such projects to identify four project characteristics that are decisive for what roles the LCA can have. The project characteristics are: (i) the project's potential influence on environmental impacts, (ii) the degrees of freedom available for the technical direction of the project, (iii) the project...

Hydrodynamic characterization of the Paleocene aquifer in the ...

African Journals Online (AJOL)

user

2009-05-15

May 15, 2009 ... African Journal of Environmental Science and Technology Vol. 3 (5), pp. 141-148 ..... hydrogeological study of the coastal sedimentary basin of. Togo intended to ... isotopic study and modeling of the Paleocene aquifer in the.

The limited role of aquifer heterogeneity on metal reduction in an Atlantic coastal plain determined by push-pull tests

International Nuclear Information System (INIS)

Mailloux, Brian J.; Devlin, Stephanie; Fuller, Mark E.; Onstott, T.C.; De Flaun, Mary F.; Choi, K.-H.; Green-Blum, Maria; Swift, Donald J.P.; McCarthy, John; Dong Hailiang

2007-01-01

Sixty push-pull experiments were conducted to determine the factors controlling Fe(III) and Mn(IV) reduction in a well-characterized, shallow, coastal plain aquifer near Oyster, VA, USA. The five multi-level samplers each equipped with 12 ports sampled a heterogeneous portion of the aquifer from 4.4 to 8m-bgs. Each multi-level sampler (MLS) was injected with groundwater that contained NO 3 - and Br - along with: (1) just groundwater (control treatment), (2) humics, (3) lactate (conducted twice) and (4) lactate plus humics. Microbially mediated Fe(III) reduction caused the aqueous Fe Tot concentrations to increase at every depth in the lactate treatment with significant increases within 1 day even while NO 3 - was present. Little change in the Fe Tot concentrations were observed in the control and humics treatment. Humics may have acted as an electron shuttle to increase Fe(III) reduction in the lactate plus humics treatment. The amount of Mn(IV) reduction was significantly lower than that of Fe(III) reduction. Geochemical modeling indicated that gas formation, sorption on reactive surfaces, and mineral precipitation were important processes and that Fe(III) and SO 4 2- reduction were co-occurring. Conditions were favorable for the precipitation of Fe-carbonates, Fe-sulfides and Fe-silicates. In the lactate treatment protist concentrations increased then decreased and planktonic cell concentrations steadily increased, whereas no change was observed in the control treatment. Correlations of Fe(III) reduction with physical and chemical heterogeneity were weak, probably as a result of the abundance of Fe(III) bearing minerals relative to electron donor abundance and that the push-pull test sampled a representative elemental volume that encompassed the microbial diversity within the aquifer. This work indicates that stimulating metal reduction in aquifer systems is a feasible method for remediating heterogeneous subsurface sites contaminated with metals and

Characterization of California Central Coast Aquifers using Pneumatic Slug Tests

Science.gov (United States)

Aurelius, S.; Platt, D.; Whetsler, B.; Malama, B.

2017-12-01

The recent prolonged drought in California, where about 75% of the population depends to some extent ongroundwater, has led to increased stresses on the state's groundwater resources due to reduced recharge andincreased abstraction to supplement dwindling surface water supplies for irrigation and other urban uses.These factors have conspired to cause historic lows in groundwater levels, lost aquifer storage capacity dueincreased potential for land subsidence, and degraded water quality in coastal aquifers faced with increasedrates of seawater intrusion. Groundwater accounts for about a third of the total water uses in California,with some coastal communities being 100% dependent on groundwater. Irrigation accounts for over 60%of all state groundwater withdrawals in California. In light of this, the state of California recently passedthe Sustainable Groundwater Management Act (SGMA) aimed at bringing the State's groundwater basinsinto sustainable regimes of abstraction, recharge and storage. Groundwater ow models are critical to thesuccessful implementation of the SGMA legislation. However, the usefulness of the models is severely limitedby a lack of detailed knowledge of aquifer properties at spatial scales that allow for accurate projections tobe made about groundwater basin sustainability by resource managers. We report here the results of highresolution pneumatic slug tests performed in two shallow aquifers in San Luis Obispo County on the CaliforniaCentral Coast to obtain detailed information about aquifer properties, including permeability and storage,and their spatial variability.

Long-term pumping test to study the impact of an open-loop geothermal system on seawater intrusion in a coastal aquifer: the case study of Bari (Southern Italy)

Science.gov (United States)

Clementina Caputo, Maria; Masciale, Rita; Masciopinto, Costantino; De Carlo, Lorenzo

2016-04-01

The high cost and scarcity of fossil fuels have promoted the increased use of natural heat for a number of direct applications. Just as for fossil fuels, the exploitation of geothermal energy should consider its environmental impact and sustainability. Particular attention deserves the so-called open loop geothermal groundwater heat pump (GWHP) system, which uses groundwater as geothermal fluid. From an economic point of view, the implementation of this kind of geothermal system is particularly attractive in coastal areas, which have generally shallow aquifers. Anyway the potential problem of seawater intrusion has led to laws that restrict the use of groundwater. The scarcity of freshwater could be a major impediment for the utilization of geothermal resources. In this study a new methodology has been proposed. It was based on an experimental approach to characterize a coastal area in order to exploit the low-enthalpy geothermal resource. The coastal karst and fractured aquifer near Bari, in Southern Italy, was selected for this purpose. For the purpose of investigating the influence of an open-loop GWHP system on the seawater intrusion, a long-term pumping test was performed. The test simulated the effects of a prolonged withdrawal on the chemical-physical groundwater characteristics of the studied aquifer portion. The duration of the test was programmed in 16 days, and it was performed with a constant pumping flowrate of 50 m3/h. The extracted water was outflowed into an adjacent artificial channel, by means of a piping system. Water depth, temperature and electrical conductivity of the pumped water were monitored for 37 days, including also some days before and after the pumping duration. The monitored parameters, collected in the pumping and in five observation wells placed 160 m down-gradient with respect to the groundwater flow direction, have been used to estimate different scenarios of the impact of the GWHP system on the seawater intrusion by mean of a

Hydrogeology, water quality, and microbial assessment of a coastal alluvial aquifer in western Saudi Arabia: potential use of coastal wadi aquifers for desalination water supplies [Hydrogéologie, qualité de l’eau et évaluation microbienne d’un aquifère côtier alluvial dans l’Ouest de l’Arabie Saoudite: utilisation potentielle des aquifères côtiers des oueds pour l’alimentation en eau après désalinisation] [Hidrogeologia, qualidade da água e avaliação microbiológica de um aquífero costeiro no oeste da Arábia Saudita: uso potencial de aquíferos de wadi costeiros para dessalinização de águas destinadas a abastecimento] [Hidrogeología, calidad de agua y evaluación microbiana de un acuífero costero aluvial en Arabia Saudita occidental: uso potencial de acuíferos costeros uadis para la desalinización de los abastecimientos de agua

KAUST Repository

Missimer, Thomas M.

2014-07-20

Wadi alluvial aquifers located along coastal areas of the Middle East have been assumed to be suitable sources of feed water for seawater reverse osmosis facilities based on high productivity, connectedness to the sea for recharge, and the occurrence of seawater with chemistry similar to that in the adjacent Red Sea. An investigation of the intersection of Wadi Wasimi with the Red Sea in western Saudi Arabia has revealed that the associated predominantly unconfined alluvial aquifer divides into two sand-and-gravel aquifers at the coast, each with high productivity (transmissivity = 42,000 m2/day). This aquifer system becomes confined near the coast and contains hypersaline water. The hydrogeology of Wadi Wasimi shows that two of the assumptions are incorrect in that the aquifer is not well connected to the sea because of confinement by very low hydraulic conductivity terrigenous and marine muds and the aquifer contains hypersaline water as a result of a hydraulic connection to a coastal sabkha. A supplemental study shows that the aquifer system contains a diverse microbial community composed of predominantly of Proteobacteria with accompanying high percentages of Gammaproteobacteria, Alphaproteobacteria and Deltaproteobacteria.

The fault pattern in the northern Negev and southern Coastal Plain of Israel and its hydrogeological implications for groundwater flow in the Judea Group aquifer

Science.gov (United States)

Weinberger, G.; Rosenthal, E.

1994-03-01

On the basis of a broadly expanding data base, the hydrogeological properties of the Judea Group sequence in the northern Negev and southern Coastal Plain of Israel have been reassessed. The updated subsurface model is based on data derived from water- and oil-wells and on recent large-scale geophysical investigations. A new regional pattern of the reassessed geological through the subsurface of the study area has been revealed. In view of the reassessed geological and hydrological subsurface setting, it appears that the Judea Group aquifer should not be regarded as one continuous and undisturbed hydrological unit; owing to the occurrence of regional faults, its subaquifers are locally interconnected. These subaquifers, which contain mainly high-quality water, are juxtaposed, as a result of faulting, against Kurnub Group sandstones containing brackish paleowater. The latter Group is faulted against late Jurassic formations containing highly saline groundwater. In the Beer Sheva area, the Judea Group aquifer is vertically displaced against the Senonian and Eocene Mt. Scopus and Avdat Groups, which also contain brackish and saline water. In the southern Coastal Plain, major faults locally dissect also the Pleistocene Kurkar Group, facilitating inflow of Mg-rich groundwater deriving from Judea Group dolomites. The new geological evidence and its hydrogeological implications provide new solutions for previously unexplained salinization phenomena.

Archive of Digital Boomer and CHIRP Seismic Reflection Data Collected During USGS Field Activity 08LCA03 in Lake Panasoffkee, Florida, May 2008

Science.gov (United States)

Harrison, Arnell S.; Dadisman, Shawn V.; McBride, W. Scott; Flocks, James G.; Wiese, Dana S.

2009-01-01

In May of 2008, the U.S. Geological Survey (USGS) conducted geophysical surveys in Lake Panasoffkee, located in central Florida, as part of the USGS Lakes and Coastal Aquifers (LCA) study. This report serves as an archive of unprocessed digital boomer and Compressed High Intensity Radar Pulse (CHIRP)* seismic reflection data, trackline maps, navigation files, Field Activity Collection System (FACS) logs, Geographic Information System (GIS) files, and formal Federal Geographic Data Committee (FGDC) metadata. Filtered and gained (a relative increase in signal amplitude) digital images of the seismic profiles and geospatially corrected interactive profiles are also provided. Refer to the Acronyms page for expansions of acronyms and abbreviations used in this report. *Due to poor data acquisition conditions associated with the lake bottom sediments, only two CHIRP tracklines were collected during this field activity. The archived trace data are in standard Society of Exploration Geophysicists (SEG) SEG-Y format (Barry and others, 1975) and may be downloaded and processed with commercial or public domain software such as Seismic Unix (SU). Example SU processing scripts and USGS software for viewing the SEG-Y files (Zihlman, 1992) are provided. The USGS Florida Integrated Science Center (FISC) - St. Petersburg assigns a unique identifier to each cruise or field activity. For example, 08LCA03 tells us the data were collected in 2008 for the Lakes and Coastal Aquifers (LCA) study and the data were collected during the third field activity for that study in that calendar year. Refer to http://walrus.wr.usgs.gov/infobank/programs/html/definition/activity.html for a detailed description of the method used to assign the field activity ID. The naming convention used for each seismic line is as follows: yye##a, where 'yy' are the last two digits of the year in which the data were collected, 'e' is a 1-letter abbreviation for the equipment type (for example, b for boomer and c

Natural and anthropogenic factors affecting freshwater lenses in coastal dunes of the Adriatic coast

Science.gov (United States)

Cozzolino, Davide; Greggio, Nicolas; Antonellini, Marco; Giambastiani, Beatrice Maria Sole

2017-08-01

This study characterizes the near-shore portion of the shallow coastal aquifer included in the Ravenna area (Northern Italy) with special attention to the roles of coastal dunes as freshwater reservoirs and their buffer on groundwater salinity. The paper focuses on the presence and evolution of freshwater lenses below coastal dunes and highlights the existing differences between preserved natural dunes and dunes strongly affected by human intervention. The influence that multiple natural and anthropogenic factors, such as land cover, local drainage network, and beach erosion have on the presence, size and evolution of the freshwater lenses in the aquifer is quantified and discussed. The methodology includes multiple seasonal monitoring and sampling campaigns of physical (water level, salinity, and temperature) and chemical (major cations and anions) groundwater parameters. Results indicate that freshwater lenses, where existing, are limited in thickness (about 1-2 m). Proximity to drainage ditches as well as limited dune elevation and size do not allow the formation and permanent storage of large freshwater lenses in the aquifer below the dunes. The pine forest land cover, that replaced the typical bush or sand cover, intensifies evapotranspiration reducing net infiltration and freshwater storage. The cation species distribution in the water shows that a freshening process is ongoing in preserved natural sites with stable or advancing beaches, whereas a salinization process is ongoing in anthropogenic-impacted areas with strongly-fragmented dune systems. Currently, the thin freshwater lenses in the shallow Ravenna coastal aquifer are limited in space and have no relevance for irrigation or any other human activity. The dune-beach system, however, is the recharge zone of the coastal aquifer and its protection is important to reduce water and soil salinization, which in turn control the health of the whole coastal ecosystem.

Attributional and consequential LCA of milk production

DEFF Research Database (Denmark)

Thomassen, Marlies A; Dalgaard, Randi; Heijungs, Reinout

2008-01-01

Background, aim and scope  Different ways of performing a life cycle assessment (LCA) are used to assess the environmental burden of milk production. A strong connection exists between the choice between attributional LCA (ALCA) and consequential LCA (CLCA) and the choice of how to handle co......-products. Insight is needed in the effect of choice on results of environmental analyses of agricultural products, such as milk. The main goal of this study was to demonstrate and compare ALCA and CLCA of an average conventional milk production system in The Netherlands. Materials and methods  ALCA describes...... the pollution and resource flows within a chosen system attributed to the delivery of a specified amount of the functional unit. CLCA estimates how pollution and resource flows within a system change in response to a change in output of the functional unit. For an average Dutch conventional milk production...

Profitability Evaluation of a Hybrid Geothermal and CO2 Sequestration Project for a Coastal Hot Saline Aquifer.

Science.gov (United States)

Plaksina, Tatyana; Kanfar, Mohammed

2017-11-01

With growing interest in commercial projects involving industrial volume CO2 sequestration, a concern about proper containment and control over the gas plume becomes particularly prominent. In this study, we explore the potential of using a typical coastal geopressured hot saline aquifer for two commercial purposes. The first purpose is to harvest geothermal heat of the aquifer for electricity generation and/or direct use and the second one is to utilize the same rock volume for safe and controlled CO2 sequestration without interruption of heat production. To achieve these goals, we devised and economically evaluated a scheme that recovers operational and capital costs within first 4 years and yields positive internal rate of return of about 15% at the end of the operations. Using our strategic design of well placement and operational scheduling, we were able to achieve in our numerical simulation study the following results. First, the hot water production rates allowed to run a 30 MW organic Rankine cycle plant for 20 years. Second, during the last 10 years of operation we managed to inject into the same reservoir (volume of 0.8 x 109 m3) approximately 10 million ton of the supercritical gas. Third, decades of numerical monitoring the plume after the end of the operations showed that this large volume of CO2 is securely sequestrated inside the reservoir without compromising the caprock integrity.

LCA Experiences in Danish Industry: Results of a Survey

DEFF Research Database (Denmark)

Broberg, Ole; Christensen, Per

1999-01-01

A study on Danish industry's experiences with LCA has been performed. Twenty-six enterprises from different sectors filled in a questionnaire. The enterprises are still in an adoption and learning phase and experiences with full-blown LCA's are sparse. Expectations of future market pressure...

Water quality considerations on the rise as the use of managed aquifer recharge systems widens

NARCIS (Netherlands)

Hartog, Niels; Stuyfzand, Pieter J.

2017-01-01

Managed Aquifer Recharge (MAR) is a promising method of increasing water availability in water stressed areas by subsurface infiltration and storage, to overcome periods of drought, and to stabilize or even reverse salinization of coastal aquifers. Moreover, MAR could be a key technique in making

Involvement of LCA5 in Leber congenital amaurosis and retinitis pigmentosa in the Spanish population.

Science.gov (United States)

Corton, Marta; Avila-Fernandez, Almudena; Vallespín, Elena; López-Molina, María Isabel; Almoguera, Berta; Martín-Garrido, Esther; Tatu, Sorina D; Khan, M Imran; Blanco-Kelly, Fiona; Riveiro-Alvarez, Rosa; Brión, María; García-Sandoval, Blanca; Cremers, Frans P M; Carracedo, Angel; Ayuso, Carmen

2014-01-01

We aimed to identify novel genetic defects in the LCA5 gene underlying Leber congenital amaurosis (LCA) in the Spanish population and to describe the associated phenotype. Case series. A cohort of 217 unrelated Spanish families affected by autosomal recessive or isolated retinal dystrophy, that is, 79 families with LCA and 138 families with early-onset retinitis pigmentosa (EORP). A total of 100 healthy, unrelated Spanish individuals were screened as controls. High-resolution homozygosity mapping was performed in 44 patients with LCA using genome-wide single nucleotide polymorphism (SNP) microarrays. Direct sequencing of the LCA5 gene was performed in 5 patients who showed homozygous regions at chromosome 6 and in 173 unrelated individuals with LCA or EORP. The ophthalmic history of 8 patients carrying LCA5 mutations was reviewed and additional examinations were performed, including electroretinography (ERG), optical coherence tomography (OCT), and fundus photography. Single nucleotide polymorphism genotyping, identity-by-descent (IBD) regions, LCA5 mutations, best-corrected visual acuity, visual field assessments, fundus appearance, ERG, and OCT findings. Four novel and 2 previously reported LCA5 mutations have been identified in 6 unrelated families with LCA by homozygosity mapping or Sanger sequencing. Thus, LCA5 mutations have a frequency of 7.6% in the Spanish population. However, no LCA5 mutations were found in 138 patients with EORP. Although most of the identified LCA5 mutations led to a truncated protein, a likely pathogenic missense variant was identified for the first time as a cause of LCA, segregating in 2 families. We also have characterized a novel splicing site mutation at the RNA level, demonstrating that the mutant LCA5 transcript was absent in a patient. All patients carrying LCA5 mutations presented nystagmus, night blindness, and progressive loss of visual acuity and visual field leading to blindness toward the third decade of life. Fundoscopy

Water quality considerations on the rise as the use of managed aquifer recharge systems widens

NARCIS (Netherlands)

Hartog, Niels; Stuijfzand, Pieter

2017-01-01

Managed Aquifer Recharge (MAR) is a promising method of increasing water availability in water stressed areas by subsurface infiltration and storage, to overcome periods of drought, and to stabilize or even reverse salinization of coastal aquifers. Moreover, MAR could be a key technique in making

On process optimization considering LCA methodology.

Science.gov (United States)

Pieragostini, Carla; Mussati, Miguel C; Aguirre, Pío

2012-04-15

The goal of this work is to research the state-of-the-art in process optimization techniques and tools based on LCA, focused in the process engineering field. A collection of methods, approaches, applications, specific software packages, and insights regarding experiences and progress made in applying the LCA methodology coupled to optimization frameworks is provided, and general trends are identified. The "cradle-to-gate" concept to define the system boundaries is the most used approach in practice, instead of the "cradle-to-grave" approach. Normally, the relationship between inventory data and impact category indicators is linearly expressed by the characterization factors; then, synergic effects of the contaminants are neglected. Among the LCIA methods, the eco-indicator 99, which is based on the endpoint category and the panel method, is the most used in practice. A single environmental impact function, resulting from the aggregation of environmental impacts, is formulated as the environmental objective in most analyzed cases. SimaPro is the most used software for LCA applications in literature analyzed. The multi-objective optimization is the most used approach for dealing with this kind of problems, where the ε-constraint method for generating the Pareto set is the most applied technique. However, a renewed interest in formulating a single economic objective function in optimization frameworks can be observed, favored by the development of life cycle cost software and progress made in assessing costs of environmental externalities. Finally, a trend to deal with multi-period scenarios into integrated LCA-optimization frameworks can be distinguished providing more accurate results upon data availability. Copyright © 2011 Elsevier Ltd. All rights reserved.

Introduction to LCA Methodology

DEFF Research Database (Denmark)

Hauschild, Michael Z.

2018-01-01

In order to offer the reader an overview of the LCA methodology in the preparation of the more detailed description of its different phases, a brief introduction is given to the methodological framework according to the ISO 14040 standard and the main elements of each of its phases. Emphasis...

Reliability of groundwater supply from a coastal aquifer in the context of climate and socio-economic changes

Science.gov (United States)

Eley, Malte; Schöniger, Hans Matthias; Gelleszun, Marlene; Wolf, Jens; Schneider, Anke; Wiederhold, Helga; Meon, Günter

2017-04-01

Especially coastal areas are vulnerable in case of sea level rise and changing climate conditions. Therefore, the NAWAK study (design of sustainable adaptation strategies for infrastructures in water management under the conditions of climatic and demographic change) started in 2013. It is designed to assess impairments of groundwater availability for a coastal lowland aquifer system in North-West Germany (> 1.000 km2) in the context of climate and socio-economic changes. The research results are focused on the quantification of the groundwater availability for past and future scenarios. Impacts from both climatic and socio-economic changes on the water availability and water balance are assessed by means of hydrologic, hydrogeological and geophysical models and methods, which where developed and adapted by project partners. For the model area there are three fields of work to create the conditions for a density dependent calculation of changings in salt-freshwater budget with the numerical model d3f++ (distributed density-driven Flow). The first is the description of initial conditions in three dimensions, especially for the salt-freshwater boundary. That description is based on airborne electromagnetic data of the underground and a complex processing to identify the differences between salt and freshwater, without anthropogenic and geologic influences. A validation is possible by comparison with groundwater measurements and an online monitoring of specific conductivity. The second is the calculation and measurement of flow conditions to derive the boundary conditions and the groundwater recharge. The groundwater recharge was calculated by using the hydrologic model PANTA RHEI. It is a conceptual model with partly physic-based modules, especially for the soil water processes. The model was calibrated and validated by discharge measurements and groundwater levels. The third step is a detailed information about the spatial discretization and the reconstruction of

LCA of Drinking Water Supply

DEFF Research Database (Denmark)

Godskesen, Berit; Meron, Noa; Rygaard, Martin

2018-01-01

Water supplies around the globe are growing complex and include more intense treatment methods than just decades ago. Now, desalination of seawater and wastewater reuse for both non-potable and potable water supply have become common practice in many places. LCA has been used to assess...... the potentials and reveal hotspots among the possible technologies and scenarios for water supplies of the future. LCA studies have been used to support decisions in the planning of urban water systems and some important findings include documentation of reduced environmental impact from desalination of brackish...... water over sea water, the significant impacts from changed drinking water quality and reduced environmental burden from wastewater reuse instead of desalination. Some of the main challenges in conducting LCAs of water supply systems are their complexity and diversity, requiring very large data...

Addressing crop interactions within cropping systems in LCA

DEFF Research Database (Denmark)

Goglio, Pietro; Brankatschk, Gerhard; Knudsen, Marie Trydeman

2018-01-01

objectives of this discussion article are as follows: (i) to discuss the characteristics of cropping systems which might affect the LCA methodology, (ii) to discuss the advantages and the disadvantages of the current available methods for the life-cycle assessment of cropping systems, and (iii) to offer...... management and emissions, and (3) functional unit issues. The LCA approaches presented are as follows: cropping system, allocation approaches, crop-by-crop approach, and combined approaches. The various approaches are described together with their advantages and disadvantages, applicability...... considers cropping system issues if they are related to multiproduct and nutrient cycling, while the crop-by-crop approach is highly affected by assumptions and considers cropping system issues only if they are related to the analyzed crop. Conclusions Each LCA approach presents advantages and disadvantages...

Effects of a Reservoir Water on the GW Quality in a Coastal Aquifer of Semi-arid Region, North-east of Tunisia

Science.gov (United States)

Uchida, C.; Kawachi, A.; Tsujimura, M.; Tarhouni, J.

2015-12-01

This study investigated effects of a reservoir water in a salinized shallow aquifer based on spatial distribution of geochemical properties in groundwater (GW). In many coastal shallow aquifers of arid and semi-arid regions, groundwater table (GWT) depression and salinization have occurred due to GW overexploitation. In Korba aquifer, north-east of Tunisia, after a dam reservoir has been constructed in order to assure a water resource for irrigation, improvement of GW level and quality have been observed in the downstream area of the dam (area-A), while the GW in the other area (area-B) still has high salinity. This study, therefore, aimed to investigate the effects of the reservoir water on the GW quality. In June 2013, water quality survey and sampling were carried out at 60 wells (GW), a dam reservoir, river and the sea. Major ions, boron, bromide, and oxygen-18 and deuterium in collected samples were analyzed. From the results, in the area-B, the GWT was lower than the sea level and the high salinity were observed. The Br- concentration of the GW was correlated with the Cl- concentration, and the values of B/Cl- and Br-/Cl- of the GW were similar to the seawater. Since the GWT depression allowed the seawater to intrude into the aquifer, the GW salinization occurred in this area. On the other hand, in the area-A, GWT was higher than the seawater level, and the Na+ and Cl- concentrations were lower than the area-B. Especially, in the irrigated areas by using the reservoir water, the isotopic values, B/Cl- and Br-/Cl- of the GW were relatively higher than the others. The reservoir water has high isotopic values due to evaporation effect, and the B/Cl- and Br-/Cl- values become higher due to organic matters in sediment of the reservoir or soil in the filtration process. Thus, in addition to the direct infiltration from the reservoir into the aquifer, irrigation using a reservoir water probably has a positive impact on the GW quality in this area.

Salinization of porewater in a multiple aquitard-aquifer system in Jiangsu coastal plain, China

Science.gov (United States)

Li, Jing; Liang, Xing; Zhang, Yanian; Liu, Yan; Chen, Naijia; Abubakari, Alhassan; Jin, Menggui

2017-12-01

Chemical and isotopic compositions were analyzed in porewater squeezed from a clayey aquitard in Jiangsu coastal plain, eastern China, to interpret the salinity origin, chemical evolution and water-mass mixing process. A strong geochemical fingerprint was obtained with an aligned Cl/Br ratio of 154 in the salinized aquitard porewater over a wide Cl- concentration range (396-9,720 mg/L), indicating that porewater salinity is likely derived from a mixing with old brine with a proportion of less than 20%. Very small contributions of brine exerted limited effects on water stable isotopes. The relationships between porewater δ18O and δD indicate that shallow and intermediate porewaters could be original seawater and were subsequently diluted with modern meteoric water, whereas deep porewaters with depleted stable isotopic values were probably recharged during a cooler period and modified by evaporation and seawater infiltration. The cation-Cl relationship and mineralogy of associated strata indicate that porewater has been chemically modified by silicate weathering and ion-exchange reactions. 87Sr/86Sr ratios of 0.7094-0.7112 further confirm the input source of silicate minerals. Numerical simulations were used to evaluate the long-term salinity evolution of the deep porewater. The alternations of boundary conditions (i.e., the third aquifer mixed with brine at approximately 70 ka BP, followed by recharge of glacial meltwater at 20-25 ka BP, and then mixing with Holocene seawater at 7-10 ka BP) are responsible for the shift in porewater salinity. These timeframes correspond with the results of previous studies on ancient marine transgression-regression in Jiangsu coastal plain.

Groundwater vulnerability mapping of Qatar aquifers

Science.gov (United States)

Baalousha, Husam Musa

2016-12-01

Qatar is one of the most arid countries in the world with limited water resources. With little rainfall and no surface water, groundwater is the only natural source of fresh water in the country. Whilst the country relies mainly on desalination of seawater to secure water supply, groundwater has extensively been used for irrigation over the last three decades, which caused adverse environmental impact. Vulnerability assessment is a widely used tool for groundwater protection and land-use management. Aquifers in Qatar are carbonate with lots of fractures, depressions and cavities. Karst aquifers are generally more vulnerable to contamination than other aquifers as any anthropogenic-sourced contaminant, especially above a highly fractured zone, can infiltrate quickly into the aquifer and spread over a wide area. The vulnerability assessment method presented in this study is based on two approaches: DRASTIC and EPIK, within the framework of Geographical Information System (GIS). Results of this study show that DRASTIC vulnerability method suits Qatar hydrogeological settings more than EPIK. The produced vulnerability map using DRASTIC shows coastal and karst areas have the highest vulnerability class. The southern part of the country is located in the low vulnerability class due to occurrence of shale formation within aquifer media, which averts downward movement of contaminants.

Evaluating the human impact on groundwater quality discharging into a coastal reef lagoon

Science.gov (United States)

Rebolledo-Vieyra, M.; Hernandez-Terrones, L.; Soto, M.; Lecossec, A.; Monroy-Rios, E.

2008-12-01

The Eastern coast of the Yucatan Peninsula has the fastest growth rate in Mexico and groundwater is the only source of drinking water in the region. The consequences of the lack of proper infrastructure to collect and treat wastewater and the impact of human activities on the quality of groundwater are addressed. The groundwater in the coastal aquifer of Quintana Roo (SE Mexico) discharges directly into the ocean. In addition, the coral reef of the Eastern Yucatan Peninsula is part of the Mesoamerican Coral Reef System, one of the largest in the world. The interaction of the reef-lagoon hydraulics with the coastal aquifer of Puerto Morelos (NE Yucatan Peninsula), and a major input of NH4, SO4, SiO2, as a consequence of the use of septic tanks and the lack of modern wastewater treatment plants are presented. No seasonal parameters differences were observed, suggesting that groundwater composition reaching the reef lagoon is not changing seasonally. A conceptual model of the coastal aquifer was developed, in order to explain how the human activities are impacting directly on the groundwater quality that, potentially, will have a direct impact on the coral reef. The protection and conservation of coral reefs must be directly related with a policy of sound management of coastal aquifers and wastewater treatment.

LCA profiles for building components:

DEFF Research Database (Denmark)

Marsh, Rob

2016-01-01

. A full bivariate linear regression analysis is performed, showing statistically significant correlations with strong direct relationships between environmental impact categories. A simplified LCA profile consisting of total primary energy, global warming potential and acidification potential is developed...

Prospective time-resolved LCA of fully electric supercap vehicles in Germany.

Science.gov (United States)

Zimmermann, Benedikt M; Dura, Hanna; Baumann, Manuel J; Weil, Marcel R

2015-07-01

The ongoing transition of the German electricity supply toward a higher share of renewable and sustainable energy sources, called Energiewende in German, has led to dynamic changes in the environmental impact of electricity over the last few years. Prominent scenario studies predict that comparable dynamics will continue in the coming decades, which will further improve the environmental performance of Germany's electricity supply. Life cycle assessment (LCA) is the methodology commonly used to evaluate environmental performance. Previous LCA studies on electric vehicles have shown that the electricity supply for the vehicles' operation is responsible for the major part of their environmental impact. The core question of this study is how the prospective dynamic development of the German electricity mix will affect the impact of electric vehicles operated in Germany and how LCA can be adapted to analyze this impact in a more robust manner. The previously suggested approach of time-resolved LCA, which is located between static and dynamic LCA, is used in this study and compared with several static approaches. Furthermore, the uncertainty issue associated with scenario studies is addressed in general and in relation to time-resolved LCA. Two scenario studies relevant to policy making have been selected, but a moderate number of modifications have been necessary to adapt the data to the requirements of a life cycle inventory. A potential, fully electric vehicle powered by a supercapacitor energy storage system is used as a generic example. The results show that substantial improvements in the environmental repercussions of the electricity supply and, consequentially, of electric vehicles will be achieved between 2020 and 2031 on the basis of the energy mixes predicted in both studies. This study concludes that although scenarios might not be able to predict the future, they should nonetheless be used as data sources in prospective LCA studies, because in many cases

Hydrogeochemical characterization and groundwater quality assessment in intruded coastal brine aquifers (Laizhou Bay, China).

Science.gov (United States)

Zhang, Xiaoying; Miao, Jinjie; Hu, Bill X; Liu, Hongwei; Zhang, Hanxiong; Ma, Zhen

2017-09-01

The aquifer in the coastal area of the Laizhou Bay is affected by salinization processes related to intense groundwater exploitation for brine resource and for agriculture irrigation during the last three decades. As a result, the dynamic balances among freshwater, brine, and seawater have been disturbed and the quality of groundwater has deteriorated. To fully understand the groundwater chemical distribution and evolution in the regional aquifers, hydrogeochemical and isotopic studies have been conducted based on the water samples from 102 observation wells. Groundwater levels and salinities in four monitoring wells are as well measured to inspect the general groundwater flow and chemical patterns and seasonal variations. Chemical components such as Na + , K + , Ca 2+ , Mg 2+ , Sr 2+ , Cl - , SO 4 2- , HCO 3 - , NO 3 - , F - , and TDS during the same period are analyzed to explore geochemical evolution, water-rock interactions, sources of salt, nitrate, and fluoride pollution in fresh, brackish, saline, and brine waters. The decreased water levels without typical seasonal variation in the southeast of the study area confirm an over-exploitation of groundwater. The hydrogeochemical characteristics indicate fresh-saline-brine-saline transition pattern from inland to coast where evaporation is a vital factor to control the chemical evolution. The cation exchange processes are occurred at fresh-saline interfaces of mixtures along the hydraulic gradient. Meanwhile, isotopic data indicate that the brine in aquifers was either originated from older meteoric water with mineral dissolution and evaporation or repeatedly evaporation of retained seawater with fresher water recharge and mixing in geological time. Groundwater suitability for drinking is further evaluated according to water quality standard of China. Results reveal high risks of nitrate and fluoride contamination. The elevated nitrate concentration of 560 mg/L, which as high as 28 times of the standard content

A Combined Radio- and Stable-Isotopic Study of a California Coastal Aquifer System

Directory of Open Access Journals (Sweden)

Michael Land

2013-04-01

Full Text Available Stable and radioactive tracers were utilized in concert to characterize geochemical processes in a complex coastal groundwater system and to provide constraints on the kinetics of rock/water interactions. Groundwater samples from wells within the Dominguez Gap region of Los Angeles County, California were analyzed for a suite of major cations (Na+, K+, Mg2+, Ca2+ and anions (Cl−, SO42−, silica, alkalinity, select trace elements (Ba, B, Sr, dissolved oxygen, stable isotopes of hydrogen (δD, oxygen (δ18O, dissolved inorganic carbon (δ13CDIC, and radioactive isotopes (3H, 222Rn and 223,224,226,228Ra. In the study area, groundwater may consist of a complex mixture of native groundwater, intruded seawater, non-native injected water, and oil-field brine water. In some wells, Cl− concentrations attained seawater-like values and in conjunction with isotopically heavier δ18O values, these tracers provide information on the extent of seawater intrusion and/or mixing with oil-field brines. Groundwater 3H above 1 tritium unit (TU was observed only in a few select wells close to the Dominguez Gap area and most other well groundwater was aged pre-1952. Based on an initial 14C value for the study site of 90 percent modern carbon (pmc, groundwater age estimates likely extend beyond 20 kyr before present and confirm deep circulation of some native groundwater through multiple aquifers. Enriched values of groundwater δ13CDIC in the absence of SO42− imply enhanced anaerobic microbial methanogenesis. While secular equilibrium was observed for 234U/238U (activity ratios ~1 in host matrices, strong isotopic fractionation in these groundwater samples can be used to obtain information of adsorption/desorption kinetics. Calculated Ra residence times are short, and the associated desorption rate constant is about three orders of magnitude slower than that of the adsorption rate constant. Combined stable- and radio-isotopic results provide unique insights

A conceptual framework and monitoring strategy for movement of saltwater in the coastal plain aquifer system of Virginia

Science.gov (United States)

Mcfarland, E. Randolph

2015-09-04

A conceptual framework synthesizes previous studies to provide an understanding of conditions, processes, and relations of saltwater to groundwater withdrawal in the Virginia Coastal Plain aquifer system. A strategy for monitoring saltwater movement is based on spatial relations between the saltwater-transition zone and 612 groundwater-production wells that were regulated during 2013 by the Virginia Department of Environmental Quality. The vertical position and lateral distance and direction of the bottom of each production well’s screened interval was calculated relative to previously published groundwater chloride iso-concentration surfaces. Spatial analysis identified 81 production wells completed in the Yorktown-Eastover and Potomac aquifers that are positioned in closest proximity to the 250-milligrams-per-liter chloride surface, and from which chloride concentrations are most likely to increase above the U.S. Environmental Protection Agency’s 250-milligrams-per-liter secondary maximum-contaminant level. Observation wells are specified to distinguish vertical upconing from lateral intrusion among individual production wells. To monitor upconing, an observation well is to be collocated with each production well and completed at about the altitude of the 250-milligrams-per-liter chloride iso-concentration surface. To monitor lateral intrusion, a potential location of an observation well is projected from the bottom of each production well’s screened interval, in the lateral direction to the underlying chloride surface to a distance of 1 mile.

Profitability Evaluation of a Hybrid Geothermal and CO2 Sequestration Project for a Coastal Hot Saline Aquifer.

Directory of Open Access Journals (Sweden)

Plaksina Tatyana

2017-01-01

Full Text Available With growing interest in commercial projects involving industrial volume CO2 sequestration, a concern about proper containment and control over the gas plume becomes particularly prominent. In this study, we explore the potential of using a typical coastal geopressured hot saline aquifer for two commercial purposes. The first purpose is to harvest geothermal heat of the aquifer for electricity generation and/or direct use and the second one is to utilize the same rock volume for safe and controlled CO2 sequestration without interruption of heat production. To achieve these goals, we devised and economically evaluated a scheme that recovers operational and capital costs within first 4 years and yields positive internal rate of return of about 15% at the end of the operations. Using our strategic design of well placement and operational scheduling, we were able to achieve in our numerical simulation study the following results. First, the hot water production rates allowed to run a 30 MW organic Rankine cycle plant for 20 years. Second, during the last 10 years of operation we managed to inject into the same reservoir (volume of 0.8 x 109 m3 approximately 10 million ton of the supercritical gas. Third, decades of numerical monitoring the plume after the end of the operations showed that this large volume of CO2 is securely sequestrated inside the reservoir without compromising the caprock integrity.

Innovation strategies in a fruit growers association impacts assessment by using combined LCA and s-LCA methodologies.

Science.gov (United States)

Tecco, Nadia; Baudino, Claudio; Girgenti, Vincenzo; Peano, Cristiana

2016-10-15

In the challenging world of territorial transformations within the agriculture, there is an increasing need for an integrated methodological framework of assessment that is able to reconcile the demand for solutions that are both economically sustainable and contribute to environmental and social improvement. This study aims to assess the introduction of innovation into agro-food systems by combining an environmental life cycle (LCA) assessment and a social life cycle assessment (s-LCA) to support the decision making process of a fruit growers co-op for the adoption of mulching and covering in raspberry farming. LCA and s-LCA have been applied independently under specific consistency requirements, selecting two scenarios to compare the impact with (1) and without (2) the innovation and then combined within a cause-effect chain. The interactions between the environment and socioeconomic components were considered within a nested frameset of business and territorial features. The total emissions from raspberry production in Scenario 1, according to the Global Warming Potential (GWP) Impact Category amounted to 2.2840kg of CO2 eq. In Scenario 2, the impact of production was associated with a GWP of 0.1682kg of CO2 eq. Social repercussions analysis from Scenario 1 compared to Scenario 2 indicate more satisfaction for working conditions and the management of climate risks. The mulching and covering, implemented within a given framework of farm activity, created conditions for the preservation of a model in which raspberry production contributes to landscape protection, the business sustainability of farms and the creation of employment. The combined use of the two methods contributes to the development of a strategy planning due to its ability to deliver, as well as specific analysis at a functional level, a wider framework for assessing the consistency of the impacts related to innovation in raspberry production. Copyright © 2016 Elsevier B.V. All rights reserved.

