GS4 - Resource Evaluation and Environmental ...

GS4 - Resource Evaluation and Environmental Pollution

SESSIONE TS4.2

Risorse idriche e problematiche di inquinamento ambientale nell’area mediterranea

CONVENERS

Vaccaro Carmela (Università degli Studi di Ferrara) Riccardo Petrini (Università degli Studi di Trieste) Rosalda Punturo (Università degli Studio di Catania) Maurizio Polemio (CNR – IRPI Bari) Walter Dragoni (Università degli Studi di Perugia) Vincenzo Piscopo (Università degli Studi della Tuscia)

Rend. Online Soc. Geol. It., Vol. 21 (2012), pp. 847-848, 4 figs. © Società Geologica Italiana, Roma 2012

Amphibole asbestos and other fibrous minerals in the meta-basalt of the Gimigliano-Mount Reventino Unit (Calabria, South-Italy) ANDREA BLOISE (*), ELENA BELLUSO (**,°,+), TERESA CRITELLI (*), MANUELA CATALANO (***), CARMINE APOLLARO (*), DOMENICO MIRIELLO (*) & EUGENIO BARRESE (*)

Key words: Amphibole asbestos, fibrous minerals, meta-basalts

INTRODUCTION The study concerns the investigation of amphibole asbestos and other fibrous minerals contained in the meta-ophiolitic sequence belonging to the Gimigliano-Mount Reventino Unit (GMRU, Fig. 1). This consists of meta-basalts, meta-gabbros/metadolerites and serpentinites with a sedimentary cover made up of marble alternating with calceschists and quarzites (PILUSO et alii, 2000; LIBERI et alii, 2006). Some of these lithologies, called “green rocks”, quarried for

These are five minerals belonging to amphibole group (i.e., tremolite, actinolite, anthophillite asbestos, crocidolite, and amosite) and chrysotile, all having length > 5 µm, width < 3 µm and aspect ratio length/ width > 3. Owing to possible health problems due to asbestos fibre exposition, the works in the aforesaid quarries are regulated by the Italian law (DM 14/06/1996). The univocal distinction among asbestos and other fibrous minerals i) is not so easy because some mineral fibres can be mistaken for asbestos and vice versa and ii) it is very important because law demands the asbestos identification and quantification. Besides the Italian law (DM 18/03/2003) established to make a map of the asbestos presence in outcropping rocks. Previous studies on the asbestos presence are referred to quarries and no detailed observations on fibrous amphiboles and other kind of fibrous minerals have been made (e.g. the different varieties of amphiboles have not been discriminated and characterized). For this aim, mineralogical studies and detailed characterizations of the meta-basalts are currently being carried out by polarized light microscopy (PLM), XRPD, SEM/EDS, TEM/EDS, TG/DSC, XRF investigations. Preliminary results show that the most abundant minerals in

Fig. 1 – Geological map of the Northern Calabrian Arc and study area location.

using as building and ornamental stones (ZAKRZEWSKA et alii, 2008), excavated for road yards, can contain asbestos minerals. _________________________ (*) Department of Earth Sciences, University of Calabria. (**) Department of Earth Sciences, University of Torino. (***) Department of Physic, University of Calabria. (°) Institute of Geosciences and Earth Resources (CNR), Torino section, Torino. (+) NIS Centre of Excellence, University of Torino.

Fig. 2 – Secondary electron SEM image of actinolite asbestos. .

all meta-basalts rocks are (in order of decreasing abundance): chlorite, epidote, amphiboles (asbestos actinolite, asbestos tremolite and riebeckite), serpentines, albite, muscovite, calcite.

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86° CONGRESSO SOCIETÀ GEOLOGICA ITALIANA 18-20 SETTEMBRE 2012, ARCAVACATA DI RENDE (CS)

Titanite, magnetite and clay minerals were also detected, but in low amounts and not in all samples. Concerning the morphology, the amphibole fibres, when observed by SEM, appear thin, rigid and approximately 30 µm in length (Fig. 2). Amphiboles asbestos are typically intergrown with serpentine minerals and this makes difficult to evaluate the amount of each fibrous phase by SEM. TEM/EDS investigations show that amphibole asbestos display two main varieties: asbestos tremolite

Fig. 4 – TEM image of chrysotile fibres.

