A combination of a parallel fracture model with the PHREEQC-2 geochemical model wasdeveloped to simulate sequential flow and chemical transport with reactions in fracturedmedia where both laminar and turbulent flows occur. The integration of non-laminar flowresistances in one model produced relevant effects on water flow velocities, thus improvingmodel prediction capabilities on contaminant transport. The proposed conceptual modelconsists of 3D rock-blocks, separated by horizontal bedding plane fractures with variableapertures. Particle tracking solved the transport equations for conservative compounds andprovided input for PHREEQC-2. For each cluster of contaminant pathways, PHREEQC-2determined the concentration for mass-transfer, sorption/desorption, ion exchange, mineraldissolution/precipitation and biodegradation, under kinetically controlled reactive processes ofequilibrated chemical species. Field tests have been performed for the code verification. As anexample, the combined model has been applied to a contaminated fractured aquifer ofsouthern Italy in order to simulate the phenol transport. The code correctly fitted the fieldavailable data and also predicted a possible rapid depletion of phenols as a result of anincreased biodegradation rate induced by a simulated artificial injection of nitrates, upgradientto the sources.

A new method to study 3D saline front advancement in coastal fractured aquifers has beenpresented. Field groundwater salinity was measured in boreholes of the Bari (Southern Italy) coastalaquifer with depth below water table. Then, the Ghyben-Herzberg freshwater/saltwater (50%) sharpinterface and saline front position were determined by model simulations of the freshwater flowin 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 modelledfreshwater/saltwater saline front was used to convert each position (x, y) in groundwater to thewater salinity concentration at depth of 1.0 m. Moreover, a second best-fit procedure was appliedto 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 orderto assess effects of pumping on the saltwater-freshwater transition zone in the coastal aquifer, theNavier-Stokes (N-S) equations were applied to study transient density-driven flow and salt masstransport into freshwater of a single fracture. The rate of seawater/freshwater interface advancementgiven 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 during the transitionperiod of 112.8 days was easily highlighted on 3D salinity maps of Bari aquifer.

Artificial recharge is used to increase the availability of groundwaterstorage and reduce saltwater intrusion in coastal aquifers, where pumpingand droughts have severely impaired groundwater quality. Theimplementation of optimal recharge methods requires knowledge ofphysical, chemical, and biological phenomena involving water andwastewater filtration in the subsoil, together with engineering aspectsrelated to plant design and maintenance operations. This study uses anovel Decision Support System (DSS), which includes soil aquifertreatment (SAT) evaluation, to design an artificial recharge plant. The DSShelps users make strategic decisions on selecting the most appropriaterecharge methods and water treatment technologies at specific sites. Thiswill enable the recovery of safe water using managed aquifer recharge(MAR) practices, and result in reduced recharge costs. The DSS was builtusing an artificial intelligence technique and knowledge-based technology,related to both quantitative and qualitative aspects of water supply forartificial recharge. The DSS software was implemented using rules basedon the cumulative experience of wastewater treatment plant engineersand groundwater modeling. Appropriate model flow simulations wereperformed in porous and fractured coastal aquifers to evaluate thesuitability of this technique for enhancing the integrated water resourcesmanagement approach. Results obtained from the AQUASTRESSintegrated project and DRINKADRIA IPA CBC suggest the most effectivestrategies for wastewater treatments prior to recharge at specific sites.

Aquifer over-exploitation may increase coastal seawater intrusion by reducing freshwater availability. Fractured subsurface formations commonly host important freshwater reservoirs along sea coasts. These water resources are particularly vulnerable to the contamination due to seawater infiltration occurring through rapid pathways via fractures. Modeling of density driven fluid flow in fractured aquifers is complex, as their hydrodynamics are controlled by interactions between preferential flow pathways, 3D interconnected fractures and rock-matrix porosity distribution. Moreover, physical heterogeneities produce highly localized water infiltrations that make the modeling of saltwater transport in such aquifers very challenging. The new approach described in this work provides a reliable hydrogeological model suitable to reproduce local advancements of the freshwater/saltwater wedge in coastal aquifers. The proposed model use flow simulation results to estimate water salinities in groundwater at a specific depth (1 m) below water table by means of positions of the Ghyben-Herzberg saltwater/freshwater sharp interface along the coast. Measurements of salinity in 25 boreholes (i.e., salinity profiles) have been used for the model calibration. The results provide the groundwater salinity map in freshwater/saltwater transition coastal zones of the Bari (Southern Italy) fractured aquifer. Non-invasive geophysical measurements in groundwater, particularly into vertical 2D vertical cross-sections, were carried out by using the electrical resistivity tomography (ERT) in order to validate the model results. The presented integrated approach is very easy to apply and gives very realistic salinity maps in heterogeneous aquifers, without simulating density driven water flow in fractures.