LCA of Soil and Groundwater Remediation

DEFF Research Database (Denmark)

Søndergaard, Gitte Lemming; Owsianiak, Mikolaj

2018-01-01

Today, there is increasing interest in applying LCA to support decision-makers in contaminated site management. In this chapter, we introduce remediation technologies and associated environmental impacts, present an overview of literature findings on LCA applied to remediation technologies...... and present methodological issues to consider when conducting LCAs within the area. Within the field of contaminated site remediation , a terminology distinguishing three types of environmental impacts: primary, secondary and tertiary, is often applied. Primary impacts are the site-related impacts due...... and efficiency of remediation, which are important for assessment or primary impacts; (ii) robust assessment of primary impacts using site-specific fate and exposure models; (iii) weighting of primary and secondary (or tertiary) impacts to evaluate trade-offs between life cycle impacts from remediation...

Geohydrology and water quality of stratified-drift aquifers in the lower Merrimack and coastal river basins, southeastern New Hampshire

Science.gov (United States)

Stekl, Peter J.; Flanagan, Sarah M.

1992-01-01

Communities in the lower Merrimack River basin and coastal river basins of southeastern New Hampshire are experiencing increased demands for water because of a rapid increase in population. The population in 1987 was 225,495 and is expected to increase by 30 percent during the next decade. As of 1987, five towns used the stratified-drift aquifers for municipal supply and withdrew an estimated 6 million gallons per day. Four towns used the bedrock aquifer for municipal supply and withdrew an average of 1 .6 million gallons per day. Stratified-drift deposits cover 78 of the 327 square miles of the study area. These deposits are generally less than 10 square miles in areal extent, and their saturated thickness ranges front less than 20 feet to as much as 100 feet . Transinissivity exceeds 4,000 square feet per day in several locations. Stratified-drift aquifers in the eastern part are predominantly small ice-contact deposits surrounded by marine sediments or till of low hydraulic conductivity. Stratified-drift aquifers in the western part consist of ice-contact and proglacial deposits that are large in areal extent and are commonly in contact with surface-water bodies. Five stratified-drift aquifers, in the towns of Derry, Windham, Kingston, North Hampton, and Greenland, have the greatest potential to supply additional amounts of water. Potential yields and contributing areas of hypothetical supply wells were estimated for an aquifer in Windham near Cobbetts Pond and for an aquifer in Kingston along the Powwow River by use of a method analogous to superposition in conjunction with a numerical ground-waterflow model. The potential yield is estimated to be 0 .6 million gallons per day for the Windham-Cobbetts Pond aquifer and 4 .0 million gallons per day for the Kingston-Powwow River aquifer. Contributing recharge area for supply wells is estimated to be 1.6 square miles in the Windham-Cobbetts Pond aquifer and 4.9 square miles in the Kingston-Powwow River aquifer

Hydrogeochemistry and groundwater quality appraisal of part of south Chennai coastal aquifers, Tamil Nadu, India using WQI and fuzzy logic method

Science.gov (United States)

Krishna Kumar, S.; Bharani, R.; Magesh, N. S.; Godson, Prince S.; Chandrasekar, N.

2014-12-01

The present study was carried out to evaluate the groundwater quality and its suitability for drinking purposes in the urban coastal aquifers of part of south Chennai, Tamil Nadu, India. Twenty-three groundwater samples were collected during March 2012. The minimum and maximum values of pH (6.3-8 on scale), electrical conductivity (620-12,150 μS/cm), total dissolved solids (399.28-7,824.6 mg/l), carbonate (0-30 mg/l), bicarbonate (0.9-58.9 mg/l), chloride (70.9-4,067.89 mg/l), sulphate (17.4-105 mg/l), nitrate (0.4-6.0 mg/l), calcium (30-200 mg/l), magnesium (1.2-164 mg/l), sodium (69-1,490 mg/l) and potassium (8-340 mg/l) were recorded in the coastal aquifers of Chennai city. The groundwater samples show that the majority of the sampling points clustered on the NaCl and mixed CaMgCl facies of the piper trilinear diagram. In the Gibbs diagram, the majority of the sampling points fall under rock water and evaporation dominance field. Fuzzy membership classification suggests that the majority of the samples fall under good water type followed by excellent water and poor water categories. Groundwater quality index showing the majority of the samples falls under excellent to poor category of water. A positive correlation was observed with Cl-, SO4 2-, Ca2+, Na+, K+, EC and TDS. The extracted results of the correlation matrix and geochemical analysis suggest that the dominant ions of groundwater (Na+, Ca2+, K+, Cl- and SO4 2-) were derived from seawater intrusion and gypsum dissolution process. Nitrate concentration is most significantly derived from anthropogenic sources.

IAQ performance of interior finishing products and the role of LCA

CSIR Research Space (South Africa)

Ampofo-Anti, N

2010-01-01

Full Text Available of interior finishing products to be more performance-oriented, where performance is defined in terms of the life cycle human health effects 4 . 3.0 LCA – the science-based tool Life Cycle Assessment (LCA) is a science-based tool which is designed... of interior finishing products and the role of LCA Naalamkai Ampofo-Anti, Senior Researcher, CSIR 1.0 Introduction The environmental rating and certification of products is a voluntary, market-based response by industry and business to the consumer’s...

Globalisation and Mainstreaming of LCA

DEFF Research Database (Denmark)

Wangel, Arne

2018-01-01

The chapter describes how a globalised economy exacerbates the need of a mainstreaming of LCA, in particular the emergence of long, complex and geographically highly dispersed global value chains (GVCs). In documenting the three phases of the UNEP-SETAC Life Cycle Initiative, a conventional roadmap...

Differences of Longitudinal Chromatic Aberration (LCA) between Eyes with Intraocular Lenses from Different Manufacturers

Science.gov (United States)

Nakajima, Masashi; Hiraoka, Takahiro; Yamamoto, Toshiya; Takagi, Seiu; Hirohara, Yoko; Oshika, Tetsuro

2016-01-01

Several researchers have studied the longitudinal chromatic aberration (LCA) of eyes implanted with an intraocular lens (IOL). We investigated the LCA of eyes implanted with yellow-colored IOLs from three different manufacturers: Alcon Inc., HOYA Corp., and AMO Inc. The number of subjects was 11, 16, and 16, respectively. The LCA of eyes implanted with SN60WF and SN60AT (Alcon Inc.), and with XY-1 (HOYA Corp.), was the same as that of phakic eyes. The LCA of eyes with ZCB00V (AMO Inc.) was smaller than that of phakic eyes. The LCA of eyes implanted with Alcon’s and HOYA’s IOLs, but not the LCA of eyes implanted with AMO’s IOLs, was positively correlated with the powers of the IOLs. We also performed simulations to verify the impacts of LCA on visual performance for 4-mm pupil diameter; the simulations were a polychromatic modulation transfer function (MTF) and a visual Strehl ratio computed on the basis of an optical transfer function (VSOTF). We concluded that the differences between the LCA of different manufacturers do not affect visual performances when some extent of higher-order aberration (HOA) exists. The smaller HOA of AMO IOLs may enhance visual performance. PMID:27258141

Tracing groundwater salinization processes in coastal aquifers: a hydrogeochemical and isotopic approach in the Na-Cl brackish waters of northwestern Sardinia, Italy

Directory of Open Access Journals (Sweden)

G. Mongelli

2013-07-01

Full Text Available Throughout the Mediterranean, salinization threatens water quality, especially in coastal areas. This salinization is the result of concomitant processes related to both seawater intrusion and water–rock interaction, which in some cases are virtually indistinguishable. In the Nurra region of northwestern Sardinia, recent salinization related to marine water intrusion has been caused by aquifer exploitation. However, the geology of this region records a long history from the Palaeozoic to the Quaternary, and is structurally complex and comprises a wide variety of lithologies, including Triassic evaporites. Determining the origin of the saline component of the Jurassic and Triassic aquifers in the Nurra region may provide a useful and more general model for salinization processes in the Mediterranean area, where the occurrence of evaporitic rocks in coastal aquifers is a common feature. In addition, due to intensive human activity and recent climatic change, the Nurra has become vulnerable to desertification and, in common with other Mediterranean islands, surface water resources periodically suffer from severe shortages. With this in mind, we report new data regarding brackish and surface waters (outcrop and lake samples of the Na-Cl type from the Nurra region, including major ions and selected trace elements (B, Br, I, and Sr, in addition to isotopic data including δ18O, δD in water, and δ34S and δ18O in dissolved SO4. To identify the origin of the salinity more precisely, we also analysed the mineralogical and isotopic composition of Triassic evaporites. The brackish waters have Cl contents of up to 2025 mg L−1 , and the ratios between dissolved ions and Cl, with the exception of the Br / Cl ratio, are not those expected on the basis of simple mixing between rainwater and seawater. The δ18O and δD data indicate that most of the waters fall between the regional meteoric water line and the global meteoric water line, supporting the

Tracing groundwater salinization processes in coastal aquifers: a hydrogeochemical and isotopic approach in the Na-Cl brackish waters of northwestern Sardinia, Italy

Science.gov (United States)

Mongelli, G.; Monni, S.; Oggiano, G.; Paternoster, M.; Sinisi, R.

2013-07-01

Throughout the Mediterranean, salinization threatens water quality, especially in coastal areas. This salinization is the result of concomitant processes related to both seawater intrusion and water-rock interaction, which in some cases are virtually indistinguishable. In the Nurra region of northwestern Sardinia, recent salinization related to marine water intrusion has been caused by aquifer exploitation. However, the geology of this region records a long history from the Palaeozoic to the Quaternary, and is structurally complex and comprises a wide variety of lithologies, including Triassic evaporites. Determining the origin of the saline component of the Jurassic and Triassic aquifers in the Nurra region may provide a useful and more general model for salinization processes in the Mediterranean area, where the occurrence of evaporitic rocks in coastal aquifers is a common feature. In addition, due to intensive human activity and recent climatic change, the Nurra has become vulnerable to desertification and, in common with other Mediterranean islands, surface water resources periodically suffer from severe shortages. With this in mind, we report new data regarding brackish and surface waters (outcrop and lake samples) of the Na-Cl type from the Nurra region, including major ions and selected trace elements (B, Br, I, and Sr), in addition to isotopic data including δ18O, δD in water, and δ34S and δ18O in dissolved SO4. To identify the origin of the salinity more precisely, we also analysed the mineralogical and isotopic composition of Triassic evaporites. The brackish waters have Cl contents of up to 2025 mg L-1 , and the ratios between dissolved ions and Cl, with the exception of the Br / Cl ratio, are not those expected on the basis of simple mixing between rainwater and seawater. The δ18O and δD data indicate that most of the waters fall between the regional meteoric water line and the global meteoric water line, supporting the conclusion that they are

Monitoring and modeling infiltration–recharge dynamics of managed aquifer recharge with desalinated seawater

OpenAIRE

Ganot, Y.; Ganot, Y.; Holtzman, R.; Weisbrod, N.; Nitzan, I.; Katz, Y.; Kurtzman, D.

2017-01-01

We study the relation between surface infiltration and groundwater recharge during managed aquifer recharge (MAR) with desalinated seawater in an infiltration pond, at the Menashe site that overlies the northern part of the Israeli Coastal Aquifer. We monitor infiltration dynamics at multiple scales (up to the scale of the entire pond) by measuring the ponding depth, sediment water content and groundwater levels, using pressure sensors, single-ring infiltrometers, soil senso...

The importance of the application context for the design of Social LCA methodology

DEFF Research Database (Denmark)

Jørgensen, Andreas

comprises users of the Social LCA, their target audience, ethical considerations of relevance to the application of Social LCA, and legal limitations. The users of the Social LCA are either companies, NGOs or GOs, and the target audience is the recipients of the assessment results from the above mentioned...... user groups. Both users’ and their target audience’s views are found through analysis of interviews with potential user groups. Ethical considerations concern negative social impacts that may occur in relation to the application of Social LCA. These are included here, as it is assumed that the overall...

Alpha-emitting isotopes and chromium in a coastal California aquifer

Science.gov (United States)

Densmore, Jill N.; Izbicki, John A.; Murtaugh, Joseph M.; Swarzenski, Peter W.; Bullen, Thomas D.

2014-01-01

The unadjusted 72-h gross alpha activities in water from two wells completed in marine and alluvial deposits in a coastal southern California aquifer 40 km north of San Diego were 15 and 25 picoCuries per liter (pCi/L). Although activities were below the Maximum Contaminant Level (MCL) of 15 pCi/L, when adjusted for uranium activity; there is concern that new wells in the area may exceed MCLs, or that future regulations may limit water use from the wells. Coupled well-bore flow and depth-dependent water-quality data collected from the wells in 2011 (with analyses for isotopes within the uranium, actinium, and thorium decay-chains) show gross alpha activity in marine deposits is associated with decay of naturally-occurring 238U and its daughter 234U. Radon activities in marine deposits were as high as 2230 pCi/L. In contrast, gross alpha activities in overlying alluvium within the Piedra de Lumbre watershed, eroded from the nearby San Onofre Hills, were associated with decay of 232Th, including its daughter 224Ra. Radon activities in alluvium from Piedra de Lumbre of 450 pCi/L were lower than in marine deposits. Chromium VI concentrations in marine deposits were less than the California MCL of 10 μg/L (effective July 1, 2014) but δ53Cr compositions were near zero and within reported ranges for anthropogenic chromium. Alluvial deposits from the nearby Las Flores watershed, which drains a larger area having diverse geology, has low alpha activities and chromium as a result of geologic and geochemical conditions and may be more promising for future water-supply development.

Water quality decline in coastal aquifers under anthropic pressure: the case of a suburban area of Dakar (Senegal).

Science.gov (United States)

Re, Viviana; Cissé Faye, Seynabou; Faye, Abdoulaye; Faye, Serigne; Gaye, Cheikh Becaye; Sacchi, Elisa; Zuppi, Gian Maria

2011-01-01

In recent years, the unregulated increase of the population in coastal areas of developing countries has become source of concern for both water supply and quality control. In the region of Dakar (Senegal), approximately 80% of water resources come from groundwater reservoirs, which are increasingly affected by anthropogenic pressures. The identification of the main sources of pollution, and thus the aquifer vulnerability, is essential to provide a sound basis for the implementation of long-term geochemically based water management plans in this sub-Saharan area. With this aim, a hydrochemical and isotopic survey on 26 wells was performed in the so-called Peninsula of Cap-Vert. Results show that seawater intrusion represents the main process affecting groundwater chemical characteristics. Nitrates often exceed the World Health Organization drinking water limits: stable isotopes of dissolved nitrate (δ¹⁵N and δ¹⁸O) indicate urban sewage and fertilizers as a major source of contamination. Results depict a complex situation in which groundwater is affected by direct and indirect infiltration of effluents, mixing with seawater and freshening processes from below. Besides the relevance of the investigation at a regional level, it represents a basis for decision-making processes in an integrated water resources management and in the planning of similar monitoring strategies for other urban coastal regions.

Tracing groundwater salinization processes in coastal aquifers: a hydrogeochemical and isotopic approach in Na-Cl brackish waters of north-western Sardinia, Italy

Science.gov (United States)

Mongelli, G.; Monni, S.; Oggiano, G.; Paternoster, M.; Sinisi, R.

2013-01-01

In the Mediterranean area the demand of good quality water is often threatened by salinization, especially in coastal areas. The salinization is the result of concomitant processes due to both marine water intrusion and rock-water interaction, which in some cases are hardly distinguishable. In northwestern Sardinia, in the Nurra area, salinization due to marine water intrusion has been recently evidenced as consequence of bore hole exploitation. However, the geology of the Nurra records a long history from Paleozoic to Quaternary, resulting in relative structural complexity and in a wide variety of lithologies, including Triassic evaporites. To elucidate the origin of the saline component in the Nurra aquifer, may furnish a useful and more general model for the salinization processes in the Mediterranean area, where the occurrence of evaporitic rocks in coastal aquifers is a common feature. In addition, due to intensive human activities and recent climatic changes, the Nurra has become vulnerable to desertification and, similarly to other Mediterranean islands, surface-water resources can periodically suffer from drastic shortage. With this in mind we report new data, regarding brackish waters of Na-Cl type of the Nurra, including major ions and selected trace elements (B, Br, I and Sr) and isotopic data, including δ18O, δD in water, and δ34S and δ18O in dissolved sulphate. To better depict the origin of the salinity we also analyzed a set of Nurra Triassic evaporites for mineralogical and isotopic composition. The brackish waters have Cl contents up to 2025 mg L-1 and the ratios between dissolved ions and chlorine, with the exception of the Br/Cl ratio, are not those expected on the basis of a simple mixing between rain water and seawater. The δ18O and δD data indicate that most of the waters are within the Regional Meteoric Water Line and the Global Meteoric Water Line supporting the idea that they are meteoric in origin. A relevant consequence of the

LCA of Biofuels and Biomaterials

DEFF Research Database (Denmark)

Hjuler, Susanne Vedel; Hansen, Sune Balle

2018-01-01

, the potential of bio-products as substitutes for fossil-based products is receiving much attention. According to many LCA studies, bio-products are environmentally superior to fossil products in some life cycle impact categories, while the picture is often opposite in others. Bio-products is a highly diverse...

Origin and residence time of water in the Lima Aquifer

OpenAIRE

Montoya, Modesto; Mamani, Enoc

2014-01-01

The 8 million inhabitants of the coastal city Lima are supplied with water from the Rimac and Chillon rivers and water wells in the Lima aquifer. The history of the Rimac River flow and static level of water in its wells have been correlated to calculate the residence time of water in the aquifer it is recharged by the Rimac River until it reaches a well located 12 km away in the Miraflores District near the sea. The relative abundance of H-2 and O-18 are used to identify the origins of the w...

Hidrogeoquímica en el acuífero costero del eje bananero de Urabá Hydrogeochemistry in the coastal aquifer of the Uraba region

Directory of Open Access Journals (Sweden)

Vanesa Paredes Zúñiga

2010-07-01

Full Text Available Las técnicas hidrogeoquímicas constituyen una herramienta complementaria a la hidrogeología dado que permiten responder los interrogantes que se presentan en sistemas complejos, como es el caso de los acuíferos costeros, donde la salinidad normalmente asociada a procesos de intrusión salina puede obedecer también a la conjunción con otros aspectos hidroclimatológicos e hidrodinámicos. Con la aplicación de la hidrogeoquímica y las relaciones iónicasse evidencia que los procesos de salinización presentes en el acuífero costero del Eje Bananero de Urabá podrían estar ligados a la interacción agua-roca, a mezclas con aguas que se salinizaron como resultado de procesos de transgresión-regresión antiguos en la zona de estudio. Este artículo resume los resultados del proyecto de investigación y la aplicación de la hidrogeoquímica y relaciones iónicas como metodología válida para determinar los diferentes procesos de salinización de las aguas de las zonas litorales.Hydrogeochemical techniques provide a complementary tool to hydrogeology as they provide certainty as to the questions related to complex systems, as is the case of coastal aquifers, in which salinity, usually associated to saline intrusion processes, may result from the fusion with other hydroclimatologic and hydrodynamic aspects. With the application of hydrogeochemistry and ionic relations, it has been evidenced that salinization processes in the coastal aquifer of Urabá Banana Axis could be linked to water-rock interaction, to mixtures with waters which salinized as a result of old transgression-regression processes in the zone under study. This article summarizes the results of the research project, the application of hydrogeochemistry, and ionic relations as a valid methodology to determine the different salinization processes of coastal areas.

Monitoring and Management of Karstic Coastal Groundwater in a Changing Environment (Southern Italy: A Review of a Regional Experience

Directory of Open Access Journals (Sweden)

Maurizio Polemio

2016-04-01

Full Text Available The population concentration in coastal areas and the increase of groundwater discharge in combination with the peculiarities of karstic coastal aquifers constitute a huge worldwide problem, which is particularly relevant for coastal aquifers of the Mediterranean basin. This paper offers a review of scientific activities realized to pursue the optimal utilization of Apulian coastal groundwater. Apulia, with a coastline extending for over 800 km, is the Italian region with the largest coastal karst aquifers. Apulian aquifers have suffered both in terms of water quality and quantity. Some regional regulations were implemented from the 1970s with the purpose of controlling the number of wells, well locations, and well discharge. The practical effects of these management criteria, the temporal and spatial trend of recharge, groundwater quality, and seawater intrusion effects are discussed based on long-term monitoring. The efficacy of existing management tools and the development of predictive scenarios to identify the best way to reconcile irrigation and demands for high-quality drinking water have been pursued in a selected area. The Salento peninsula was selected as the Apulian aquifer portion exposed to the highest risk of quality degradation due to seawater intrusion. The capability of large-scale numerical models in groundwater management was tested, particularly for achieving forecast scenarios to evaluate the impacts of climate change on groundwater resources. The results show qualitative and quantitative groundwater trends from 1930 to 2060 and emphasize the substantial decrease of the piezometric level and a serious worsening of groundwater salinization due to seawater intrusion.

Understanding the LCA and ISO water footprint: A response to ...

Science.gov (United States)

Water footprinting has emerged as an important approach to assess water use related effects from consumption of goods and services. Assessment methods are proposed by two different communities, the Water Footprint Network (WFN) and the Life Cycle Assessment (LCA) community. The proposed methods are broadly similar and encompass both the computation of water use and its impacts, but differ in communication of a water footprint result. In this paper, we explain the role and goal of LCA and ISO-compatible water footprinting and resolve the six issues raised by Hoekstra (2016) in “A critique on the water-scarcity weighted water footprint in LCA”. By clarifying the concerns, we identify both the overlapping goals in the WFN and LCA water footprint assessments and discrepancies between them. The main differing perspective between the WFN and LCA-based approach seems to relate to the fact that LCA aims to account for environmental impacts, while the WFN aims to account for water productivity of global fresh water as a limited resource. We conclude that there is potential to use synergies in research for the two approaches and highlight the need for proper declaration of the methods applied. This paper advances efforts to understand ways to accurately capture use of water in life cycle analysis in other contexts. As the paper indicates, there is a discussion about whether quantities of water should be weighted by some local stress factor. This paper attempts to brid

An integrated study of spatial multicriteria analysis and mathematical modelling for managed aquifer recharge site suitability mapping and site ranking at Northern Gaza coastal aquifer.

Science.gov (United States)

Rahman, Mohammad Azizur; Rusteberg, Bernd; Uddin, Mohammad Salah; Lutz, Annegret; Saada, Muath Abu; Sauter, Martin

2013-07-30

This paper describes an integrated approach of site suitability mapping and ranking of the most suitable sites, for the implementation of Managed Aquifer Recharge (MAR) projects, using spatial multicriteria decision analysis (SMCDA) techniques and mathematical modelling. The SMCDA procedure contains constraint mapping, site suitability analysis with criteria standardization and weighting, criteria overlay by analytical hierarchy process (AHP) combined with weighted linear combination (WLC) and ordered weighted averaging (OWA), and sensitivity analysis. The hydrogeological impacts of the selected most suitable sites were quantified by using groundwater flow and transport modelling techniques. Finally, ranking of the selected sites was done with the WLC method. The integrated approach is demonstrated by a case study in the coastal aquifer of North Gaza. Constraint mapping shows that 50% of the total study area is suitable for MAR implementation. About 25% of the total area is "very good" and 25% percent is "good" for MAR, according to the site suitability analysis. Six locations were selected and ranked against six representative decision criteria. Long term (year 2003 to year 2040) groundwater flow and transport simulations were performed to quantify the selected criteria under MAR project operation conditions at the selected sites. Finally, the suitability mapping and hydrogeological investigation recommends that the location of the existing infiltration ponds, constructed near the planned North Gaza Wastewater Treatment Plant (NGWWTP) is most suitable for MAR project implementation. This paper concludes that mathematical modelling should be combined with the SMCDA technique in order to select the best location for MAR project implementation. Besides MAR project implementation, the generalised approach can be applicable for any other water resources development project that deals with site selection and implementation. Copyright © 2013 Elsevier Ltd. All rights

Monitoring and modeling infiltration-recharge dynamics of managed aquifer recharge with desalinated seawater

OpenAIRE

Ganot, Yonatan; Holtzman, Ran; Weisbrod, Noam; Nitzan, Ido; Katz, Yoram; Kurtzman, Daniel

2016-01-01

We study the relation between surface infiltration and groundwater recharge during managed aquifer recharge (MAR) with desalinated seawater in an infiltration pond, at the Menashe site that overlies the northern part of the Israeli Coastal Aquifer. We monitor infiltration dynamics at multiple scales (up to the scale of the entire pond) by measuring the ponding depth, sediment water content and groundwater levels, using pressure sensors, single-ring infiltrometers, soil sensors and observation...

LCA of a washing machine

DEFF Research Database (Denmark)

Erichsen, Hanne K. Linnet

1997-01-01

Task 2.1 has the aim to generate inforamtion of the present situation for electrical motors through life cycle assessment (LCA). When assessing the environmental burdens through out the life cycle of the motor it is necessary to look at the life cycle of the product in which the motor is used...

High-resolution hydro- and geo-stratigraphy at Atlantic Coastal Plain drillhole CR-622 (Strat 8)

Science.gov (United States)

Wrege, B.M.; Isely, J.J.

2009-01-01

We interpret borehole geophysical logs in conjunction with lithology developed from continuous core to produce high-resolution hydro- and geo-stratigraphic profiles for the drillhole CR-622 (Strat 8) in the Atlantic Coastal Plain of North Carolina. The resulting hydrologic and stratigraphic columns show a generalized relation between hydrologic and geologic units. Fresh-water aquifers encountered are the surficial, Yorktown, Pungo River and Castle Hayne. Geologic units present are of the middle and upper Tertiary and Quaternary periods, these are the Castle Hayne (Eocene), Pungo River (Miocene), Yorktown (Pliocene), James City and Flanner Beach (Pleistocene), and the topsoil (Holocene). The River Bend Formation (Oligocene) is missing as a distinct unit between the Pungo River Formation and the Castle Hayne Formation. The confining unit underlying the Yorktown Aquifer corresponds to the Yorktown Geologic Unit. The remaining hydrologic units and geologic units are hydrologically transitional and non-coincident. The lower Pungo River Formation serves as the confining unit for the Castle Hayne Aquifer, rather than the River Bend Aquifer, and separates the Pungo River Aquifer from the upper Castle Hayne Aquifer. All geologic formations were bound by unconformities. All aquifers were confined by the anticipated hydrologic units. We conclude that CR-622 (Strat 8) represents a normal sequence in the Atlantic Coastal Plain.

2d-LCA - an alternative to x-wires

Science.gov (United States)

Puczylowski, Jaroslaw; Hölling, Michael; Peinke, Joachim

2014-11-01

The 2d-Laser Cantilever Anemometer (2d-LCA) is an innovative sensor for two-dimensional velocity measurements in fluids. It uses a micostructured cantilever made of silicon and SU-8 as a sensing element and is capable of performing mesurements with extremly high temporal resolutions up to 150 kHz. The size of the cantilever defines its spatial resolution, which is in the order of 150 μm only. Another big feature is a large angular range of 180° in total. The 2d-LCA has been developed as an alternative measurement method to x-wires with the motivation to create a sensor that can operate in areas where the use of hot-wire anemometry is difficult. These areas include measurements in liquids and in near-wall or particle-laden flows. Unlike hot-wires, the resolution power of the 2d-LCA does not decrease with increasing flow velocity, making it particularly suitable for measurements in high speed flows. Comparative measurements with the 2d-LCA and hot-wires have been carried out in order to assess the performance of the new anemometer. The data of both measurement techniques were analyzed using the same stochastic methods including a spectral analysis as well as an inspection of increment statistics and structure functions. Furthermore, key parameters, such as mean values of both velocity components, angles of attack and the characteristic length scales were determined from both data sets. The analysis reveals a great agreement between both anemometers and thus confirms the new approach.

Regional Hydrogeochemistry of a Modern Coastal Mixing Zone

Science.gov (United States)

Wicks, Carol M.; Herman, Janet S.

1996-02-01

In west central Florida, groundwater samples were collected along flow paths in the unconfined upper Floridan aquifer that cross the inland, freshwater recharge area and the coastal discharge area. A groundwater flow and solute transport model was used to evaluate groundwater flow and mixing of fresh and saline groundwater along a cross section of the unconfined upper Floridan aquifer. Results show that between 8% and 15% of the fresh and 30-31% of the saline groundwater penetrates to the depth in the flow system where contact with and dissolution of gypsum is likely. The deeply circulating fresh and saline groundwater returns to the near-surface environment discharging CaSO4-rich water to the coastal area where it mixes with fresh CaHCO3 groundwater, resulting in a prediction of calcite precipitation in the modern mixing zone.

Joint Calibration of Submarine Groundwater Discharge (SGD) with Tidal Pumping: Modeling Variable-density Groundwater Flow in Unconfined Coastal Aquifer of Apalachee Bay, Gulf of Mexico

Science.gov (United States)

Li, X.; Hu, B.; Burnett, W.; Santos, I.

2008-05-01

Submarine Groundwater Discharge (SGD) as an unseen phenomenon is now recognized as an important pathway between land and sea. These discharges typically display significant spatial and temporal variability making quantification difficult. Groundwater seepage is patchy, diffuse, and temporally variable, and thus makes the estimation of its magnitude and components is a challenging enterprise. A two-dimensional hydrogeological model is developed to the near-shore environment of an unconfined aquifer at a Florida coastal area in the northeastern Gulf of Mexico. Intense geological survey and slug tests are set to investigate the heterogeneity of this layered aquifer. By applying SEAWAT2000, considering the uncertainties caused by changes of boundary conditions, a series of variable-density-flow models incorporates the tidal-influenced seawater recirculation and the freshwater-saltwater mixing zone under the dynamics of tidal pattern, tidal amplitude and variation of water table. These are thought as the contributing factors of tidal pumping and hydraulic gradient which are the driven forces of SGD. A tidal-influenced mixing zone in the near-shore aquifer shows the importance of tidal mechanism to flow and salt transport in the process of submarine pore water exchange. Freshwater ratio in SGD is also analyzed through the comparison of Submarine Groundwater Recharge and freshwater inflow. The joint calibration with other methods (natural tracer model and seepage meter) is also discussed.

LIFE CYCLE ASSESSMENT (LCA AS A TOOL FOR BUSINESS STRATEGY

Directory of Open Access Journals (Sweden)

Rodrigo Salvador

2014-09-01

Full Text Available The growing concern about the development of sustainable production systems leads organizations to seek the support of management tools for decision-making. Considering the whole life cycle of the product, the Life Cycle Assessment (LCA has an important role in this scenario. The objective of this paper is to present, through the theoretical discussion, the role of LCA in strategic planning of the organization. It showed the enormous potential for decision making on the environmental aspect, but also the critical factor in the development shares in the competitive context. The use of LCA can reduce the environmental impacts of the system under study (primary purpose and guide the range of advantages in the fields of marketing, legislation and environmental labeling, competitive strategies, efficiency use of resources and others.

Characterisation of social impacts in LCA. Part 1: Development of indicators for labour rights

DEFF Research Database (Denmark)

Dreyer, Louise Camilla; Hauschild, Michael Zwicky; Schierbeck, Jens

2010-01-01

dignity and well-being as the ultimate goal and area of protection of Social LCA. The intended main application of this framework for Social LCA was to support management decisions in companies who wish to conduct business in a socially responsible manner, by providing information about the potential...... social impacts on people caused by the activities in the life cycle of a product. Environmental LCA normally uses quantitative and comparable indicators to provide a simple representation of the environmental impacts from the product lifecycle. This poses a challenge to the Social LCA framework because......Background, Aim and Scope The authors have earlier suggested a framework for life cycle impact assessment (LCIA) to form the modelling basis of Social LCA. In this framework the fundamental labour rights were pointed out as obligatory issues to be addressed, and protection and promotion of human...

LCA sensitivity analysis of a multi-megawatt wind turbine

International Nuclear Information System (INIS)

Martinez, E.; Jimenez, E.; Blanco, J.; Sanz, F.

2010-01-01

During recent years renewables have been acquiring gradually a significant importance in the world market (especially in the Spanish energetic market) and in society; this fact makes clear the need to increase and improve knowledge of these power sources. Starting from the results of a Life Cycle Assessment (LCA) of a multi-megawatt wind turbine, this work is aimed to assess the relevance of different choices that have been made during its development. Looking always to cover the largest possible spectrum of options, four scenarios have been analysed, focused on four main phases of lifecycle: maintenance, manufacturing, dismantling, and recycling. These scenarios facilitate to assess the degree of uncertainty of the developed LCA due to choices made, excluding from the assessment the uncertainty due to the inaccuracy and the simplification of the environmental models used or spatial and temporal variability in different parameters. The work has been developed at all times using the of Eco-indicator99 LCA method. (author)

LCA sensitivity analysis of a multi-megawatt wind turbine

Energy Technology Data Exchange (ETDEWEB)

Martinez, E. [Grupo Eolicas Riojanas, Carretera de Laguardia, 91-93, 26006 Logrono, La Rioja (Spain); Department of Mechanical Engineering, University of La Rioja, Logrono, La Rioja (Spain); Jimenez, E. [Department of Electrical Engineering, University of La Rioja, Logrono, La Rioja (Spain); Blanco, J.; Sanz, F. [Department of Mechanical Engineering, University of La Rioja, Logrono, La Rioja (Spain)

2010-07-15

During recent years renewables have been acquiring gradually a significant importance in the world market (especially in the Spanish energetic market) and in society; this fact makes clear the need to increase and improve knowledge of these power sources. Starting from the results of a Life Cycle Assessment (LCA) of a multi-megawatt wind turbine, this work is aimed to assess the relevance of different choices that have been made during its development. Looking always to cover the largest possible spectrum of options, four scenarios have been analysed, focused on four main phases of lifecycle: maintenance, manufacturing, dismantling, and recycling. These scenarios facilitate to assess the degree of uncertainty of the developed LCA due to choices made, excluding from the assessment the uncertainty due to the inaccuracy and the simplification of the environmental models used or spatial and temporal variability in different parameters. The work has been developed at all times using the of Eco-indicator99 LCA method. (author)

Evaluation of the Impact of Groundwater Pumping on Freshwater-Saltwater Interface Fluctuations in a Coastal Aquifer of South Korea

Science.gov (United States)

Yoon, H.; Kim, Y.; Lee, S. H.; Ha, K.

2017-12-01

It is necessary to monitor the variation of freshwater-saltwater interface for the sustainable use of groundwater resources in coastal areas. In the present study, we developed a device to measure the location of the freshwater-saltwater interface based on the concept of the neutral buoyancy and installed it in a coastal aquifer of the western sea, South Korea. To evaluate the impact of pumping on the groundwater and saltwater-freshwater interface level, we designed nine different pumping scenarios and monitored the groundwater and saltwater-freshwater interface levels of pumping well and two observation wells. The result of monitoring groundwater level shows that the response of observation wells to the pumping is relatively fast and high, however, the response of freshwater-saltwater interface occurred when the pumping rate and duration are over 25m3/day and 48hours, respectively. For the prediction and simulation of the groundwater level fluctuation under groundwater pumping events, we designed a artificial neural network based time series model considering rainfall, tide, and pumping rate as input components. The result of the prediction shows that the correlation coefficient between observed and estimated groundwater levels is as high as 0.7. It is expected that the result of this research can provide useful information for the effective management of groundwater resources in the study area.

Using radon-222 to study coastal groundwater/surface-water interaction in the Crau coastal aquifer (southeastern France)

Science.gov (United States)

Mayer, Adriano; Nguyen, Bach Thao; Banton, Olivier

2016-11-01

Radon has been used to determine groundwater velocity and groundwater discharge into wetlands at the southern downstream boundary of the Crau aquifer, southeastern France. This aquifer constitutes an important high-quality freshwater resource exploited for agriculture, industry and human consumption. An increase in salinity occurs close to the sea, highlighting the need to investigate the water balance and groundwater behavior. Darcy velocity was estimated using radon activities in well waters according to the Hamada "single-well method" (involving comparison with radon in groundwater in the aquifer itself). Measurements done at three depths (7, 15 and 21 m) provided velocity ranging from a few mm/day to more than 20 cm/day, with highest velocities observed at the 15-m depth. Resulting hydraulic conductivities agree with the known geology. Waters showing high radon activity and high salinity were found near the presumed shoreline at 3,000 years BP, highlighting the presence of ancient saltwater. Radon activity has also been measured in canals, rivers and ponds, to trace groundwater discharges and evaluate water balance. A model of the radon spatial evolution explains the observed radon activities. Groundwater discharge to surface water is low in pond waters (4 % of total inputs) but significant in canals (55 l/m2/day).

Modeling the Effects of Storm Surge from Hurricane Jeanne on Saltwater Intrusion into the Surficial Aquifer, East-Central Florida (USA)

Science.gov (United States)

Xiao, H.; Wang, D.; Hagen, S. C.; Medeiros, S. C.; Hall, C. R.

2017-12-01

Saltwater intrusion (SWI) that has been widely recognized as a detrimental issue causing the deterioration of coastal aquifer water quality and degradation of coastal ecosystems. While it is widely recognized that SWI is exacerbated worldwide due to global sea-level rise, we show that increased SWI from tropical cyclones under climate change is also a concern. In the Cape Canaveral Barrier Island Complex (CCBIC) located in east-central Florida, the salinity level of the surficial aquifer is of great importance to maintain a bio-diverse ecosystem and to support the survival of various vegetation species. Climate change induced SWI into the surficial aquifer can lead to reduction of freshwater storage and alteration of the distribution and productivity of vegetation communities. In this study, a three-dimensional variable-density SEAWAT model is developed and calibrated to investigate the spatial and temporal variation of salinity level in the surficial aquifer of CCBIC. We link the SEAWAT model to surge model data to examine the effects of storm surge from Hurricane Jeanne. Simulation results indicate that the surficial aquifer salinity level increases significantly right after the occurrence of storm surge because of high aquifer permeability and rapid infiltration and diffusion of the overtopping saltwater, while the surficial aquifer salinity level begins to decrease after the fresh groundwater recharge from the storm's rainfall. The tropical storm precipitation generates an effective hydraulic barrier further impeding SWI and providing seaward freshwater discharge for saltwater dilution and flushing. To counteract the catastrophic effects of storm surge, this natural remediation process may take at least 15-20 years or even several decades. These simulation results contribute to ongoing research focusing on forecasting regional vegetation community responses to climate change, and are expected to provide a useful reference for climate change adaptation planning

The value of the exergetic life cycle assessment besides the LCA

NARCIS (Netherlands)

Cornelissen, Rene; Hirs, Gerard

2002-01-01

In this paper the value of the exergetic life cycle assessment (ELCA) has been analysed. The ELCA uses the framework of the life cycle assessment (LCA) and can be seen as the exergy analysis of a complete life cycle. The value of the ELCA besides the LCA has been discussed. It is shown that the ELCA

Interaction of coastal urban groundwater with infrastructure due to tidal variation

Science.gov (United States)

Su, X.; Prigiobbe, V.