750 °C, respectively. These new knowledge, suitably deepened by further observations, can be used i) to identify eventually health hazard areas owing to amphibole fibres and other fibrous minerals presence, ii) to provide data for compulsory Italian mapping, iii) as markers of specific environmental conditions during amphibole asbestos and serpentine minerals formation.

Fig. 3 – TEM images of asbestos tremolite fibre.

(Fig. 3) and asbestos actinolite. A hundred single fibres have been measured using TEM images: their width ranges from 200 to 430 nm. As regards the serpentine minerals, chrysotile shows the classical cylindrical fibres (Fig. 4), antigorite is characterized by lamellar and fibrous shape, lizardite exhibits only plate-like morphology. The width of chrysotile fibres ranges from 40 to 340 nm, with an average value of 80 nm. TEM investigations revealed that chrysotile, asbestiform and massive antigorite and lizardite were found in order of decreasing abundance. Low amounts of polygonal serpentine were also detected in some samples. Finally, the DSC curve for meta-basalt samples showed the characteristic endothermic peaks of amphibole asbestos and serpentine minerals ranging from 900 to 1000 °C and from 600 to

REFERENCES LIBERI F., MORTEN L. & PILUSO E. (2006) - Geodynamic significance of ophiolites within the Calabrian Arc. Island Arc, 15, 26-43. PILUSO, E. CIRRINCIONE R. & MORTEN, L. (2000) - Ophiolites of the Calabrian Peloritan arc and their relationships with the crystalline basement (Catena Costiera and Sila Piccola, Calabria, Southern Italy) . GLOM 2000 Excursion GuideBook. Ofioliti, 25, 117-140. ZAKRZEWSKA A. M., CAPONE P. P., IANNÒ A., TARZIA V., CAMPOPIANO A., VILLELLA E. & GIARDINO R. (2008) Calabrian ophiolites: dispersion of airborne asbestos fibers during mining and milling operations. Periodico di Mineralogia, 77, 27-34.

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Rend. Online Soc. Geol. It., Vol. 21 (2012), pp. 849-850, 1 fig. © Società Geologica Italiana, Roma 2012

Monitoring of heavy metal pollution in soils and waters of a Domitian coastline (Northern Campania) M.M. CALANDRELLI (*) & R. CALANDRELLI (**)

Key words: Environmental pollution, heavy metals, site of national interest. INTRODUZIONE Soil is one of humanity's most precious assets. It allows plants, animals and man to live on the earth's surface (European Soil Charter, Council of Europe, 1972). Soil is a limited resource whose functions are numerous, from simple physical support for the construction of human settlements and infrastructures, based on food and feed production, timber and other materials useful to man. It is warehouse and source of raw materials and has the function of maintaining regional planning, as a key factor for slope stability and the groundwater and surface waters circulation. The soil has

also an important natural function as a habitat for a wide variety of plant and animal species as well as because the cycle of water and of other natural elements are completed in it. And, finally, it is an important element of the landscape that surrounds us and is part of our historical and cultural heritage (ARPAV). These two definitions sum up in few words the immeasurable ecological and environmental value that the soil resource features. The processes of environmental pollution lead to the alteration of the chemical-physical and biological equilibrium of the soil and predispose it to erosion and landslides as well as allowing the input of harmful substances in the food chain. In recent years considerable efforts have been made by the scientific community and Public Administration in order to understand the potential risks to humans and the ecosystem, caused by the presence of various contaminants. The presence of

Fig. 1 – Aerial view of the study area: Artificial lakes formed in old disused sand quarries are visible.