Sono state utilizzate le equazioni Navier-Stokes (NS) per la risoluzione di un problema pratico ricorrente in acquiferi carsici costieri, vale a dire lo studio dello spostamento dell'interfaccia acqua salata/acqua dolce nelle fessure, conseguente a un sovra utilizzo della risorsa idrica sotterranea. La soluzione numerica di N-S determinata per l'acquifero costiero di Villanova di Ostuni (Brindisi) suggerisce una progressione nel tempo dell'interfaccia acqua salata/acqua dolce interpolabile con una funzione esponenziale. Le equazioni di N-S sono state risolte con un metodo convenzionale alle differenze finite, mostratosi più efficiente, per l'applicazione di questo articolo, del più sofisticato smoothed particle hydrodynamics (meshless method). Si è verificato che N-S è in grado di definire i valori transitori del flusso idrico nelle fessure, nonché il relativo profilo dei carichi piezometrici e delle velocità lungo la stessa fessura, ad ogni instante della simulazione.

An assessment of sea intrusion into coastal aquifers as a consequence of local sea-level rise (LSLR) due to climate change was carried out at Murgia and Salento in southern Italy. The interpolation of sea-level measurements at three tide-gauge stations was performed during the period of 2000 to 2014. The best In of measurements shows an increasing rale of LSLR ranging from 4.4 mm/y to 8.8 mm/y, which will result in a maximum LSLR of approximately 2 m during the 22nd century. The local rale of sea-level rise matches recent. 21st and 22nd century projections of mean global sea-level rise determined by other researchers, which include increased melting rates of the Greenland and Antarctic ice sheets, the effect of ocean thermal expansion, the melting of glaciers and ice caps, and changes in the quantity of stored land water. Subsequently, Ghyben-Herzberg's equation for the freshwater; saltwater interface was rewritten in order to determine the decrease in groundwater discharge due to the maximum LSLR. Groundwater flow simulations and ArcGIS elaborations of digital elevation models of the coast provided input data for the Ghyben-Herzberg calculation under the assumption of head-controlled systems. The progression of seawater intrusion due to LSLR suggests an impressive depletion of available groundwater discharge during the 22nd century, perhaps as much as 16.1% of current groundwater pumping for potable water in Salento. (C) 2016 Elsevier B.V. All rights reserved.

The best fit of tide-gauge measurements of two monitoring stations, located along Puglia coast (Southern Italy), provided local sea level rise (LSLR) rate of 8.8 mm/y during 2000-2014 years. This local rate matches 21st and 22nd century projections of the rate of mean global sea level rise, which includes ocean thermal expansion, glaciers, polar caps, Greenland and Antarctica's ice sheets melting, and by including changes in soil water storage. Under the assumption that this sea rise rate will remain constant, an increasing of seawater intrusion will be produced into the Puglia and others Mediterranean coastal aquifers. Model simulations have been applied to the Ostuni (Puglia) groundwater in order to quantify seawater encroachment in fractured coastal aquifers due to LSLR. The model implemented the Ghyben-Herzberg's equation of freshwater/saltwater sharp interface in order to determine the amount of the decrease in groundwater discharge due to the maximum LSLR during 22nd century. Since model results have foreseen an impressive depletion (over 16%) of groundwater discharge, MAR actions have been tested to prevent the seawater intrusion. The study has confirmed the suitability of MAR for enhancing the integrated water resources availability by reducing future groundwater depletions. MAR recovered 80 L/s of groundwater as a new source of water supply during summer at the Ostuni area. Therefore, MAR can be a useful measure to mitigate the impact of climate change on coastal aquifers as a direct measure, due to reducing salt water intrusion, and as an indirect one, due to increasing water resource.