2017-12-01

The urbanization of coastal areas has been increasing during the last century. For these areas, groundwater is one of major source of potable water for the population, the industry, and the agriculture, with an average demand of 30 m3/s [1,2]. Simultaneously, the rate of sea-level rise has been recorded to be approximately 40 mm/yr [3], with potential negative consequences on the coastal groundwater. As the sea-level rises, sea-water intrusion into potable aquifers may become more important [4] and the water table of the shallow aquifer underneath the coastal areas may rise [5]. Therefore, the water quality of the aquifer decreases and interaction between the shallow aquifer and infrastructure may occur. In particular, in the latter case, disruptive events may become more frequent, such as infiltration of groundwater into damaged sewer causing discharge of untreated sewage (combined sewer overflows, CSOs). Here, a study is presented on the modeling of urban groundwater in coastal areas to identify the cause of frequent CSOs in dry weather conditions, i.e., CSOs are not expected to occur. The evolution of the water table was described in response of tidal variation to quantify the interaction between the shallow aquifer and an aging sewer. The watershed of the city of Hoboken (NJ), at the estuary of Hudson river, was implemented in MODFLOW. The model was built using dataset from various sources. Geostatistic was applied to create the aquifer geology and measurements of the water table from monitoring wells within the urban area were used as boundary conditions and model validation. Preliminary results of the simulations are shown the figure, where the water table over a period of 7 months was calculated. The groundwater model with the sewer will help identifying the parts of the network that might be submerged by the groundwater and, therefore, subjected to infiltration. Combining groundwater and sewer modeling with the hydrograph separation method [6], the model

Documentation of a groundwater flow model developed to assess groundwater availability in the Northern Atlantic Coastal Plain aquifer system from Long Island, New York, to North Carolina

Science.gov (United States)

Masterson, John P.; Pope, Jason P.; Fienen, Michael N.; Monti, Jr., Jack; Nardi, Mark R.; Finkelstein, Jason S.

2016-08-31

The U.S. Geological Survey developed a groundwater flow model for the Northern Atlantic Coastal Plain aquifer system from Long Island, New York, to northeastern North Carolina as part of a detailed assessment of the groundwater availability of the area and included an evaluation of how these resources have changed over time from stresses related to human uses and climate trends. The assessment was necessary because of the substantial dependency on groundwater for agricultural, industrial, and municipal needs in this area.The three-dimensional, groundwater flow model developed for this investigation used the numerical code MODFLOW–NWT to represent changes in groundwater pumping and aquifer recharge from predevelopment (before 1900) to future conditions, from 1900 to 2058. The model was constructed using existing hydrogeologic and geospatial information to represent the aquifer system geometry, boundaries, and hydraulic properties of the 19 separate regional aquifers and confining units within the Northern Atlantic Coastal Plain aquifer system and was calibrated using an inverse modeling parameter-estimation (PEST) technique.The parameter estimation process was achieved through history matching, using observations of heads and flows for both steady-state and transient conditions. A total of 8,868 annual water-level observations from 644 wells from 1986 to 2008 were combined into 29 water-level observation groups that were chosen to focus the history matching on specific hydrogeologic units in geographic areas in which distinct geologic and hydrologic conditions were observed. In addition to absolute water-level elevations, the water-level differences between individual measurements were also included in the parameter estimation process to remove the systematic bias caused by missing hydrologic stresses prior to 1986. The total average residual of –1.7 feet was normally distributed for all head groups, indicating minimal bias. The average absolute residual value

Recent LCA Developments In Waste Management

DEFF Research Database (Denmark)

Christensen, Thomas Højlund; Astrup, Thomas Fruergaard; Brogaard, Line Kai-Sørensen

2015-01-01

Based on 10 years of experience we briefly present key issues which should receive special attention when waste LCA is performed. Attention paid to the importance of good data on waste composition, the contribution of environmental impacts from capital goods, assessing the value of recovered mate...

Estimating pesticide emission fractions for use in LCA: A global consensus-building effort

DEFF Research Database (Denmark)

Fantke, Peter; Anton, Assumpcio; Basset-Mens, Claudine

2016-01-01

agreement on recommended default agricultural pesticide emission fractions to environmental media. Consensual decisions on the assessment framework are (a) primary distributions are used as inputs for LCIA, while further investigating how to assess secondary emissions, (b) framework and LCA application...... and application method scenarios will be based on sensitiv ity analysis, (g) default emission estimates for LCA will be derived from production-weighted averages, and (h) emission fractions will be reported spatially disaggregated. Recommendations for LCA practitioners and database developers are (a) LCA studies...... the field as part of technosphere and ecosphere, (e) fate and exposure processes should be included in LCIA (e.g. crop uptake), (f) default emission estimates should be used in absence of detailed scenario data, (g) and all assumptions should be reported. The recommended pesticide emission fractions results...

Alpha-emitting isotopes and chromium in a coastal California aquifer

International Nuclear Information System (INIS)

Densmore, Jill N.; Izbicki, John A.; Murtaugh, Joseph M.; Swarzenski, Peter W.; Bullen, Thomas D.

2014-01-01

Highlights: • Alluvium in Piedra de Lumbre basin higher radionuclides likely from natural Th. • Natural uranium decay-chain isotopes, including Ra, present in marine deposits. • Marine deposits also contain low concentrations of chromium. • Radionuclides and chromium concentrations lower in alluvium in the Las Flores basin. - Abstract: The unadjusted 72-h gross alpha activities in water from two wells completed in marine and alluvial deposits in a coastal southern California aquifer 40 km north of San Diego were 15 and 25 picoCuries per liter (pCi/L). Although activities were below the Maximum Contaminant Level (MCL) of 15 pCi/L, when adjusted for uranium activity; there is concern that new wells in the area may exceed MCLs, or that future regulations may limit water use from the wells. Coupled well-bore flow and depth-dependent water-quality data collected from the wells in 2011 (with analyses for isotopes within the uranium, actinium, and thorium decay-chains) show gross alpha activity in marine deposits is associated with decay of naturally-occurring 238 U and its daughter 234 U. Radon activities in marine deposits were as high as 2230 pCi/L. In contrast, gross alpha activities in overlying alluvium within the Piedra de Lumbre watershed, eroded from the nearby San Onofre Hills, were associated with decay of 232 Th, including its daughter 224 Ra. Radon activities in alluvium from Piedra de Lumbre of 450 pCi/L were lower than in marine deposits. Chromium VI concentrations in marine deposits were less than the California MCL of 10 μg/L (effective July 1, 2014) but δ 53 Cr compositions were near zero and within reported ranges for anthropogenic chromium. Alluvial deposits from the nearby Las Flores watershed, which drains a larger area having diverse geology, has low alpha activities and chromium as a result of geologic and geochemical conditions and may be more promising for future water-supply development

Sediment distribution and hydrologic conditions of the Potomac aquifer in Virginia and parts of Maryland and North Carolina

Science.gov (United States)

McFarland, Randolph E.

2013-01-01

Sediments of the heavily used Potomac aquifer broadly contrast across major structural features of the Atlantic Coastal Plain Physiographic Province in eastern Virginia and adjacent parts of Maryland and North Carolina. Thicknesses and relative dominance of the highly interbedded fluvial sediments vary regionally. Vertical intervals in boreholes of coarse-grained sediment commonly targeted for completion of water-supply wells are thickest and most widespread across the central and southern parts of the Virginia Coastal Plain. Designated as the Norfolk arch depositional subarea, the entire sediment thickness here functions hydraulically as a single interconnected aquifer. By contrast, coarse-grained sediment intervals are thinner and less widespread across the northern part of the Virginia Coastal Plain and into southern Maryland, designated as the Salisbury embayment depositional subarea. Fine-grained intervals that are generally avoided for completion of water-supply wells are increasingly thick and widespread northward. Fine-grained intervals collectively as thick as several hundred feet comprise two continuous confining units that hydraulically separate three vertically spaced subaquifers. The subaquifers are continuous northward but merge southward into the single undivided Potomac aquifer. Lastly, far southeastern Virginia and northeastern North Carolina are designated as the Albemarle embayment depositional subarea, where both coarse- and fine-grained intervals are of only moderate thickness. The entire sediment thickness functions hydraulically as a single interconnected aquifer. A substantial hydrologic separation from overlying aquifers is imposed by the upper Cenomanian confining unit. Potomac aquifer sediments were deposited by a fluvial depositional complex spanning the Virginia Coastal Plain approximately 100 to 145 million years ago. Westward, persistently uplifted granite and gneiss source rocks sustained a supply of coarse-grained sand and gravel

Stratigraphic controls on saltwater intrusion in the Dominguez Gap area of coastal Los Angeles

Science.gov (United States)

Edwards, B.D.; Ehman, K.D.; Ponti, D.J.; Reichard, E.G.; Tinsley, J.C.; Rosenbauer, R.J.; Land, M.

2009-01-01

The Los Angeles Basin is a densely populated coastal area that significantly depends on groundwater. A part of this groundwater supply is at risk from saltwater intrusion-the impetus for this study. High-resolution seismic-reflection data collected from the Los Angeles-Long Beach Harbor Complex have been combined with borehole geophysical and descriptive geological data from four nearby ??400-m-deep continuously cored wells and with borehole geophysical data from adjacent water and oil wells to characterize the Pliocene to Holocene stratigraphy of the Dominguez Gap coastal aquifer system. The new data are shown as a north-south, two- dimensional, sequence-stratigraphic model that is compared to existing lithostratigraphic models of the Los Angeles Basin in an attempt to better understand pathways of saltwater intrusion into coastal aquifers. Intrusion of saltwater into the coastal aquifer system generally is attributed to over-pumping that caused the hydraulic gradient to reverse during the mid-1920s. Local water managers have used the existing lithostratigraphic model to site closely spaced injection wells of freshwater (barrier projects) attempting to hydraulically control the saltwater intrusion. Improved understanding of the stratigraphic relationships can guide modifications to barrier design that will allow more efficient operation. Allostratigraphic nomenclature is used to define a new sequence-stratigraphic model for the area because the existing lithostratigraphic correlations that have been used to define aquifer systems are shown not to be time-correlative. The youngest sequence, the Holocene Dominguez sequence, contains the Gaspur aquifer at its base. The Gaspur aquifer is intruded with saltwater and consists of essentially flat-lying gravelly sands deposited by the ancestral Los Angeles River as broad channels that occupied a paleovalley incised into the coastal plain during the last glacio-eustatic highstand. The underlying sequences are deformed into

Water quality considerations on the rise as the use of managed aquifer recharge systems widens

OpenAIRE

Hartog, Niels; Stuyfzand, Pieter J.

2017-01-01

Managed Aquifer Recharge (MAR) is a promising method of increasing water availability in water stressed areas by subsurface infiltration and storage, to overcome periods of drought, and to stabilize or even reverse salinization of coastal aquifers. Moreover, MAR could be a key technique in making alternative water resources available, such as reuse of communal effluents for agriculture, industry and even indirect potable reuse. As exemplified by the papers in this Special Issue, consideration...

Karst connections between unconfined aquifers and the Upper Floridan aquifer in south Georgia: geophysical evidence and hydrogeological models

Science.gov (United States)

Thieme, D. M.; Denizman, C.

2011-12-01

Buried karst features in sedimentary rocks of the south Georgia Coastal Plain present a challenge for hydrogeological models of recharge and confined flow within the underlying Upper Floridan aquifer. The Withlacoochee River, the trunk stream for the area, frequently disappears into subsurface caverns as it makes its way south to join the Suwannee River in northern Florida. The Withlacoochee also receives inputs from small ponds and bays which in turn receive spring and seep groundwater inputs. We have mapped karst topography at the "top of rock" using ground-penetrating radar (GPR). Up to seven meters of relief is indicated for the paleotopography on Miocene to Pliocene rocks, contrasting with the more subdued relief of the modern landscape. Current stratigraphic and hydrogeological reconstructions do not incorporate this amount of relief or lateral variation in the confining beds. One "pipe" which is approximately four meters in diameter is being mapped in detail. We have field evidence at this location for rapid movement of surficial pond and river water with a meteoric signature through several separate strata of sedimentary rock into an aquifer in the Hawthorn formation. We use our geophysical and hydrological field evidence to constrain quantitative hydrogeological models for the flow rates into and out of both this upper aquifer and the underlying Upper Floridan aquifer, which is generally considered to be confined by the clays of the Hawthorn.

LCA of Wastewater Treatment

DEFF Research Database (Denmark)

Larsen, Henrik Fred

2018-01-01

of LCA studies addressing wastewater treatment have from the very first published cases, been on energy and resource consumption. In recent time, the use of characterisation has increased and besides global warming potential, especially eutrophication is in focus. Even the toxicity-related impact......The main purpose of wastewater treatment is to protect humans against waterborne diseases and to safeguard aquatic bio-resources like fish. The dominating environmental concerns within this domain are indeed still potential aquatic eutrophication/oxygen depletion due to nutrient/organic matter...

Summary of northern Atlantic coastal plain hydrology and its relation to disposal of high-level radioactive waste in buried crystalline rock; a preliminary appraisal

Science.gov (United States)

Lloyd, O.B.; Larson, J.D.; Davis, R.W.

1985-01-01

Interpretation of available hydrologic data suggests that some areas beneath the Coastal Plain in the States of Delaware, Maryland, New Jersey, North Carolina, and Virginia might have some potential for the disposal of nuclear waste in crystalline rock that is buried beneath the Coastal Plain sediments. The areas of major interest occur where the top of the basement rock lies between 1,000 and 4,000 feet below sea level, the aquifer(s) immediately above the basement rock are saturated with saline water, confining material overlies the saline water bearing aquifer(s), and groundwater flow in the saline water aquifer(s) can be established. Preliminary data on (1) the distribution and thickness of the lowermost aquifers and confining beds, (2) the distribution of hydraulic conductivity in the lowermost aquifers, (3) estimated hydraulic heads and inferred direction of lateral groundwater flow for 1980, and (4) the distribution of saline water and brine, indicate eastern parts of the study area relatively best meet most of the criteria proposed for sediments that would overlie any potential buried crystalline-rock disposal site.

Coastal submarine springs in Lebanon and Syria: Geological, geochemical, and radio-isotopic study

International Nuclear Information System (INIS)

Al-Charideh, A.

2004-10-01

The coastal karst aquifer system (upper Cretaceous) and the submarine springs in the Syrian coast have been studies using chemical and isotopic methods in order to determine the hydraulic connections between the groundwater and the submarine springs. Results show that the groundwater and submarine springs are having the same slope on the σ 18 O/σ 2 H plot indicate the same hydrological origin for both. In addition this relation is very close to the local meteoric water line (LMWL) reflecting a rapid infiltration of rainfall to recharge coastal aquifer. The calculated percentage of freshwater in the two locations (Bassieh and Tartous) range from 20 to 96%. The estimation rate of the permanent submarine springs (BS1, BS2 and TS2, TS3) is 11m 3 /s or 350 million m 3 /y. The maximum residence time of the groundwater in the Cenomanian/Turonian aquifer was estimated at around 8 years, using the piston-flow model.(author)

How methodological choices affect LCA climate impact results: the case of structural timber

DEFF Research Database (Denmark)

De Rosa, Michele; Pizzol, Massimo; Schmidt, Jannick

2018-01-01

Purpose Life cycle assessment (LCA) is broadly applied to assess the environmental impact of products through their life cycle. LCA of bio-based products is particularly challenging due to the uncertainties in modeling the natural biomass production process. While uncertainties related to invento...

Contribution of a combined TDEM (Time-Domain electromagnetism) and geoelectrical survey to the investigation of the coastal aquifer of Puerto Morelos, Quintana Roo, Mexico

Science.gov (United States)

Rebolledo-Vieyra, M.; Ravelo-Cervantes, J. I.; Lecossec, A.

2007-12-01

This study reports initial results of combined Time Domain Electromagnetic (TDEM) and vertical electrical sounding (VES), geophysical characterization of the Quintana Roo coastal aquifer, with the aim of establishing effective protocols for subsequent surveys in the area, through the association of TDEM and VES. The high resistivity of the carbonate terrain, combined with the very low resistivity range of fresh-water and sea-water, are ideal to use both tools in combination. The results show that both methods used in a combination may provide a useful tool for hydrogeologial studies. In this survey we were able to identifiy a fracture 100 m x 40 m, that was correlated to fresh-water discharges in to the Puerto Morelos Reef lagoon.

LCA of a condensing boiler according to EuP Directive

International Nuclear Information System (INIS)

Tremonti, M.; Breedvelt, L.; Padovan, G.; Bosio, S.; Corsini, M.

2008-01-01

In the light of the EuP Directive (2005/32/EC), producers of Energy using Product (EuP) are obliged to initiate eco design activities. Fourteen product groups are currently under study, one being the preparatory EC study Eco Boiler, and will result in a EuP Working Plan. The LCA of a condensing boiler, commissionated by an Italian SME in the Lombardy Region, has been conducted to support its environmental strategy and communication, to start implementing eco design activities and to anticipate implications to the EuP Directive. In line with the Eco Boiler study, no detailed LCA has been applied, instead a simplified LCA proves to be a strategic tool to support the company environmental objectives. Specifically, the condensing boiler (the option with the best environmental performance and the lowest life cycle costs for the final consumer) has been internally compared to other boilers, resulting in useful eco design recommendations

Characterization of mechanisms and processes of groundwater salinization in irrigated coastal area using statistics, GIS, and hydrogeochemical investigations.

Science.gov (United States)

Bouzourra, Hazar; Bouhlila, Rachida; Elango, L; Slama, Fairouz; Ouslati, Naceur

2015-02-01

Coastal aquifers are at threat of salinization in most parts of the world. This study was carried out in coastal shallow aquifers of Aousja-Ghar El Melh and Kalâat el Andalous, northeastern of Tunisia with an objective to identify sources and processes of groundwater salinization. Groundwater samples were collected from 42 shallow dug wells during July and September 2007. Chemical parameters such as Na(+), Ca(2+), Mg(2+), K(+), Cl(-), SO4 (2-), HCO3 (-), NO3 (-), Br(-), and F(-) were analyzed. The combination of hydrogeochemical, statistical, and GIS approaches was used to understand and to identify the main sources of salinization and contamination of these shallow coastal aquifers as follows: (i) water-rock interaction, (ii) evapotranspiration, (iii) saltwater is started to intrude before 1972 and it is still intruding continuously, (iv) irrigation return flow, (v) sea aerosol spray, and finally, (vi) agricultural fertilizers. During 2005/2006, the overexploitation of the renewable water resources of aquifers caused saline water intrusion. In 2007, the freshening of a brackish-saline groundwater occurred under natural recharge conditions by Ca-HCO3 meteoric freshwater. The cationic exchange processes are occurred at fresh-saline interfaces of mixtures along the hydraulic gradient. The sulfate reduction process and the neo-formation of clays minerals characterize the hypersaline coastal Sebkha environments. Evaporation tends to increase the concentrations of solutes in groundwater from the recharge areas to the discharge areas and leads to precipitate carbonate and sulfate minerals.

Review of LCA studies of solid waste management systems – Part I: Lessons learned and perspectives

International Nuclear Information System (INIS)

Laurent, Alexis; Bakas, Ioannis; Clavreul, Julie; Bernstad, Anna; Niero, Monia; Gentil, Emmanuel; Hauschild, Michael Z.; Christensen, Thomas H.

2014-01-01

Highlights: • We perform a critical review of 222 LCA studies of solid waste management systems. • Studies mainly concentrated in Europe with little application in developing countries. • Assessments of relevant waste types apart from household waste have been overlooked. • Local specificities of systems prevent a meaningful generalisation of the LCA results. • LCA should support recommendations representative of the local conditions. - Abstract: The continuously increasing solid waste generation worldwide calls for management strategies that integrate concerns for environmental sustainability. By quantifying environmental impacts of systems, life cycle assessment (LCA) is a tool, which can contribute to answer that call. But how, where and to which extent has it been applied to solid waste management systems (SWMSs) until now, and which lessons can be learnt from the findings of these LCA applications? To address these questions, we performed a critical review of 222 published LCA studies of SWMS. We first analysed the geographic distribution and found that the published studies have primarily been concentrated in Europe with little application in developing countries. In terms of technological coverage, they have largely overlooked application of LCA to waste prevention activities and to relevant waste types apart from household waste, e.g. construction and demolition waste. Waste management practitioners are thus encouraged to abridge these gaps in future applications of LCA. In addition to this contextual analysis, we also evaluated the findings of selected studies of good quality and found that there is little agreement in the conclusions among them. The strong dependence of each SWMS on local conditions, such as waste composition or energy system, prevents a meaningful generalisation of the LCA results as we find it in the waste hierarchy. We therefore recommend stakeholders in solid waste management to regard LCA as a tool, which, by its ability of

Review of LCA studies of solid waste management systems – Part I: Lessons learned and perspectives

Energy Technology Data Exchange (ETDEWEB)

Laurent, Alexis, E-mail: alau@dtu.dk [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Bakas, Ioannis [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Clavreul, Julie [Residual Resources Engineering, Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Bernstad, Anna [Water and Environmental Engineering, Department of Chemical Engineering, Lund University, 221 00 Lund (Sweden); Niero, Monia [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); ECO – Ecosystems and Environmental Sustainability, Department of Chemical and Biochemical Engineering, Technical University of Denmark, 4000 Roskilde (Denmark); Gentil, Emmanuel [Copenhagen Resource Institute, 1215 Copenhagen K (Denmark); Hauschild, Michael Z. [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Christensen, Thomas H. [Residual Resources Engineering, Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

2014-03-01

Highlights: • We perform a critical review of 222 LCA studies of solid waste management systems. • Studies mainly concentrated in Europe with little application in developing countries. • Assessments of relevant waste types apart from household waste have been overlooked. • Local specificities of systems prevent a meaningful generalisation of the LCA results. • LCA should support recommendations representative of the local conditions. - Abstract: The continuously increasing solid waste generation worldwide calls for management strategies that integrate concerns for environmental sustainability. By quantifying environmental impacts of systems, life cycle assessment (LCA) is a tool, which can contribute to answer that call. But how, where and to which extent has it been applied to solid waste management systems (SWMSs) until now, and which lessons can be learnt from the findings of these LCA applications? To address these questions, we performed a critical review of 222 published LCA studies of SWMS. We first analysed the geographic distribution and found that the published studies have primarily been concentrated in Europe with little application in developing countries. In terms of technological coverage, they have largely overlooked application of LCA to waste prevention activities and to relevant waste types apart from household waste, e.g. construction and demolition waste. Waste management practitioners are thus encouraged to abridge these gaps in future applications of LCA. In addition to this contextual analysis, we also evaluated the findings of selected studies of good quality and found that there is little agreement in the conclusions among them. The strong dependence of each SWMS on local conditions, such as waste composition or energy system, prevents a meaningful generalisation of the LCA results as we find it in the waste hierarchy. We therefore recommend stakeholders in solid waste management to regard LCA as a tool, which, by its ability of

Identifying the effects of human pressure on groundwater quality to support water management strategies in coastal regions: A multi-tracer and statistical approach (Bou-Areg region, Morocco)

Energy Technology Data Exchange (ETDEWEB)

Re, V., E-mail: re@unive.it [Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Calle Larga Santa Marta 2137, Dorsoduro, 40123 Venice (Italy); National Engineering School of Sfax (ENIS) - Laboratory of Radio-Analysis and Environment (LRAE) Sfax (Tunisia); Sacchi, E. [Department of Earth and Environmental Sciences, University of Pavia, Via Ferrata 1, 27100 Pavia (Italy); Mas-Pla, J. [Grup de Geologia Aplicada i Ambiental (GAIA), Centre de Geologia i Cartografia Ambientals (GEOCAMB), Department of Environmental Sciences, University of Girona, 17071 Girona (Spain); Catalan Institute for Water Research (ICRA), 17003 Girona (Spain); Menció, A. [Grup de Geologia Aplicada i Ambiental (GAIA), Centre de Geologia i Cartografia Ambientals (GEOCAMB), Department of Environmental Sciences, University of Girona, 17071 Girona (Spain); El Amrani, N. [Faculty of Sciences and techniques, University Hassan 1er, Settat (Morocco)

2014-12-01

Groundwater pollution from anthropogenic sources is a serious concern affecting several coastal aquifers worldwide. Increasing groundwater exploitation, coupled with point and non-point pollution sources, are the main anthropogenic impacts on coastal environments and are responsible for severe health and food security issues. Adequate management strategies to protect groundwater from contamination and overexploitation are of paramount importance, especially in arid prone regions, where coastal aquifers often represent the main freshwater resource to sustain human needs. The Bou-Areg Aquifer (Morocco) is a perfect example of a coastal aquifer constantly exposed to all the negative externalities associated with groundwater use for agricultural purposes, which lead to a general increase in aquifer salinization. In this study data on 61 water samples, collected in June and November 2010, were used to: (i) track groundwater composition changes related to the use of irrigation water from different sources, (ii) highlight seasonal variations to assess aquifer vulnerability, and (iii) present a reproducible example of multi-tracer approach for groundwater management in rural coastal areas. Hydrogeochemical results show that Bou-Areg groundwater is characterized by – high salinity, associated with a remarkable increase in bicarbonate content in the crop growing season, due to more intense biological activity in irrigated soils. The coupled multi-tracer and statistical analysis confirms the strong dependency on irrigation activities as well as a clear identification of the processes governing the aquifer’s hydrochemistry in the different seasons. Water Rock Interaction (WRI) dominates the composition of most of groundwater samples in the Low Irrigation season (L-IR) and Agricultural Return Flow (ARF) mainly affects groundwater salinization in the High Irrigation season (H-IR) in the same areas naturally affected by WRI. In the central part of the plain River Recharge (RR

Identifying the effects of human pressure on groundwater quality to support water management strategies in coastal regions: A multi-tracer and statistical approach (Bou-Areg region, Morocco)

International Nuclear Information System (INIS)

Re, V.; Sacchi, E.; Mas-Pla, J.; Menció, A.; El Amrani, N.

2014-01-01

Groundwater pollution from anthropogenic sources is a serious concern affecting several coastal aquifers worldwide. Increasing groundwater exploitation, coupled with point and non-point pollution sources, are the main anthropogenic impacts on coastal environments and are responsible for severe health and food security issues. Adequate management strategies to protect groundwater from contamination and overexploitation are of paramount importance, especially in arid prone regions, where coastal aquifers often represent the main freshwater resource to sustain human needs. The Bou-Areg Aquifer (Morocco) is a perfect example of a coastal aquifer constantly exposed to all the negative externalities associated with groundwater use for agricultural purposes, which lead to a general increase in aquifer salinization. In this study data on 61 water samples, collected in June and November 2010, were used to: (i) track groundwater composition changes related to the use of irrigation water from different sources, (ii) highlight seasonal variations to assess aquifer vulnerability, and (iii) present a reproducible example of multi-tracer approach for groundwater management in rural coastal areas. Hydrogeochemical results show that Bou-Areg groundwater is characterized by – high salinity, associated with a remarkable increase in bicarbonate content in the crop growing season, due to more intense biological activity in irrigated soils. The coupled multi-tracer and statistical analysis confirms the strong dependency on irrigation activities as well as a clear identification of the processes governing the aquifer’s hydrochemistry in the different seasons. Water Rock Interaction (WRI) dominates the composition of most of groundwater samples in the Low Irrigation season (L-IR) and Agricultural Return Flow (ARF) mainly affects groundwater salinization in the High Irrigation season (H-IR) in the same areas naturally affected by WRI. In the central part of the plain River Recharge (RR

Broadening GHG accounting with LCA: application to a waste management business unit.

Science.gov (United States)

Fallaha, Sophie; Martineau, Geneviève; Bécaert, Valérie; Margni, Manuele; Deschênes, Louise; Samson, Réjean; Aoustin, Emmanuelle

2009-11-01

In an effort to obtain the most accurate climate change impact assessment, greenhouse gas (GHG) accounting is evolving to include life-cycle thinking. This study (1) identifies similarities and key differences between GHG accounting and life-cycle assessment (LCA), (2) compares them on a consistent basis through a case study on a waste management business unit. First, GHG accounting is performed. According to the GHG Protocol, annual emissions are categorized into three scopes: direct GHG emissions (scope 1), indirect emissions related to electricity, heat and steam production (scope 2) and other indirect emissions (scope 3). The LCA is then structured into a comparable framework: each LCA process is disaggregated into these three scopes, the annual operating activities are assessed, and the environmental impacts are determined using the IMPACT2002+ method. By comparing these two approaches it is concluded that both LCA and GHG accounting provide similar climate change impact results as the same major GHG contributors are determined for scope 1 emissions. The emissions from scope 2 appear negligible whereas emissions from scope 3 cannot be neglected since they contribute to around 10% of the climate change impact of the waste management business unit. This statement is strengthened by the fact that scope 3 generates 75% of the resource use damage and 30% of the ecosystem quality damage categories. The study also shows that LCA can help in setting up the framework for a annual GHG accounting by determining the major climate change contributors.

Monitoring the change of coastal zones from space

Science.gov (United States)

Cazenave, A. A.; Le Cozannet, G.; Benveniste, J.; Woodworth, P. L.

2017-12-01

The world's coastal zones, where an important fraction of the world population is currently living, are under serious threat because of coastal erosion, cyclones, storms, and salinization of estuaries and coastal aquifers. In the future, these hazards are expected to increase due to the combined effects of sea level rise, climate change, human activities and population increase. The response of coastal environments to natural and anthropogenic forcing factors (including climate change) depends on the characteristics of the forcing agents, as well as on the internal properties of the coastal systems, that remain poorly known and mostly un-surveyed at global scale. To better understand changes affecting coastal zones and to provide useful information to decision makers, various types of observations with global coverage need to be collected and analysed. Observations from space appear as an important complement to existing in situ observing systems (e.g., regional tide gauge networks). In this presentation, we discuss the benefit of systematic coastal monitoring from space, addressing both observations of forcing agents and of the coastal response. We highlight the need for a global coastal sea level data set based on retracked nadir altimetry missions and new SAR technology.

Systematic, efficient and consistent LCA calculations for chemical and biochemical processes

DEFF Research Database (Denmark)

Petchkaewkul, Kaesinee; Malakul, Pomthong; Gani, Rafiqul

2016-01-01

that allow a wider coverage of chemical and biochemical processes. Improvements of LCIA calculations and eco-efficiency evaluation are introduced. Also, a new model for photochemical ozone formation has been developed and implemented. Performance of LCSoft in terms of accuracy and reliability is compared......Life Cycle Assessment or LCA is a technique, which is applied for the study and evaluation of quantitative environmental impacts through the entire life cycle of products, processes or services in order to improve and/or evaluate the design of existing as well as new processes. The LCA factors can...... with another well-known LCA-software, SimaPro for a biochemical process – the production of bioethanol from cassava rhizome. The results show a very good match of new added impact categories. Also, the results from a new feature in LCSoft, which is eco-efficiency evaluation, are presented....

Influence of seasonal variations in sea level on the salinity regime of a coastal groundwater-fed wetland.

Science.gov (United States)

Wood, Cameron; Harrington, Glenn A

2015-01-01

Seasonal variations in sea level are often neglected in studies of coastal aquifers; however, they may have important controls on processes such as submarine groundwater discharge, sea water intrusion, and groundwater discharge to coastal springs and wetlands. We investigated seasonal variations in salinity in a groundwater-fed coastal wetland (the RAMSAR listed Piccaninnie Ponds in South Australia) and found that salinity peaked during winter, coincident with seasonal sea level peaks. Closer examination of salinity variations revealed a relationship between changes in sea level and changes in salinity, indicating that sea level-driven movement of the fresh water-sea water interface influences the salinity of discharging groundwater in the wetland. Moreover, the seasonal control of sea level on wetland salinity seems to override the influence of seasonal recharge. A two-dimensional variable density model helped validate this conceptual model of coastal groundwater discharge by showing that fluctuations in groundwater salinity in a coastal aquifer can be driven by a seasonal coastal boundary condition in spite of seasonal recharge/discharge dynamics. Because seasonal variations in sea level and coastal wetlands are ubiquitous throughout the world, these findings have important implications for monitoring and management of coastal groundwater-dependent ecosystems. © 2014, National Ground Water Association.

Harmonizing water management and social needs: a necessary condition for sustainable development. The case of Israel's coastal aquifer.

Science.gov (United States)

Melloul, Abraham J; Collin, Martin L

2003-04-01

This study focuses on the problem of most efficiently fulfilling the water requirements of society for sustainable water resources management. The goal is to coordinate effectively the social needs of the resident population with operational water resources management planning.The proposed approach consists of a pyramidal hierarchy of water resource management needs, similar to that suggested by psychologist Abraham Maslow for human social needs. The two pyramidal hierarchies can be simultaneously employed to delineate guidelines to synchronize planning for sustainable water resources development with the concerns and expectations of the resident population. In both hierarchies, higher level needs remain irrelevant and difficult to attain until lower level needs of the resident population have been fulfilled. Management planning measures employed with regard to Israel's coastal aquifer have been used to illustrate this approach. Observation of Israel's experience indicates markedly reduced effectiveness where such measures have failed to be properly synchronised with societal needs. Conversely, where hydrological management measures were successfully synchronized with societal concerns, increased efficiency towards attaining sustainable groundwater management was evident.

Life cycle assessment of products and technologies. LCA Symposium

Energy Technology Data Exchange (ETDEWEB)

Koukkari, H.; Nors, M. (eds.)

2009-12-15

VTT Technical Research Centre of Finland organised a Symposium 'Life Cycle Assessment of Products and Technologies' on the 6th of October, 2009. The Symposium gave a good overview of methods, tools and applications of Life Cycle Assessment developed and utilised in several technology fields of VTT. The 12 Symposium papers deal with recent LCA studies on products and technologies. The scope ranges from beverage cups to urban planning, from inventory databases to rating systems. Topical issues relating to climate change concern biorefineries and the overall impacts of the utilisation of biomass. The calculation of carbon footprints is also introduced through paper products and magazines. One example of LCA tools developed at VTT addresses cement manufacturing. VTT's transport emission database, LIPASTO, was introduced in detail. The use of LCA methods and life cycle thinking is described in various contexts: product development in relation to precision instruments; selection of materials and work processes in relation to sediment remediation project; and procedures of sustainability rating through VTT's office building Digitalo. The Climate Bonus project presented a demonstrated ICT support that informs about the greenhouse gas emissions and carbon footprints of households. (orig.)

Unsafe Practice of Extracting Potable Water From Aquifers in the Southwestern Coastal Region of Bangladesh

Science.gov (United States)

Chowdhury, S. H.; Ahmed, A. U.; Iqbal, M. Z.

2009-05-01

The groundwater resource is of paramount importance to the lives and livelihoods of the millions of people in Bangladesh. Unfortunately, high levels of arsenic have been found in groundwater in many parts of Bangladesh. Besides, the salinity in water systems in the coastal areas has increased as a consequence of the flow diversion from the upper reaches of Ganges River by the neighboring country India. Since hand- pumped groundwater (tube) wells are the only viable sources of drinking water, maintaining drinking water security for over 6 million people in the south-west (SW) region has been a major challenge for the Bangladesh Government. Due to rapid exploitation of groundwater resources in excess of recharge capacity, non-saline water sources in the SW region have already been depleted and the hand tube wells have mostly been abandoned. Meanwhile, shrimp farming has resulted in saline water infiltration into the perched aquifer system in many areas. A recent survey covering123 wells out of 184, extending to a depth of 330 m, showed high salinity in water. Combined factors of rapid exploitation of shallow groundwater, depletion of the deep aquifers and the subsequent saline water intrusion into these aquifers have put long-term sustainability of the remaining fresh groundwater resource into jeopardy. Very high concentrations of nitrite are found in this study in many tube wells in the area where samples have been drawn from aquifer systems up to 244 m deep. Nitrite concentrations in 35 wells randomly sampled in this study range from 16.98 to 43.11 mg/L, averaging 27.55 mg/L. This is much higher than the Maximum Contaminant Level (MCL) of 1 mg/L set by the U.S. EPA for human consumption. Simultaneously, dissolved oxygen (DO) is found to be very low (0.1 to 2 mg/L). There are numerous reports and anecdotal evidences of "Blue Baby Syndrome" (methemoglobinemia) in the region, which is generally due to gradual suffocation caused by poor transport of oxygen from the

An improved model for estimating pesticide emissions for agricultural LCA

DEFF Research Database (Denmark)

Dijkman, Teunis Johannes; Birkved, Morten; Hauschild, Michael Zwicky

2011-01-01

Credible quantification of chemical emissions in the inventory phase of Life Cycle Assessment (LCA) is crucial since chemicals are the dominating cause of the human and ecotoxicity-related environmental impacts in Life Cycle Impact Assessment (LCIA). When applying LCA for assessment of agricultural...... products, off-target pesticide emissions need to be quantified as accurately as possible because of the considerable toxicity effects associated with chemicals designed to have a high impact on biological organisms like for example insects or weed plants. PestLCI was developed to estimate the fractions...

Mutations in LCA5, encoding the ciliary protein lebercilin, cause Leber congenital amaurosis.

NARCIS (Netherlands)

Hollander, A.I. den; Koenekoop, R.K.; Mohamed, M.D.; Arts, H.H.; Boldt, K.; Towns, K.V.; Sedmak, T.; Beer, M. de; Nagel-Wolfrum, K.; McKibbin, M.; Dharmaraj, S.; Lopez, I.; Ivings, L.; Williams, G.A.; Springell, K.; Woods, C.G.; Jafri, H.; Rashid, Y.; Strom, T.M.; Zwaag, B. van der; Gosens, I.; Kersten, F.F.J.; Wijk, E. van; Veltman, J.A.; Zonneveld, M.N.; Beersum, S.E.C. van; Maumenee, I.H.; Wolfrum, U.; Cheetham, M.E.; Ueffing, M.; Cremers, F.P.M.; Inglehearn, C.F.; Roepman, R.

2007-01-01

Leber congenital amaurosis (LCA) causes blindness or severe visual impairment at or within a few months of birth. Here we show, using homozygosity mapping, that the LCA5 gene on chromosome 6q14, which encodes the previously unknown ciliary protein lebercilin, is associated with this disease. We

Numerical Simulation of Borehole Flow in Deep Monitor Wells, Pearl Harbor Aquifer, Oahu, Hawaii

Science.gov (United States)

Rotzoll, K.; Oki, D. S.; El-Kadi, A. I.

2010-12-01

Salinity profiles collected from uncased deep monitor wells are commonly used to monitor freshwater-lens thickness in coastal aquifers. However, vertical flow in these wells can cause the measured salinity to differ from salinity in the adjacent aquifer. Substantial borehole flow has been observed in uncased wells in the Pearl Harbor aquifer, Oahu, Hawaii. A numerical modeling approach, incorporating aquifer hydraulic characteristics and recharge rates representative of the Pearl Harbor aquifer, was used to evaluate the effects of borehole flow on measured salinity profiles from deep monitor wells. Borehole flow caused by vertical hydraulic gradients associated with the natural regional groundwater-flow system and local groundwater withdrawals was simulated. Model results were used to estimate differences between vertical salinity profiles in deep monitor wells and the adjacent aquifer in areas of downward, horizontal, and upward flow within the regional flow system—for cases with and without nearby pumped wells. Aquifer heterogeneity, represented in the model as layers of contrasting permeability, was incorporated in model scenarios. Results from this study provide insight into the magnitude of the differences between vertical salinity profiles from deep monitor wells and the salinity distributions in the aquifers. These insights are relevant and are critically needed for management and predictive modeling purposes.