_________________________ (*) Institute of Agro-environmental and Forest Biology, CNR, Naples (** )Institute for International Legal Studies,, CNR, Naples

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these substances is generally associated with various human activities such as waste incineration, chemicals manufacturing, metallurgical and energy production, vehicular burning, etc. (SCAZZOLA R. et alii., 2000). The soil pollution by heavy metals is much more severe than that of air and water as pedosphere remains impaired for much longer, although the sources of contamination are removed. For the strict definition of pollution by heavy metals, it is essential to identify and quantify the forms under which they are present in pedosphere. The present paper describes the investigation activities on the ground areas of a territory falling within the SNI Domitian Phlegrean and Agro Aversano Coast. The objective of this study is to provide an assessment of the environmental status of the study area through the implementation of a plan for monitoring the state of soils with special regard to the presence of heavy metals in land and water areas. It summarizes the general characteristics of the study area and the history of the human activities undertaken over time that may have caused a hazard to the environmental matrices. The study focused on a portion of territory of about 30 acres occupied by two artificial lakes resulting from the reuse of disused quarries and areas adjacent to them where activities related to livestock farming and agricultural production are carried out. In order to ascertain whether such an use of the land has resulted in a significant change in the natural levels of heavy metals in soil, a study was necessary to assess the need of adopting measures for emergency securing (D.M. 471/99). The results of sampling and analysis activities are shown with the evaluation of non-compliance with law requirements (acceptable limit values of concentration in the soil, subsoil and

groundwaters). Aiming at supplying additional information on the environmental status of the study area, some pedological parameters were determined (granulometry, organic matter, pH) able to influence the processes of concentration of these contaminants in the soil. The determination of the concentration of heavy metals (Sn, As, Be, Cr, Pb, Zn) and the definition of their distribution on the land, through the creation of thematic maps in a GIS environment, enabled to acquire information on the extent and provided evidence to assume the source and mode of contamination of soils.

REFERENCES

CONSIGLIO D’EUROPA.,

(1972) – Carta Europea del suolo,

Strasburgo. MINISTERO DELL’AMBIENTE, (1999) D.M. 471/99, Regolamento recante criteri, procedure e modalità per la messa in sicurezza, la bonifica e il ripristino ambientale dei siti inquinati, ai sensi dell'articolo 17 del decreto legislativo 5/2/1997, n. 22, e successive modificazioni e integrazioni. Gazzetta Ufficiale della Repubblica Italiana.15 dicembre 1999, n.293. S.O. SCAZZOLA R., MASIA L., CAMPACI P., INGROSSO M., (2000) - Le procedure operative per la bonifica dei siti inquinati: modalità di applicazione del D.M. 471/1999 con il commento di casi pratici, Milano: Il sole 24 ore,. VI, 150 pp.

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Rend. Online Soc. Geol. It., Vol. 21 (2012), pp. 851-852. © Società Geologica Italiana, Roma 2012

A potential site suitable for CO2 geological storage in the Po Plain (Italy) D. CIVILE (*), M.F. LORETO (**), F. DONDA (*), V. VOLPI (*), E. FORLIN (*), M. ZECCHIN (*), B. MERSON (*), B. BOIARDI (°) & R. FANTONI (°) Key words: CO2 geological storage, Po Plain, Anticline. trapping mechanisms.

The Carbon Capture and Storage (CCS) technology has the potential to enable large reductions in global greenhouse gas emission by capturing the anthropogenic CO2 from various sources, such as coal-fired power plants or manufacturing industries, and by injecting the CO2 into deep geological formations like saline aquifers, depleted oil and gas fields and coal beds. OGS analyzed the late Messinian to Quaternary siliciclastic foredeep succession of a portion of the Po Plain in order to identify and characterize a potential site suitable for the geological storage, in deep saline aquifers, of the CO2 produced by a large industrial plant. This work, based on 21 composite logs and over 4500 km of 2D seismic lines, is the first detailed study carried out in this area. The analysis of data has allowed to identify an anticline located just beneath the plant that would represent an “ideal case” for the CO2 geological storage. The anticline developed for about 24 km and has a maximum width of 13 km for an areal extent of roughly 253 km2. This structure is slightly asymmetric, with a NE-vergence and a sub-vertical NNW-SSE trending axial plane. Two reservoir-caprock systems have been detected: - a deep system composed of a late Messinian sandy turbidite succession, having a thickness ranging between 350 m and 500 m and a porosity of 21-24%, sealed by lower Pliocene clayey deposits, about 150 m thick. - a shallower system composed of a thick Pliocene turbidite succession characterized by a 260-400 m thick sandy lower part with a porosity of 27-30%, and a 200300 m thick upper part containing several decametrescale pelitic layers. The anticline is not affected by faults that may represent potential ways for CO2 escape, and is located in an area characterized by very low seismicity, low heat flow (2,5°C/100 m) and hydrostatic pressure gradient in the analyzed _________________________ (*) Istituto Nazionale di Oceanografia e di Geofisica Sperimentale OGS, Borgo Grotta Gigante 42/c 34010 Sgonico (TS). (**) ISMAR, U.O.S., Bologna, Via Godetti 101 40129 Bologna. (°) eni e&p, Via Emilia 1 20097 San Donato Milanese (MI).