Polychaete marine community distribution (specimens and species) along the coast of the Villanova (Brindisi, Italy) has been investigated. Two sites were sampled: the Port of Villanova and the sea at the outflow of a stream-channel, 1.5 km distant from the Port. The benthonic substratum was sampled for Polychaeta and other biota during March, May and July 2010. The collected Polychaeta were counted and classified. At the Villanova Port were recovered 21 species and 127 specimens of Syllidae and Orbiniidae, with a maximum of 66 specimens in July. At the second site we found only 15 specimens of Sabellidae during May 2010. Water quality and polychaete population have been treated by statistical methods to find the relationship between anthropogenic activities, climatic variables and polychaete population distribution. Finally, actions necessary to re-address the marine ecosystem at Villanova to the uncontaminated status, have been focalized by means of STELLA model.

Preferential flow pathways in a fractured aquifer may yield abrupt reductions of the water velocity in a well. We propose a new device for measuring low (5-13cmd(-1)) velocities in wells originating from fractures at different depths. The presented flowmeter has been applied in a well in the Bari (southern Italy) fractured aquifer. In the same well, the horizontal flowmeter velocity (9.6cmd(-1)) at 0.5m depth was compared with velocity (8cmd(-1)) derived from a field tracer test, providing a value 16.5% higher. Moreover, the flowmeter measurements at 1.5m depth gave a horizontal velocity of 7.2cmd(-1), which is 11% less than water flow velocity estimated from the field test. The new flowmeter implements the tracer point-dilution method in a plastic (PVC) pipe by causing the water flow to pass through an artificial filter. Laboratory calibration tests have confirmed the good performance of the proposed flowmeter technique, even for water flow up to 300cmd(-1). The flowmeter was sensitive to 0.1cmd(-1), with a detection limit of 1.5cmd(-1), i.e. half the measurable flow velocity of existing flowmeters in wells.Editor D. Koutsoyiannis; Associate editor S. Grimaldi ResumeLes circulations preferentielles dans un aquifere fracture peuvent produire des reductions brusques de la vitesse de l'eau dans un forage. Nous proposons un nouveau dispositif de mesure pour des vitesses faibles (5-13 cm j(-1)) dans les puits du fait de fractures a differentes profondeurs. Le debitmetre presente a ete utilise dans un puits de l'aquifere fissure de Bari (Sud de l'Italie). Dans le meme puits, la vitesse horizontale du debitmetre (9,6 cm j(-1)) a 0,5 m de profondeur a ete comparee a la vitesse (8 cm j(-1)) issue d'un test de tracage et fournissant une valeur plus forte de 16,5%. En outre, les mesures du debitmetre a 1,5 m de profondeur ont donne une vitesse horizontale de 7,2 cm j(-1), soit 11 % de moins que la vitesse de l'eau estimee a partir de l'essai sur le terrain. Le nouveau debitmetre utilise la methode de dilution d'un traceur ponctuel dans un tuyau de PVC en faisant passer l'eau a travers un filtre artificiel. Des tests de calage en laboratoire ont confirme la bonne performance de la technique du debitmetre propose, meme pour un ecoulement de l'eau allant jusqu'a 300 cm j(-1). La sensibilite du debitmetre est de 0,1 cm j(-1), et la limite de detection de 1,5 cm/j, soit la moitie de la vitesse d'ecoulement mesurable par les debitmetres en forage actuels.