Global warming impact assessment of a crop residue gasification project—A dynamic LCA perspective

International Nuclear Information System (INIS)

Yang, Jin; Chen, Bin

2014-01-01

Highlights: • A dynamic LCA is proposed considering time-varying factors. • Dynamic LCA is used to highlight GHG emission hotspots of gasification projects. • Indicators are proposed to reflect GHG emission performance. • Dynamic LCA alters the static LCA results. • Crop residue gasification project has high GHG abatement potential. - Abstract: Bioenergy from crop residues is one of the prevailing sustainable energy sources owing to the abundant reserves worldwide. Amongst a wide variety of energy conversion technologies, crop residue gasification has been regarded as promising owing to its higher energy efficiency than that of direct combustion. However, prior to large-scale application of crop residue gasification, the lifetime environmental performance should be investigated to shed light on sustainable strategies. As traditional static life cycle assessment (LCA) does not include temporal information for dynamic processes, we proposed a dynamic life cycle assessment approach, which improves the static LCA approach by considering time-varying factors, e.g., greenhouse gas characterization factors and energy intensity. As the gasification project can reduce greenhouse gas (GHG) discharge compared with traditional direct fuel combustion, trade-offs between the benefits of global warming mitigation and the impact on global warming of crop residue gasification should be considered. Therefore, indicators of net global warming mitigation benefit and global warming impact mitigation period are put forward to justify the feasibility of the crop residue gasification project. The proposed dynamic LCA and indicators were then applied to estimate the life cycle global warming impact of a crop residue gasification system in China. Results show that the crop residue gasification project has high net global warming mitigation benefit and a short global warming impact mitigation period, indicating its prominent potential in alleviating global warming impact. During

Electrical resistivity and porosity structure of the upper Biscayne Aquifer in Miami-Dade County, Florida

Science.gov (United States)

Whitman, Dean; Yeboah-Forson, Albert

2015-12-01

Square array electrical soundings were made at 13 sites in the Biscayne Aquifer distributed between 1 and 20 km from the shoreline. These soundings were modeled to investigate how resistivity varies spatially and with depth in the upper 15 m of the aquifer. Porosity was estimated from the modeled formation resistivity and observed pore fluid resistivity with Archie's Law. The models were used to interpolate resistivity and porosity surfaces at -2, -5, -8, and -15 m elevations. Modeled resistivity in the unsaturated zone is generally higher than 300 Ω m with the resistivity at sites with thick unsaturated zones greater than 1000 Ω m. Resistivity in the saturated zone ranges from 30 to 320 Ω m. At many sites in the western portions of the study area, resistivity is constant or increases with depth whereas sites in the center of the Atlantic Coastal Ridge exhibit a distinct low resistivity zone (ρ aquifer. The estimated porosity ranges between 14% and 71% with modal values near 25%. The porosity structure varies both with depth and spatially. Western sites exhibit a high porosity zone at shallow depths best expressed in a NE-SW trending zone of 40-50% porosity situated near the western margin of the Atlantic Coastal Ridge. This zone roughly corresponds in depth with the Q5 chronostratigraphic unit of the Miami Fm. which constitutes the upper flow unit of the Biscayne Aquifer. The highest porosity (>50%) is seen at elevations below -5 m at sites in the center of the Atlantic Coastal Ridge and likely corresponds to solution features. The general NE-SW trend of the resistivity and porosity structure suggests a causal connection with the Pleistocene paleogeography and sedimentary environments.

Origin and residence time of water in the Lima aquifer

International Nuclear Information System (INIS)

Montoya, Modesto; Mamani, Enoc

2013-01-01

The 8 million inhabitants of the coastal city Lima are supplied with water from the Rimac and Chillon rivers and water wells in the Lima aquifer. The history of the Rimac River flow and static level of water in its wells have been correlated to calculate the residence time of water in the aquifer it is recharged by the Rimac River until it reaches a well located 12 km away in the Miraflores District near the sea. The relative abundance of 2 H and 18 O are used to identify the origins of the waters from those wells, and the 3 H and 14 C contents are used to estimate the time after they fall as rain. (authors).

The study of coastal groundwater depth and salinity variation using time-series analysis

International Nuclear Information System (INIS)

Tularam, G.A.; Keeler, H.P.

2006-01-01

A time-series approach is applied to study and model tidal intrusion into coastal aquifers. The authors examine the effect of tidal behaviour on groundwater level and salinity intrusion for the coastal Brisbane region using auto-correlation and spectral analyses. The results show a close relationship between tidal behaviour, groundwater depth and salinity levels for the Brisbane coast. The known effect can be quantified and incorporated into new models in order to more accurately map salinity intrusion into coastal groundwater table

Cenomanian-Turonian aquifer of central Israel, its development and possible use as a storage reservoir

Science.gov (United States)

Schneider, Robert

1964-01-01

The Cenomanian-Turonian formations constitute a highly permeable dolomite and limestone aquifer in central Israel. The aquifer is on the west limb of an anticlinorium that trends north-northeast. In places it may be as much as 800 meters thick, but in the report area, largely the foothills of the Judean-Ephraim Mountains where the water development is most intensive, its thickness is generally considerably less. In some places the aquifer occurs at or near the land surface, or it is covered by sandy and gravelly coastal-plain deposits. However, in a large part of the area, it is overlain by as much as 400 meters of relatively impermeable strata, and it is probably underlain by less permeable Lower Cretaceous strata. In general the aquifer water is under artesian pressure. The porosity of the aquifer is characterized mainly by solution channels and cavities produced by jointing and faulting. In addition to the generally high permeability of the aquifer, some regions, which probably coincide with ancient drainage patterns and (or) fault zones, have exceptionally high permeabilities. The source of most of the water in the aquifer is believed to be rain that falls on the foothills area. The westward movement of ground water from the mountainous outcrop areas appears to be impeded by a zone of low permeability which is related to structural and stratigraphic conditions along the western side of the mountains. Gradients of the piezometric surface are small, and the net direction of water movement is westward and northwestward under natural conditions. Locally, however, the flow pattern may be in other directions owing to spatial variations in permeability in the aquifer, the location of natural discharge outlets, and the relation of the aquifer to adjacent geologic formations. There probably is also a large vertical component of flow. Pumping has modified the flow pattern by producing several irregularly shaped shallow depressions in the piezometric surface although, to

A thematic review of life cycle assessment (LCA) applied to pig production

International Nuclear Information System (INIS)

McAuliffe, Graham A.; Chapman, Deborah V.; Sage, Colin L.

2016-01-01

Commercial livestock production is known to have significant impacts on the environment. Pig production is a complex system which involves the production of animal feed, transportation, animal rearing and waste management. One tool for assessing the environmental performance of such complex systems is life cycle assessment (LCA). LCA has been applied to pig production considerably to date. This paper provides a chronological review of state-of-the-art pig production LCAs under three themes: feed production; entire-system livestock rearing; and waste management. The study considers how LCA applications have addressed technological improvements in animal husbandry, and highlights methodological limitations, particularly related to cross-study comparisons. Recent research demonstrates crude protein reduction in feed and anaerobic treatment of pig excreta resulting in bioenergy production are the key targets for environmental performance improvements related to pig production. - Highlights: • An extensive review of LCA applied to pig production is provided chronologically over the past decade. • Individual studies have been categorised into feed, whole-system pig production and waste management themes. • We consider how LCAs have addressed state-of-the-art pig husbandry. • We offer a discussion on key findings, limitations and future research.

A thematic review of life cycle assessment (LCA) applied to pig production

Energy Technology Data Exchange (ETDEWEB)

McAuliffe, Graham A., E-mail: g.a.mcauliffe@umail.ucc.ie [Department of Geography, University College Cork, O' Donovan' s Road, Cork (Ireland); School of Biological, Earth and Environmental Sciences, University College Cork, Distillery Fields, North Mall, Cork (Ireland); Chapman, Deborah V. [School of Biological, Earth and Environmental Sciences, University College Cork, Distillery Fields, North Mall, Cork (Ireland); Sage, Colin L. [Department of Geography, University College Cork, O' Donovan' s Road, Cork (Ireland)

2016-01-15

Commercial livestock production is known to have significant impacts on the environment. Pig production is a complex system which involves the production of animal feed, transportation, animal rearing and waste management. One tool for assessing the environmental performance of such complex systems is life cycle assessment (LCA). LCA has been applied to pig production considerably to date. This paper provides a chronological review of state-of-the-art pig production LCAs under three themes: feed production; entire-system livestock rearing; and waste management. The study considers how LCA applications have addressed technological improvements in animal husbandry, and highlights methodological limitations, particularly related to cross-study comparisons. Recent research demonstrates crude protein reduction in feed and anaerobic treatment of pig excreta resulting in bioenergy production are the key targets for environmental performance improvements related to pig production. - Highlights: • An extensive review of LCA applied to pig production is provided chronologically over the past decade. • Individual studies have been categorised into feed, whole-system pig production and waste management themes. • We consider how LCAs have addressed state-of-the-art pig husbandry. • We offer a discussion on key findings, limitations and future research.

Deliverable 4.1 Homogeneous LCA methodology agreed by NEPTUNE and INNOWATECH

DEFF Research Database (Denmark)

Larsen, Henrik Fred; Hauschild, Michael Zwicky; Wenzel, Henrik

2007-01-01

In order to do a life cycle assessment (LCA) of a waste water treatment technique, a system to handle the mapped inventory data and a life cycle impact assessment (LCIA) method/model is needed. Besides NEPTUNE, another EU-funded project has the same methodology need namely INNOWATECH (contract No....... 036882) running in parallel with NEPTUNE but focusing on industrial waste water. With the aim of facilitating cooperation between the two projects a common LCA methodology framework has been worked out and is described in the following. This methodology work has been done as a joint effort between...... NEPTUNE WP4 and INNOWATECH WP4 represented by the WP4 lead partner IVL. The aim of the co-operation is to establish common methodologies and/or LCA models and/or tools in order to achieve a homogenous approach in INNOWATECH and NEPTUNE. Further, the aim is to facilitate possibilities of data exchange...

Life cycle thinking in impact assessment—Current practice and LCA gains

Energy Technology Data Exchange (ETDEWEB)

Bidstrup, Morten, E-mail: Bidstrup@plan.aau.dk

2015-09-15

It has been advocated that life cycle thinking (LCT) should be applied in impact assessment (IA) to a greater extent, since some development proposals pose a risk of significant impacts throughout the interconnected activities of product systems. Multiple authors have proposed the usage of life cycle assessment (LCA) for such analytical advancement, but little to no research on this tool application has been founded in IA practice so far. The aim of this article is to elaborate further on the gains assigned to application of LCA. The research builds on a review of 85 Danish IA reports, which were analysed for analytical appropriateness and application of LCT. Through a focus on the non-technical summary, the conclusion and the use of specific search words, passages containing LCT were searched for in each IA report. These passages were then analysed with a generic framework. The results reveal that LCT is appropriate for most of the IAs, but that LCA is rarely applied to provide such a perspective. Without LCA, the IAs show mixed performance in regard to LCT. Most IAs do consider the product provision of development proposals, but they rarely relate impacts to this function explicitly. Many IAs do consider downstream impacts, but assessments of upstream, distant impacts are generally absent. It is concluded that multiple analytical gains can be attributed to greater application of LCA in IA practice, though some level of LCT already exists. - Highlights: • Life cycle thinking is appropriate across the types and topics of impact assessment. • Yet, life cycle assessment is rarely used for adding such perspective. • Impact assessment practice does apply some degree of life cycle thinking. • However, application of life cycle assessment could bring analytical gains.

Life cycle thinking in impact assessment—Current practice and LCA gains

International Nuclear Information System (INIS)

Bidstrup, Morten

2015-01-01

It has been advocated that life cycle thinking (LCT) should be applied in impact assessment (IA) to a greater extent, since some development proposals pose a risk of significant impacts throughout the interconnected activities of product systems. Multiple authors have proposed the usage of life cycle assessment (LCA) for such analytical advancement, but little to no research on this tool application has been founded in IA practice so far. The aim of this article is to elaborate further on the gains assigned to application of LCA. The research builds on a review of 85 Danish IA reports, which were analysed for analytical appropriateness and application of LCT. Through a focus on the non-technical summary, the conclusion and the use of specific search words, passages containing LCT were searched for in each IA report. These passages were then analysed with a generic framework. The results reveal that LCT is appropriate for most of the IAs, but that LCA is rarely applied to provide such a perspective. Without LCA, the IAs show mixed performance in regard to LCT. Most IAs do consider the product provision of development proposals, but they rarely relate impacts to this function explicitly. Many IAs do consider downstream impacts, but assessments of upstream, distant impacts are generally absent. It is concluded that multiple analytical gains can be attributed to greater application of LCA in IA practice, though some level of LCT already exists. - Highlights: • Life cycle thinking is appropriate across the types and topics of impact assessment. • Yet, life cycle assessment is rarely used for adding such perspective. • Impact assessment practice does apply some degree of life cycle thinking. • However, application of life cycle assessment could bring analytical gains

Hydraulic properties of the Midville Aquifer at the Savannah River Site, South Carolina

International Nuclear Information System (INIS)

Hodges, R.A.; Snipes, D.S.; Benson, S.M.; Daggett, J.S.; Temples, T.; Harrelson, L.

1994-01-01

Aquifer performance tests of the Midville Aquifer System were conducted at the Savannah River Site (SRS) in South Carolina. The stratigraphic section of interest consists of Late Cretaceous Coastal Plain sediments. Within the study area, the Midville Aquifer System is composed of sand aquifers separated by discontinuous clay lenses. The Midville is underlain by the Appleton Confining Unit which is separated from underlying Triassic sediments and Paleozoic crystallines by a regional unconformity. This unconformable surface has a dip of 10 m/km to the southeast. The Midville is overlain by the Allendale Confining Unit which separates the Midville from the Dublin Aquifer System. The tests were performed at B and P Areas within the SRS using production wells screened in the Midville Aquifer and monitor well clusters screened in the Midville, Dublin, and Gordon (Eocene) Aquifers. The B Area is located 13 km updip from P Area. The Midville is about 50 meters thick at B Area and 80 meters thick at P Area. The transmissivity of the Midville is 0.0095 m 2 /s at B Area and 0.017 m 2 /s at P Area. The storativity at both areas is about 10 -4 . Vertical leakance of the Midville is greater updip as the stratigraphic section thins. During the B Area test, pumping induced water level changes were detected in aquifers above the Midville. At P Area, no pumping induced water level changes were detected above the Midville Aquifer System

Potential and limitations of environmental design with LCA tools

Directory of Open Access Journals (Sweden)

Alexander Hollberg

2017-10-01

Full Text Available The built environment has a very high impact on the environment. Architects can largely define the environmental impact a building will cause throughout its lifetime through its design. Especially the choice of material and the type of construction can be influenced in early design stages. To quantify the environmental impact, tools for Life Cycle Assessment (LCA are used. This paper discusses the results of four case studies of applying four different novel LCA tools in four different academic courses at different universities. The results show that the success of applying LCA tools highly depends on the point of time during the design process and the design strategy the student pursues. If the right tool is used at the right moment and matches the design strategy, it can help to improve the architectural quality and reduce environmental impacts. In most cases however, the time of application did not fit, resulting in additional effort for applying the LCA tool. In consequence, the architectural elaboration of the design and the improvement of environmental performance compete against each other. Either the architectural quality suffers or the tool is employed late and the environmental performance cannot be improved. Even if the point in time of the tool application is right, the success depends highly on the design strategy. The number of tools is growing and there is an adequate tool available for each design stage. The design strategy has to match the tool and this requires a willingness to adapt the design approach. The issue of environmental design shifted from a lack of adequate tools to the lack of adequate design approaches. Tools can be easily taught in seminars. Environmental design strategies, however, have to be included in design studios and developed throughout the entire design phase to become part of architectural education.

The 2d-LCA as an alternative to x-wires

Science.gov (United States)

Puczylowski, Jaroslaw; Hölling, Michael; Peinke, Joachim

2015-11-01

The 2d-Laser Cantilever Anemometer (2d-LCA) is an innovative sensor for two-dimensional velocity measurements in fluids. It uses a micostructured cantilever made of silicon and SU-8 as a sensing element and is capable of performing mesurements with extremly high temporal resolutions up to 150kHz. The size of the cantilever defines its spatial resolution, which is in the order of 150 μm only. Another big feature is a large angular range of 180° in total. The 2d-LCA has been developed as an alternative measurement method to x-wires with the motivation to create a sensor that can operate in areas where the use of hot-wire anemometry is difficult. These areas include measurements in liquids and in near-wall or particle-laden flows. Unlike hot-wires, the resolution power of the 2d-LCA does not decrease with increasing flow velocity, making it particularly suitable for measurements in high speed flows. Comparative measurements with the 2d-LCA and hot-wires have been carried out in order to assess the performance of the new anemometer. The data of both measurement techniques were analyzed using the same stochastic methods including a spectral analysis as well as an inspection of increment statistics and structure functions. Furthermore, key parameters, such as mean values of both velocity components, angles of attack and the characteristic length scales were determined from both data sets. The analysis reveals a great agreement between both anemometers and thus confirms the new approach.

An innovative implementation of LCA within the EIA procedure: Lessons learned from two Wastewater Treatment Plant case studies

Energy Technology Data Exchange (ETDEWEB)

Larrey-Lassalle, Pyrène, E-mail: pyrene.larrey-lassalle@irstea.fr [Irstea, UMR ITAP, ELSA Research Group & ELSA-PACT Industrial Chair for Environmental and Social Sustainability Assessment, 361 rue Jean François Breton, F-34196 Montpellier (France); LGEI, Ecole des mines d' Alès, 6 avenue de Clavières, 30319 Alès Cedex (France); Catel, Laureline; Roux, Philippe; Rosenbaum, Ralph K. [Irstea, UMR ITAP, ELSA Research Group & ELSA-PACT Industrial Chair for Environmental and Social Sustainability Assessment, 361 rue Jean François Breton, F-34196 Montpellier (France); Lopez-Ferber, Miguel; Junqua, Guillaume [LGEI, Ecole des mines d' Alès, 6 avenue de Clavières, 30319 Alès Cedex (France); Loiseau, Eléonore [Irstea, UMR ITAP, ELSA Research Group & ELSA-PACT Industrial Chair for Environmental and Social Sustainability Assessment, 361 rue Jean François Breton, F-34196 Montpellier (France)

2017-03-15

Life Cycle Assessment (LCA) has been identified in the literature as a promising tool to increase the performance of environmental assessments at different steps in the Environmental Impact Assessment (EIA) procedure. However, few publications have proposed a methodology for an extensive integration, and none have compared the results with existing EIA conclusions without LCA. This paper proposes a comprehensive operational methodology for implementing an LCA within an EIA. Based on a literature review, we identified four EIA steps that could theoretically benefit from LCA implementation, i.e., (a) the environmental comparison of alternatives, (b) the identification of key impacts, (c) the impact assessment, and (d) the impact of mitigation measures. For each of these steps, an LCA was implemented with specific goal and scope definitions that resulted in a specific set of indicators. This approach has been implemented in two contrasting Wastewater Treatment Plant (WWTP) projects and compared to existing EIA studies. The results showed that the two procedures, i.e., EIAs with or without inputs from LCA, led to different conclusions. The environmental assessments of alternatives and mitigation measures were not carried out in the original studies and showed that other less polluting technologies could have been chosen. Regarding the scoping step, the selected environmental concerns were essentially different. Global impacts such as climate change or natural resource depletion were not taken into account in the original EIA studies. Impacts other than those occurring on the project site (off-site impacts) were not assessed, either. All these impacts can be significant compared to those initially considered. On the other hand, unlike current LCA applications, EIAs usually address natural and technological risks and neighbourhood disturbances such as noises or odours, which are very important for the public acceptability of projects. Regarding the impact assessment

An innovative implementation of LCA within the EIA procedure: Lessons learned from two Wastewater Treatment Plant case studies

International Nuclear Information System (INIS)

Larrey-Lassalle, Pyrène; Catel, Laureline; Roux, Philippe; Rosenbaum, Ralph K.; Lopez-Ferber, Miguel; Junqua, Guillaume; Loiseau, Eléonore

2017-01-01

Life Cycle Assessment (LCA) has been identified in the literature as a promising tool to increase the performance of environmental assessments at different steps in the Environmental Impact Assessment (EIA) procedure. However, few publications have proposed a methodology for an extensive integration, and none have compared the results with existing EIA conclusions without LCA. This paper proposes a comprehensive operational methodology for implementing an LCA within an EIA. Based on a literature review, we identified four EIA steps that could theoretically benefit from LCA implementation, i.e., (a) the environmental comparison of alternatives, (b) the identification of key impacts, (c) the impact assessment, and (d) the impact of mitigation measures. For each of these steps, an LCA was implemented with specific goal and scope definitions that resulted in a specific set of indicators. This approach has been implemented in two contrasting Wastewater Treatment Plant (WWTP) projects and compared to existing EIA studies. The results showed that the two procedures, i.e., EIAs with or without inputs from LCA, led to different conclusions. The environmental assessments of alternatives and mitigation measures were not carried out in the original studies and showed that other less polluting technologies could have been chosen. Regarding the scoping step, the selected environmental concerns were essentially different. Global impacts such as climate change or natural resource depletion were not taken into account in the original EIA studies. Impacts other than those occurring on the project site (off-site impacts) were not assessed, either. All these impacts can be significant compared to those initially considered. On the other hand, unlike current LCA applications, EIAs usually address natural and technological risks and neighbourhood disturbances such as noises or odours, which are very important for the public acceptability of projects. Regarding the impact assessment

Environmental assessment of solid waste landfilling technologies by means of LCA-modeling

DEFF Research Database (Denmark)

Manfredi, Simone; Christensen, Thomas Højlund

2009-01-01

By using life cycle assessment (LCA) modeling, this paper compares the environmental performance of six landfilling technologies (open dump, conventional landfill with flares, conventional landfill with energy recovery, standard bioreactor landfill, flushing bioreactor landfill and semi......-aerobic landfill) and assesses the influence of the active operations practiced on these performances. The environmental assessments have been performed by means of the LCA-based tool EASEWASTE, whereby the functional unit utilized for the LCA is “landfilling of 1 ton of wet household waste in a 10 m deep landfill...... that it is crucially important to ensure the highest collection efficiency of landfill gas and leachate since a poor capture compromises the overall environmental performance. Once gas and leachate are collected and treated, the potential impacts in the standard environmental categories and on spoiled groundwater...

Cradle to Cradle and LCA – is there a conflict?

DEFF Research Database (Denmark)

Bjørn, Anders; Hauschild, Michael Zwicky

2011-01-01

The Cradle to Cradle (C2C) approach to ecodesign has been gaining increasing interest among industries, authorities and consumers over the last years. With its focus on resource conservation through closing loops, use of solar-based energy sources, avoidance of certain chemicals and the stated aim...... to create good rather than just avoid doing too much evil, it appeals more to industry than traditional LCA-based ecodesign. What are the real differences between the two approaches, and is there a conflict? Potential points of divergence between C2C and LCA are identified and the ability of C2C to support...

LCA-LCCA of oil fired steam turbine power plant in Singapore

International Nuclear Information System (INIS)

Kannan, R.; Tso, C.P.; Osman, Ramli; Ho, H.K.

2004-01-01

A life cycle assessment (LCA) was conducted to quantify the non-renewable energy use and global warming potential in electricity generation from a typical oil fired steam turbine plant in Singapore. As the conventional LCA does not include any cost analysis, which is a major criterion in decision making, the cost of power generation is estimated using a life cycle cost analysis (LCCA) tool. It is estimated that the hidden processes consumed about 9% additional energy on top of the fuel embedded energy, while the hidden GHG emission is about 12%. A correlation is established to estimate the life cycle energy use and GHG emissions directly from the power plant net efficiency. The study methodology, results and the empirical relations are presented, together with a brief overview of the Singapore power sector. It also highlights the need for consideration of the reserves availability in the pricing mechanism and how such cost indices could be developed based on the LCA-LCCA. (Author)

LCA-LCCA of oil fired steam turbine power plant in Singapore

International Nuclear Information System (INIS)

Kannan, R.; Tso, C.P.; Osman, Ramli; Ho, H.K.

2004-01-01

A life cycle assessment (LCA) was conducted to quantify the non-renewable energy use and global warming potential in electricity generation from a typical oil fired steam turbine plant in Singapore. As the conventional LCA does not include any cost analysis, which is a major criterion in decision making, the cost of power generation is estimated using a life cycle cost analysis (LCCA) tool. It is estimated that the hidden processes consumed about 9% additional energy on top of the fuel embedded energy, while the hidden GHG emission is about 12%. A correlation is established to estimate the life cycle energy use and GHG emissions directly from the power plant net efficiency. The study methodology, results and the empirical relations are presented, together with a brief overview of the Singapore power sector. It also highlights the need for consideration of the reserves availability in the pricing mechanism and how such cost indices could be developed based on the LCA-LCCA

Using Uncertainty Quantification to Guide Development and Improvements of a Regional-Scale Model of the Coastal Lowlands Aquifer System Spanning Texas, Louisiana, Mississippi, Alabama and Florida

Science.gov (United States)

Foster, L. K.; Clark, B. R.; Duncan, L. L.; Tebo, D. T.; White, J.

2017-12-01

Several historical groundwater models exist within the Coastal Lowlands Aquifer System (CLAS), which spans the Gulf Coastal Plain in Texas, Louisiana, Mississippi, Alabama, and Florida. The largest of these models, called the Gulf Coast Regional Aquifer System Analysis (RASA) model, has been brought into a new framework using the Newton formulation for MODFLOW-2005 (MODFLOW-NWT) and serves as the starting point of a new investigation underway by the U.S. Geological Survey to improve understanding of the CLAS and provide predictions of future groundwater availability within an uncertainty quantification (UQ) framework. The use of an UQ framework will not only provide estimates of water-level observation worth, hydraulic parameter uncertainty, boundary-condition uncertainty, and uncertainty of future potential predictions, but it will also guide the model development process. Traditionally, model development proceeds from dataset construction to the process of deterministic history matching, followed by deterministic predictions using the model. This investigation will combine the use of UQ with existing historical models of the study area to assess in a quantitative framework the effect model package and property improvements have on the ability to represent past-system states, as well as the effect on the model's ability to make certain predictions of water levels, water budgets, and base-flow estimates. Estimates of hydraulic property information and boundary conditions from the existing models and literature, forming the prior, will be used to make initial estimates of model forecasts and their corresponding uncertainty, along with an uncalibrated groundwater model run within an unconstrained Monte Carlo analysis. First-Order Second-Moment (FOSM) analysis will also be used to investigate parameter and predictive uncertainty, and guide next steps in model development prior to rigorous history matching by using PEST++ parameter estimation code.

Bridging the gap between LCA, LCC and CBA as sustainability assessment tools

Energy Technology Data Exchange (ETDEWEB)

Hoogmartens, Rob, E-mail: rob.hoogmartens@uhasselt.be [Hasselt University, Faculty of Business Economics, Centre for Environmental Sciences, Agoralaan, Building D, 3590 Diepenbeek (Belgium); Van Passel, Steven, E-mail: steven.vanpassel@uhasselt.be [Hasselt University, Faculty of Business Economics, Centre for Environmental Sciences, Agoralaan, Building D, 3590 Diepenbeek (Belgium); Van Acker, Karel, E-mail: karel.vanacker@lrd.kuleuven.be [Katholieke Universiteit Leuven, Department of Metallurgy and Materials Engineering, Kasteelpark Arenberg 44, 3001 Leuven (Belgium); Dubois, Maarten, E-mail: maarten.dubois@kuleuven.be [Katholieke Universiteit Leuven, Policy Research Centre for Sustainable Materials, Kasteelpark Arenberg 44, 3001 Leuven (Belgium)

2014-09-15

Increasing interest in sustainability has led to the development of sustainability assessment tools such as Life Cycle Analysis (LCA), Life Cycle Costing (LCC) and Cost–Benefit Analysis (CBA). Due to methodological disparity of these three tools, conflicting assessment results generate confusion for many policy and business decisions. In order to interpret and integrate assessment results, the paper provides a framework that clarifies the connections and coherence between the included assessment methodologies. Building on this framework, the paper further focuses on key aspects to adapt any of the methodologies to full sustainability assessments. Aspects dealt with in the review are for example the reported metrics, the scope, data requirements, discounting, product- or project-related and approaches with respect to scarcity and labor requirements. In addition to these key aspects, the review shows that important connections exist: (i) the three tools can cope with social inequality, (ii) processes such as valuation techniques for LCC and CBA are common, (iii) Environmental Impact Assessment (EIA) is used as input in both LCA and CBA and (iv) LCA can be used in parallel with LCC. Furthermore, the most integrated sustainability approach combines elements of LCA and LCC to achieve the Life Cycle Sustainability Assessment (LCSA). The key aspects and the connections referred to in the review are illustrated with a case study on the treatment of end-of-life automotive glass. - Highlights: • Proliferation of assessment tools creates ambiguity and confusion. • The developed assessment framework clarifies connections between assessment tools. • Broadening LCA, key aspects are metric and data requirements. • Broadening LCC, key aspects are scope, time frame and discounting. • Broadening CBA, focus point, timespan, references, labor and scarcity are key.

Bridging the gap between LCA, LCC and CBA as sustainability assessment tools

International Nuclear Information System (INIS)

Hoogmartens, Rob; Van Passel, Steven; Van Acker, Karel; Dubois, Maarten

2014-01-01

Increasing interest in sustainability has led to the development of sustainability assessment tools such as Life Cycle Analysis (LCA), Life Cycle Costing (LCC) and Cost–Benefit Analysis (CBA). Due to methodological disparity of these three tools, conflicting assessment results generate confusion for many policy and business decisions. In order to interpret and integrate assessment results, the paper provides a framework that clarifies the connections and coherence between the included assessment methodologies. Building on this framework, the paper further focuses on key aspects to adapt any of the methodologies to full sustainability assessments. Aspects dealt with in the review are for example the reported metrics, the scope, data requirements, discounting, product- or project-related and approaches with respect to scarcity and labor requirements. In addition to these key aspects, the review shows that important connections exist: (i) the three tools can cope with social inequality, (ii) processes such as valuation techniques for LCC and CBA are common, (iii) Environmental Impact Assessment (EIA) is used as input in both LCA and CBA and (iv) LCA can be used in parallel with LCC. Furthermore, the most integrated sustainability approach combines elements of LCA and LCC to achieve the Life Cycle Sustainability Assessment (LCSA). The key aspects and the connections referred to in the review are illustrated with a case study on the treatment of end-of-life automotive glass. - Highlights: • Proliferation of assessment tools creates ambiguity and confusion. • The developed assessment framework clarifies connections between assessment tools. • Broadening LCA, key aspects are metric and data requirements. • Broadening LCC, key aspects are scope, time frame and discounting. • Broadening CBA, focus point, timespan, references, labor and scarcity are key

Origin and residence time of water in the Lima aquifer

Energy Technology Data Exchange (ETDEWEB)

Montoya, Modesto [Instituto Peruano de Energia Nuclear, Av. Canada 1470, San Borja, Lima (Peru); Universidad Nacional de Ingenieria, Av. Tupac Amaru 210, Rimac, Lima (Peru); Mamani, Enoc [Direccion de Servicios, Instituto Peruano de Energia Nuclear, Av. Jose Saco km 12.5, Carabayllo, Lima (Peru)

2013-07-01

The 8 million inhabitants of the coastal city Lima are supplied with water from the Rimac and Chillon rivers and water wells in the Lima aquifer. The history of the Rimac River flow and static level of water in its wells have been correlated to calculate the residence time of water in the aquifer it is recharged by the Rimac River until it reaches a well located 12 km away in the Miraflores District near the sea. The relative abundance of {sup 2}H and {sup 18}O are used to identify the origins of the waters from those wells, and the {sup 3}H and {sup 14}C contents are used to estimate the time after they fall as rain. (authors).

LCA as a Tool to Evaluate Green Infrastructure's Environmental Performance

Science.gov (United States)

Catalano De Sousa, M.; Erispaha, A.; Spatari, S.; Montalto, F.

2011-12-01

Decentralized approaches to managing urban stormwater through use of green infrastructure (GI) often lead to system-wide efficiency gains within the urban watershed's energy supply system. These efficiencies lead to direct greenhouse gas (GHG) emissions savings, and also restore some ecosystem functions within the urban landscape. We developed a consequential life cycle assessment (LCA) model to estimate the life cycle energy, global warming potential (GWP), and payback times for each if GI were applied within a select neighborhood in New York City. We applied the SIMAPRO LCA software and the economic input-output LCA (EIO-LCA) tool developed by Carnegie Mellon University. The results showed that for a new intersection installation highlighted in this study a conventional infrastructure construction would emit and use approximately 3 times more for both CO2 and energy than a design using GI. Two GI benefits were analyzed with regards to retrofitting the existing intersection. The first was related to the savings in energy and CO2 at the Waste Water Treatment Plant via runoff reduction accrued from GI use. The second benefit was related to the avoided environmental costs associated with an additional new grey infrastructure installation needed to prevent CSO in case of no GI implementation. The first benefit indicated a high payback time for a GI installation in terms of CO2 and energy demand (80 and 90 years respectively) and suggest a slow energy and carbon recovery time. However, concerning to the second benefit, GI proved to be a sustainable alternative considering the high CO2 releases (429 MTE) and energy demand (5.5 TJ) associated with a grey infrastructure construction.

The Glasgow consensus on the delineation between pesticide emission inventory and impact assessment for LCA

DEFF Research Database (Denmark)

Rosenbaum, Ralph K.; Anton, Assumpció; Bengoa, Xavier

2015-01-01

Pesticides are applied to agricultural fields to optimise crop yield and their global use is substantial. Their consideration in life cycle assessment (LCA) is affected by important inconsistencies between the emission inventory and impact assessment phases of LCA. A clear definition...

The aquifer recharge: an overview of the legislative and planning aspect.

Science.gov (United States)

De Giglio, O; Caggiano, G; Apollonio, F; Marzella, A; Brigida, S; Ranieri, E; Lucentini, L; Uricchio, V F; Montagna, M T

2018-01-01

In most regions of the world, safeguarding groundwater resources is a serious issue, particularly in coastal areas where groundwater is the main water source for drinking, irrigation and industry. Water availability depends on climate, topography and geology. The aim of this paper is to evaluate aquifer recharge as a possible strategy to relieve water resource scarcity. Natural aquifer recharge is defined as the downward flow of water reaching the water table, increasing the groundwater reservoir. Hydro-meteorological factors (rainfall, evapotranspiration and runoff) may alter natural recharge processes. Artificial aquifer recharge is a process by which surface water is introduced with artificial systems underground to fill an aquifer. As a consequence of global warming that has increased the frequency and severity of natural disasters like the drought, the impacts of climate change and seasonality, the artificial recharge has been considered as a viable option. Different direct and indirect techniques can be used, and the choice depends on the hydrologic characteristics of a specific area. In Italy, Legislative Decree no. 152/06 plans artificial aquifer recharge as an additional measure in water management, and Decree no. 100/2016 establishes quantitative and qualitative conditions for recharge. Many projects examine aquifer recharge, such us WADIS-MAR in the southern Mediterranean region, WARBO in Italy and municipal wastewater treatment project in Apulia, a southern Italian region. However, aside from groundwater recharge, the community must foster a spirit of cooperation to manage groundwater as a sustainable resource.

Artesian water in the Malabar coastal plain of southern Kerala, India

Science.gov (United States)

Taylor, George C.; Ghosh, P.K.

1964-01-01

The present report is based on a geological and hydrological reconnaissance during 1954 of the Malabar Coastal Plain and adjacent island area of southern Kerala to evaluate the availability of ground water for coastal villages and municipalities and associated industries and the potentialities for future development. The work was done in cooperation with the Geological Survey of India and under the auspices of the U.S. Technical Cooperation Mission to India. The State of Kerala, which lies near the southern tip of India and along the eastern shore of the Caspian Sea, contains a total area of 14,937 square miles. The eastern part of the state is s rugged mountainous highland which attains altitudes of more than 6,000 feet. This highland descends westward through piedmont upland to s narrow coastal plain, which reaches a maximum width of about 16 miles in the latitude of Shertalli. A tropical monsoon rain-forest climate prevails in most of Kerala, and annual rainfall ranges from 65 to 130 inches in the southern part of the coastal plain to as much a 200 inches in the highland. The highland and piedmont upland tracts of Kerala are underlain by Precambrian meamorphic and igneous rocks belonging in large parabola-the so-called Charnockite Series. Beneath ahe coastal plain are semiconsolidated asunconsolidated sedimentary deposits whose age ranges from Miocene to Recent. These deposits include sofa sandstone and clay shale containing some marl or limestone and sand, and clay and pea containing some gravel. The sofa sandstone, sand, and gravel beds constitute important aquifers a depths ranging from a few tens of feet to 400 feet or more below the land surface. The shallow ground war is under water-able or unconfined conditions, but the deeper aquifers contain water under artesian pressure. Near the coast, drilled wells tapping the deeper aquifers commonly flow with artesian heads as much as 10 to 12 feet above the land surface. The draft from existing wells in the

Life cycle assessment (LCA of lead-free solders from the environmental protection aspect

Directory of Open Access Journals (Sweden)

Mitovski Aleksandra M.

2009-01-01

Full Text Available Life-cycle assessment (LCA presents a relatively new approach, which allows comprehensive environmental consequences analysis of a product system over its entire life. This analysis is increasingly being used in the industry, as a tool for investigation of the influence of the product system on the environment, and serves as a protection and prevention tool in ecological management. This method is used to predict possible influences of a certain material to the environment through different development stages of the material. In LCA, the product systems are evaluated on a functionally equivalent basis, which, in this case, was 1000 cubic centimeters of an alloy. Two of the LCA phases, life-cycle inventory (LCA and life-cycle impact assessment (LCIA, are needed to calculate the environmental impacts. Methodology of LCIA applied in this analysis aligns every input and output influence into 16 different categories, divided in two subcategories. The life-cycle assessment reaserch review of the leadfree solders Sn-Cu, SAC (Sn-Ag-Cu, BSA (Bi-Sb-Ag and SABC (Sn-Ag-Bi-Cu respectively, is given in this paper, from the environmental protection aspect starting from production, through application process and finally, reclamation at the end-of-life, i.e. recycling. There are several opportunities for reducing the overall environmental and human health impacts of solder used in electronics manufacturing based on the results of the LCA, such as: using secondary metals reclaimed through post-industrial recycling; power consumption reducing by replacing older, less efficient reflow assembly equipment, or by optimizing the current equipment to perform at the elevated temperatures required for lead-free soldering, etc. The LCA analysis was done comparatively in relation to widely used Sn-Pb solder material. Additionally, the impact factors of material consumption, energy use, water and air reserves, human health and ecotoxicity have been ALSO considered including

Simulation of saltwater intrusion in a poorly karstified coastal aquifer in Lebanon (Eastern Mediterranean)

Science.gov (United States)

Khadra, Wisam M.; Stuyfzand, Pieter J.