succession. All these conditions are essential for the assessment of the suitability of a site in terms of the application of the CCS techniques. A 3D geological model of the anticline has been made, allowing to obtain a volumetric model that has enabled to produce isopach maps of the two reservoirs and caprocks and to assess the anticline potential storage capacity (C). The storage capacity was calculated following the “volumetric method” proposed by the U.S. Department of Energy (2008): C= V*DCO2**Cs V= volume calculated by the volumetric model considering only the porous and permeable portion of the reservoirs located above the spill points; D = CO2 density at the reservoirs depth and under standard temperature and pressure conditions at the surface;  = porosity of the reservoir; Cs = coefficient of storage efficiency used for studies at site scale (0,2 and 0,4). The total volume potentially available for the CO 2 storage in the whole anticline is about 163 km3, i.e. 65,6 km3 for the shallower reservoir and 97,3 km3 for the deeper reservoir. The total available volume is strongly reduced down to 4,43 km3 (2,7 % of the total volume) considering the spill point position. Taking into account the last values of the reservoirs volume, the estimated storage capacity ranges from a minimum of about 162 Mt, considering the most cautionary storage efficiency of 0,2, to a maximum of about 324 Mt, using a storage efficiency of 0,4 (the highest value used for assessments to site scale). Considering that the current rate of CO2 emissions from the industrial plant is approximately 2,16 Mt/year, the CO2 produced by this plant may be stored for about 75 years in the first case and for about 150 years in the more optimistic hypothesis. These assessments consider only the structural trapping above the spill point, whereas others trapping mechanisms such as residual trapping, solubility trapping and mineral trapping have been not taken into account. Studies carried out by StatoilHydro for the Sleipner project in Norway (HERMANRUD et alii, 2009) have demonstrated that approximately 60% of the injected CO2 in saline aquifers, consisting of sand-clay alternations similar to those found in the studied anticline, is trapped below the structural spill point during the CO 2 plume migration. This is due to hydrodynamic trapping (i.e. due to the combination of CO2 solubility trapping in the brine, residual trapping and local stratigraphic and structural trapping) and mineral trapping. These considerations would support the

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hypothesis that the total storage capacity of the selected site may be considerably higher. In conclusion, the identified anticline represents an almost ideal case among the previously documented potential CO2 storage sites. In fact, the structure is located in an area characterized by very low seismicity, low heat flow and hydrostatic pressure gradient, and it is not affected by detectable faults. The anticline hosts two potential reservoircaprock systems, having considerable thickness and suitable petrophysical characteristics suitable for CO2 injection and storage. The only critical but not negligible aspect is the considerable depth of the two reservoirs (over 2000 m), which could complicate the injection operations. A very positive peculiar aspect concerns the position of the source of CO2 considered in this study that is located in correspondence of the axial zone of the anticline, providing the following advantages: 1) possibility to realize the CO2 injection system within the plant without additional costs for the creation of pipeline installation; 2) no CO2 will be produced in relation with its injection; 3) reduction of the possible discomforts/impacts caused to the population and to the

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surrounding environment; 4) an authorization process probably easier and faster. Finally, the preliminary assessment for the storage capacity has shown that, in the most precautionary hypothesis, the selected site would be able to store the CO2 produced by the industial plant for at least 75 years and considering only a structural trapping. Taking into account the CO2 stored by other trapping mechanism below and above the spill point during CO2 plume migration would allow to store higher amounts of CO2, that could be better defined by further fluido-dynamic modelling.