Wedemonstrated that floods can induce severemicrobiological contamination of drinkingwater fromwells andsuggest strategies to better address water safety plans for groundwater drinking supplies. Since 2002, the ItalianWater Research Institute (IRSA) has detected hepatitis A virus, adenovirus, rotavirus, norovirus, and enterovirusin water samples fromwells in the Salento peninsula, southern Italy. Perturbations in the ionic strength inwaterflow can initiate strong virus detachments from terra rossa sediments in karst fractures. This study therefore exploredthe potential health impacts of prolonged runoff injections in Salento groundwater caused by severeflooding during October 2018. A mathematicalmodel for virus fate and transport in fractures was applied to determinethe impact of floodwater injection on groundwater quality by incorporating mechanisms that affectvirus attachment/detachment and survival in flowing water at microscale. This model predicted target concentrationsof enteric viruses that can occur unexpectedly inwells at considerable distances (5-8 km) from the runoffinjection site (sinkhole). Subsequently, the health impact of viruses in drinking water supplied fromcontaminated wells was estimated during the summer on the Salento coast. Specific unpublished doseresponsemodel coefficients were proposed to determine the infection probabilities for Echo-11 and Polio 1 enterovirusesthrough ingestion. Themedian (50%) risk of infectionwas estimated at 6.3 · 10-3with an uncertaintyof 23%. The predicted burden of diseases was 4.89 disability adjusted life years per year, i.e., twice the maximum tolerable disease burden. The results highlight the requirement for additional water disinfection treatments inSalento prior to the distribution of drinking water. Moreover, monthly controls of enteric virus occurrence inwater fromwells should be imposed by a newwater framework directive in semiarid regions because of the vulnerabilityof karst carbonate aquifers to prolonged floodwater injections and enteric virus contamination.

A new formula for determining increasing sea intrusion in coastal fractured rock aquifers as a consequence of local sea level rise (LSLR) was presented. The formula was applied to the Salento peninsula (Southern Italy), which is an important source of drinking water for locals and, it can be applied to any coastal groundwater at a regional scale in order to evaluate the impact of climate change on local water resources. Moreover the interpolation of tide- gauge measurements was performed at three monitoring stations from 2000 to 2014. The best fit of measurements provides a rate of LSLR ranging from 4.4 to 8.8 mm/y. This local calculated rate matches the recent 21st and 22nd century projections of mean global sea level rise. It includes the melting of Greenland and Antarctica's ice sheets, the effect of seawater thermal expansion, glaciers and ice caps melting and changes in land water storage quantity. Thus, the Ghyben-Herzberg's equation of freshwater/saltwater interface position was rewritten in order to determine the decrease in groundwater discharge due to the maximum LSLR during the 21st and 22nd centuries. Results regarding the progress of seawater intrusion due to LSLR suggest an impressive depletion of available groundwater volume, which locally may achieve 15% of current pumping for drinking purposes from Salento's groundwater. This reduction does not take into account groundwater impairment due to overexploitations. This study strongly suggests the need for a prompt actuation of measures in order to limit groundwater depletion in the near future.

L'innalzamento progressivo del livello del mare causatodai cambiamenti climatici sta compromettendo ildeflusso naturale degli acquiferi costieri, peggiorando laqualità e quantità dell'acqua di falda contenuta in essa.In questo studio, ci proponiamo di valutare l'impattodell'innalzamento locale del livello del mare (Local SeaLevel Rise - LSLR) sulla riduzione del deflusso naturaledi falda verso il mare, in particolare nell'area delle Murgee nella penisola salentina. A tal fine, sono stati interpolatii dati mareografici raccolti negli anni dal 2000 al2014, da tre stazioni (Bari, Otranto e Taranto) dislocatelungo il tratto studiato della costa pugliese. L'interpolazionedei dati di innalzamento del mare misurato segueun trend positivo con un tasso di crescita prossimo 8,8mm/anno. Il tasso si dimezza a 4,4 mm/anno nel casodi Otranto. Questo ha permesso di prevedere l'innalzamentomassimo di 2 m del LSL, in un lungo periodoprossimo a 200 anni. Questa previsione d'incrementodel LSL combacia con la previsione dell'innalzamentomedio globale del livello del mare (GSL) nel 2200,stimato da altri ricercatori, in seguito ai cambiamenticlimatici. In particolare tali previsioni considerano la fusionedei ghiacci della Groenlandia e dell'Antartide, l'effettodi espansione termica degli oceani indotto dall'innalzamentotermico per l'effetto serra, lo scioglimentodi ghiacciai e delle calotte di ghiaccio polari, includendoanche le variazioni dei volumi di acqua immagazzinatanel suolo.Nel presente lavoro è stata riscritta l'equazione diGhyben-Herzberg, rappresentativa dell'interfaccia acquadi falda / acqua di mare, per valutare la riduzione deldeflusso di falda conseguente all'innalzamento del livellodel mare. I parametri utili per il calcolo con Ghyben-Herzberg sono forniti da simulazioni computerizzate delflusso di falda, assumendo condizioni al contorno a "caricocontrollato" (o Head Controlled System). Il modellodigitale di elevazione della costa ricavato con tecnologiaLiDAR (www.sit.puglia.it), è stato elaborato in ArcGISper determinare l'arretramento locale del mare corrispondentea un massimo LSLR di 2 m. I risultati stimanouna cospicua riduzione del deflusso naturale di falda che,fino al 2200, raggiunge il 16% della portata attualmenteprelevata dalla falda carsica della penisola Salentina perapprovvigionamenti potabili.