2018-03-01

To date, there has been no agreement on the best way to simulate saltwater intrusion (SWI) in karst aquifers. An equivalent porous medium (EPM) is usually assumed without justification of its applicability. In this paper, SWI in a poorly karstified aquifer in Lebanon is simulated in various ways and compared to measurements. Time series analysis of rainfall and aquifer response is recommended to decide whether quickflow through conduits can be safely ignored. This aids in justifying the selection of the exemplified EPM model. To examine the improvement of SWI representation when discrete features (DFs) are embedded in the model domain, the results of a coupled discrete-continuum (CDC) approach (a hybrid EPM-DF approach) are compared to the EPM model. The two approaches yielded reasonable patterns of hydraulic head and groundwater salinity, which seem trustworthy enough for management purposes. The CDC model also reproduced some local anomalous chloride patterns, being more adaptable with respect to the measurements. It improved the overall accuracy of salinity predictions at wells and better represented the fresh-brackish water interface. Therefore, the CDC approach can be beneficial in modeling SWI in poorly karstified aquifers, and should be compared with the results of the EPM method to decide whether the differences in the outcome at local scale warrant its (more complicated) application. The simulation utilized the SEAWAT code since it is density dependent and public domain, and it enjoys widespread application. Including DFs necessitated manual handling because the selected code has no built-in option for such features.

Beginning LCA. A guide into environmental life cycle assessment

Energy Technology Data Exchange (ETDEWEB)

Van den Berg, N.W. [ed.; Huppes, G. [Centre of Environmental Science CLM, Leiden University, Leiden (Netherlands); Dutilh, C.E. [Unilever, Van den Bergh Netherlands, Rotterdam (Netherlands)

1995-02-01

The main goal of this document is to provide practical guidance for those who want to start with Life Cycle Assessment (LCA). The document has been set up in the form of modules. Module 1 provides arguments to decide whether or not LCA is the right tool to use in a particular case. In this module other ways to study interactions with the environment will be mentioned as well. Module 2 explains the process of formulating the purpose and scope of the study. The results will give a general picture of the characteristics of the LCA. The next step, which is called the inventory analysis, represents the largest amount of work and is split up into four parts, i.e. Modules 3,4,5, and 6. Module 3 gives guidelines and detailed examples on how to construct a flowchart of the study. Module 5 describes how to collect the required data and Module 4 how to define the system boundaries. Finally, the processing of data is described in Module 6. The result of the inventory is a list of emissions and extractions for all processes involved in manufacturing and required for the functioning of a product, service or activity during the entire life cycle. Sometimes results are so clear that you may decide to stop after the inventory stage. Usually however, it is useful to carry out the impact assessment, which is split up into two parts (Modules 7 and 8). Instructions are given on how to translate the list of environmental interventions of the entire life cycle of the product into a table with scores on environmental themes: the classification/characterization. A basic substance list that might be used is added (Module 7). Also a description showing how to evaluate the results of the classification/characterization is given, so that conclusions may be drawn on the information that has been generated (Module 8). Module 9, the last module, describes how to complete the LCA. It provides suggestions on how to present the results and indications about the improvement analysis.

Comparative life cycle assessment (LCA) of biodiesel and fossil diesel fuel

International Nuclear Information System (INIS)

Spirinckx, C.; Xeuterick, D.

1997-01-01

Complementary to VlTO's demonstration project on the use of biodiesel as engine fuel (including on the road emission measurements) in Flanders, Belgium, a comparative life cycle assessment (LCA) has been carried out for rapeseed methyl ester (RME) and fossil diesel fuel. The primary concern of this study is the question as to whether or not the production of biodiesel is comparable to the production of fossil diesel fuel from an environmental point of view, taking into account all stages of the life cycle of these two products. The study covers: (1) a description of the LCA methodology used; (2) a definition of the goal and scope of the study: (3) an inventory of the consumption of energy and materials and the discharges to the environment, from the cradle to the grave, for both alternative fuels: (4) a comparative impact assessment; and (5) the interpretation of the results. The results of this comparative LCA can be used in the final decision making process next to the results of a social and economical assessment. 6 refs

Groundwater level responses to precipitation variability in Mediterranean insular aquifers

Science.gov (United States)

Lorenzo-Lacruz, Jorge; Garcia, Celso; Morán-Tejeda, Enrique

2017-09-01

Groundwater is one of the largest and most important sources of fresh water on many regions under Mediterranean climate conditions, which are exposed to large precipitation variability that includes frequent meteorological drought episodes, and present high evapotranspiration rates and water demand during the dry season. The dependence on groundwater increases in those areas with predominant permeable lithologies, contributing to aquifer recharge and the abundance of ephemeral streams. The increasing pressure of tourism on water resources in many Mediterranean coastal areas, and uncertainty related to future precipitation and water availability, make it urgent to understand the spatio-temporal response of groundwater bodies to precipitation variability, if sustainable use of the resource is to be achieved. We present an assessment of the response of aquifers to precipitation variability based on correlations between the Standardized Precipitation Index (SPI) at various time scales and the Standardized Groundwater Index (SGI) across a Mediterranean island. We detected three main responses of aquifers to accumulated precipitation anomalies: (i) at short time scales of the SPI (24 months). The differing responses were mainly explained by differences in lithology and the percentage of highly permeable rock strata in the aquifer recharge areas. We also identified differences in the months and seasons when aquifer storages are more dependent on precipitation; these were related to climate seasonality and the degree of aquifer exploitation or underground water extraction. The recharge of some aquifers, especially in mountainous areas, is related to precipitation variability within a limited spatial extent, whereas for aquifers located in the plains, precipitation variability influence much larger areas; the topography and geological structure of the island explain these differences. Results indicate large spatial variability in the response of aquifers to precipitation in

LCA of waste management systems: Development of tools for modeling and uncertainty analysis

DEFF Research Database (Denmark)

Clavreul, Julie

Since the late 1990s, life cycle assessment (LCA) has been increasingly applied to waste management to quantify direct, indirect and avoided impacts from various treatment options. The construction of inventories for waste management systems differs from classical product-LCAs in that (1...... to be modelled rather than monitored as in classical LCA (e.g. landfilling or the application of processed waste on agricultural land). Therefore LCA-tools are needed which specifically address these issues and enable practitioners to model properly their systems. In this thesis several pieces of work...... in waste treatment technologies. These material transfer functions specify how substances in input flows are transferred to output flows and environmental compartments and include for example processes for anaerobic digestion or landfill gas generation. • Offering a flexible user interface where the user...

Review of LCA studies of solid waste management systems – Part I: Lessons learned and perspectives

DEFF Research Database (Denmark)

Laurent, Alexis; Bakas, Ioannis; Clavreul, Julie

2014-01-01

distribution and found that the published studies have primarily been concentrated in Europe with little application in developing countries. In terms of technological coverage, they have largely overlooked application of LCA to waste prevention activities and to relevant waste types apart from household waste......The continuously increasing solid waste generation worldwide calls for management strategies that integrate concerns for environmental sustainability. By quantifying environmental impacts of systems, life cycle assessment (LCA) is a tool, which can contribute to answer that call. But how, where...... and to which extent has it been applied to solid waste management systems (SWMSs) until now, and which lessons can be learnt from the findings of these LCA applications? To address these questions, we performed a critical review of 222 published LCA studies of SWMS. We first analysed the geographic...

Involvement of LCA5 in Leber congenital amaurosis and retinitis pigmentosa in the Spanish population

NARCIS (Netherlands)

Corton, M.; Avila-Fernandez, A.; Vallespin, E.; Lopez-Molina, M.I.; Almoguera, B.; Martin-Garrido, E.; Tatu, S.D.; Khan, M.I.; Blanco-Kelly, F.; Riveiro-Alvarez, R.; Brion, M.; Garcia-Sandoval, B.; Cremers, F.P.M.; Carracedo, A.; Ayuso, C.

2014-01-01

OBJECTIVE: We aimed to identify novel genetic defects in the LCA5 gene underlying Leber congenital amaurosis (LCA) in the Spanish population and to describe the associated phenotype. DESIGN: Case series. PARTICIPANTS: A cohort of 217 unrelated Spanish families affected by autosomal recessive or

A Comprehensive evaluation of groundwater vulnerability to saltwater up-coning and sea water intrusion in a coastal aquifer (case study: Ghaemshahr-juybar aquifer)

Science.gov (United States)

Motevalli, Alireza; Moradi, Hamid Reza; Javadi, Saman

2018-02-01

Aquifer salinization has recently increased significantly due to human activity and has caused irreparable environmental and economic effects. In this research, a new method is proposed for modeling the vulnerability to salinity for the Ghaemshahr-juybar aquifer. Specifically, the GALDIT (Sea water intrusion) and TAWLBIC (Saltwater up-coning) indices were combined to produce a map of vulnerability (Comprehensive Salinity Index or CSI) to seawater intrusion of a region near the coast and saltwater up-coning away from the coast, respectively. Single parameter and removal layer sensitivity analysis were performed in order to identify the sensitive parameters and achieve optimal weights (through the single-parameter method) of contributing factors in all three methods. The three optimized methods produced were GALDIT-Opt, TAWLBIC-Opt and CSI-Opt. To assess the accuracy of the original maps and optimal ones, the Pearson correlation was used. Results indicated that the Pearson correlation of the optimized GALDIT, TAWLBIC and CSI model was better than GALDIT, TAWLBIC and CSI. The results show that the increase in correlation between EC (Electrical Conductivity), TDS (Total Dissolved Solids) and SAR (Sodium Adsorption Ratio) from the GALDIT model to the CSI-Opt model from values of 0.64, 0.56 and 0.68 has improved to values of 0.81, 0.88 and 0.91, respectively. The highest concentration of EC, with a value of 7050 μs/cm, is sampled in the areas of the east and northwest of the Ghaemshahr-juybar aquifer, which are classified in the CSI-Opt model as high and very high vulnerability levels. The highest concentration of TDS and SAR has been found in the east, northwest and northeast of the Ghaemshahr-juybar aquifer with a value of 4724 ppm for TDS and 14 mg/l for SAR that have been modeled in the CSI-Opt index as highly vulnerable areas. Eventually, CSI mapping can be used as an efficient tool in prioritizing in terms of the vulnerability to aquifer salinity, carrying out

Development of a Carbon Emission Calculations System for Optimizing Building Plan Based on the LCA Framework

Directory of Open Access Journals (Sweden)

Feifei Fu

2014-01-01

Full Text Available Life cycle thinking has become widely applied in the assessment for building environmental performance. Various tool are developed to support the application of life cycle assessment (LCA method. This paper focuses on the carbon emission during the building construction stage. A partial LCA framework is established to assess the carbon emission in this phase. Furthermore, five typical LCA tools programs have been compared and analyzed for demonstrating the current application of LCA tools and their limitations in the building construction stage. Based on the analysis of existing tools and sustainability demands in building, a new computer calculation system has been developed to calculate the carbon emission for optimizing the sustainability during the construction stage. The system structure and detail functions are described in this paper. Finally, a case study is analyzed to demonstrate the designed LCA framework and system functions. This case is based on a typical building in UK with different plans of masonry wall and timber frame to make a comparison. The final results disclose that a timber frame wall has less embodied carbon emission than a similar masonry structure. 16% reduction was found in this study.

Revision and extension of Eco-LCA metrics for sustainability assessment of the energy and chemical processes.

Science.gov (United States)

Yang, Shiying; Yang, Siyu; Kraslawski, Andrzej; Qian, Yu

2013-12-17

Ecologically based life cycle assessment (Eco-LCA) is an appealing approach for the evaluation of resources utilization and environmental impacts of the process industries from an ecological scale. However, the aggregated metrics of Eco-LCA suffer from some drawbacks: the environmental impact metric has limited applicability; the resource utilization metric ignores indirect consumption; the renewability metric fails to address the quantitative distinction of resources availability; the productivity metric seems self-contradictory. In this paper, the existing Eco-LCA metrics are revised and extended for sustainability assessment of the energy and chemical processes. A new Eco-LCA metrics system is proposed, including four independent dimensions: environmental impact, resource utilization, resource availability, and economic effectiveness. An illustrative example of comparing assessment between a gas boiler and a solar boiler process provides insight into the features of the proposed approach.

Are functional fillers improving environmental behavior of plastics? A review on LCA studies.

Science.gov (United States)

Civancik-Uslu, Didem; Ferrer, Laura; Puig, Rita; Fullana-I-Palmer, Pere

2018-06-01

The use of functional fillers can be advantageous in terms of cost reduction and improved properties in plastics. There are many types of fillers used in industry, organic and inorganic, with a wide application area. As a response to the growing concerns about environmental damage that plastics cause, recently fillers have started to be considered as a way to reduce it by decreasing the need for petrochemical resources. Life cycle assessment (LCA) is identified as a proper tool to evaluate potential environmental impacts of products or systems. Therefore, in this study, the literature regarding LCA of plastics with functional fillers was reviewed in order to see if the use of fillers in plastics could be environmentally helpful. It was interesting to find out that environmental impacts of functional fillers in plastics had not been studied too often, especially in the case of inorganic fillers. Therefore, a gap in the literature was identified for the future works. Results of the study showed that, although there were not many and some differences exist among the LCA studies, the use of fillers in plastics industry may help to reduce environmental emissions. In addition, how LCA methodology was applied to these materials was also investigated. Copyright © 2018 Elsevier B.V. All rights reserved.

How Well Does LCA Model Land Use Impacts on Biodiversity?--A Comparison with Approaches from Ecology and Conservation.

Science.gov (United States)

Curran, Michael; de Souza, Danielle Maia; Antón, Assumpció; Teixeira, Ricardo F M; Michelsen, Ottar; Vidal-Legaz, Beatriz; Sala, Serenella; Milà i Canals, Llorenç

2016-03-15

The modeling of land use impacts on biodiversity is considered a priority in life cycle assessment (LCA). Many diverging approaches have been proposed in an expanding literature on the topic. The UNEP/SETAC Life Cycle Initiative is engaged in building consensus on a shared modeling framework to highlight best-practice and guide model application by practitioners. In this paper, we evaluated the performance of 31 models from both the LCA and the ecology/conservation literature (20 from LCA, 11 from non-LCA fields) according to a set of criteria reflecting (i) model completeness, (ii) biodiversity representation, (iii) impact pathway coverage, (iv) scientific quality, and (v) stakeholder acceptance. We show that LCA models tend to perform worse than those from ecology and conservation (although not significantly), implying room for improvement. We identify seven best-practice recommendations that can be implemented immediately to improve LCA models based on existing approaches in the literature. We further propose building a "consensus model" through weighted averaging of existing information, to complement future development. While our research focuses on conceptual model design, further quantitative comparison of promising models in shared case studies is an essential prerequisite for future informed model choice.

Effect of an offshore sinkhole perforation in a coastal confined aquifer on submarine groundwater discharge

Science.gov (United States)

Fratesi, S.E.; Leonard, V.; Sanford, W.E.

2007-01-01

In order to explore submarine groundwater discharge in the vicinity of karst features that penetrate the confining layer of an offshore, partially confined aquifer, we constructed a three-dimensional groundwater model using the SUTRA (Saturated-Unsaturated TRAnsport) variable-density groundwater flow model. We ran a parameter sensitivity analysis, testing the effects of recharge rates, permeabilities of the aquifer and confining layer, and thickness of the confining layer. In all simulations, less than 20% of the freshwater recharge for the entire model exits through the sinkhole. Recirculated seawater usually accounts for 10-30% of the total outflow from the model. Often, the sinkhole lies seaward of the transition zone and acts as a recharge feature for recirculating seawater. The permeability ratio between aquifer and confining layer influences the configuration of the freshwater wedge the most; as confining layer permeability decreases, the wedge lengthens and the fraction of total discharge exiting through the sinkhole increases. Copyright ?? 2007 IAHS Press.

Extent and severity of groundwater contamination based on hydrochemistry mechanism of sandy tropical coastal aquifer.

Science.gov (United States)

Isa, Noorain Mohd; Aris, Ahmad Zaharin; Sulaiman, Wan Nor Azmin Wan

2012-11-01

Small islands are susceptible to anthropogenic and natural activities, especially in respect of their freshwater supply. The freshwater supply in small islands may be threatened by the encroachment of seawater into freshwater aquifers, usually caused by over pumping. This study focused on the hydrochemistry of the Kapas Island aquifer, which controls the groundwater composition. Groundwater samples were taken from six constructed boreholes for the analysis and measurement of its in-situ and major ions. The experimental results show a positive and significant correlation between Na-Cl (r=0.907; paquifer bedrock. About 76% of collected data (n=108) were found to be in the dissolution process of carbonate minerals. Moreover, the correlation between total CEC and Ca shows a positive and strong relationship (r=0.995; pchemical composition. The output of this research explains the chemical mechanism attributed to the groundwater condition of the Kapas Island aquifer. Copyright © 2012 Elsevier B.V. All rights reserved.

Multiple technologies applied to characterization of the porosity and permeability of the Biscayne aquifer, Florida

Science.gov (United States)

Cunningham, K.J.; Sukop, M.C.

2011-01-01

Research is needed to determine how seepage-control actions planned by the Comprehensive Everglades Restoration Plan (CERP) will affect recharge, groundwater flow, and discharge within the dual-porosity karstic Biscayne aquifer where it extends eastward from the Everglades to Biscayne Bay. A key issue is whether the plan can be accomplished without causing urban flooding in adjacent populated areas and diminishing coastal freshwater flow needed in the restoration of the ecologic systems. Predictive simulation of groundwater flow is a prudent approach to understanding hydrologic change and potential ecologic impacts. A fundamental problem to simulation of karst groundwater flow is how best to represent aquifer heterogeneity. Currently, U.S. Geological Survey (USGS) researchers and academic partners are applying multiple innovative technologies to characterize the spatial distribution of porosity and permeability within the Biscayne aquifer.

Differences between LCA for analysis and LCA for policy : A case study on the consequences of allocation choices in bio-energy policies

NARCIS (Netherlands)

Wardenaar, T.; Van Ruijven, T.W.J.; Beltran, A.M.; Vad, K.; Guinee, J.; Heijungs, R.

2012-01-01

Purpose - The increasing concern for adverse effects of climate change has spurred the search for alternatives for conventional energy sources. Life cycle assessment (LCA) has increasingly been used to assess the potential of these alternatives to reduce greenhouse gas emissions. The popularity of

Differences between LCA for analysis and LCA for policy : A case study on the consequences of allocation choices in bio-energy policies

NARCIS (Netherlands)

Wardenaar, Tjerk; Van Ruijven, Theo; Beltran, Angelica Mendoza; Vad, Kathrine; Guinée, Jeroen B.; Heijungs, Reinout

Purpose: The increasing concern for adverse effects of climate change has spurred the search for alternatives for conventional energy sources. Life cycle assessment (LCA) has increasingly been used to assess the potential of these alternatives to reduce greenhouse gas emissions. The popularity of

From LCC to LCA Using a Hybrid Input Output Model – A Maritime Case Study

DEFF Research Database (Denmark)

Kjær, Louise Laumann; Pagoropoulos, Aris; Hauschild, Michael Zwicky

2015-01-01

As companies try to embrace life cycle thinking, Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) have proven to be powerful tools. In this paper, an Environmental Input-Output model is used for analysis as it enables an LCA using the same economic input data as LCC. This approach helps...

Application of Life Cycle Assessment (LCA) in Sugar Industries

Science.gov (United States)

Astuti, Arieyanti Dwi; Astuti, Rahayu Siwi Dwi; Hadiyanto, Hadiyanto

2018-02-01

Sugar is one of the main commodities that are needed for human life. The demand of sugar is very high with the trend increase from year to year. This condition makes the sugar industry become a leading industry that must be maintained sustainability. The sustainability of the sugar industry is influenced by the use of energy and natural resources and the resulting environmental impacts. Therefore, an effort is needed to analyze the environmental aspects and potential environmental impacts resulting from a product (sugar), by using Life Cycle Assessment (LCA). LCA is a very important tool for the analysis of a process/system from its cradle to grave. This technique is very useful in the estimation of energy usage and environmental load of a product/system. This paper aims to describe the main elements of sugar industries using Life Cycle Assessment.

Identification of the mechanisms and origin of salinization of groundwaters in coastal aquifers by means of isotopic techniques; Identificacion de los mecanismos y del orgien de la salinizacion del agua subterranea en acuiferos costeros mdiante tecnicas isotopicas

Energy Technology Data Exchange (ETDEWEB)

Araguas, L. J.; Quejido, A. J.

2007-07-01

To study the origin of salinity and the mechanisms operating in coastal aquifers, a set of tools is available to determine the essential aspects of the hydrogeological behaviour of the system. these tools are based on the integrated use of hydrochemical parameters (major constituents and trace elements) and isotopic parameters (oxygen, hydrogen, sulfur, carbon, strontium and boron). In addition to the active intrusion of seawater, salinization in coastal areas may be influenced by various human activities that accelerate the degradation of water quality, such as concentrated pumping, intensive farming techniques with return of irrigation water, or reuse of urban and industrial waste water. Characterization of the dominant processes and mechanisms is required for suitable management of the resource and implementation of corrective measures. (Author)

An assessment of subsurface contamination of an urban coastal aquifer due to oil spill.

Science.gov (United States)

Nambi, Indumathi M; Rajasekhar, Bokam; Loganathan, Vijay; RaviKrishna, R

2017-04-01

Incidences of leakages of chemicals from underground oil storage tanks or oil-carrying pipelines have posed huge threat to the coastal aquifers around the world. One such leak was recently identified and notified by the people of Tondiarpet, Chennai, India. The assessment of the contamination level was done by obtaining electrical resistivity maps of the subsurface, drilling of 20 new borewells for soil and water analysis, and testing the water quality of 30 existing borewells. Samples were collected from the borewells, and observations were made that included parameters such as odor, moisture, contamination characteristics, lithology, groundwater level, thickness of the free product that are used to demarcate the extent of soil, and water contamination. Furthermore, a multigas detector was used to detect hydrocarbon presence as soil vapor. Moreover, to capture the transport of dissolved hydrocarbons, 10 samples were collected in the periphery of the study area and were analyzed for the presence of petroleum hydrocarbon and polyaromatic hydrocarbon. Analysis of the data indicated the presence of free-phase hydrocarbon in soil and groundwater close to the junction of Thiruvottiyur high (TH) road (TH) and Varadaja Perumal Koil (VPK) street. Although the contaminant plume is confined to a limited area, it has spread more to the southern and eastern side of the pipeline possibly due to continuous abstraction of groundwater by residential apartments. After cutting a trench along the VPK street and plotting of the plume delineation map, observations indicated that the source of the hydrocarbon leak is present in VPK street close to TH road. A multipronged strategy was suggested targeting the remediation of oil in various phases.

SRP baseline hydrogeologic investigation: Aquifer characterization

Energy Technology Data Exchange (ETDEWEB)

Strom, R.N.; Kaback, D.S.

1992-03-31

An investigation of the mineralogy and chemistry of the principal hydrogeologic units and the geochemistry of the water in the principal aquifers at Savannah River Site (SRS) was undertaken as part of the Baseline Hydrogeologic Investigation. This investigation was conducted to provide background data for future site studies and reports and to provide a site-wide interpretation of the geology and geochemistry of the Coastal Plain Hydrostratigraphic province. Ground water samples were analyzed for major cations and anions, minor and trace elements, gross alpha and beta, tritium, stable isotopes of hydrogen, oxygen, and carbon, and carbon-14. Sediments from the well borings were analyzed for mineralogy and major and minor elements.

The role of dunes in contrasting saltwater intrusion in coastal areas; a case study in the southern Po Plain Adriatic coast (Ravenna, Northern Italy)

Science.gov (United States)

Marconi, V.; Antonellini, M.; Balugani, E.; Minchio, A.; Gabbianelli, G.

2009-04-01

Due to climate changes and to anthropogenic interventions, saltwater intrusion is affecting the aquifers and the surface water of the Po plain along the Adriatic coast. During the last decade, we recognized in this area a pattern of climate change: precipitations are less frequent and the yearly amount of rain is concentrated in a few strong storm events. This pattern results in an increase of gales strength during the winter, which causes shoreline retreat and an erosion of the coastal dunes. The coastal part of the Po plain consists of a low-lying and mechanically-drained farmland further from the sea and of a narrow belt of dunes and pine forests in the backshore area. The wide sandy beaches are now retreating and the dune system (only a few meters in height) is almoust destroyed, because of tourism development and of disaggregated rivers and shorelines management. A still active dune system is preserved in our study area, a coastal plain included between the Fiumi Uniti and Bevano rivers near the city of Ravenna. As a result of an intensive exploitation of coastal aquifers for agricultural, industrial, and civil uses, both the phreatic aquifer and the surface waters have been contaminated by seawater. Despite its value for the natural ecosystem and the agricultural soil, the phreatic aquifer is not considered of interest by the regional authorities responsible for water management. A detailed hydrogeological survey was performed by our research group during the Summer 2008 within the framework of the CIRCLE-ERANET project WATERKNOW on the effects of climate change on the mediterranean catchments. In this survey 29 auger holes with an average spacing of 350 m where drilled with the objective of determining the top groundwater quality in the coastal aquifer. At the same time, we measured the chemical and physical parameters of the surface waters. The data collected in the field show that a fresh groundwater lens is still present in the aquifer of the backshore

Sedimentological techniques applied to the hydrology of the Atlantic coastal plain in South Carolina and Georgia near the Savannah River Site

International Nuclear Information System (INIS)

Falls, F.W.; Baum, J.S.; Edwards, L.E.

1994-01-01

Potential for migration of contaminants in ground water under the Savannah River from South Carolina into Georgia near the US Department of Energy (DOE) Savannah River Site (SRS). The SRS is located in the inner Atlantic Coastal Plain of South Carolina and is underlain by 200 to more than 300 meters of permeable, unconsolidated to poorly consolidated sediments of Cretaceous and Tertiary age. The US Geological Survey, in cooperation with the US Department of Energy and the Georgia Department of Natural Resources, is evaluating ground-water flow through the Coastal Plain sediments in the area. Preliminary hydrologic studies conducted to provide the data needed for digital modeling of the ground-water flow system identified the need for more extensive investigation into the influence of the geologic complexities on that flow system. The Coastal Plain physiographic province in South Carolina and Georgia is comprised of a complex wedge of fluvial, deltaic, and marine sedimentary deposits locally modified by faulting. Several techniques commonly used in petroleum basin analysis (sequence stratigraphy, biostratigraphy, detailed core description, and geophysical well log analysis), were used together with water-level measurements, aquifer-test data, and geochemical data to identify six regional aquifers. Hydraulic conductivity distribution maps within each of these aquifers were constructed using textural analysis of core materials, aquifer test data, and depositional system reconstruction. Sedimentological techniques were used to improve understanding of the depositional system and the ground-water flow system dynamics, and to help focus research in areas where additional hydrologic, geologic, and aquifer-test data are needed

LCA applied to elucidate opportunities for biogas from wastewaters in Colombia.

Science.gov (United States)

Meneses-Jácome, A; Osorio-Molina, A; Parra-Saldívar, R; Gallego-Suárez, D; Velásquez-Arredondo, H I; Ruiz-Colorado, A A

2015-01-01

Biogas produced in municipal and industrial wastewater treatment facilities (BWWF) is a resource wasted in several socio-economic contexts. BWWF-based projects are compared against energy projects using conventional electricity or natural gas (NG), following strict economic considerations that usually tip the balance in favour of conventional energy supply. This is because the economic gain associated with the environmental benefits of using small biogas sources like BWWF does not overcome the technical and financial effort required in these types of project. This paper shows a broader application of life cycle assessment (LCA) methodology to explore opportunities for positive (or effective) utilization of BWWF in the Colombian context. LCA has been used to evaluate the supply-chain of NG which is the direct competitor of BWWF, in three different Colombian regions, in order to identify those where higher NG environmental impacts offer increased environmental added-value to BWWF use. LCA was also applied to study two BWWF valorization scenarios in the poultry processing industry. It shows how valorization options for BWWF are more realistic and effective when specific-regional loads are applied to the environmental assessment of NG supply-chain and BWWF valorization.

Assessing the efficiency of a coastal Managed Aquifer Recharge (MAR) system in Cyprus.

Science.gov (United States)

Tzoraki, Ourania; Dokou, Zoi; Christodoulou, George; Gaganis, Petros; Karatzas, George

2018-06-01

Managed Aquifer Recharge (MAR) is becoming an attractive water management option, with more than 223 sites operating in European countries. The quality of the produced water, available for drinking or irrigation processes is strongly depended on the aquifer's hydrogeochemical characteristics and on the MAR system design and operation. The objective of this project is the assessment of the operation efficiency of a MAR system in Cyprus. The coupling of alternative methodologies is used such as water quality monitoring, micro-scale sediment sorption experiments, simulation of groundwater flow and phosphate and copper transport in the subsurface using the FEFLOW model and evaluation of the observed change in the chemical composition of water due to mixing using the geochemical model PHREEQC. The above methodology is tested in the Ezousa MAR project in Cyprus, where treated effluent from the Paphos Waste Water Treatment Plant, is recharged into the aquifer through five sets of artificial ponds along the riverbed. Additionally, groundwater is pumped for irrigation purposes from wells located nearby. A slight attenuation of nutrients is observed, whereas copper in groundwater is overcoming the EPA standards. The FEFLOW simulations reveal no effective mixing in some intermediate infiltration ponds, which is validated by the inverse modeling simulation of the PHREEQC model. Based on the results, better control of the infiltration capacity of some of the ponds and increased travel times are some suggestions that could improve the efficiency of the system. Copyright © 2018 Elsevier B.V. All rights reserved.

poLCA: An R Package for Polytomous Variable Latent Class Analysis

Directory of Open Access Journals (Sweden)

Drew A. Linzer

2011-08-01

Full Text Available poLCA is a software package for the estimation of latent class and latent class regression models for polytomous outcome variables, implemented in the R statistical computing environment. Both models can be called using a single simple command line. The basic latent class model is a finite mixture model in which the component distributions are assumed to be multi-way cross-classification tables with all variables mutually independent. The latent class regression model further enables the researcher to estimate the effects of covariates on predicting latent class membership. poLCA uses expectation-maximization and Newton-Raphson algorithms to find maximum likelihood estimates of the model parameters.

Characteristics and factors of groundwater contamination in Asian coastal megacities

Science.gov (United States)

Saito, M.; Onodera, S. I.; Jin, G.; Shimizu, Y.; Admajaya, F. T.

2017-12-01

For the sustainable use of groundwater resources for the future, it is important to conserve its quality as well as quantity. Especially in the developing megacities, land subsidence and groundwater pollution by several contaminants (e.g. nitrogen, trace metals and organic pollutants etc.) is one of a critical environmental problems, because of the intensive extraction of groundwater and huge amount of contaminant load derived from domestic wastewater as well as agricultural and industrial wastewater. However, the process of groundwater degradation, including depletion and contamination with urbanization, has not been examined well in the previous studies. In the present study, we aim to confirm the characteristics and factors of groundwater contamination in coastal Asian megacities such as Osaka and Jakarta. In Osaka, groundwater was used as a water resource during the period of rapid population increase before 1970, and consequently groundwater resources have been degraded. Hydraulic potential of groundwater has been recovered after the regulation for abstraction. However, it is still below sea level in the deeper aquifer (>20 m) of some regions, and higher Cl-, NH4+-N and PO43-P concentrations were detected in these regions. The results also suggest that shallower aquifer (>10 m) is influenced by infiltration of sewage to groundwater. In the Jakarta metropolitan area, current hydraulic potential is below sea level in because of prior excess abstraction of groundwater. As a result, the direction of groundwater flow is now downward in the coastal area. The distribution of Cl- and Mn concentration in groundwater suggests that the decline in hydraulic potential has caused the intrusion of seawater and shallow groundwater into deep groundwater. It implies an accumulation of contaminants in deep aquifers. On the other hands, NO3-N in groundwater is suggested to be attenuated by the processes of denitrification and dilution in the coastal area.

Forecasting monthly groundwater level fluctuations in coastal aquifers using hybrid Wavelet packet–Support vector regression

Directory of Open Access Journals (Sweden)

N. Sujay Raghavendra

2015-12-01

Full Text Available This research demonstrates the state-of-the-art capability of Wavelet packet analysis in improving the forecasting efficiency of Support vector regression (SVR through the development of a novel hybrid Wavelet packet–Support vector regression (WP–SVR model for forecasting monthly groundwater level fluctuations observed in three shallow unconfined coastal aquifers. The Sequential Minimal Optimization Algorithm-based SVR model is also employed for comparative study with WP–SVR model. The input variables used for modeling were monthly time series of total rainfall, average temperature, mean tide level, and past groundwater level observations recorded during the period 1996–2006 at three observation wells located near Mangalore, India. The Radial Basis function is employed as a kernel function during SVR modeling. Model parameters are calibrated using the first seven years of data, and the remaining three years data are used for model validation using various input combinations. The performance of both the SVR and WP–SVR models is assessed using different statistical indices. From the comparative result analysis of the developed models, it can be seen that WP–SVR model outperforms the classic SVR model in predicting groundwater levels at all the three well locations (e.g. NRMSE(WP–SVR = 7.14, NRMSE(SVR = 12.27; NSE(WP–SVR = 0.91, NSE(SVR = 0.8 during the test phase with respect to well location at Surathkal. Therefore, using the WP–SVR model is highly acceptable for modeling and forecasting of groundwater level fluctuations.

Field and model investigations of freshwater lenses in coastal aquifers

NARCIS (Netherlands)

Pauw, P.S.

2015-01-01

A major problem of sustaining freshwater supply from freshwater lens is the invasion of saline groundwater into a fresh groundwater body. In many coastal areas saltwater intrusion has led to well closure and reduced freshwater supply. Furthermore, in the future saltwater intrusion is expected to

Geophysical detection of marine intrusions in Black Sea coastal areas (Romania) using VES and ERT data

OpenAIRE

CHITEA, Florina; GEORGESCU, Paul; IOANE, Dumitru

2011-01-01

Abstract. Communities living in coastal areas depend in a great extent on the fresh water resources exploited from aquifers which are usually in a natural hydrodynamic equilibrium with the sea water. The contamination of fresh water with marine saltwater determines a significant increase in the aquifers electric conductivity, allowing an efficient application of resistivity methods in detecting and monitoring the marine intrusions. We present case studies from Romania (Costinesti and Vama Vec...

LCA as an environmental technology development performance indicator of engineered nano-materials and their application in polymers

DEFF Research Database (Denmark)

Miseljic, Mirko; Olsen, Stig Irving; Hauschild, Michael Zwicky

project is aimed to be holistic and thereby include the entire life cycle of the nano‐polymer products and not be like the current frequently applied nano‐material LCA case study approaches where the life cycle is reduced and system boundaries substantially limited. In order to perform accurate......Engineered nano‐material (ENM) application in products has in recent years developed to an important market segment but with rising environmental concerns, as the environmental life cycle impacts, especially toxicity of nanoparticles, are not assessed. Life cycle assessment (LCA) is a holistic tool...... to the conventional ways of attaining these in the polymer product industry. To assure environmental sustainability LCA will be performed within the MINANO project and more precisely comparing the new ENM technology and the conventional technology approach to attain the same functionalities. The LCA in the MINANO...

Challenges in Projecting Sea Level Rise impacts on the Coastal Environment of South Florida (Invited)

Science.gov (United States)

Obeysekera, J.; Park, J.; Irizarry-Ortiz, M. M.; Barnes, J. A.; Trimble, P.; Said, W.

2010-12-01

Due to flat topography, a highly transmissive groundwater aquifer, and a growing population with the associated infrastructure, South Florida’s coastal environment is one of the most vulnerable areas to sea level rise. Current projections of sea level rise and the associated storm surges will have direct impacts on coastal beaches and infrastructure, flood protection, freshwater aquifers, and both the isolated and regional wetlands. Uncertainties in current projections have made it difficult for regional and local governments to develop adaptation strategies as such measures will depend heavily on the temporal and spatial patterns of sea level rise in the coming decades. We demonstrate the vulnerability of both the built and natural environments of the coastal region and present the current efforts to understand and predict the sea level rise estimate that management agencies could employ in planning of adaptation strategies. In particular, the potential vulnerabilities of the flood control system as well as the threat to the water supply wellfields in the coastal belt will be presented. In an effort to understand the historical variability of sea level rise, we present linkages to natural phenomena such as Atlantic Multi-Decadal Oscillation, and the analytical methods we have developed to provide probabilistic projections of both mean sea level rise and the extremes.

Optimal utilization of waste-to-energy in an LCA perspective

DEFF Research Database (Denmark)

Fruergaard, Thilde; Astrup, Thomas

2011-01-01

Energy production from two types of municipal solid waste was evaluated using life cycle assessment (LCA): (1) mixed high calorific waste suitable for production of solid recovered fuels (SRF) and (2) source separated organic waste. For SRF, co-combustion was compared with mass burn incineration....... For organic waste, anaerobic digestion (AD) was compared with mass burn incineration. In the case of mass burn incineration, incineration with and without energy recovery was modelled. Biogas produced from anaerobic digestion was evaluated for use both as transportation fuel and for heat and power production....... All relevant consequences for energy and resource consumptions, emissions to air, water and soil, upstream processes and downstream processes were included in the LCA. Energy substitutions were considered with respect to two different energy systems: a present-day Danish system based on fossil fuels...

Isotope and Hydrochemical Study of Seawater Intrusion into the Aquifers of a Coastal Zone in Cuba

Energy Technology Data Exchange (ETDEWEB)

Dapena, C.; Panarello, H. O.; Ducos, E. I.; Marban, L. [Instituto de Geocronologia y Geologia Isotopica (INGEIS, CONICET -UBA), Buenos Aires (Argentina); Peralta Vital, J. L.; Gil Castillo, R.; Leyva Bombuse, D. [Centro de Proteccion e Higiene de las Radiaciones (CPHR), La Habana (Cuba); Valdez, L. [Empresa de Investigaciones y Proyectos Hidraulicos Habana, La Habana (Cuba); Olivera Acosta, J. [Instituto de Geofisica y Astronomia. La Habana (Cuba)

2013-07-15

The Artemisa-Quivican Basin is located in the southern sector of the province of Havana, Cuba. This basin contains the most important aquifer of Havana province. It has a length of nearly 120 km and is 25 km in width. Recharge depends on the precipitation regime and rain infiltrates in a considerable proportion due to the intense development of karstic features. This aquifer is used for water supply to population, industry, and irrigation and is affected by over-exploitation and risk of contamination by saline sea intrusion. The main objective of this study is the isotope and chemical characterization of the aquifer and the delimitation of the area influenced by saline intrusion. Groundwater and river water are of the calcium bicarbonate type except those with evidence of mixture with saline water. Groundwater exhibits a variable proportion of mixture with seawater, indicating the presence of the saline intrusion. (author)

Gaining the necessary geologic, hydrologic, and geochemical understanding for additional brackish groundwater development, coastal San Diego, California, USA

Science.gov (United States)

Danskin, Wesley R.