REFERENCES

HERMANRUD C., ANDRESEN T., EIKEN O., HANSEN H., JANBU A., BOLÅS H.N., SIMMENES T.H., TEIGE G.M.G. & ØSTMO S. (2009) - Storage of CO2 in saline aquifers: lessons learned from 10 years of injection into Utsira Formation in the Sleipner area. Energy Procedia, 1 (1), 1997-2004.

Rend. Online Soc. Geol. It., Vol. 21 (2012), p. 853. © Società Geologica Italiana, Roma 2012

ZeoLIFE, a project for water pollution reduction and water saving using a natural zeolitite cycle M. COLTORTI (*), D. DI GIUSEPPE (*), B. FACCINI (*), E. PASSAGLIA (°), D. MALFERRARI (°), M. MASTROCICCO (*) & N. COLOMBANI (*) Key words: zeolitites, nitrate pollution, water saving. ZeoLIFE project has been conceived to test an innovative integrated zeolitite cycle aimed at reducing the NH4+ content in livestock effluents and correct agricultural soils, with improvement of the yield and economization of water for irrigation and fertilizers, leading to a reduction of surface water and groundwater pollution and excessive exploitation of the water resource. Natural zeolitites are rocks containing more than 50% of zeolites, a kind of minerals with peculiar physical and chemical properties, like high and selective cation exchange capacity (CEC), molecular adsorption and reversible dehydration. Zeolitites are capable to uptake NH4+ from solutions and to release it gradually to the roots of the plants. The project proposes an open-field experimentation of an integrated zeolitite cycle, for 2 year of cultivation. It foresees the construction of a prototype tank for swine manure treatment, where an appropriate quantity of natural K-zeolitite (Italian chabasite zeolitite) will be added and mechanically mixed. The zeolitite will then be left still to reach cationic equilibrium with the manure: in a time span of 12-18 hours it will subtract by selective cationic exchange a considerable amount of NH 4+ from the liquid. The NH4+-charged zeolitite will then be removed and added to parcels of land, where it will release the nutrients only through cationic exchange induced by humic acids of plant roots and in proportion of the real needs of the cultures. A surface of about 6 ha will be divided into various parcels. Control parcels will be cultivated and irrigated in traditional way; other parcels will be added with natural zeolitites and one will be

mixed with NH4+-charged zeolites from the prototype tank. In the parcels amended with zeolitites both fertilization and irrigation water will be reduced by 30 and 50% respectively. A reduction of nitrate content in groundwater and surface waters is expected without any decrease of the yield. Prototype working parameters need to be estimated in order to optimize the production of NH4+-charged zeolitites to be put in the experimental fields. In bench scale reactors a series of experiments were performed to test the exchange capacity of natural zeolites in contact with the manure solution. Each experiment was performed in triplicate, each time varying one single parameter (mixing time, zeolitite/manure ratio, resting time). Over the whole duration of the experiment, samples of manure were taken from each of the reactor vessels at increasing time intervals, each sample were analyzed for NH4+ by ISE electrochemical sensor, for the quantification of the ammonium exchanged on chabasite. Results show that a zeolitite/manure ratio of 25 gr/l, a mixing time of 45 minutes and a resting time of 12 hours allow the zeolitite to take the maximum amount of ammonium from the solution, up to 30 mg/g. After zeolitite addition each parcel will be monitored by periodic groundwater and surface water sampling and by a series of permanent devices, installed before the beginning of experimentation. The permanent monitoring stations include: a piezometer for groundwater sampling, multiple lysimeters for interstitial water sampling, a datalogger for physical-chemical parameter monitoring and interstitial water quantification, and an evaporimeter. An automated meteorological station has been also installed in order to quantify rainfalls and sun irradiation for water balance.