The monitoring of hydrological processes within the vadose zone is usually difficult, especially in the presence of compact rock subsoil. The possibility of recognizing the trend of the structural lineaments in fractured systems has important fallout in the understanding water infiltration processes, especially when the groundwater flow is strongly affected by the presence of faults and fractures that constitute the preferred ways of water fluxes.This study aims to detect fracture lineaments on fractured rock formations from CASI hyperspectral airborne VNIR images, with a size of 60 cm of the spatial resolution, and collected during November 2014. Lineaments detected with such high resolution have been compared with the fracture lineaments detected by a Landsat 8 image acquired at the same time of the CASI acquisition.The method has processed several remote sensed images at different spatial resolution, and it has produced the visualization of numerous lineament maps, as result of the vertical and sub-vertical fractures of the investigated area. The study has been applied to the fractured limestone outcrop of the Murgia region (Southern Italy). Here the rock formation hosts a deep groundwater, which supplies freshwater for drinking and irrigations purposes. The number of the fractures allowed a rough estimation of the vertical average hydraulic conductivity of the rock outcrop. This value was compared with field saturated rock hydraulic conductivity measurements derived from large ring infiltrometer tests carried out on the same rock outcrop.

This study investigates the feasibility of management of aquifer recharge (MAR) in Lebanon by designingwell barriers to remove seawater intrusion from the fractured carbonate aquifers. Groundwater flow andsaltwater/freshwater 50% sharp interface have been modeled along the coastal area using the GhybeneHerzberg theory. The groundwater flow simulations have been supported by field transmissivity estimationsand depth measurements carried out on 44 wells during 2003. Results have shown theseawater intrusion in coastal aquifers at Jieh and Damour regions. Three well-injection barriers havebeen proposed. The water volumes for recharge and the barrier positions have been defined by means ofgroundwater flow simulations. MAR can provide a valuable contribution to colloid (even pathogen)removal from injectant water, although during water infiltration in subsoil the reduction of aquiferpermeability causes clogging. A simple new model for estimating the soil-rock permeability reductiondue to the well clogging has been presented. The MAR, including the soil aquifer treatment at Damourand Jieh regions, has been studied by considering aquifer transmissivity (and soil porosity) reductioncaused by clogging. Furthermore, the appropriate mixing of the injectant water by using reclaimed water,groundwater and surface water can be simulated using the proposed models. The time required toachieve 5% of rock permeability reduction at the proposed well barriers ranged from 71 to 935 d, bychanging water quality and flow rate for recharge. This study can assist regional governments with watermanagement in areas affected by scarcity of freshwater by implementing appropriate well-barrierprojects.