2012-01-01

Local water agencies and the United States Geological Survey are using a combination of techniques to better understand the scant freshwater resources and the much more abundant brackish resources in coastal San Diego, California, USA. Techniques include installation of multiple-depth monitoring well sites; geologic and paleontological analysis of drill cuttings; geophysical logging to identify formations and possible seawater intrusion; sampling of pore-water obtained from cores; analysis of chemical constituents including trace elements and isotopes; and use of scoping models including a three-dimensional geologic framework model, rainfall-runoff model, regional groundwater flow model, and coastal density-dependent groundwater flow model. Results show that most fresh groundwater was recharged during the last glacial period and that the coastal aquifer has had recurring intrusions of fresh and saline water. These intrusions disguise the source, flowpaths, and history of ground water near the coast. The flow system includes a freshwater lens resting on brackish water; a 100-meter-thick flowtube of freshwater discharging under brackish estuarine water and above highly saline water; and broad areas of fine-grained coastal sediment filled with fairly uniform brackish water. Stable isotopes of hydrogen and oxygen indicate the recharged water flows through many kilometers of fractured crystalline rock before entering the narrow coastal aquifer.

The applicability of LCA to evaluate the key environmental challenges in food supply chains

DEFF Research Database (Denmark)

Aronsson, Anna K.S.; Landquist, Birgit; Esturo, Aintzane

2014-01-01

System analysis was performed to gain an overview of key environmental challenges and pinpoint hotspots causing environmental impacts in three European food supply chains. An overview was obtained based on a review on LCA studies for beef, dairy, orange juice and aquaculture food supply chains....... Similarities of the main environmental impacts were identified to rationalize and justify the selection of key performance indicators chosen for a simplified web based LCA tool developed within the EC funded project SENSE (FP7). Life Cycle Assessment methodology covered many of the key challenges identified...... but will not be sufficient to address all environmental impacts generated from the food supply chains. Especially for aquaculture impacts that are not taken into account with LCA are i.e. nutrient and organic matter releases, impacts associated with feed provision, diseases introduction, escapes, and changed usage...

Salinization of aquifers at the regional scale by marine transgression: Time scales and processes

Science.gov (United States)

Armandine Les Landes, A.; Davy, P.; Aquilina, L.

2014-12-01

Saline fluids with moderate concentrations have been sampled and reported in the Armorican basement at the regional scale (northwestern France). The horizontal and vertical distributions of high chloride concentrations (60-1400mg/L) at the regional scale support the marine origin and provide constraints on the age of these saline fluids. The current distribution of fresh and "saline" groundwater at depth is the result mostly of processes occurring at geological timescales - seawater intrusion processes followed by fresh groundwater flushing -, and only slightly of recent anthropogenic activities. In this study, we focus on seawater intrusion mechanisms in continental aquifers. We argue that one of the most efficient processes in macrotidal environments is the gravity-driven downconing instability below coastal salinized rivers. 2-D numerical experiments have been used to quantify this process according to four main parameter types: (1) the groundwater system permeability, (2) the salinity degree of the river, (3) the river width and slope, and (4) the tidal amplitude. A general expression of the salinity inflow rates have been derived, which has been used to estimate groundwater salinization rates in Brittany, given the geomorphological and environmental characteristics (drainage basin area, river widths and slopes, tidal range, aquifer permeability). We found that downconing below coastal rivers entail very high saline rates, indicating that this process play a major role in the salinization of regional aquifers. This is also likely to be an issue in the context of climate change, where sea-level rise is expected.

Introduction to Part III: Application of LCA in Practice

DEFF Research Database (Denmark)

Rosenbaum, Ralph K.

2018-01-01

While Part II of this book presents the theoretical foundation and methodology of LCA, Part III is dedicated to a comprehensive discussion of how this methodology has been adapted and applied in practice. The chapters of Part III provide an easily readable and accessible introduction to different...

Analysis and Assessment of Environmental Load of Vending Machines by a LCA Method, and Eco-Improvement Effect

Science.gov (United States)

Kimura, Yukio; Sadamichi, Yucho; Maruyama, Naoki; Kato, Seizo

These days the environmental impact due to vending machines'(VM) diffusion has greatly been discussed. This paper describes the numerical evaluation of the environmental impact by using the LCA (Life Cycle Assessment) scheme and then proposes eco-improvements' strategy toward environmentally conscious products(ECP). A new objective and universal consolidated method for the LCA-evaluation, so-called LCA-NETS(Numerical Eco-load Standardization ) developed by the authors is applied to the present issue. As a result, the environmental loads at the 5years' operation and the material procurement stages are found to dominate others over the life cycle. Further eco-improvement is realized by following the order of the LCA-NETS magnitude; namely, energy saving, materials reducing, parts' re-using, and replacing with low environmental load material. Above all, parts' re-using is specially recommendable for significant reduction of the environmental loads toward ECP.

Panorama 2013 - Using LCA in selecting technologies

International Nuclear Information System (INIS)

Collet, Pierre

2012-12-01

Our society is increasingly concerned with safeguarding the environment. By assessing the impact that the manufacture of a product or the delivery of a service can have on the environment, Life-Cycle Assessment (LCA) can be used to identify key sources of pollution and possible ways of mitigating against it. The ways in which this tool can be used are demonstrated here by various projects which help define innovative energy production systems. (author)

Pond-aquifer flow and water availability in the vicinity of two coastal area seepage ponds, Glynn and Bulloch Counties, Georgia

Science.gov (United States)

Clarke, John S.; Rumman, Malek Abu

2005-01-01

Pond-aquifer flow and water availability at excavated seepage pond sites in Glynn County and in southern Bulloch County, Georgia, were evaluated to determine their potential as sources of water supply for irrigation. Excavated seepage ponds derive water primarily from ground water seeping into the pond, in a manner similar to a dug well completed in a surficial aquifer. The availability of water from seepage ponds is controlled by the permeability of surficial deposits, the amount of precipitation recharging the ground-water system, and the volume of water stored in the pond. The viability of seepage ponds as supplies for irrigation is limited by low seepage rates and high dependence on climatic conditions. Ponds will not refill unless there is adequate precipitation to recharge the surficial aquifer, which subsequently drains (seeps) into the pond. Ground-water seepage was estimated using a water-budget approach that utilized on-site climatic and hydrologic measurements, computing pond-volume changes during pond pumping tests, and by digital simulation using steady-state and transient ground-water flow models. From August 1999 to May 2000, the Glynn County pond was mostly losing water (as indicated by negative net seepage); whereas from October 2000 to June 2001, the Bulloch County pond was mostly gaining water. At both sites, most ground-water seepage entered the pond following major rainfall events that provided recharge to the surficial aquifer. Net ground-water seepage, estimated using water-budget analysis and simulation, ranged from -11.5 to 15 gallons per minute (gal/min) at the Glynn County pond site and from -55 to 31 gal/min at the Bulloch County pond site. Simulated values during pumping tests indicate that groundwater seepage to both ponds increases with decreased pond stage. At the Glynn County pond, simulated net ground-water seepage varied between 7.8 gal/min at the beginning of the test (high pond stage and low hydraulic gradient) and 103 gal

LCA single score analysis of man-made cellulose fibres

NARCIS (Netherlands)

Shen, L.; Patel, M.K.

2010-01-01

In this study, the LCA report “Life Cycle assessment of man-made cellulose fibres” [3] is extended to the single score analysis in order to provide an additional basis for decision making. The single score analysis covers 9 to 11 environmental impact categories. Three single score methods (Single

Impact Assessment of Abiotic Resources in LCA: Quantitative Comparison of Selected Characterization Models

DEFF Research Database (Denmark)

Rørbech, Jakob Thaysen; Vadenbo, Carl; Hellweg, Stefanie

2014-01-01

Resources have received significant attention in recent years resulting in development of a wide range of resource depletion indicators within life cycle assessment (LCA). Understanding the differences in assessment principles used to derive these indicators and the effects on the impact assessment...... results is critical for indicator selection and interpretation of the results. Eleven resource depletion methods were evaluated quantitatively with respect to resource coverage, characterization factors (CF), impact contributions from individual resources, and total impact scores. We included 2247...... groups, according to method focus and modeling approach, to aid method selection within LCA....

Integrating LCA and EHS expertise in the assessment of nanoparticles

DEFF Research Database (Denmark)

Olsen, Stig Irving; Hankin, Steve; Chaudry, Qasim

DTU with their expertise in LCA have joined forces with IOM in two nanotechnology-related projects, one of which additionally involves and is lead by FERA. The first project, Nancore, includes the evaluation of health risks and environmental impacts over the life cycle concurrently with the devel......DTU with their expertise in LCA have joined forces with IOM in two nanotechnology-related projects, one of which additionally involves and is lead by FERA. The first project, Nancore, includes the evaluation of health risks and environmental impacts over the life cycle concurrently...... the overall environmental impacts of the technology. Through the concurrent assessments, the strengths of the two tools are combined to provide a more qualified assessment of both the health and safety aspects and the life cycle impacts. The overall aim of the second project, sponsored by Defra...

Challenges in LCA modelling of multiple loops for aluminium cans

DEFF Research Database (Denmark)

Niero, Monia; Olsen, Stig Irving

considered the case of closed-loop recycling for aluminium cans, where body and lid are different alloys, and discussed the abovementioned challenge. The Life Cycle Inventory (LCI) modelling of aluminium processes is traditionally based on a pure aluminium flow, therefore neglecting the presence of alloying...... elements. We included the effect of alloying elements on the LCA modelling of aluminium can recycling. First, we performed a mass balance of the main alloying elements (Mn, Fe, Si, Cu) in aluminium can recycling at increasing levels of recycling rate. The analysis distinguished between different aluminium...... packaging scrap sources (i.e. used beverage can and mixed aluminium packaging) to understand the limiting factors for multiple loop aluminium can recycling. Secondly, we performed a comparative LCA of aluminium can production and recycling in multiple loops considering the two aluminium packaging scrap...

Production of recyclates – compared with virgin Plastics – a LCA Study

Directory of Open Access Journals (Sweden)

Storm Birgit Kjærside

2017-01-01

Full Text Available Plastix A/S is a Danish cleantech company transforming discarded fishing trawls and nets into valuable green raw materials. Plastix– technology and processes solve a maritime waste problem and contribute to a more circular green economy and reduce landfilling, marine pollution, CO2 emissions and especially loss of valuable resources. Plastix– recycling technology enables recovery of discarded fishing trawls and nets via mechanical and thermal processes transforming the waste into valuable recycles which can be converted into plastic products replacing virgin raw materials. The performance has been proved through a Life Cycle Assessment (LCA study. The results from the LCA study are compared with the production of virgin materials. The results of the LCA show that especially the carbon footprint is remarkable better for Oceanix than for virgin plastics. Oceanix HDPE is 5 times better than virgin HDPE, when talking about the carbon foot print, and the results for Oceanix PP and Oceanix PA6 are 5 times and 20 times better compared with virgin PP and PA6. Also other environmental indicators are better for Oceanix compared with virgin plastics.

Sources of water to wells in updip areas of the Wenonah-Mount Laurel aquifer, Gloucester and Camden Counties, New Jersey

Science.gov (United States)

Watt, Martha K.; Voronin, Lois M.

2006-01-01

Since 1996, when the New Jersey Department of Environmental Protection (NJDEP) restricted ground-water withdrawals from the Potomac-Raritan-Magothy aquifer system in the southern New Jersey Coastal Plain as a result of excessive drawdown, Coastal Plain communities have been interested in developing alternate sources of water supply for their residents. The use of ground water from areas near the updip parts of the overlying confined aquifers where withdrawals are not restricted is being considered to meet the demand for drinking water. Concerns have arisen, however, regarding the potential effects of increased withdrawals from these areas on ground-water flow to streams and wetlands as well as to the deeper, confined parts of the aquifers. Therefore, the U.S. Geological Survey, in cooperation with the NJDEP, conducted a study to investigate the sources of water to currently inactive wells in the updip part of the Wenonah-Mount Laurel aquifer in Gloucester and Camden Counties, New Jersey. Of particular interest is whether the primary source of the increased withdrawals is likely to be the aquifer outcrop or the downdip, confined part of the aquifer. The outcrop of the Wenonah-Mount Laurel aquifer covers nearly 8 mi2 (square miles), or about 46 percent of Deptford Township's 17.56-mi2 area. The Deptford Township Municipal Utilities Authority owns six currently (2005) inactive wells in the Wenonah-Mount Laurel aquifer at the southeastern boundary of Deptford Township, 1.25 mi (miles) from the outcrop. For the purposes of this study, an existing ground-water-flow model of the New Jersey Coastal Plain aquifers was used to simulate ground-water-flow conditions in Gloucester and Camden Counties in 1998. Two alternative withdrawal scenarios were superimposed on the results of the 1998 simulation. In the first (the 'full-allocation' scenario), full-allocation withdrawal rates established by the NJDEP were applied to 45 existing wells in the Deptford Township area. In the

Intervenção da fisioterapia após ligamentoplastia do LCA

OpenAIRE

Bonança, Daniela

2014-01-01

RESUMO: Objectivo: Este estudo teve por objectivo descrever a prática clínica e os resultados da intervenção da fisioterapia, às 6, 12 e 24 semanas, em indivíduos após ligamentoplastia do LCA. Introdução: O sucesso da ligamentoplastia do LCA está directamente relacionado com a reabilitação após a realização da mesma, permitindo ao utente o retorno a um estilo de vida activo. Apesar de se saber que um programa de reabilitação estruturado e baseado na evidência tem um papel fulcral nos resul...

Review of LCA studies of solid waste management systems – Part II: Methodological guidance for a better practice

International Nuclear Information System (INIS)

Laurent, Alexis; Clavreul, Julie; Bernstad, Anna; Bakas, Ioannis; Niero, Monia; Gentil, Emmanuel; Christensen, Thomas H.; Hauschild, Michael Z.

2014-01-01

Highlights: • We perform a critical review of 222 LCA studies of solid waste management systems. • We analyse the past LCA practice against the ISO standard and ILCD Handbook guidance. • Malpractices exist in many methodological aspects with large variations among studies. • Many of these aspects are important for the reliability of the results. • We provide detailed recommendations to practitioners of waste management LCAs. - Abstract: Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements and the ILCD Handbook guidelines for each major step within the goal definition, scope definition, inventory analysis, impact assessment, and interpretation phases of the methodology. Results show that malpractices exist in several aspects of the LCA with large differences across studies. Examples are a frequent neglect of the goal definition, a frequent lack of transparency and precision in the definition of the scope of the study, e.g. an unclear delimitation of the system boundaries, a truncated impact coverage, difficulties in capturing influential local specificities such as representative waste compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs

Review of LCA studies of solid waste management systems – Part II: Methodological guidance for a better practice

Energy Technology Data Exchange (ETDEWEB)

Laurent, Alexis, E-mail: alau@dtu.dk [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Clavreul, Julie [Residual Resources Engineering, Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Bernstad, Anna [Water and Environmental Engineering, Department of Chemical Engineering, Lund University, 221 00 Lund (Sweden); Bakas, Ioannis [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Niero, Monia [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); ECO – Ecosystems and Environmental Sustainability, Department of Chemical and Biochemical Engineering, Technical University of Denmark, 4000 Roskilde (Denmark); Gentil, Emmanuel [Copenhagen Resource Institute, 1215 Copenhagen K (Denmark); Christensen, Thomas H. [Residual Resources Engineering, Department of Environmental Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark); Hauschild, Michael Z. [Division for Quantitative Sustainability Assessment, Department of Management Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

2014-03-01

Highlights: • We perform a critical review of 222 LCA studies of solid waste management systems. • We analyse the past LCA practice against the ISO standard and ILCD Handbook guidance. • Malpractices exist in many methodological aspects with large variations among studies. • Many of these aspects are important for the reliability of the results. • We provide detailed recommendations to practitioners of waste management LCAs. - Abstract: Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements and the ILCD Handbook guidelines for each major step within the goal definition, scope definition, inventory analysis, impact assessment, and interpretation phases of the methodology. Results show that malpractices exist in several aspects of the LCA with large differences across studies. Examples are a frequent neglect of the goal definition, a frequent lack of transparency and precision in the definition of the scope of the study, e.g. an unclear delimitation of the system boundaries, a truncated impact coverage, difficulties in capturing influential local specificities such as representative waste compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs.

Biogeochemical cycling of arsenic in coastal salinized aquifers: Evidence from sulfur isotope study

International Nuclear Information System (INIS)

Kao, Yu-Hsuan; Wang, Sheng-Wei; Liu, Chen-Wuing; Wang, Pei-Ling; Wang, Chung-Ho; Maji, Sanjoy Kumar

2011-01-01

Arsenic (As) contamination of groundwater, accompanied by critical salinization, occurs in the southwestern coastal area of Taiwan. Statistical analyses and geochemical calculations indicate that a possible source of aqueous arsenic is the reductive dissolution of As-bearing iron oxyhydroxides. There are few reports of the influence of sulfate-sulfide redox cycling on arsenic mobility in brackish groundwater. We evaluated the contribution of sulfate reduction and sulfide re-oxidation on As enrichment using δ 34 S [SO 4 ] and δ 18 O [SO 4 ] sulfur isotopic analyses of groundwater. Fifty-three groundwater samples were divided into groups of high-As content and salinized (Type A), low-As and non-salinized (Type B), and high-As and non-salinized (Type C) groundwaters, based on hydro-geochemical analysis. The relatively high enrichment of 34 S [SO 4 ] and 18 O [SO 4 ] present in Type A, caused by microbial-mediated reduction of sulfate, and high 18 O enrichment factor (ε [SO 4 -H 2 O] ), suggests that sulfur disproportionation is an important process during the reductive dissolution of As-containing iron oxyhydroxides. Limited co-precipitation of ion-sulfide increased the rate of As liberation under anaerobic conditions. In contrast to this, Type B and Type C groundwater samples showed high δ 18 O [SO 4 ] and low δ 34 S [SO 4 ] values under mildly reducing conditions. Base on 18 O mass balance calculations, the oxide sources of sulfate are from infiltrated atmospheric O 2 , caused by additional recharge of dissolved oxygen and sulfide re-oxidation. The anthropogenic influence of extensive pumping also promotes atmospheric oxygen entry into aquifers, altering redox conditions, and increasing the rate of As release into groundwater. - Highlights: → Seawater intrusion and elevated As are the main issues of groundwater in Taiwan. → Sulfur and oxygen isotopes of sulfate were analyzed to evaluate the As mobility. → Reductive dissolution of Fe minerals and

The origin of barium in the Cambrian–Vendian aquifer system, North Estonia

Directory of Open Access Journals (Sweden)

Mokrik, Robert

2009-09-01

Full Text Available Identification of the barium occurrence and its origin is made on the basis of the groundwater chemistry study. High Ba content has been detected in the Cambrian–Vendian aquifer system in the coastal vicinity of the Gulf of Finland in Estonia and St Petersburg. The dissolution of Ba from witherite as the primary source was derived from the analysis of the aqueous solution equilibrium with Ba-related minerals. It is reflected in the chemical composition of groundwater and influenced by the galenite–calcite–fluorite polymetallic mineralization in Vendian sandstones. The dissolution and re-deposition of carbonates and baryte are confirmed by mineral saturation states for an aqueous solution and distribution of other species in the groundwater of the Cambrian–Vendian aquifer system in North Estonia.

Review of LCA studies of solid waste management systems – Part II: Methodological guidance for a better practice

DEFF Research Database (Denmark)

Laurent, Alexis; Clavreul, Julie; Bernstad, Anna

2014-01-01

conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements......Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper...... compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs. © 2013 Elsevier Ltd. All...

Carbonate aquifers

Science.gov (United States)

Cunningham, Kevin J.; Sukop, Michael; Curran, H. Allen

2012-01-01

Only limited hydrogeological research has been conducted using ichnology in carbonate aquifer characterization. Regardless, important applications of ichnology to carbonate aquifer characterization include its use to distinguish and delineate depositional cycles, correlate mappable biogenically altered surfaces, identify zones of preferential groundwater flow and paleogroundwater flow, and better understand the origin of ichnofabric-related karst features. Three case studies, which include Pleistocene carbonate rocks of the Biscayne aquifer in southern Florida and Cretaceous carbonate strata of the Edwards–Trinity aquifer system in central Texas, demonstrate that (1) there can be a strong relation between ichnofabrics and groundwater flow in carbonate aquifers and (2) ichnology can offer a useful methodology for carbonate aquifer characterization. In these examples, zones of extremely permeable, ichnofabric-related macroporosity are mappable stratiform geobodies and as such can be represented in groundwater flow and transport simulations.

How can LCA approaches contribute to improve geo-cycles management

Science.gov (United States)

Carreiras, M.; Ferreira, A. J. D.; Esteves, T. C. J.; Delgado, F.; Andrade, F.; Franco, J.; Pereira, C. D.

2012-04-01

Climate change and land use have become a major challenge for mankind and the natural environment. Greenhouse gas (GHG) emissions released into the atmosphere in ever rapidly growing volumes are most likely to be responsible for this change. Carbon dioxide gas (CO2) is suggested to be the main cause of global warming. Carbon reduction is the key to preventing this, for example, by enhancing energy efficiency and mitigating carbon emissions by means of green energy and adjusting the use of natural resources. Different activities produce distinguish impacts, and each product generates specific impacts on nature. The impact of man activities in the geo-cycles is of paramount importance in what concerns long term sustainability. Nevertheless, the environmental and sustainability impacts of different approaches and techniques of ecosystem management is a difficult question that can be assessed using LCA techniques LCA is a technique to assess environmental impacts associated with all the stages of a product's life from-cradle-to-grave. Based on that, LCA can be effective in supporting the assessment of decision making on complex sustainability issues because it can integrate the diversity of impacts categories guise and it can be adapted to a large variety of contexts. By incorporating quantitative data LCA allows decision makers to include a full range of economic, environmental, social and technical criteria. The integrated framework is configured such that the pros and cons of alternative environmental and energy strategies can be measured in terms of their ability to achieve the overall goals and objectives of the sustainable development, while satisfying the pollution control requirements. Because it is holistic, integrate and dynamic, this approach represents a state of the art tool for enhance the sustainable development of a sector, allowing a more transparent and participated management, a basic instrument for improved competitiveness. This approach may serve

Study of variation in groundwater quality in a coastal aquifer in north-eastern Tunisia using multivariate factor analysis

KAUST Repository

Charfi, Sihem; Zouari, Kamel; Feki, Saber; Mami, Ezeddine

2013-01-01

This work focuses on the Grombalia aquifer which constitutes the main water resource in Northeast Tunisia, Cap Bon Peninsula. The recharge of this aquifer is ensured mainly by direct infiltration of rainwater through permeable layers. Under semi-arid climatic conditions and increasing water demand for irrigation, about 80% of the Grombalia aquifer system shows different vulnerabilities to anthropogenic activities. The total dissolved solids values range from 0.75 to 5.6g/l.Isotopic characterization with stable isotopes (δ2H and δ18O) of Grombalia aquifer system identified geochemistry processes that control water chemistry. In addition, the multivariate statistical technique (Principal Component Analysis) was used to identify the origin, the recharge mode and geochemical processes controlling groundwater quality. The principal reactions responsible for the hydrochemical evolution in the Grombalia groundwater fall into three categories: (1) denitrification process; (2) dissolution of salts; and (3) irrigation return flow process. Tritium data in groundwater from the study area suggest the existence of pre1950 and post1960 recharge. © 2012 Elsevier Ltd and INQUA.

Study of variation in groundwater quality in a coastal aquifer in north-eastern Tunisia using multivariate factor analysis

KAUST Repository

Charfi, Sihem

2013-07-01

This work focuses on the Grombalia aquifer which constitutes the main water resource in Northeast Tunisia, Cap Bon Peninsula. The recharge of this aquifer is ensured mainly by direct infiltration of rainwater through permeable layers. Under semi-arid climatic conditions and increasing water demand for irrigation, about 80% of the Grombalia aquifer system shows different vulnerabilities to anthropogenic activities. The total dissolved solids values range from 0.75 to 5.6g/l.Isotopic characterization with stable isotopes (δ2H and δ18O) of Grombalia aquifer system identified geochemistry processes that control water chemistry. In addition, the multivariate statistical technique (Principal Component Analysis) was used to identify the origin, the recharge mode and geochemical processes controlling groundwater quality. The principal reactions responsible for the hydrochemical evolution in the Grombalia groundwater fall into three categories: (1) denitrification process; (2) dissolution of salts; and (3) irrigation return flow process. Tritium data in groundwater from the study area suggest the existence of pre1950 and post1960 recharge. © 2012 Elsevier Ltd and INQUA.

Geochemical processes in a calcareous sandstone aquifer during managed aquifer recharge with desalinated seawater

Science.gov (United States)

Ganot, Yonatan; Russak, Amos; Siebner, Hagar; Bernstein, Anat; Katz, Yoram; Guttman, Jospeh; Kurtzman, Daniel

2017-04-01

In the last three years we monitor Managed Aquifer Recharge (MAR) of post-treated desalinated seawater (PTDES) in an infiltration pond, at the Menashe site that overlies the northern part of the Israeli Coastal Aquifer. The PTDES are stabilized with CaCO3 during post-treatment in the desalination plant and their chemical composition differs from those of any other water recharged to the aquifer and of the natural groundwater. We use suction cups in the unsaturated zone, shallow observation wells within the pond and production wells that encircles the MAR Menashe site, to study the geochemical processes during MAR with PTDES. Ion-enrichment (remineralization) of the recharged water was observed in both unsaturated zone and shallow observation wells samples. Enrichment occurs mainly in the first few meters below the pond surface by ion-exchange processes. Mg2+ enrichment is most prominent due to its deficiency in the PTDES. It is explained by ion-exchange with Ca2+, as the PTDES (enriched with Ca2+) infiltrates through a calcareous-sandstone aquifer with various amount of adsorbed Mg2+ (3-27 meq/kg). Hence, the higher concentration of Ca+2 in the PTDES together with its higher affinity to the sediments promotes the release of Mg2+ ions to the recharged water. Water isotopes analysis of the production wells were used to estimate residence time and mixing with local groundwater. At the end of 2016, it was found that the percentage of PTDES in adjacent down-gradient production wells was around 10%, while more distant or up-gradient wells show no mixing with PTDES. The distinct isotope contrast between the recharged desalinated seawater (δ2H=+11.2±0.2‰) and the local groundwater (δ2H ranged from -22.7 to -16.7‰) is a promising tool to evaluate future mixing processes at the Menshae MAR site. Using the Menashe MAR system for remineralization could be beneficial as a primary or complementary post-treatment technique. However, the sustainability of this process is

Predicting Seawater Intrusion in Coastal Groundwater Boreholes Using Self-Potential Data

Science.gov (United States)

Graham, M.; MacAllister, D. J.; Jackson, M.; Vinogradov, J.; Butler, A. P.

2017-12-01

Many coastal groundwater abstraction wells are under threat from seawater intrusion: this is exacerbated in summer by low water tables and increased abstraction. Existing hydrochemistry or geophysical techniques often fail to predict the timing of intrusion events. We investigate whether the presence and transport of seawater can influence self-potentials (SPs) measured within groundwater boreholes, with the aim of using SP monitoring to provide early warning of saline intrusion. SP data collection: SP data were collected from a coastal groundwater borehole and an inland borehole (> 60 km from the coast) in the Seaford Chalk of southern England. The SP gradient in the inland borehole was approximately 0.05 mV/m, while that in the coastal borehole varied from 0.16-0.26 mV/m throughout the monitoring period. Spectral analysis showed that semi-diurnal fluctuations in the SP gradient were several orders of magnitude higher at the coast than inland, indicating a strong influence from oceanic tides. A characteristic decrease in the gradient, or precursor, was observed in the coastal borehole several days prior to seawater intrusion. Modelling results: Hydrodynamic transport and geoelectric modelling suggest that observed pressure changes (associated with the streaming potential) are insufficient to explain either the magnitude of the coastal SP gradient or the semi-diurnal SP fluctuations. By contrast, a model of the exclusion-diffusion potential closely matches these observations and produces a precursor similar to that observed in the field. Sensitivity analysis suggests that both a sharp saline front and spatial variations in the exclusion efficiency arising from aquifer heterogeneities are necessary to explain the SP gradient observed in the coastal borehole. The presence of the precursor in the model depends also on the presence and depth of fractures near the base of the borehole. Conclusions: Our results indicate that SP monitoring, combined with hydrodynamic

Review of LCA studies of solid waste management systems--part II: methodological guidance for a better practice.

Science.gov (United States)

Laurent, Alexis; Clavreul, Julie; Bernstad, Anna; Bakas, Ioannis; Niero, Monia; Gentil, Emmanuel; Christensen, Thomas H; Hauschild, Michael Z

2014-03-01

Life cycle assessment (LCA) is increasingly used in waste management to identify strategies that prevent or minimise negative impacts on ecosystems, human health or natural resources. However, the quality of the provided support to decision- and policy-makers is strongly dependent on a proper conduct of the LCA. How has LCA been applied until now? Are there any inconsistencies in the past practice? To answer these questions, we draw on a critical review of 222 published LCA studies of solid waste management systems. We analyse the past practice against the ISO standard requirements and the ILCD Handbook guidelines for each major step within the goal definition, scope definition, inventory analysis, impact assessment, and interpretation phases of the methodology. Results show that malpractices exist in several aspects of the LCA with large differences across studies. Examples are a frequent neglect of the goal definition, a frequent lack of transparency and precision in the definition of the scope of the study, e.g. an unclear delimitation of the system boundaries, a truncated impact coverage, difficulties in capturing influential local specificities such as representative waste compositions into the inventory, and a frequent lack of essential sensitivity and uncertainty analyses. Many of these aspects are important for the reliability of the results. For each of them, we therefore provide detailed recommendations to practitioners of waste management LCAs. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hydro-geochemical characterization of Treated Domestic Waste Water for possible use in homestead irrigation and managed aquifer recharge in the coastal city of Khulna, Bangladesh

Science.gov (United States)

Hamid, T.; Ahmed, K. M.

2016-12-01

Bangladesh is among the most densely populated countries in the world. Rapid and unplanned urbanization in Bangladesh has resulted in heterogeneous land use pattern and larger demands for municipal water. To meet the ever-increasing demand of water for such population, the usage of treated domestic waste water (DWW) has become a viable option that can serve specific purposes, i.e. homestead irrigation, managed aquifer recharge (MAR) in major cities like Khulna, the largest city in the southwest coastal region. It is an attractive solution to minimize the deficit between the demand and supply of water in the study area where, in specific parts, city-dwellers suffer year round shortage of potable water due to high salinity in shallow depths. However, certain degree of treatment is mandatory for DWW in order to ensure the compliance of the output water with a set of standards and regulations for the DWW reuse. At present, the DWW is being treated through Constructed Wetlands but the treated water is not used and discharged into the sewer system. Wastewater that has been treated through a constructed wetland is a resource that can be used for productive uses in homestead garden irrigation, artificial aquifer recharge, and other non-potable uses. The study addresses the effectiveness of constructed wetlands in improving the quality of wastewater through on the hydro-geochemical characterization of both raw and treated DWW as well as baseline water quality analysis of surface and ground water in and around the treatment plant with consideration of seasonal variations. The study aims at sustainable development through conservation of water, satisfaction of demands, reliability of water supply, contribution to urban food supply, sustenance of livelihood and replenishment of the depleting aquifer by assessing the suitability of the treated DWW for various non-potable uses and also to provide guidelines for possible uses of treated DWW without adverse impact on environment

Review of methodologies for Social LCA

DEFF Research Database (Denmark)

Jørgensen, Andreas; Hauschild, Michael Zwicky

on their approaches to the goal and scope definition, inventory, and impact assessment phases of LCA. The review concludes that a main methodical difference lies in the definition of impact categories to be included in the assessment as well as in the formulation of indicators. Another challenging aspect is the data...... collection. Some SLCA proposals opinion that the use of generic process data is not feasible in SLCA, because social impacts are claimed not to be process specific but rather company specific. This change could easily imply a strong need for site-specific data leading to a very demanding data collection...

Variability in benthic exchange rate, depth, and residence time beneath a shallow coastal estuary

Science.gov (United States)

Russoniello, C. J.; Michael, H. A.; Heiss, J.

2017-12-01

Hydrodynamically-driven exchange of water between the water column and shallow seabed aquifer, benthic exchange, is a significant and dynamic component of coastal and estuarine fluid budgets, but wave-induced benthic exchange has not been measured in the field. Mixing between surface water and groundwater solutes promotes ecologically important chemical reactions, so quantifying benthic exchange rates, depths, and residence times, constrains estimates of coastal chemical cycling. In this study, we present the first field-based direct measurements of wave-induced exchange and compare it to exchange induced by the other primary drivers of exchange - tides, and currents. We deployed instruments in a shallow estuary to measure benthic exchange and temporal variability over an 11-day period. Differential pressure sensors recorded pressure gradients across the seabed, and up-and down-looking ADCPs recorded currents and pressures from which wave parameters, surface-water currents, and water depth were determined. Wave-induced exchange was calculated directly from 1) differential pressure measurements, and indirectly with an analytical solution based on wave parameters from 2) ADCP and 3) weather station data. Groundwater flow models were used to assess the effects of aquifer properties on benthic exchange depth and residence time. Benthic exchange driven by tidal pumping or current-bedform interaction was calculated from tidal stage variation and from ADCP-measured currents at the bed, respectively. Waves were the primary benthic exchange driver (average = 20.0 cm/d, maximum = 92.3 cm/d) during the measurement period. Benthic exchange due to tides (average = 3.7 cm/d) and current-bedform interaction (average = 6.5x10-2 cm/d) was much lower. Wave-induced exchange calculated from pressure measurements and ADCP-measured wave parameters matched well, but wind-based rates underestimated wave energy and exchange. Groundwater models showed that residence time and depth increased

Seawater intrusion mapping using electrical resistivity tomography and hydrochemical data. An application in the coastal area of eastern Thermaikos Gulf, Greece.

Science.gov (United States)

Kazakis, N; Pavlou, A; Vargemezis, G; Voudouris, K S; Soulios, G; Pliakas, F; Tsokas, G

2016-02-01

The aim of this study was to determine the extent and geometrical characteristics of seawater intrusion in the coastal aquifer of the eastern Thermaikos Gulf, Greece. Hydrochemical data and geoelectrical measurements were combined and supplemented to determine the hydrochemical regime of the study site in regard to seawater phenomena. Chemical analysis of groundwater was performed in 126 boreholes and fifteen electrical resistivity tomographies (ERT) were measured, whereas in two sites the ERT measurements were repeated following the wet season. The Cl(-) concentrations recorded reached 2240 mg/L indicating seawater intrusion which was also verified by ionic ratios. The ionic ratios were overlapped and a seawater intrusion map (SWIM) was produced. A significant part of the coastal aquifer (up to 150 km(2)) is influenced by seawater intrusion. The areas with the most intensive salinization are located between Nea Kallikratia-Epanomi and Aggelochori-Peraia. According to the ERTs, in the influenced areas the salinization of the aquifer exceeds 1 km toward the mainland and its depth reaches 200 m. In the area surrounding Thessaloniki airport, the ERTs revealed salinization of the upper aquifer to depths of up to 40 m, whereas the lower aquifer is uninfluenced. This abnormal distribution of seawater intrusion demonstrates the value of geoelectrical methods in the study of seawater intrusion especially in areas with limited available hydrochemical data. Copyright © 2015 Elsevier B.V. All rights reserved.

A tomato ER-type Ca2+-ATPase, LCA1, has a low thapsigargin-sensitivity and can transport manganese

DEFF Research Database (Denmark)

Johnson, Neil A.; Liu, F; Weeks, P. D.

2008-01-01

and directly via in vitro ATP hydrolysis. We found LCA1 to be approximately 300-fold less sensitive to thapsigargin than animal SERCAs, whereas ECA1 was thapsigargin-resistant. LCA1 showed typical pharmacological sensitivities to cyclopiazonic acid, vanadate, and eosin, consistent with it being a P...

Recharge beneath low-impact design rain gardens and the influence of El Niño Southern Oscillation on urban, coastal groundwater resources

Science.gov (United States)

Newcomer, M. E.; Gurdak, J. J.

2011-12-01

Groundwater resources in urban, coastal environments are highly vulnerable to increased human pressures and climate variability. Impervious surfaces, such as buildings, roads, and parking lots prevent infiltration, reduce recharge to underlying aquifers, and increase contaminants in surface runoff that often overflow sewage systems. To mitigate these effects, cities worldwide are adopting low impact design (LID) approaches that direct runoff into natural vegetated systems, such as rain gardens that reduce, filter, and slow stormwater runoff, and are hypothesized to increase infiltration and recharge rates to aquifers. The effects of LID on recharge rates and quality is unknown, particularly during intense precipitation events for cities along the Pacific coast in response to interannual variability of the El Niño Southern Oscillation (ENSO). Using vadose zone monitoring sensors and instruments, I collected and monitored soil, hydraulic, and geochemical data to quantify the rates and quality of infiltration and recharge to the California Coastal aquifer system beneath a LID rain garden and traditional turf-lawn setting in San Francisco, CA. The data were used to calibrate a HYDRUS-3D model to simulate recharge rates under historical and future variability of ENSO. Understanding these processes has important implications for managing groundwater resources in urban, coastal environments.

Variability in Benthic Exchange Rate, Depth, and Residence Time Beneath a Shallow Coastal Estuary

Science.gov (United States)

Russoniello, Christopher J.; Heiss, James W.; Michael, Holly A.

2018-03-01

Hydrodynamically driven benthic exchange of water between the water column and shallow seabed aquifer is a significant and dynamic component of coastal and estuarine fluid budgets. Associated exchange of solutes promotes ecologically important chemical reactions, so quantifying benthic exchange rates, depths, and residence times constrains coastal chemical cycling estimates. We present the first combined field, numerical, and analytical modeling investigation of wave-induced exchange. Temporal variability of exchange was calculated with data collected by instruments deployed in a shallow estuary for 11 days. Differential pressure sensors recorded pressure gradients across the seabed, and up- and down-looking ADCPs recorded currents and pressures to determine wave parameters, surface-water currents, and water depth. Wave-induced exchange was calculated (1) directly from differential pressure measurements, and indirectly with an analytical model based on wave parameters from (2) ADCP and (3) wind data. Wave-induced exchange from pressure measurements and ADCP-measured wave parameters matched well, but both exceeded wind-based values. Exchange induced by tidal pumping and current-bed form interaction—the other primary drivers in shallow coastal waters were calculated from tidal stage variation and ADCP-measured currents. Exchange from waves (mean = 20.0 cm/d; range = 1.75-92.3 cm/d) greatly exceeded exchange due to tides (mean = 3.7 cm/d) and current-bed form interaction (mean = 6.5 × 10-2 cm/d). Groundwater flow models showed aquifer properties affect wave-driven benthic exchange: residence time and depth increased and exchange rates decreased with increasing hydraulic diffusivity (ratio of aquifer permeability to compressibility). This new understanding of benthic exchange will help managers assess its control over chemical fluxes to marine systems.

Neonatal disease environment limits the efficacy of retinal transplantation in the LCA8 mouse model

OpenAIRE

Cho, Seo-Hee; Song, Ji Yun; Shin, Jinyeon; Kim, Seonhee

2016-01-01

Background Mutations of Crb1 gene cause irreversible and incurable visual impairment in humans. This study aims to use an LCA8-like mouse model to identify host-mediated responses that might interfere with survival, retinal integration and differentiation of grafted cells during neonatal cell therapy. Methods Mixed retinal donor cells (1?~?2???104) isolated from neural retinas of neonatal eGFP transgenic mice were injected into the subretinal space of LCA8-like model neonatal mice. Markers of...