The theory for modeling non-equilibrium solute transport in porous media is still based on approximations to amodel proposed by Lapidus and Amundson in 1952 that has not been updated. This Mobile-Immobile Model(MIM) is based on the definition of a mass-transfer coefficient (?), which has been proven subject to some severelimitations. Measurements at both laboratory and field scales have demonstrated the scale-dependency of ?values. This means that the MIM theory fails in real applications, since ? is not constant, as defined in the kineticmodel theory, but is a time-residence (or distance) dependent coefficient. Multi-rate mass-transfer models havebeen proposed in recent literature to capture real-world solute transport with a multiple mass transfer. In thisstudy, we propose a novel model, which implements the analytical solution of Fick's second law of diffusiondirectly in the nonequilibrium advection/dispersion equation of solute transport in porous media. New modelsolutions properly fitted data collected during tracer tests carried out at the CNR-IRSA Laboratory (Bari, Italy) ina horizontal sandbox, 2m of length, by using sodium chloride as the conservative tracer. Selected breakthroughcurves at specific positions were used to validate the proposed model solution and estimate both conventionaland proposed coefficients of mass transfer. Results have shown a decreasing trend of ? from 0.09 to 0.04 h-1after about 1.2m of filtration for the investigated sand, whereas new solutions provide two scale-invariant tracercoefficients of rate of tracer mass-transfer (0.004 ± 0.005 h-1) and of tracer time delay (1.19 ± 0.01). Theproposed model performs very well, since it provides a readily solved analytical solution with respect to theconventional MIM. Results of the proposed MIM are very similar to those provided by the conventional MIM. Thenew model solution can be implemented in particle tracking or random walk software in order to solve twodimensionalnonequilibrium solute transport in groundwater.

Up to now, field studies set up to measure field-saturated hydraulic conductivity to evaluate contamination risks, have employed small cylinders that may not be representative of the scale of measurements in heterogeneous media. In this study, a large adjustable ring infiltrometer was designed to be installed on-site directly on rock to measure its field-saturated hydraulic conductivity. The proposed device is inexpensive and simple to implement, yet also very versatile, due to its large adjustable diameter that can be fixed on-site. It thus allows an improved representation of the natural system's heterogeneity, while also taking into consideration irregularities in the soil/rock surface. The new apparatus was tested on an outcrop of karstic fractured limestone overlying the deep Murge aquifer in the South of Italy, which has recently been affected by untreated sludge disposal, derived from municipal and industrial wastewater treatment plants. The quasi-steady vertical flow into the unsaturated fractures was investigated by measuring water levels during infiltrometer tests. Simultaneously, subsurface electrical resistivity measurements were used to visualize the infiltration of water in the subsoil, due to unsaturated water flow in the fractures. The proposed experimental apparatus works well on rock outcrops, and allows the repetition of infiltration tests at many locations in order to reduce model uncertainties in heterogeneous media.

This study investigated the modeling of variably saturated flow and Ni transport in frac- tured rocks at a site (Altamura, southern Italy) polluted in 2001 by unauthorized sludge waste disposal. Time-lapse electrical resistivity tomography (ERT) and infiltrometer experi- mental results were used to constrain near-surface boundary conditions in an unsaturated flow model. A plastic ring was used as an infiltrometer because its experimental setup is very versatile and adaptable to many different geological conditions, taking into con- sideration irregularities in the soil and rock surfaces. The proposed methodology allows switching from the tomography to the map of water pressure contour lines obtained by the model by making the time-lapse ERT an effective tool to reduce computational uncertain- ties. Simulation results predicted both the concentration and the residence time of the Ni in the vadose zone of the Altamura site. These results were used to successively investigate the horizontal Ni transport into the deep fractured aquifer. Simulations provided apparent Ni pathways in the groundwater and expected concentrations in a downstream well, placed 10.9 km from the contamination sources. The agreement of the results with the sampling data collected has confirmed that the groundwater was polluted for 16 mo by Ni. The con- tamination plume started during the winter of 2004 and moved in the groundwater toward the sea at an average velocity of 10 m/d.

Per valutare il grado di diffusione nell'ambiente di batteri antibiotico resistenti, sono stati esaminati campioni di acqua superficiale e sotterranea provenienti da una zona costiera della Puglia. Ceppi di Salmonella spp. e di E. coli sono stati isolati dalle acque superficiali di un canale che convoglia amare gli effluenti di un impianto di trattamento di reflui urbani e acque piovane. Nella stessa area sono state campionate acque sotterranee prelevate da 3 pozzi artesiani posti a diversa distanza dal mare, e che costeggiano il canale stesso. 82 ceppi batterici isolati da 24 campioni d'acqua sono stati sottoposti a test di antibiotico resistenza con due metodi: manuale, di diffusione da disco e automatizzato, VITEK ® 2 (bioMérieux, Marcy L'Etoile,France). I risultati ottenuti con le due metodiche non appaiono significativamente discordanti. I campioni di acqua superficiale sono risultati più contaminati rispetto a quelli di acqua sotterranea e con un numero più elevato di ceppi resistenti. Complessivamente lo studio mostra una notevole diffusione di batteri farmaco resistenti nell'ambiente e ciò potrebbe determinare implicazioni sulla salute dell'uomo rendendo più difficili le terapie antibiotiche.

Managed Aquifer Recharge (MAR) is becoming an attractive option for water storage in water reuse processes as it provides an additional treatment barrier to improve recharged water quality and buffers seasonal variations of water supply and demand. To achieve a better understanding about the level of pathogenic microorganisms and their relation with microbial indicators in these systems, five waterborne pathogens and four microbial indicators were monitored over one year in three European MAR sites operated with reclaimed wastewater. Giardia and Cryptosporidium (oo)cysts were found in 63.2 and 36.7% of the samples respectively. Salmonella spp. and helminth eggs were more rarely detected (16.3% and 12.5% of the samples respectively) and Campylobacter cells were only found in 2% of samples. At the Belgian site advanced tertiary treatment technology prior to soil aquifer treatment (SAT) produced effluent of drinking water quality, with no presence of the analysed pathogens. At the Spanish and Italian sites amelioration of microbiological water quality was observed between the MAR injectant and the recovered water. In particular Giardia levels decreased from 0.24-6.14 cysts/L to 0-0.01 cysts/L and from 0.4-6.2 cysts/L to 0-0.07 cysts/L in the Spanish and Italian sites respectively. Salmonella gene copies and Giardia cysts were however found in the water for final use and/or the recovered groundwater water at the two sites. Significant positive Spearman correlations (p<0.05, r(s) range: 0.45-0.95) were obtained, in all the three sites, between Giardia cysts and the most resistant microbial markers, Clostridium spores and bacteriophages.

Managed Aquifer Recharge (MAR) is increasingly being used for water recycling via aquifers and recovery for irrigation. Quantitative Microbial Risk Assessment (QMRA) was used to assess the human health risks from irrigation using reclaimed water and to evaluate the reduction in risk where MAR is used for irrigation management. Four MAR sites (Shafdan, Israel: Nardo, Italy: Bolivar, Australia; and Sabadell. Spain) that use reclaimed water for crop and/or park irrigation were evaluated, and the risk to human health was quantified in terms of DALYs (Disability Adjusted Life Years). The results indicated that median risks for all scenarios and pathogens evaluated were acceptable (<10(-6) DALYs) with the exception of risks from accidental aerosol ingestion and bacterial pathogens at the Nardo site. MAR was found to be one of the most important treatment barriers in terms of log(10) inactivation credits and hence a useful tool for recycled water irrigation management. The Shafdan site relied almost completely on the MAR treatment to reduce the human health risks from irrigation to acceptable levels. For the Nun site MAR was also an important barrier, where if MAR had not been used as part of the irrigation system the risk would be unacceptable for protozoa and viruses. The Bolivar and Sabadell sites had much larger and more technologically complex recycled water treatment systems and as such MAR was not a critical barrier in managing human health risks. (C) 2011 Elsevier B.V. All rights reserved.

We examine the use of numeric flow solutions of the Navier-Stokes (N-S) equations toimprove flow modeling in fractured karst aquifers. The N-S equations were discretized withboth the meshed finite difference method (FDM) and the meshless smoothed particlehydrodynamics method. The results using the FDM model were successfully compared withthose taken from the literature. The N-S equations were solved numerically for twopractical problems in karst aquifers: (a) the horizontal displacement of the saltwater/freshwater sharp interface in fissures due to groundwater overexploitation and (b) thepressure and velocity profiles in fissures in the vicinity of an injection well. In the firstproblem, the numeric N-S solution suggests an exponential time advancement of thefreshwater/saltwater interface in fissures. In the second problem, the unsteady watervelocity and pressure profiles were determined in fissures having variable apertures in thevicinity of an injection well. The N-S simulation results agreed well with the data collectedduring the test, thereby removing any uncertainty in the estimation of the aquifertransmissivity.