The magnitude and origin of groundwater discharge to eastern U.S. and Gulf of Mexico coastal waters

Science.gov (United States)

Befus, Kevin; Kroeger, Kevin D.; Smith, Christopher G.; Swarzenski, Peter W.

2017-01-01

Fresh groundwater discharge to coastal environments contributes to the physical and chemical conditions of coastal waters, but the role of coastal groundwater at regional to continental scales remains poorly defined due to diverse hydrologic conditions and the difficulty of tracking coastal groundwater flow paths through heterogeneous subsurface materials. We use three-dimensional groundwater flow models for the first time to calculate the magnitude and source areas of groundwater discharge from unconfined aquifers to coastal waterbodies along the entire eastern U.S. We find that 27.1 km3/yr (22.8–30.5 km3/yr) of groundwater directly enters eastern U.S. and Gulf of Mexico coastal waters. The contributing recharge areas comprised ~175,000 km2 of U.S. land area, extending several kilometers inland. This result provides new information on the land area that can supply natural and anthropogenic constituents to coastal waters via groundwater discharge, thereby defining the subterranean domain potentially affecting coastal chemical budgets and ecosystem processes.

Valg af afværge med inddragelse af livscyklusvurdering (LCA)

DEFF Research Database (Denmark)

Lemming, Gitte; Chambon, Julie Claire Claudia; Binning, Philip John

2012-01-01

Livscyklusvurdering (LCA) er anvendt til at sammenligne miljøeffekterne ved forskellige alternativer til at rense op på to forskellige TCE-forurenede grunde. De sammenlignede afværgealternativer for Lokalitet 1 er (i) in situ stimuleret reduktiv deklorering, (ii) in situ termisk desorption og (iii...

Assessment of chemical quality of groundwater in coastal volcano-sedimentary aquifer of Djibouti, Horn of Africa

Science.gov (United States)

Ahmed, Abdoulkader Houssein; Rayaleh, Waiss Elmi; Zghibi, Adel; Ouddane, Baghdad

2017-07-01

This research is conducted to evaluate the current status of hydrogeochemical contaminants and their sources in groundwater in the volcano-sedimentary aquifer of Djibouti. Groundwater samples were mostly collected from the volcanic and inferoflux aquifers and then were analyzed for quality on physicochemical parameters (EC, pH, Temperature, Cl-, SO42-, HCO3-, NO3-, Na+, Ca2+, Mg2+, K+, Br-, F-), minor and trace elements (Li, Ba, B, Sr, Si, Al, Cr, Fe, Mn, Mo, Pb, Co, Cu, Ni, Zn, Ti, V, As, Se). The interpretations of hydrochemical data are shown numerically and graphically through the Piper diagram such as the multivariate statistical analysis, binary diagram, the calculation of the saturation indexes, the index of base exchanges and ratio of Na+/Cl-, SO42-/Cl-, HCO3-/Cl-. The seawater ratio and ionic deviation in the groundwater were calculated using the chloride concentration. These processes can be used as indicators of seawater intrusion progress. This study reveals three groundwater quality groups and how the quality of water supply has been deteriorated through the process of seawater intrusion. The seawater intrusion extends into the Gulf basalts aquifer that covers nearly 12% of the whole area according to some observations. Some toxic elements present in drinking water (As and Se) have already exceeded the maximum permissible in almost the entire of the Gulf basalts aquifer affected by seawater intrusion. Indeed, some correlations were found between As, Se, with electrical conductivity and among other minor and trace elements such as Br, B, Sr, Co and Cr. It indicates that all these elements are mainly controlled by naturel/geogenic processes. The Principal component Analysis and the Hierarchical Cluster Analysis have led to the confirmation of the hypotheses developed in the previous hydrochemical study in which two factors explain the major hydrochemical processes in the aquifer. These factors reveal first the existence of an intensive intrusion of

Regional Variation of CH4 and N2 Production Processes in the Deep Aquifers of an Accretionary Prism.

Science.gov (United States)

Matsushita, Makoto; Ishikawa, Shugo; Nagai, Kazushige; Hirata, Yuichiro; Ozawa, Kunio; Mitsunobu, Satoshi; Kimura, Hiroyuki

2016-09-29

Accretionary prisms are mainly composed of ancient marine sediment scraped from the subducting oceanic plate at a convergent plate boundary. Large amounts of anaerobic groundwater and natural gas, mainly methane (CH4) and nitrogen gas (N2), are present in the deep aquifers associated with an accretionary prism; however, the origins of these gases are poorly understood. We herein revealed regional variations in CH4 and N2 production processes in deep aquifers in the accretionary prism in Southwest Japan, known as the Shimanto Belt. Stable carbon isotopic and microbiological analyses suggested that CH4 is produced through the non-biological thermal decomposition of organic matter in the deep aquifers in the coastal area near the convergent plate boundary, whereas a syntrophic consortium of hydrogen (H2)-producing fermentative bacteria and H2-utilizing methanogens contributes to the significant production of CH4 observed in deep aquifers in midland and mountainous areas associated with the accretionary prism. Our results also demonstrated that N2 production through the anaerobic oxidation of organic matter by denitrifying bacteria is particularly prevalent in deep aquifers in mountainous areas in which groundwater is affected by rainfall.

LCA as a Tool for Assessing Product and Process Oriented Eco-Innovations Undertaken by Enterprises

Directory of Open Access Journals (Sweden)

Rybaczewska-Błażejowska Magdalena

2017-09-01

Full Text Available This paper examines the application of life cycle assessment (LCA as an approach to foster the product and process oriented eco- innovation of enterprises, using the fruit and vegetable processing plant as an example. LCA, which is traditionally used to assess the impacts of a single product system on the environment, was applied in the enterprise context. This was made possible by forming an indicator describing the environmental profile of an enterprise, which is calculated by the sum of the multiplication of the environmental impact assessment (LCIA results for individual unit processes within a particular impact category and their weights reflecting the structure of production in an enterprise. In order to distinguish and indicate the direction in which an enterprise should undertake its eco-innovative actions (implementing eco-innovations within the product or production process the LCIA results are presented individually for products and production processes. The research was conducted in full compliance with the LCA methodology. LCA proved that the analysed enterprise has the largest negative impacts on the environment in the following impact categories: marine eco-toxicity, freshwater eco-toxicity, freshwater eutrophication, human toxicity and natural land transformation. They result primarily from the consumption of thermal and electric energy in the production processes. Therefore, to improve energy efficiency, the enterprise should take eco-innovative actions in the processes applied.

PestLCI - a model for estimating field emissions of pesticides in agricultural LCA

DEFF Research Database (Denmark)

Birkved, Morten; Hauschild, Michael Zwicky

2006-01-01

of a product or service is a specific element of LCA termed life cycle inventory (LCI). Estimation of chemical emissions in agricultural LCA is typically based on standard emission factors which at best are determined by a few physical-chemical substance properties and the use scenario of the chemical compound...... to the different environmental compartments. It estimates the fractions of the applied quantity which is emitted to the air, surface water, and groundwater compartment based on information which will normally be available to the model user about: type and time of application, crop species and development stage...... for other regions of the world. (c) 2006 Elsevier B.V. All rights reserved....

Coastal freshwater resources management in the frame of climate change: application to three basins (Italy, Morocco, Portugal)

Science.gov (United States)

Masson, E.; Antonellini, M.; Dentinho, T.; Khattabi, A.

2009-04-01

Climate change becomes an increasing constraint in IWRM and many effects are expected in coastal watersheds like sea level rise and its consequences (i.e. beach erosion, salt water intrusion, soil salinization, groundwater and surface water pollution…) or water budget changes (i.e. seasonal and inter-annual fluctuations) and an increase of extreme events (i.e. floods, rainfalls and droughts). Beside this physical changes one can also observed the increase of water demand in coastal areas due to population growth and development of tourism activities. Both effects (e.g. physical and socio-economical) must be included into any coastal freshwater management option for a mid-term / long-term approach to set water mass/basin management plans as expected in European countries by the WDF or elsewhere in an IWRM objective. The Waterknow project funded by EraNet-Circle-Med program aims to develop a tool to help decisions makers in the implementation of IWRM plans in coastal areas that will have to cope with climate change effects and socio-economical pressures. This interdisciplinary project is applied to three basins (e.g. Fiumi Uniti Bevano, Italy; Terceira Island, Portugal and Taheddart, Morocco) and seeks to integrate and to develop research achievements in coastal hydrogeology, economical and land use modeling in each basin. In the Fiumi Uniti Bevano basin, a detailed hydrogeological survey was performed during the summer 2008. Twenty auger holes with an average spacing of 350 m where drilled with the objective of determining the top groundwater quality in the coastal aquifer. At the same time, we collected the chemical and physical parameters of the surface waters. The data collected in the field show that a fresh groundwater lens is still present in the aquifer of the backshore area below the coastal dunes and that the surface water is all brackish to salty. In the northern part of the study area, the fresh groundwater lens in the backshore zone is missing, as

Geochemical Processes During Managed Aquifer Recharge With Desalinated Seawater

Science.gov (United States)

Ganot, Y.; Holtzman, R.; Weisbrod, N.; Russak, A.; Katz, Y.; Kurtzman, D.

2018-02-01

We study geochemical processes along the variably-saturated zone during managed aquifer recharge (MAR) with reverse-osmosis desalinated seawater (DSW). The DSW, post-treated at the desalination plant by calcite dissolution (remineralization) to meet the Israeli water quality standards, is recharged into the Israeli Coastal Aquifer through an infiltration pond. Water quality monitoring during two MAR events using suction cups and wells inside the pond indicates that cation exchange is the dominant subsurface reaction, driven by the high Ca2+ concentration in the post-treated DSW. Stable isotope analysis shows that the shallow groundwater composition is similar to the recharged DSW, except for enrichment of Mg2+, Na+, Ca2+, and HCO3-. A calibrated variably-saturated reactive transport model is used to predict the geochemical evolution during 50 years of MAR for two water quality scenarios: (i) post-treated DSW (current practice) and (ii) soft DSW (lacking the remineralization post-treatment process). The latter scenario was aimed to test soil-aquifer-treatment (SAT) as an alternative post-treatment technique. Both scenarios provide an enrichment of ˜2.5 mg L-1 in Mg2+ due to cation exchange, compared to practically zero Mg2+ currently found in the Israeli DSW. Simulations of the alternative SAT scenario provide Ca2+ and HCO3- remineralization due to calcite dissolution at levels that meet the Israeli standard for DSW. The simulated calcite content reduction in the sediments below the infiltration pond after 50 years of MAR was low (<1%). Our findings suggest that remineralization using SAT for DSW is a potentially sustainable practice at MAR sites overlying calcareous sandy aquifers.

Geochemical processes during managed aquifer recharge with desalinated seawater

Science.gov (United States)

Ganot, Y.; Holtzman, R.; Weisbrod, N.; Russak, A.; Katz, Y.; Kurtzman, D.

2017-12-01

In this work we study the geochemical processes along the variably-saturated zone during managed aquifer recharge (MAR) with reverse-osmosis desalinated seawater (DSW) to an infiltration pond at the Menashe site, located above the Israeli coastal aquifer. The DSW is post-treated by calcite dissolution (remineralization) in order to meet the Israeli desalinated water quality criteria. Suction cups and monitoring wells inside the pond were used to monitor water quality during two MAR events on 2015 and 2016. Results show that cation exchange is dominant, driven by the high Ca2+ concentration in the post-treated DSW. Stable isotope analysis shows that the composition of the shallow groundwater is similar to the recharged DSW, but with enrichment of Mg2+, Na+, Ca2+ and HCO3-. A calibrated variably-saturated reactive transport model was used to predict the geochemical evolution during 50 years of MAR with two water quality scenarios: post-treated DSW and soft DSW (without post-treatment). The latter scenario was aimed to test soil-aquifer-treatment as an alternative post-treatment technique. In terms of water quality, the results of the two scenarios were found within the range of the desalinated water criteria. Mg2+ enrichment was stable ( 2.5 mg L-1), higher than the zero concentration found in the Israeli DSW. Calcite content reduction was low (<1%) along the variably-saturated profile, after 50 years of MAR. This suggests that using soil-aquifer-treatment as a remineralization technique for DSW is potentially a sustainable practice, which is limited only by the current hydraulic capacity of the Menashe MAR site.

LCA to choose among alternative design solutions: The case study of a new Italian incineration line

International Nuclear Information System (INIS)

Scipioni, A.; Mazzi, A.; Niero, M.; Boatto, T.

2009-01-01

At international level LCA is being increasingly used to objectively evaluate the performances of different Municipal Solid Waste (MSW) management solutions. One of the more important waste management options concerns MSW incineration. LCA is usually applied to existing incineration plants. In this study LCA methodology was applied to a new Italian incineration line, to facilitate the prediction, during the design phase, of its potential environmental impacts in terms of damage to human health, ecosystem quality and consumption of resources. The aim of the study was to analyse three different design alternatives: an incineration system with dry flue gas cleaning (without- and with-energy recovery) and one with wet flue gas cleaning. The last two technological solutions both incorporating facilities for energy recovery were compared. From the results of the study, the system with energy recovery and dry flue gas cleaning revealed lower environmental impacts in relation to the ecosystem quality. As LCA results are greatly affected by uncertainties of different types, the second part of the work provides for an uncertainty analysis aimed at detecting the extent output data from life cycle analysis are influenced by uncertainty of input data, and employs both qualitative (pedigree matrix) and quantitative methods (Monte Carlo analysis).

Milestone 4.1 ∙ First draft on complemented LCA methodology

DEFF Research Database (Denmark)

Larsen, Henrik Fred; Olsen, Stig Irving; Hauschild, Michael Zwicky

As described in deliverable 4.1, D4.1 (Larsen et al. 2007) NEPTUNE is using two main types of life cycle impact assessment (LCIA) methodologies when doing LCA studies on the waste water treatment technologies included. The basic methodology is the well known existing EDIP97 methodology (Wenzel et...

Aquifer Characterization from Surface Geo-electrical Method, western coast of Maharashtra, India

Science.gov (United States)

DAS, A.; Maiti, D. S.

2017-12-01

Knowledge of aquifer parameters are necessary for managing groundwater amenity. These parameters are evaluated through pumping tests bring off from bore wells. But it is quite expensive as well as time consuming to carry out pumping tests at various sites and sometimes it is difficult to find bore hole at every required site. Therefore, an alternate method is put forward in which the aquifer parameters are evaluated from surface geophysical method. In this method, vertical electrical sounding (VES) with Schlumberger configuration were accomplished in 85 stations over Sindhudurg district. Sindhudurg district is located in the Konkan region of Maharashtra state, India. The district is located between north latitude 15°37' and 16° 40' and east longitude 73° 19' and 74° 13'. The area is having hard rock and acute groundwater problem. In this configuration, we have taken the maximum current electrode spacing of 200 m for every vertical electrical sounding (VES). Geo-electrical sounding data (true resistivity and thickness) is interpreted through resistivity inversion approach. The required parameters are achieved through resistivity inversion technique from which the aquifer variables (D-Z parameters, mean resistivity, hydraulic conductivity, transmissivity, and coefficient of anisotropy) are calculated by using some empirical formulae. Cross-correlation investigation has been done between these parameters, which eventually used to characterize the aquifer over the study area. At the end, the contour plot for these aquifer parameters has been raised which reveals the detailed distribution of aquifer parameters throughout the study area. From contour plot, high values of longitudinal conductance, hydraulic conductivity and transmissivity are demarcate over Kelus, Vengurle, Mochemar and Shiroda villages. This may be due to intrusion of saline water from Arabian sea. From contour trends, the aquifers are characterized from which the groundwater resources could be

The long-term impacts of anthropogenic and natural processes on groundwater deterioration in a multilayered aquifer.

Science.gov (United States)

Sheikhy Narany, Tahoora; Sefie, Anuar; Aris, Ahmad Zaharin

2018-07-15

In many regions around the world, there are issues associated with groundwater resources due to human and natural factors. However, the relation between these factors is difficult to determine due to the large number of parameters and complex processes required. In order to understand the relation between land use allocations, the intrinsic factors of the aquifer, climate change data and groundwater chemistry in the multilayered aquifer system in Malaysia's Northern Kelantan Basin, twenty-two years hydrogeochemical data set was used in this research. The groundwater salinisation in the intermediate aquifer, which mainly extends along the coastal line, was revealed through the hydrogeochemical investigation. Even so, there had been no significant trend detected on groundwater salinity from 1989 to 2011. In contrast to salinity, as seen from the nitrate contaminations there had been significantly increasing trends in the shallow aquifer, particularly in the central part of the study area. Additionally, a strong association between high nitrate values and the areas covered with palm oil cultivations and mixed agricultural have been detected by a multiple correspondence analysis (MCA), which implies that the increasing nitrate concentrations are associated with nitrate loading from the application of N-fertilisers. From the process of groundwater salinisation in the intermediate aquifer, could be seen that it has a strong correlation the aquifer lithology, specifically marine sediments which are influenced by the ancient seawater trapped within the sediments. Copyright © 2018 Elsevier B.V. All rights reserved.

Environmental assessment of amine-based carbon capture Scenario modelling with life cycle assessment (LCA)

Energy Technology Data Exchange (ETDEWEB)

Brekke, Andreas; Askham, Cecilia; Modahl, Ingunn Saur; Vold, Bjoern Ivar; Johnsen, Fredrik Moltu

2012-07-01

This report contains a first attempt at introducing the environmental impacts associated with amines and derivatives in a life cycle assessment (LCA) of gas power production with carbon capture and comparing these with other environmental impacts associated with the production system. The report aims to identify data gaps and methodological challenges connected both to modelling toxicity of amines and derivatives and weighting of environmental impacts. A scenario based modelling exercise was performed on a theoretical gas power plant with carbon capture, where emission levels of nitrosamines were varied between zero (gas power without CCS) to a worst case level (outside the probable range of actual carbon capture facilities). Because of extensive research and development in the areas of solvents and emissions from carbon capture facilities in the latter years, data used in the exercise may be outdated and results should therefore not be taken at face value.The results from the exercise showed: According to UseTox, emissions of nitrosamines are less important than emissions of formaldehyde with regard to toxicity related to operation of (i.e. both inputs to and outputs from) a carbon capture facility. If characterisation factors for emissions of metals are included, these outweigh all other toxic emissions in the study. None of the most recent weighting methods in LCA include characterisation factors for nitrosamines, and these are therefore not part of the environmental ranking.These results shows that the EDecIDe project has an important role to play in developing LCA methodology useful for assessing the environmental performance of amine based carbon capture in particular and CCS in general. The EDecIDe project will examine the toxicity models used in LCA in more detail, specifically UseTox. The applicability of the LCA compartment models and site specificity issues for a Norwegian/Arctic situation will be explored. This applies to the environmental compartments

Detection of coastal and submarine discharge on the Florida Gulf Coast with an airborne thermal-infrared mapping system

Science.gov (United States)

Raabe, Ellen; Stonehouse, David; Ebersol, Kristin; Holland, Kathryn; Robbins, Lisa

2011-01-01

Along the Gulf Coast of Florida north of Tampa Bay lies a region characterized by an open marsh coast, low topographic gradient, water-bearing limestone, and scattered springs. The Floridan aquifer system is at or near land surface in this region, discharging water at a consistent 70-72°F. The thermal contrast between ambient water and aquifer discharge during winter months can be distinguished using airborne thermal-infrared imagery. An airborne thermal-infrared mapping system was used to collect imagery along 126 miles of the Gulf Coast from Jefferson to Levy County, FL, in March 2009. The imagery depicts a large number of discharge locations and associated warm-water plumes in ponds, creeks, rivers, and nearshore waters. A thermal contrast of 6°F or more was set as a conservative threshold for identifying sites, statistically significant at the 99% confidence interval. Almost 900 such coastal and submarine-discharge locations were detected, averaging seven to nine per mile along this section of coast. This represents approximately one hundred times the number of previously known discharge sites in the same area. Several known coastal springs in Taylor and Levy Counties were positively identified with the imagery and were used to estimate regional discharge equivalent to one 1st-order spring, discharging 100 cubic feet per second or more, for every two miles of coastline. The number of identified discharge sites is a conservative estimate and may represent two-thirds of existing features due to low groundwater levels at time of overflight. The role of aquifer discharge in coastal and estuarine health is indisputable; however, mapping and quantifying discharge in a complex karst environment can be an elusive goal. The results of this effort illustrate the effectiveness of the instrument and underscore the influence of coastal springs along this stretch of the Florida coast.

LCA versus RA - an introduction

DEFF Research Database (Denmark)

Olsen, Stig Irving

2000-01-01

Risk Assessment (RA) of chemicals is an environmental management tool used to assess the risk of specific chemicals, which are harmful to man or the environment under certain circumstances of use or in certain environmental recipients. Life Cycle Assessment (LCA) or environmental assessment...... of Industrial Products) developed in Denmark (Wenzel et al., 1997), respectively. The interactions between the two tools can be viewed from two different angles: 1. As a general reflection of how the tools supplement each other in the total environmental effort. 2. As an assessment of coincidences...... on Principles and Methods for Hazard and Risk Assessment)focuses on an assessment of the toxicological and ecotoxicological risks, the focus of this article's comparison of assessment principles, data requirements etc. will be on the assessment of toxicity and ecotoxicity in EDIP's impact assessment methodology...

Effects of Aquifer Development and Changes in Irrigation Practices on Ground-Water Availability in the Santa Isabel Area, Puerto Rico

Science.gov (United States)

Kuniansky, Eve L.; Gómez-Gómez, Fernando; Torres-Gonzalez, Sigfredo

2003-01-01

The alluvial aquifer in the area of Santa Isabel is located within the South Coastal Plain aquifer of Puerto Rico. Variations in precipitation, changes in irrigation practices, and increasing public-supply water demand have been the primary factors controlling water-level fluctuations within the aquifer. Until the late 1970s, much of the land in the study area was irrigated using inefficient furrow flooding methods that required large volumes of both surface and ground water. A gradual shift in irrigation practices from furrow systems to more efficient micro-drip irrigation systems occurred between the late 1970s and the late 1980s. Irrigation return flow from the furrow-irrigation systems was a major component of recharge to the aquifer. By the early 1990s, furrow-type systems had been replaced by the micro-drip irrigation systems. Water levels declined about 20 feet in the aquifer from 1985 until present (February 2003). The main effect of the changes in agricultural practices is the reduction in recharge to the aquifer and total irrigation withdrawals. Increases in ground-water withdrawals for public supply offset the reduction in ground-water withdrawals for irrigation such that the total estimated pumping rate in 2003 was only 8 percent less than in 1987. Micro-drip irrigation resulted in the loss of irrigation return flow to the aquifer. These changes resulted in lowering the water table below sea level over most of the Santa Isabel area. By 2002, lowering of the water table reversed the natural discharge along the coast and resulted in the inland movement of seawater, which may result in increased salinity of the aquifer, as had occurred in other parts of the South Coastal Plain. Management alternatives for the South Coastal Plain aquifer in the vicinity of Santa Isabel include limiting groundwater withdrawals or implementing artificial recharge measures. Another alternative for the prevention of saltwater intrusion is to inject freshwater or treated sewage

Biogeochemical cycling of arsenic in coastal salinized aquifers: Evidence from sulfur isotope study

Energy Technology Data Exchange (ETDEWEB)

Kao, Yu-Hsuan [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 106, Taiwan, ROC (China); Wang, Sheng-Wei [Agricultural Engineering Research Center, Chungli 320, Taiwan, ROC (China); Liu, Chen-Wuing, E-mail: lcw@gwater.agec.ntu.edu.tw [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 106, Taiwan, ROC (China); Wang, Pei-Ling [Institute of Oceanography, National Taiwan University, Taipei 106, Taiwan, ROC (China); Wang, Chung-Ho [Institute of Earth Sciences, Academia Sinica, Taipei 115, Taiwan, ROC (China); Maji, Sanjoy Kumar [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei 106, Taiwan, ROC (China)

2011-10-15

Arsenic (As) contamination of groundwater, accompanied by critical salinization, occurs in the southwestern coastal area of Taiwan. Statistical analyses and geochemical calculations indicate that a possible source of aqueous arsenic is the reductive dissolution of As-bearing iron oxyhydroxides. There are few reports of the influence of sulfate-sulfide redox cycling on arsenic mobility in brackish groundwater. We evaluated the contribution of sulfate reduction and sulfide re-oxidation on As enrichment using {delta}{sup 34}S{sub [SO{sub 4]}} and {delta}{sup 18}O{sub [SO{sub 4]}} sulfur isotopic analyses of groundwater. Fifty-three groundwater samples were divided into groups of high-As content and salinized (Type A), low-As and non-salinized (Type B), and high-As and non-salinized (Type C) groundwaters, based on hydro-geochemical analysis. The relatively high enrichment of {sup 34}S{sub [SO{sub 4]}} and {sup 18}O{sub [SO{sub 4]}} present in Type A, caused by microbial-mediated reduction of sulfate, and high {sup 18}O enrichment factor ({epsilon}{sub [SO{sub 4-H{sub 2O]}}}), suggests that sulfur disproportionation is an important process during the reductive dissolution of As-containing iron oxyhydroxides. Limited co-precipitation of ion-sulfide increased the rate of As liberation under anaerobic conditions. In contrast to this, Type B and Type C groundwater samples showed high {delta}{sup 18}O{sub [SO{sub 4]}} and low {delta}{sup 34}S{sub [SO{sub 4]}} values under mildly reducing conditions. Base on {sup 18}O mass balance calculations, the oxide sources of sulfate are from infiltrated atmospheric O{sub 2}, caused by additional recharge of dissolved oxygen and sulfide re-oxidation. The anthropogenic influence of extensive pumping also promotes atmospheric oxygen entry into aquifers, altering redox conditions, and increasing the rate of As release into groundwater. - Highlights: {yields} Seawater intrusion and elevated As are the main issues of groundwater in Taiwan

Managed Aquifer Recharge: from Local Research and Experiences to Regional Aquifer Storage and Recovery

Science.gov (United States)

Hendriks, D.; Faneca, M.; Oude Essink, G.; van Baaren, E.; Stuurman, R.; Delsman, J. R.; van Kempen, C.; de Louw, P.

2016-12-01

Many areas in the world experience periodic water shortages due to meteorological drought, salt water intrusion or over-exploitation of the water resources. Recently, it was established that the depletion of aquifers in many areas of the world is in an advanced state (Gleeson et al, 2012). This poses enormous challenges as 2.5 billion people and many companies depend on groundwater now and in the future (UN, 2015; ESG, 2016). A solution to increase robustness of water systems and prevent water shortage is subsurface storage of water during wet periods using Managed Aquifer Research (MAR). In addition to mitigation of water shortage, MAR can also reduce the occurrence and degree of flooding. Here, we present an overview of Deltares MAR expertise and available tools for up-scaling MAR. Deltares has experience with both research and implementation of MAR in different parts of the world under various hydro(geo)logical, climatic and socio-economic conditions. Various MAR techniques were assessed/tested in coastal areas of the Netherlands, Spain, New York, New Orleans and in Bangladesh. In some of these areas specific groundwater shortage related issues occur, such as salt water intrusion or subsidence. In Singapore, monitoring campaigns and modeling were done to design MAR by infiltration of water in over-exploited aquifers. In Abu Dhabi, geophysical methods were used to detect the optimal conditions for MAR systems. To effectively increase the robustness of groundwater systems up-scaling of MAR is required. For this purpose, Deltares developed tools that provide insight in the potential demand, possibilities and effectiveness of MAR at larger scales. The Quick scan tool for Fresh Groundwater Buffering provides insight on regional to national scale and is based on GIS-information of water demand, water resources, and subsurface properties. This quick scan tool has been applied for Mozambique, Kenya, India and Bangladesh. The Fresh Water Optimizer assesses the

Assessing sustainability of a low-input single-farm vegetable box-scheme using emergy and LCA methodology

DEFF Research Database (Denmark)

Markussen, Mads Ville; Kulak, M.; Østergård, Hanne

2012-01-01

for minimizing resource use are fuels and electricity. Substitution of these would require the use of renewable energy. However, an increase in inputs from society may imply a lower net-yield to society from the farm and would thus be less desirable. The LCA data are currently being analysed and these results......Sustainable development implies necessarily making use of renewable resources to a larger extent. Thus a sustainability assessment has to identify hotspots for reducing use of non-renewable resources and potentials for substitution of these with renewable resources. LCA as well as emergy assessment......, the emergy method lacks some of the standardization and robustness of LCA. In this study we apply both methods to the same case study. The case considered is an organic stockless vegetable farm of 7 ha in UK which distributes its products in weekly boxes to 250 local consumers. The farm has systematically...

Regional characterization of freshwater Use in LCA: modeling direct impacts on human health.

Science.gov (United States)

Boulay, Anne-Marie; Bulle, Cécile; Bayart, Jean-Baptiste; Deschênes, Louise; Margni, Manuele

2011-10-15

Life cycle assessment (LCA) is a methodology that quantifies potential environmental impacts for comparative purposes in a decision-making context. While potential environmental impacts from pollutant emissions into water are characterized in LCA, impacts from water unavailability are not yet fully quantified. Water use can make the resource unavailable to other users by displacement or quality degradation. A reduction in water availability to human users can potentially affect human health. If financial resources are available, there can be adaptations that may, in turn, shift the environmental burdens to other life cycle stages and impact categories. This paper proposes a model to evaluate these potential impacts in an LCA context. It considers the water that is withdrawn and released, its quality and scarcity in order to evaluate the loss of functionality associated with water uses. Regionalized results are presented for impacts on human health for two modeling approaches regarding affected users, including or not domestic uses, and expressed in disability-adjusted life years (DALY). A consumption and quality based scarcity indicator is also proposed as a midpoint. An illustrative example is presented for the production of corrugated board with different effluents, demonstrating the importance of considering quality, process effluents and the difference between the modeling approaches.

Influence the condition land subsidence and groundwater impact of Jakarta coastal area

Science.gov (United States)

Rahman, S.; Sumotarto, U.; Pramudito, H.

2018-01-01

Jakarta has been experiencing land subsidence for ten years due toerecting weight building and intensive extraction of groundwater for society drink water through ground water wells. Many groundwater extraction for drinkingwater has caused intensive scouring of land rock and further triggering land subsidence developed widely in coastal area of Jakarta. Measurement of the land subsidence has been performed by various experts and institutes. Between 1974 to 2010 subsidence has happened between 3 to 4.1 meters especially in Jakarta coastal area. Two major causes of the subsidence are identified. The first major cause is a result of erecting weight building such as hotels, appartments, and various human activities buildings. The second major cause is extracting ground water from aquifers bellow Jakarta land due to water deep wells down to the aquifer and traditional shallow water well of shallow or subsurface uncovered ground water. Weighter building and higher debit of water flow from deep water wells has fastened and deepened the land subsidence. Continuous measurement of land subsidence by means of geodetic as well as geophysical earth behaviour measurements need to be performed to monitor the rate, location as well as mapping of the land subsidence.

Seawater intrusion mapping using electrical resistivity tomography and hydrochemical data. An application in the coastal area of eastern Thermaikos Gulf, Greece

Energy Technology Data Exchange (ETDEWEB)

Kazakis, N., E-mail: kazanera@yahoo.com [Aristotle University of Thessaloniki, Department of Geology, Lab. of Engineering Geology & Hydrogeology, 54124 Thessaloniki (Greece); Pavlou, A. [Aristotle University of Thessaloniki, Department of Geology, Lab. of Engineering Geology & Hydrogeology, 54124 Thessaloniki (Greece); Vargemezis, G. [Aristotle University of Thessaloniki, Department of Geology, Lab. of Applied Geophysics, 54124 Thessaloniki (Greece); Voudouris, K.S.; Soulios, G. [Aristotle University of Thessaloniki, Department of Geology, Lab. of Engineering Geology & Hydrogeology, 54124 Thessaloniki (Greece); Pliakas, F. [Democritus University of Thrace, Department of Civil Engineering, Xanthi 67100 (Greece); Tsokas, G. [Aristotle University of Thessaloniki, Department of Geology, Lab. of Applied Geophysics, 54124 Thessaloniki (Greece)

2016-02-01

The aim of this study was to determine the extent and geometrical characteristics of seawater intrusion in the coastal aquifer of the eastern Thermaikos Gulf, Greece. Hydrochemical data and geoelectrical measurements were combined and supplemented to determine the hydrochemical regime of the study site in regard to seawater phenomena. Chemical analysis of groundwater was performed in 126 boreholes and fifteen electrical resistivity tomographies (ERT) were measured, whereas in two sites the ERT measurements were repeated following the wet season. The Cl{sup −} concentrations recorded reached 2240 mg/L indicating seawater intrusion which was also verified by ionic ratios. The ionic ratios were overlapped and a seawater intrusion map (SWIM) was produced. A significant part of the coastal aquifer (up to 150 km{sup 2}) is influenced by seawater intrusion. The areas with the most intensive salinization are located between Nea Kallikratia–Epanomi and Aggelochori–Peraia. According to the ERTs, in the influenced areas the salinization of the aquifer exceeds 1 km toward the mainland and its depth reaches 200 m. In the area surrounding Thessaloniki airport, the ERTs revealed salinization of the upper aquifer to depths of up to 40 m, whereas the lower aquifer is uninfluenced. This abnormal distribution of seawater intrusion demonstrates the value of geoelectrical methods in the study of seawater intrusion especially in areas with limited available hydrochemical data. - Highlights: • ERTs determined the geometrical characteristics of the saline aquifer. • An abnormal distribution of seawater intrusion was recorded. • Four ionic ratios overlapped and a seawater intrusion map was produced. • Cl{sup −} concentrations increased significantly from 2005 to 2010 by up to 1800 mg/L.

Seawater intrusion mapping using electrical resistivity tomography and hydrochemical data. An application in the coastal area of eastern Thermaikos Gulf, Greece

International Nuclear Information System (INIS)

Kazakis, N.; Pavlou, A.; Vargemezis, G.; Voudouris, K.S.; Soulios, G.; Pliakas, F.; Tsokas, G.

2016-01-01

The aim of this study was to determine the extent and geometrical characteristics of seawater intrusion in the coastal aquifer of the eastern Thermaikos Gulf, Greece. Hydrochemical data and geoelectrical measurements were combined and supplemented to determine the hydrochemical regime of the study site in regard to seawater phenomena. Chemical analysis of groundwater was performed in 126 boreholes and fifteen electrical resistivity tomographies (ERT) were measured, whereas in two sites the ERT measurements were repeated following the wet season. The Cl"− concentrations recorded reached 2240 mg/L indicating seawater intrusion which was also verified by ionic ratios. The ionic ratios were overlapped and a seawater intrusion map (SWIM) was produced. A significant part of the coastal aquifer (up to 150 km"2) is influenced by seawater intrusion. The areas with the most intensive salinization are located between Nea Kallikratia–Epanomi and Aggelochori–Peraia. According to the ERTs, in the influenced areas the salinization of the aquifer exceeds 1 km toward the mainland and its depth reaches 200 m. In the area surrounding Thessaloniki airport, the ERTs revealed salinization of the upper aquifer to depths of up to 40 m, whereas the lower aquifer is uninfluenced. This abnormal distribution of seawater intrusion demonstrates the value of geoelectrical methods in the study of seawater intrusion especially in areas with limited available hydrochemical data. - Highlights: • ERTs determined the geometrical characteristics of the saline aquifer. • An abnormal distribution of seawater intrusion was recorded. • Four ionic ratios overlapped and a seawater intrusion map was produced. • Cl"− concentrations increased significantly from 2005 to 2010 by up to 1800 mg/L.

Characterising aquifer treatment for pathogens in managed aquifer recharge.

Science.gov (United States)

Page, D; Dillon, P; Toze, S; Sidhu, J P S

2010-01-01

In this study the value of subsurface treatment of urban stormwater during Aquifer Storage Transfer Recovery (ASTR) is characterised using quantitative microbial risk assessment (QMRA) methodology. The ASTR project utilizes a multi-barrier treatment train to treat urban stormwater but to date the role of the aquifer has not been quantified. In this study it was estimated that the aquifer barrier provided 1.4, 2.6, >6.0 log(10) removals for rotavirus, Cryptosporidium and Campylobacter respectively based on pathogen diffusion chamber results. The aquifer treatment barrier was found to vary in importance vis-à-vis the pre-treatment via a constructed wetland and potential post-treatment options of UV-disinfection and chlorination for the reference pathogens. The risk assessment demonstrated that the human health risk associated with potable reuse of stormwater can be mitigated (disability adjusted life years, DALYs aquifer is integrated with suitable post treatment options into a treatment train to attenuate pathogens and protect human health.

LCA of strippable coatings and of steam vacuum technology used for nuclear plants decontamination

International Nuclear Information System (INIS)

Guidi, Giambattista; Cumo, Fabrizio; Santoli, Livio de

2010-01-01

The application of strippable coatings is an innovative technology for decontamination of nuclear plants and for any decontamination project aiming at removing surface contamination. An adhesive plastic coating is applied on the contaminated surface. The strippable coating is allowed to cure for up to 24 h, after which it can be easily peeled. The coating traps the contaminants in the polymer matrix. Strippable coatings are non-toxic and do not contain volatile compounds or heavy metals. Since the coating constitutes a solid waste, disposal is easier than treating contaminated liquid wastes, produced by the baseline technology: steam vacuum cleaning, based upon superheated pressurized water in order to remove contaminants from floors and walls. A life cycle assessment (LCA) has been carried out with the purpose of comparing the strippable coating with the steam vacuum technology. The functional unit of the study is represented by a surface of 1 m 2 to be decontaminated. The results of LCA achieved using Sima Pro 5.0 registered software confirm the good environmental performances of strippable coatings. Taking into account both LCA and environmental costs for liquid wastes, the advantages of strippable coatings will be more and more evident. (orig.)

How Subsurface Water Technologies (SWT) can Provide Robust, Effective, and Cost-Efficient Solutions for Freshwater Management in Coastal Zones

NARCIS (Netherlands)

Zuurbier, K.G.; Raat, K.J.; Paalman, M.; Oosterhof, A.T.; Stuyfzand, P.J.

2016-01-01

Freshwater resources in coastal zones are limited while demands are high, resulting in problems like seasonal water shortage, overexploitation of freshwater aquifers, and seawater intrusion. Three subsurface water technologies (SWT) that can provide robust, effective, and cost-efficient solutions to

Alluvial Aquifer

Data.gov (United States)

Kansas Data Access and Support Center — This coverage shows the extents of the alluvial aquifers in Kansas. The alluvial aquifers consist of unconsolidated Quaternary alluvium and contiguous terrace...