Two pilot-scale fractured aquifer models (FAMs) consisting of horizontal limestone slabs were employed to investigate the removal of biocolloids suspended in reclaimed wastewater. To better understand the behavior of real fractured aquifers, theseFAMsintentionallywerenot "clean".Thefracture apertures were randomly spread with soil deposits, and both FAMs were preflooded with reclaimed wastewater to simulate the field conditions of the Nardo` fractured aquifer in the Salento area, Italy, where fractures are not clean due to artificial groundwaterrecharge. One of the FAMs was injected with secondary effluent from a wastewater treatment plant collected prior to the chlorination step and the other with exactly the same effluent, which was further treated in a commercial membrane reactor. Consequently, the organic and pathogen concentrations were considerably higher in the secondary effluent than in the membrane reactor effluent. Injected wastewater wascontinuously recirculated. Pathogen removal was greater for the secondary wastewater than the cleaner membrane reactor effluent. A simple mathematical model was developed to describe fracture clogging. The results suggest that the hydraulic conductivity of FAMs can be significantly degraded due toretention of viable and inactivated biocolloids suspended in reclaimed wastewater.

Effluents derived from a municipal wastewater treatment plant were used for virus filtration/retention experiments by using a horizontal laboratory filter. Filtration tests were performed to examine how soil geochemical heterogeneity and fracture patterns affected the transport of viruses in groundwater in order to model the influence of reductive perturbations in ionic strength (IS) during wastewater filtration. Although perturbations of IS and velocity are known to result in resuspension of colloids, we found that the effect of soil geochemical heterogeneity can produce strong and instantaneous virus releases in fractured aquifers, likely an internal additional source of viruses. Sixteen limestone slabs were packed in a PVC box filter at the Bari Laboratory (South Italy) to replicate wastewater filtration throughout a fractured medium similar to the Bari carbonate aquifer. Terra rossa, which is an aggregate of sand, silt and clay, was unevenly spread on the surface of each limestone slab within the filter. Since the mineralogical composition of terra rossa includes iron (hematite, magnetite, and goethite) oxides, the soil exhibited localized unfavorable colloid/collector interactions for attachment. In contrast, soil-free parts of the fracture surfaces maintained favorable colloid/collector interactions. We found in our experiments that the lowering of IS due to the reduction of water salt content, which could occur during runoff injections after rainfall, might be sufficient to cause strong detachment of viruses from fracture surfaces, allowing further migration into the groundwater. The model in this work can predict the count and pathways of released viruses in groundwater fractures under soil geochemical heterogeneity and originated by reductions of IS, by using analytical solutions.

Model predictions of flow and pollutant transport in fractured rocks are subject to uncertainties due to imprecise knowledge of the position, orientation, length, aperture and density of the fractures. These properties are difficult to quantify precisely because fractures are located in depth in subsoil and, generally, tectonic and stratigraphic studies may provide only fracture frequency and their orientation. Subsequently, the use of the "equivalent" continuum models might help hydrogeologists to solve flow and pollutant transport problems in fractured aquifers, when fracture properties are unknown. The study presented herein has quantified the limitations of the equivalent continuum model when it is applied to simulate groundwater flow and pollutant transports in limestone aquifers. Both discrete and continuum model outputs have been compared with results derived from a pumping tracer test, carried out at Bari fractured aquifer. The test results have shown a delay of velocity estimated using continuum models, with respect to the discrete model, that decreases by increasing the hydraulic conductivity of the limestone aquifer under consideration. Maximum discrepancies have been noted for conductivity (< 10-4 m/s) typically associated with non-karst limestone aquifers. The tortuosity has been then included into the codes in order to address fl ow velocity calculations in numerical codes, such as MT3DMS. Successful simulations of flow and pollutant transport have been carried out at the Bari fractured aquifers by using tortuosity. A «tortuosity/conductivity» relationship has been also proposed in order to estimate tortuosity in fractured limestone aquifers, when results of tracer tests are not available.