Protecting coastal abstraction boreholes from seawater intrusion using self-potential data

Science.gov (United States)

Graham, Malcolm; Butler, Adrian; MacAllister, Donald John; Vinogradov, Jan; Ijioma, Amadi; Jackson, Matthew

2016-04-01

We investigate whether the presence and transport of seawater can influence self-potentials (SPs) measured within coastal groundwater boreholes, with a view to using SP monitoring as part of an early warning system for saline intrusion. SP data were collected over a period of 18 months from a coastal groundwater borehole in the fractured Chalk of England. Spectral analysis of the results shows semi-diurnal fluctuations that are several orders of magnitude higher than those observed from monitoring of the Chalk more than 60 km inland, indicating a strong influence from oceanic tides. Hydrodynamic and geoelectric modelling of the coastal aquifer suggests that observed pressure changes (giving rise to the streaming potential) are not sufficient to explain the magnitude of the observed SP fluctuations. Simulation of the exclusion-diffusion potential, produced by changes in concentration across the saline front, is required to match the SP data from the borehole, despite the front being located some distance away. In late summer of 2013 and 2014, seawater intrusion occurred in the coastal monitoring borehole. When referenced to the shallowest borehole electrode, there was a characteristic increase in SP within the array, several days before any measurable increase in salinity. The size of this precursor increased steadily with depth, typically reaching values close to 0.3 mV in the deepest electrode. Numerical modelling suggests that the exclusion-diffusion potential can explain the magnitude of the precursor, but that the polarity of the change in SP cannot be replicated assuming a homogeneous aquifer. Small-scale models of idealised Chalk blocks were used to simulate the effects of discrete fractures on the distribution of SP. Initial results suggest that comparatively large reductions in voltage can develop in the matrix ahead of the front, in conjunction with a reduced or absent precursor in the vicinity of a fracture. Geophysical logging indicates the presence of a

Considerations in the extraction of uranium from a fresh-water aquifer - Miocene Oakville Sandstone, south Texas

International Nuclear Information System (INIS)

Henry, C.D.; Galloway, W.E.; Smith, G.E.

1982-01-01

The Miocene Oakville Sandstone is a major aquifer and uranium host beneath the Texas Coastal Plain. Present and future uranium mining by either surface or in situ methods could affect the availability and quality of Oakville ground water unless the mining is designed properly. Possible effects of mining, potential natural mitigation of these effects, and approaches to minimizing the impact of mining on the aquifer system are discussed. Both solution and surface mining may affect the availability of ground water by altering recharge characteristics and permeability. Because the volume of the aquifer affected by mining is small compared with its total volume, availability of Oakville ground water will probably not be reduced significantly, except in wells immediately adjacent to a mine. Mining may affect the quality of ground water by introducing chemicals that are not indigenous to the aquifer or by inducing chemical reactions that do not occur naturally or that occur at much slower rates. Most mining companies no longer use concentrated, ammonium-based leaches because of known problems in restoring water to its original chemistry. Natural and induced release of trace elements such as molybdenum is known to occur, but the geochemical controls on mobility and potential mitigating reactions in the aquifer are poorly understood. Because the affected aquifer volume is small, any deterioration of water quality will probably be localized. Observations and recommendations are presented on: regional and local baseline studies, determination of aquifer sensitivity, methods and goals of monitoring during and after mining, and need for research on poorly understood aspects of mining impact. Such impacts include chemical reactions and processes that affect the long-term release of trace elements

Water Quality Considerations on the Rise as the Use of Managed Aquifer Recharge Systems Widens

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Niels Hartog

2017-10-01

Full Text Available Managed Aquifer Recharge (MAR is a promising method of increasing water availability in water stressed areas by subsurface infiltration and storage, to overcome periods of drought, and to stabilize or even reverse salinization of coastal aquifers. Moreover, MAR could be a key technique in making alternative water resources available, such as reuse of communal effluents for agriculture, industry and even indirect potable reuse. As exemplified by the papers in this Special Issue, consideration of water quality plays a major role in developing the full potential for MAR application, ranging from the improvement of water quality to operational issues (e.g., well clogging or sustainability concerns (e.g., infiltration of treated waste water. With the application of MAR expanding into a wider range of conditions, from deserts to urban and coastal areas, and purposes, from large scale strategic storage of desalinated water and the reuse of waste water, the importance of these considerations are on the rise. Addressing these appropriately will contribute to a greater understanding, operational reliability and acceptance of MAR applications, and lead to a range of engineered MAR systems that help increase their effectiveness to help secure the availability of water at the desired quality for the future.

Closed-form analytical solutions for assessing the consequences of sea-level rise on unconfined sloping island aquifers

Science.gov (United States)

Chesnaux, R.

2016-04-01

Closed-form analytical solutions for assessing the consequences of sea-level rise on fresh groundwater oceanic island lenses are provided for the cases of both strip and circular islands. Solutions are proposed for directly calculating the change in the thickness of the lens, the changes in volume and the changes in travel time of fresh groundwater within island aquifers. The solutions apply for homogenous aquifers recharged by surface infiltration and discharged by a down-gradient, fixed-head boundary. They also take into account the inland shift of the ocean due to land surface inundation, this shift being determined by the coastal slope of inland aquifers. The solutions are given for two simple island geometries: circular islands and strip islands. Base case examples are presented to illustrate, on one hand, the amplitude of the change of the fresh groundwater lens thickness and the volume depletion of the lens in oceanic island with sea-level rise, and on the other hand, the shortening of time required for groundwater to discharge into the ocean. These consequences can now be quantified and may help decision-makers to anticipate the effects of sea-level rise on fresh groundwater availability in oceanic island aquifers.

Hydrology of aquifer systems in the Memphis area, Tennessee

Science.gov (United States)

Criner, James H.; Sun, P-C. P.; Nyman, Dale J.

1964-01-01

The Memphis area as described in .this report comprises about 1,300 square miles of the Mississippi embayment part of the Gulf Coastal Plain. The area is underlain by as much as 3,000 feet of sediments ranging in age from Cretaceous through Quaternary. In 1960, 150 mgd (million gallons per day) of water was pumped from the principal aquifers. Municipal pumpage accounted for almost half of this amount, and industrial pumpage a little more than half. About 90 percent of the water used in the area is derived from the '500-foot' sand, and most of the remainder is from the ?400-foot' sand; both sands are of Eocene age. A small amount of water for domestic use is pumped from the terrace deposits of Pliocene and Pleistocene age. Both the '500-foot' and the '1,400-foot' sands are artesian aquifers except in the southeastern part of the area; there the water level in wells in the '500-foot' sand is now below the overlying confining clay. Water levels in both aquifers have declined almost continuously since pumping began, but the rate of decline has increased rapidly since 1940. Water-level decline in the '1,400-foot' sand has been less pronounced since 1956. The cones of depression in both aquifers have expanded and deepened as a result of the annual increases in pumping, and an increase in hydraulic gradients has induced a greater flow of water into the area. Approximately 135 mgd entered the Memphis area through the '500-foot' sand aquifer in 1960, and, of this amount, 60 mgd originated as inflow from the east and about 75 mgd was derived from leakage from the terrace deposits, from the north, south, and west and from other sources. Of the water entering the '1,400-foot' sand, about 5 mgd was inflow from the east, and about half that amount was from each of the north, south, and west directions. The average rate of movement of water outside the area of heavy withdrawals is about 70 feet per year in the '500-foot' sand and about 40 feet per year in the '1,400-foot' sand

Transportation life cycle assessment (LCA) synthesis : life cycle assessment learning module series.

Science.gov (United States)

2015-03-12

The Life Cycle Assessment Learning Module Series is a set of narrated, self-advancing slideshows on : various topics related to environmental life cycle assessment (LCA). This research project produced the first 27 of such modules, which : are freely...

Life cycle assessment (LCA) of electricity generation technologies: Overview, comparability and limitations

DEFF Research Database (Denmark)

Turconi, Roberto; Boldrin, Alessio; Astrup, Thomas Fruergaard

2013-01-01

, nuclear, biomass, hydroelectric, solar photovoltaic (PV) and wind was carried out to identify ranges of emission data for GHG, NOx and SO2 related to individual technologies. It was shown that GHG emissions could not be used as a single indicator to represent the environmental performance of a system...... identified as follows: the energy recovery efficiency and the flue gas cleaning system for fossil fuel technologies; the electricity mix used during both the manufacturing and the construction phases for nuclear and renewable technologies; and the type, quality and origin of feedstock, as well as the amount....... The most critical methodological aspects in relation to LCA studies were identified as follows: definition of the functional unit, the LCA method employed (e.g., IOA, PCA and hybrid), the emission allocation principle and/or system boundary expansion. The most important technological aspects were...

Effects of climate variability on saltwater intrusions in coastal aquifers in Southern Denmark

Science.gov (United States)

Meyer, Rena; Sonnenborg, Torben; Engesgaard, Peter; Høyer, Anne-Sophie; Jørgensen, Flemming; Hisnby, Klaus; Hansen, Birgitte; Jensen, Jørn Bo; Piotrowski, Jan A.

2016-04-01

As in many other regions of the world fresh water supply in Denmark is based on groundwater resources. Aquifers in the low-lying areas in the south-west of Jutland are particularly vulnerable to saltwater intrusions which are likely to intensify due to relative sea level rise. To understand the dynamics and development of this complex flow system, the initial hydrodynamic conditions imposed by the last Scandinavian Ice Sheet (SIS) must be taken into account. The whole region has undergone changes in climatic and hydraulic conditions within the last 15000 years that may show influence on the present flow conditions. It is likely that the groundwater-flow dynamics, driven by the postglacial hydraulic head drop and the relative sea level rise are not yet equilibrated. Enhanced by the potential future sea level rise due to climate change, contamination of fresh-water aquifers will continue. The 2800-km2 - large coast-to-coast study area located in the southern part of Jutland was partly overridden by the Weichselian ice sheet. Geophysical and geological mapping shows salt water intrusions up to 20 km inland from the present coast. Based on a geological voxel model spanning Miocene through Quaternary deposits a large-scale 3D numerical groundwater flow and salt water transport model has been developed. It includes density-driven flow and simulates the distribution of the current saltwater intrusions and their evolution during the last 15000 years. Particle tracking and direct age simulations are performed to identify recharge areas and constrain groundwater ages. The simulated ages are compared to ages derived from isotope analysis of groundwater samples both from Miocene and Quaternary aquifers. The origin of the groundwater is determined based on isotopic and chemical composition. Additionally, heavy noble gas analysis is carried out to estimate recharge temperatures and mechanisms at locations where groundwater recharge during the last glaciation is indicated. This

Numerical modelling assessment of climate-change impacts and mitigation measures on the Querença-Silves coastal aquifer (Algarve, Portugal)

Science.gov (United States)

Hugman, Rui; Stigter, Tibor; Costa, Luis; Monteiro, José Paulo

2017-11-01

Predicted changes in climate will lead to seawater intrusion in the Querença-Silves (QS) coastal aquifer (south Portugal) during the coming century if the current water-resource-management strategy is maintained. As for much of the Mediterranean, average rainfall is predicted to decrease along with increasing seasonal and inter-annual variability and there is a need to understand how these changes will affect the sustainable use of groundwater resources. A density-coupled flow and transport model of the QS was used to simulate an ensemble of climate, water-use and adaptation scenarios from 2010 to 2099 taking into account intra- and inter-annual variability in recharge and groundwater use. By considering several climate models, bias correction and recharge calculation methods, a degree of uncertainty was included. Changes in rainfall regimes will have an immediate effect on groundwater discharge; however, the effect on saltwater intrusion is attenuated by the freshwater-saltwater interfaces' comparatively slow rate of movement. Comparing the effects of adaptation measures demonstrates that the extent of intrusion in the QS is controlled by the long-term water budget, as the effectiveness of both demand and supply oriented measures is proportional to the change in water budget, and that to maintain the current position, average groundwater discharge should be in the order of 50 × 106 m3 yr-1.

Application of Geophysical Method for Determining Seawater Intrusion in Coastal Aquifer

International Nuclear Information System (INIS)

Mohd Muzamil Mohd Hashim; Kamarudin Samuding; Mohd Hafiz Zawawi; Daung, J.A.D.; Mohd Hafiz Zulkurnain; Kamaruzaman Mohamad

2016-01-01

A study of seawater intrusion has been proposed in the coastal area of Pahang. Electrical resistivity tomography (ERT) is a geophysical technique that used in this study. The survey was conducted at UMP, Tanjung Batu and Nenasi using Wenner-Schlumberger protocol. Electrical resistivity profile obtained from the survey indicates an area with low resistivity value (<5Ωm) associated with the resistivity value of seawater. (author)

Combining urbanization and hydrodynamics data to evaluate sea level rise impacts on coastal water resources

Science.gov (United States)

Young, C. R.; Martin, J. B.

2016-02-01

Assessments of the potential for salt water intrusion due to sea level rise require consideration of both coastal hydrodynamic and human activity thresholds. In siliciclastic systems, sea level rise may cause salt intrusion to coastal aquifers at annual or decadal scales, whereas in karst systems salt intrudes at the tidal scalse. In both cases, human activity impacts the freshwater portion of the system by altering the water demand on the aquifer. We combine physicochemical and human activity data to evaluate impact of sea level rise on salt intrusion to siliclastic (Indian River Lagoon, Fl, USA) and karst (Puerto Morelos, Yucatan, Mexico) systems under different sea level rise rate scenarios. Two hydrodynamic modeling scenarios are considered; flux controlled and head controlled. Under a flux controlled system hydraulic head gradients remain constant during sea level rise while under a head controlled system hydraulic graidents diminish, allowing saltwater intrusion. Our model contains three key terms; aquifer recharge, groundwater discharge and hydraulic conductivity. Groundwater discharge and hydraulic conductivity were calculated based on high frequency (karst system) and decadal (siliciclastic system) field measurements. Aquifer recharge is defined as precipitation less evapotranspiration and water demand was evaluated based on urban planning data that provided the regional water demand. Water demand includes agricultural area, toursim, traffic patterns, garbage collection and total population. Water demand was initially estimated using a partial leaset squares regression based on these variables. Our model indicates that water demand depends most on agricultural area, which has changed significantly over the last 30 years. In both systems, additional water demand creates a head controlled scenario, thus increaseing the protential fo salt intrusion with projected sea level rise.

Experiential Knowledge Complements an LCA-Based Decision Support Framework

Directory of Open Access Journals (Sweden)

Heng Yi Teah

2015-09-01

Full Text Available A shrimp farmer in Taiwan practices innovation through trial-and-error for better income and a better environment, but such farmer-based innovation sometimes fails because the biological mechanism is unclear. Systematic field experimentation and laboratory research are often too costly, and simulating ground conditions is often too challenging. To solve this dilemma, we propose a decision support framework that explicitly utilizes farmer experiential knowledge through a participatory approach to alternatively estimate prospective change in shrimp farming productivity, and to co-design options for improvement. Data obtained from the farmer enable us to quantitatively analyze the production cost and greenhouse gas (GHG emission with a life cycle assessment (LCA methodology. We used semi-quantitative graphical representations of indifference curves and mixing triangles to compare and show better options for the farmer. Our results empower the farmer to make decisions more systematically and reliably based on the frequency of heterotrophic bacteria application and the revision of feed input. We argue that experiential knowledge may be less accurate due to its dependence on varying levels of farmer experience, but this knowledge is a reasonable alternative for immediate decision-making. More importantly, our developed framework advances the scope of LCA application to support practically important yet scientifically uncertain cases.

Projecting the environmental profile of Singapore's landfill activities: Comparisons of present and future scenarios based on LCA.

Science.gov (United States)

Khoo, Hsien H; Tan, Lester L Z; Tan, Reginald B H

2012-05-01

This article aims to generate the environmental profile of Singapore's Semakau landfill by comparing three different operational options associated with the life cycle stages of landfilling activities, against a 'business as usual' scenario. Before life cycle assessment or LCA is used to quantify the potential impacts from landfilling activities, an attempt to incorporate localized and empirical information into the amounts of ash and MSW sent to the landfill was made. A linear regression representation of the relationship between the mass of waste disposed and the mass of incineration ash generated was modeled from waste statistics between years 2004 and 2009. Next, the mass of individual MSW components was projected from 2010 to 2030. The LCA results highlighted that in a 'business as usual' scenario the normalized total impacts of global warming, acidification and human toxicity increased by about 2% annually from 2011 to 2030. By replacing the 8000-tonne barge with a 10000-tonne coastal bulk carrier or freighter (in scenario 2) a grand total reduction of 48% of both global warming potential and acidification can be realized by year 2030. Scenario 3 explored the importance of having a Waste Water Treatment Plant in place to reduce human toxicity levels - however, the overall long-term benefits were not as significant as scenario 2. It is shown in scenario 4 that the option of increased recycling championed over all other three scenarios in the long run, resulting in a total 58% reduction in year 2030 for the total normalized results. A separate comparison of scenarios 1-4 is also carried out for energy utilization and land use in terms of volume of waste occupied. Along with the predicted reductions in environmental burdens, an additional bonus is found in the expanded lifespan of Semakau landfill from year 2032 (base case) to year 2039. Model limitations and suggestions for improvements were also discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Use of Facade Mockups in in LCA Based Architectural Design

DEFF Research Database (Denmark)

Naboni, Emanuele

2017-01-01

Life Cycle Assessment is increasingly becoming important in façade architectural design. The presented research aims to describe an LCA architectural design approach based on the use of a Façade Mockup. The approach is applied and tested for the design Telecom Sustainable Campus’ façade, in Rome...

Environmental assessment of solid waste landfilling technologies by means of LCA-modeling.

Science.gov (United States)

Manfredi, Simone; Christensen, Thomas H

2009-01-01

By using life cycle assessment (LCA) modeling, this paper compares the environmental performance of six landfilling technologies (open dump, conventional landfill with flares, conventional landfill with energy recovery, standard bioreactor landfill, flushing bioreactor landfill and semi-aerobic landfill) and assesses the influence of the active operations practiced on these performances. The environmental assessments have been performed by means of the LCA-based tool EASEWASTE, whereby the functional unit utilized for the LCA is "landfilling of 1ton of wet household waste in a 10m deep landfill for 100 years". The assessment criteria include standard categories (global warming, nutrient enrichment, ozone depletion, photo-chemical ozone formation and acidification), toxicity-related categories (human toxicity and ecotoxicity) and impact on spoiled groundwater resources. Results demonstrate that it is crucially important to ensure the highest collection efficiency of landfill gas and leachate since a poor capture compromises the overall environmental performance. Once gas and leachate are collected and treated, the potential impacts in the standard environmental categories and on spoiled groundwater resources significantly decrease, although at the same time specific emissions from gas treatment lead to increased impact potentials in the toxicity-related categories. Gas utilization for energy recovery leads to saved emissions and avoided impact potentials in several environmental categories. Measures should be taken to prevent leachate infiltration to groundwater and it is essential to collect and treat the generated leachate. The bioreactor technologies recirculate the collected leachate to enhance the waste degradation process. This allows the gas collection period to be reduced from 40 to 15 years, although it does not lead to noticeable environmental benefits when considering a 100 years LCA-perspective. In order to more comprehensively understand the influence

Global land–ocean linkage: direct inputs of nitrogen to coastal waters via submarine groundwater discharge

International Nuclear Information System (INIS)

Beusen, A H W; Slomp, C P; Bouwman, A F

2013-01-01

The role of submarine groundwater discharge (SGD), the leakage of groundwater from aquifers into coastal waters, in coastal eutrophication has been demonstrated mostly for the North American and European coastlines, but poorly quantified in other regions. Here, we present the first spatially explicit global estimates of N inputs via SGD to coastal waters and show that it has increased from about 1.0 to 1.4 Tg of nitrate (NO 3 -N) per year over the second half of the 20th century. Since this increase is not accompanied by an equivalent increase of groundwater phosphorus (P) and silicon (Si), SGD transport of nitrate is an important factor for the development of harmful algal blooms in coastal waters. Groundwater fluxes of N are linked to areas with high runoff and intensive anthropogenic activity on land, with Southeast Asia, parts of North and Central America, and Europe being hot spots. (letter)

Issues of Sustainability of Coastal Groundwater Resources: Benin, West Africa

Directory of Open Access Journals (Sweden)

Andrew D. Mullen

2010-08-01

Full Text Available The largest city in Benin, West Africa (Cotonou, is reliant upon groundwater for its public water supply. This groundwater is derived from the Godomey well field which is located approximately 5 Km north of the coast of the Atlantic Ocean and in close proximity to Lake Nokoue—a shallow lake containing water with elevated concentration of chloride and other elements. Historical data indicate increased chloride concentration in a number of wells nearest to the lake, with unknown contribution from groundwater encroachment from the coastal area. Hence, there is substantial interest in better characterizing this groundwater system for the purpose of determining appropriate management practices and degree of sustainability. Among the efforts attempted to date are a series of numerical models ranging from assessment of flow to a recent effort to include density-dependent transport from the lake. In addition, substantial field characterization has been pursued including assessment of shallow water chemistry along the region of the coastal lagoon and border of the lake, characterization of hydraulic response to pumpage in the aquifer system, estimation of the distribution of electrical resistivity with depth along the coastal lagoons, and installation of multi-level piezometers at seven locations in the lake. When integrated across methods, these numerical and field results indicate that the lake remains a primary concern in terms of a source of salinity in the aquifer. Further, the coastal region appears to be more complex than previously suggested and may represent a future source of salt-water encroachment as suggested by current presence of saline waters at relatively shallow depths along the coast. Finally, hydraulic testing suggests that both natural and pumping-based fluctuations in water levels are present in this system. Substantial additional characterization and modeling efforts may provide a significantly greater understanding of the

Comparison of aquifer characteristics derived from local and regional aquifer tests.

Science.gov (United States)

Randolph, R.B.; Krause, R.E.; Maslia, M.L.

1985-01-01

A comparison of the aquifer parameter values obtained through the analysis of a local and a regional aquifer test involving the same area in southeast Georgia is made in order to evaluate the validity of extrapolating local aquifer-test results for use in large-scale flow simulations. Time-drawdown and time-recovery data were analyzed by using both graphical and least-squares fitting of the data to the Theis curve. Additionally, directional transmissivity, transmissivity tensor, and angle of anisotropy were computed for both tests. -from Authors Georgia drawdown transmissivity regional aquifer tests

Seasonal Variation of Infiltration Rates in a Managed Aquifer Recharge System: A Belgian Example

Science.gov (United States)

Samanta, S.; Sheng, Z.; Munster, C. L.; Houtte, E. V.

2017-12-01

Managed Aquifer Recharge (MAR) is a powerful tool in addressing water resources management issues. The Torreele water reuse facility is using MAR to address the problem of water sustainability in a coastal aquifer of Belgium. The Torreele MAR facility uses infiltration ponds to maintain the groundwater level and to prevent saltwater intrusion into the aquifer. The source of recharge is treated wastewater from the Torreele wastewater treatment plant (TWWTP) located 1.2 km inland. The TWWTP uses a state-of-the-art filtration mechanism with a combination of ultrafiltration (UF) and Reverse Osmosis (RO) techniques to assure that recharge water is of very high quality. Data collected at the Torreele MAR facility indicates reduced infiltration rates during the winter season when pond water temperatures vary from 1 to 10ºC. The proposed hypothesis for these lower infiltration rates may be a reduction in hydraulic conductivity due to changes in water viscosity. This study involves the determination of relationship between water temperature, infiltration rates, and hydraulic conductivity at the Torreele MAR facility. The results of this study will lead to an effective administration of the facility and provide an extensive understanding of the system.

Principal aquifers can contribute radium to sources of drinking water under certain geochemical conditions

Science.gov (United States)

Szabo, Zoltan; Fischer, Jeffrey M.; Hancock, Tracy Connell

2012-01-01

What are the most important factors affecting dissolved radium concentrations in principal aquifers used for drinking water in the United States? Study results reveal where radium was detected and how rock type and chemical processes control radium occurrence. Knowledge of the geochemical conditions may help water-resource managers anticipate where radium may be elevated in groundwater and minimize exposure to radium, which contributes to cancer risk. Summary of Major Findings: * Concentrations of radium in principal aquifers used for drinking water throughout the United States generally were below 5 picocuries per liter (pCi/L), the U.S. Environmental Protection Agency (USEPA) maximum contaminant level (MCL) for combined radium - radium-226 (Ra-226) plus radium-228 (Ra-228) - in public water supplies. About 3 percent of sampled wells had combined radium concentrations greater than the MCL. * Elevated concentrations of combined radium were more common in groundwater in the eastern and central United States than in other regions of the Nation. About 98 percent of the wells that contained combined radium at concentrations greater than the MCL were east of the High Plains. * The highest concentrations of combined radium were in the Mid-Continent and Ozark Plateau Cambro-Ordovician aquifer system and the Northern Atlantic Coastal Plain aquifer system. More than 20 percent of sampled wells in these aquifers had combined radium concentrations that were greater than or equal to the MCL. * Concentrations of Ra-226 correlated with those of Ra-228. Radium-226 and Ra-228 occur most frequently together in unconsolidated sand aquifers, and their presence is strongly linked to groundwater chemistry. * Three common geochemical factors are associated with the highest radium concentrations in groundwater: (1) oxygen-poor water, (2) acidic conditions (low pH), and (3) high concentrations of dissolved solids.

Assessing Resource Intensity and Renewability of Cellulosic Ethanol Technologies using Eco-LCA

Science.gov (United States)

Recognizing the contributions of natural resources and the lack of their comprehensive accounting in life cycle assessment (LCA) of cellulosic ethanol, an in-depth analysis of the contribution of natural resources in the life cycle of cellulosic ethanol derived from five differen...

LCA of Food and Agriculture

DEFF Research Database (Denmark)

Dijkman, Teunis Johannes; Basset-Mens, Claudine; Antón, Assumpció

2018-01-01

, preparation and waste of the food. In the waste management stage, food waste can be handled using a number of technologies, such as landfilling, incineration , composting or digestion. A number of case studies are looked at here where the life cycles of typical food products (meat , cheese, bread, tomatoes......This chapter deals with the application of Life Cycle Assessment to evaluate the environmental sustainability of agriculture and food processing. The life cycle of a food product is split into six stages: production and transportation of inputs to the farm, cultivation, processing, distribution...... , consumption and waste management . A large number of LCA studies focus on the two first stages in cradle-to-farm gate studies, as they are the stages where most impacts typically occur, due to animal husbandry and manure handling, production and use of fertilisers and the consumption of fuel to operate farm...

Incorporating Health Impacts from Exposure to Chemicals in Food Packaging in LCA

DEFF Research Database (Denmark)

Ernstoff, Alexi; Trier, Xenia; Jolliet, Oliver

2014-01-01

Life cycle assessments (LCA) on the environmental and public health impacts of food and beverage packaging materials have found some advantages to plastic over glass. Entirely missing from these evaluations are the health impacts of possible chemical, e.g. endocrine dis-ruptor, exposure through...... migration of chemicals from the packaging into the food product. We build a framework based on a life cycle perspective to predict which chemicals may be in a package that are not intentionally added ingredients, and we apply this approach to the US EPA’s CPCAT database. In total we find 1,154 chemicals...... within the CPCAT database related to food-contact materials; out of these 107 are potential endocrine disruptors according to the TEDX list of endocrine disruptors. We also build a framework in an effort to begin harmonizing LCA to include health impacts of chemical exposure related to food packaging...

Minimization of the LCA impact of thermodynamic cycles using a combined simulation-optimization approach

International Nuclear Information System (INIS)

Brunet, Robert; Cortés, Daniel; Guillén-Gosálbez, Gonzalo; Jiménez, Laureano; Boer, Dieter

2012-01-01

This work presents a computational approach for the simultaneous minimization of the total cost and environmental impact of thermodynamic cycles. Our method combines process simulation, multi-objective optimization and life cycle assessment (LCA) within a unified framework that identifies in a systematic manner optimal design and operating conditions according to several economic and LCA impacts. Our approach takes advantages of the complementary strengths of process simulation (in which mass, energy balances and thermodynamic calculations are implemented in an easy manner) and rigorous deterministic optimization tools. We demonstrate the capabilities of this strategy by means of two case studies in which we address the design of a 10 MW Rankine cycle modeled in Aspen Hysys, and a 90 kW ammonia-water absorption cooling cycle implemented in Aspen Plus. Numerical results show that it is possible to achieve environmental and cost savings using our rigorous approach. - Highlights: ► Novel framework for the optimal design of thermdoynamic cycles. ► Combined use of simulation and optimization tools. ► Optimal design and operating conditions according to several economic and LCA impacts. ► Design of a 10MW Rankine cycle in Aspen Hysys, and a 90kW absorption cycle in Aspen Plus.

Minimization of the LCA impact of thermodynamic cycles using a combined simulation-optimization approach

Energy Technology Data Exchange (ETDEWEB)

Brunet, Robert; Cortes, Daniel [Departament d' Enginyeria Quimica, Escola Tecnica Superior d' Enginyeria Quimica, Universitat Rovira i Virgili, Campus Sescelades, Avinguda Paisos Catalans 26, 43007 Tarragona (Spain); Guillen-Gosalbez, Gonzalo [Departament d' Enginyeria Quimica, Escola Tecnica Superior d' Enginyeria Quimica, Universitat Rovira i Virgili, Campus Sescelades, Avinguda Paisos Catalans 26, 43007 Tarragona (Spain); Jimenez, Laureano [Departament d' Enginyeria Quimica, Escola Tecnica Superior d' Enginyeria Quimica, Universitat Rovira i Virgili, Campus Sescelades, Avinguda Paisos Catalans 26, 43007 Tarragona (Spain); Boer, Dieter [Departament d' Enginyeria Mecanica, Escola Tecnica Superior d' Enginyeria, Universitat Rovira i Virgili, Campus Sescelades, Avinguda Paisos Catalans 26, 43007, Tarragona (Spain)

2012-12-15

This work presents a computational approach for the simultaneous minimization of the total cost and environmental impact of thermodynamic cycles. Our method combines process simulation, multi-objective optimization and life cycle assessment (LCA) within a unified framework that identifies in a systematic manner optimal design and operating conditions according to several economic and LCA impacts. Our approach takes advantages of the complementary strengths of process simulation (in which mass, energy balances and thermodynamic calculations are implemented in an easy manner) and rigorous deterministic optimization tools. We demonstrate the capabilities of this strategy by means of two case studies in which we address the design of a 10 MW Rankine cycle modeled in Aspen Hysys, and a 90 kW ammonia-water absorption cooling cycle implemented in Aspen Plus. Numerical results show that it is possible to achieve environmental and cost savings using our rigorous approach. - Highlights: Black-Right-Pointing-Pointer Novel framework for the optimal design of thermdoynamic cycles. Black-Right-Pointing-Pointer Combined use of simulation and optimization tools. Black-Right-Pointing-Pointer Optimal design and operating conditions according to several economic and LCA impacts. Black-Right-Pointing-Pointer Design of a 10MW Rankine cycle in Aspen Hysys, and a 90kW absorption cycle in Aspen Plus.

Aquifer Storage Recovery (ASR) of chlorinated municipal drinking water in a confined aquifer

Science.gov (United States)

Izbicki, John A.; Petersen, Christen E.; Glotzbach, Kenneth J.; Metzger, Loren F.; Christensen, Allen H.; Smith, Gregory A.; O'Leary, David R.; Fram, Miranda S.; Joseph, Trevor; Shannon, Heather

2010-01-01

About 1.02 x 106 m3 of chlorinated municipal drinking water was injected into a confined aquifer, 94-137 m below Roseville, California, between December 2005 and April 2006. The water was stored in the aquifer for 438 days, and 2.64 x 106 m3 of water were extracted between July 2007 and February 2008. On the basis of Cl data, 35% of the injected water was recovered and 65% of the injected water and associated disinfection by-products (DBPs) remained in the aquifer at the end of extraction. About 46.3 kg of total trihalomethanes (TTHM) entered the aquifer with the injected water and 37.6 kg of TTHM were extracted. As much as 44 kg of TTHMs remained in the aquifer at the end of extraction because of incomplete recovery of injected water and formation of THMs within the aquifer by reactions with freechlorine in the injected water. Well-bore velocity log data collected from the Aquifer Storage Recovery (ASR) well show as much as 60% of the injected water entered the aquifer through a 9 m thick, high-permeability layer within the confined aquifer near the top of the screened interval. Model simulations of ground-water flow near the ASR well indicate that (1) aquifer heterogeneity allowed injected water to move rapidly through the aquifer to nearby monitoring wells, (2) aquifer heterogeneity caused injected water to move further than expected assuming uniform aquifer properties, and (3) physical clogging of high-permeability layers is the probable cause for the observed change in the distribution of borehole flow. Aquifer heterogeneity also enhanced mixing of native anoxic ground water with oxic injected water, promoting removal of THMs primarily through sorption. A 3 to 4-fold reduction in TTHM concentrations was observed in the furthest monitoring well 427 m downgradient from the ASR well, and similar magnitude reductions were observed in depth-dependent water samples collected from the upper part of the screened interval in the ASR well near the end of the extraction

Hydrology of the Claiborne aquifer and interconnection with the Upper Floridan aquifer in southwest Georgia

Science.gov (United States)

Gordon, Debbie W.; Gonthier, Gerard

2017-04-24

The U.S. Geological Survey conducted a study, in cooperation with the Georgia Environmental Protection Division, to define the hydrologic properties of the Claiborne aquifer and evaluate its connection with the Upper Floridan aquifer in southwest Georgia. The effort involved collecting and compiling hydrologic data from the aquifer in subarea 4 of southwestern Georgia. Data collected for this study include borehole geophysical logs in 7 wells, and two 72-hour aquifer tests to determine aquifer properties.The top of the Claiborne aquifer extends from an altitude of about 200 feet above the North American Vertical Datum of 1988 (NAVD 88) in Terrell County to 402 feet below NAVD 88 in Decatur County, Georgia. The base of the aquifer extends from an altitude of about 60 feet above NAVD 88 in eastern Sumter County to about 750 feet below NAVD 88 in Decatur County. Aquifer thickness ranges from about 70 feet in eastern Early County to 400 feet in Decatur County.The transmissivity of the Claiborne aquifer, determined from two 72-hour aquifer tests, was estimated to be 1,500 and 700 feet squared per day in Mitchell and Early Counties, respectively. The storage coefficient was estimated to be 0.0006 and 0.0004 for the same sites, respectively. Aquifer test data from Mitchell County indicate a small amount of leakage occurred during the test. Groundwater-flow models suggest that the source of the leakage was the underlying Clayton aquifer, which produced about 2.5 feet of drawdown in response to pumping in the Claiborne aquifer. The vertical hydraulic conductivity of the confining unit between the Claiborne and Clayton aquifers was simulated to be about 0.02 foot per day.Results from the 72-hour aquifer tests run for this study indicated no interconnection between the Claiborne and overlying Upper Floridan aquifers at the two test sites. Additional data are needed to monitor the effects that increased withdrawals from the Claiborne aquifer may have on future water resources.

Interpolation of extensive routine water pollution monitoring datasets: methodology and discussion of implications for aquifer management.

Science.gov (United States)

Yuval, Yuval; Rimon, Yaara; Graber, Ellen R; Furman, Alex

2014-08-01

A large fraction of the fresh water available for human use is stored in groundwater aquifers. Since human activities such as mining, agriculture, industry and urbanisation often result in incursion of various pollutants to groundwater, routine monitoring of water quality is an indispensable component of judicious aquifer management. Unfortunately, groundwater pollution monitoring is expensive and usually cannot cover an aquifer with the spatial resolution necessary for making adequate management decisions. Interpolation of monitoring data is thus an important tool for supplementing monitoring observations. However, interpolating routine groundwater pollution data poses a special problem due to the nature of the observations. The data from a producing aquifer usually includes many zero pollution concentration values from the clean parts of the aquifer but may span a wide range of values (up to a few orders of magnitude) in the polluted areas. This manuscript presents a methodology that can cope with such datasets and use them to produce maps that present the pollution plumes but also delineates the clean areas that are fit for production. A method for assessing the quality of mapping in a way which is suitable to the data's dynamic range of values is also presented. A local variant of inverse distance weighting is employed to interpolate the data. Inclusion zones around the interpolation points ensure that only relevant observations contribute to each interpolated concentration. Using inclusion zones improves the accuracy of the mapping but results in interpolation grid points which are not assigned a value. The inherent trade-off between the interpolation accuracy and coverage is demonstrated using both circular and elliptical inclusion zones. A leave-one-out cross testing is used to assess and compare the performance of the interpolations. The methodology is demonstrated using groundwater pollution monitoring data from the coastal aquifer along the Israeli

Managing saltwater intrusion in coastal arid regions and its societal implications for agriculture

Directory of Open Access Journals (Sweden)

J. Grundmann

2016-05-01

Full Text Available Coastal aquifers in arid and semiarid regions are particularly at risk due to intrusion of salty marine water. Since groundwater is predominantly used in irrigated agriculture, its excessive pumping – above the natural rate of replenishment – strengthen the intrusion process. Using this increasingly saline water for irrigation, leads to a destruction of valuable agricultural resources and the economic basis of farmers and their communities. The limitation of resources (water and soil in these regions requires a societal adaptation and change in behaviour as well as the development of appropriate management strategies for a transition towards stable and sustainable future hydrosystem states. Besides a description of the system dynamics and the spatial consequences of adaptation on the resources availability, the contribution combines results of an empirical survey with stakeholders and physically based modelling of the groundwater-agriculture hydrosystem interactions. This includes an analysis of stakeholders' (farmers and decision makers behaviour and opinions regarding several management interventions aiming on water demand and water resources management as well as the thinking of decision makers how farmers will behave. In this context, the technical counter measures to manage the saltwater intrusion by simulating different groundwater pumping strategies and scenarios are evaluated from the economic and social point of view and if the spatial variability of the aquifer's hydrogeology is taken into consideration. The study is exemplarily investigated for the south Batinah region in the Sultanate of Oman, which is affected by saltwater intrusion into a coastal aquifer system due to excessive groundwater withdrawal for irrigated agriculture.

An evaluation of aquifer intercommunication between the unconfined and Rattlesnake Ridge aquifers on the Hanford Site

International Nuclear Information System (INIS)

Jensen, E.J.

1987-10-01

During 1986, Pacific Northwest Laboratory conducted a study of a portion of the Rattlesnake Ridge aquifer (confined aquifer) that lies beneath the B Pond - Gable Mountain Pond area of the Hanford Site. The purpose was to determine the extent of intercommunication between the unconfined aquifer and the uppermost regionally extensive confined aquifer, referred to as the Rattlesnake Ridge aquifer. Hydraulic head data and chemical data were collected from the ground water in the study area during December 1986. The hydraulic head data were used to determine the effects caused by water discharged to the ground from B Pond on both the water table of the unconfined aquifer and the potentiometric surface of the confined aquifer. The chemical data were collected to determine the extent of chemical constituents migrating from the unconfined aquifer to the confined aquifer. Analysis of chemical constituents in the Rattlesnake Ridge aquifer demonstrated that communication between the unconfined and confined aquifers had occurred. However, the levels of contaminants found in the Rattlesnake Ridge aquifer during this study were below the DOE Derived Concentration Guides

Comparison of environmental impact and energy efficiency of desalination processes by LCA

NARCIS (Netherlands)

Tarnacki, K.M.; Melin, T.; Jansen, A.E.; Medevoort, J. van

2011-01-01

In this study two desalination technologies have been compared by means of LCA with the focus on energy supply with a variety of scenarios based on different assumptions. The studied technologies are reverse osmosis and the newly developed technology Memstill where electrical energy demand is

Diagnosis of the Ghiss Nekor aquifer in order to elaborate the aquifer contract