_________________________ (*) Dipartimento Di Scienze della Terra, Università degli Studi di Ferrara. (°)Dipartimento Di Scienze della Terra, Università degli Studi di Modena e Reggio Emilia. Lavoro eseguito bell’ambito del progetto ZeoLIFE (Project LIFE+10 ENV/IT/00321), con il contributo finanziario dell'Unione Europea.

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Hydrogeochemical investigation and relationship between mineralogy and groundwater composition. A case study from the Sila Massif (Calabria, Italy) TERESA CRITELLI (*), CARMINE APOLLARO (*), ANDREA BLOISE (*), DOMENICO MIRIELLO (*), VINCENZA ARMANO & ROSANNA DE ROSA (*)

Key words: Gneisses, groundwaters, hydrogeochemical, Sila Massif.

INTRODUCTION The study focus on the geochemical characterization of a gneissic-metamorphic aquifer in the Sila Massif. The Sila Massif is a sector of the Calabrian Arc, or Calabrian Orogenic Wedge, a nappe-structured belt formed during the Alpine orogeny, preserving the oldest evidence of the ongoing subduction process of the Ionian oceanic slab, which lead (and still leads) to the consequent opening of the Tyrrhenian back-arc basin (FACCENNA et alii, 2004). In order to investigate the interaction between the gneisses cropping out in the study area and the local groundwaters, seventeen samples, were collected from both springs and well in Fig. 1). In the field, temperature, pH, Eh, alkalinity and electrical conductivity were determined by means of portable instruments. Groundwater samples were filtered in situ through a 0.4µm pore-size polycarbonate membrane filter although this method has some limitations because colloidal particles may pass through the filters (e.g., KENNEDY AND ZELLWEGER, 1974; LAXEN AND CHANDLER, 1982). In the laboratory, major dissolved anions and cations (Na+, K+, Mg2+, Ca2+, Cl-, SO42-, F-, NO3-) were determined by HPLC (Dionex DX 120), whereas Si and several trace elements were analysed by a quadrupole ICP-MS (Perkin Elmer/ SCIEX). Data quality for major components was evaluated by charge balance. Precision and accuracy for minor and trace elements was checked by measuring the certified reference material NIST-1643E. The mineralogy of the gneissic rocks, which has been examined using optical microscopy, X-ray diffraction and scanning electron microscopy (SEM) consists of quartz, plagioclase, garnet, biotite and sillimanite. Accessories include

Fig. 1 – Geological sketch map of the study area. The location of samples of water and rocks is also shown.

opaque, muscovite and cordierite (Fig. 2). All these data are in agreement with the results of a previous study by BERTOLANI AND FOGGIA (1975). The compositional features of water samples was characterized in terms of relative Cl, SO4 and HCO3 concentrations (Fig. 3a) and relative Na+K, Ca and Mg contents (Fig. 3b), all in equivalent units. In the triangular plot involving the three major anion (Fig. 3a) all the samples are

_________________________ (*) Department of Earth Sciences, University of Calabria Via Ponte Pietro Bucci, 87036 - Arcavacata di Rende (CS), Italy

Fig. 2 – Optical microscopy observations of thin sections(Pl=plagioclase; Bt=biotite, Grt=garnet; Ms=muscovite).

The P.h.D. of Teresa is co-financed by the Commissione Europea (FSE) and Regione Calabria (POR Calabria FSE 2007-2013).

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Fig. 3 – Triangular plot involving (a) HCO3-, SO42-, and Cl-, and (b) Ca2+, Mg2+, and Na++K+, both prepared from concentrations in equivalent units.

situated in the HCO3- field, indicating that the chemistry of local shallow groundwaters is chiefly dominated by conversion of CO2 to the HCO3- ion through water-rock interaction (GARRELS, 1968). In the triangular diagram involving the four major cations (Fig. 3b), most groundwaters are situated in the Mg2+-Ca2+ field, indicating that the Mg-Ca-HCO3 chemical composition of these springs is controlled by the dissolution of Mg-Ca-rich phases present in gneisses. According to this preliminary data, it was possible to conclude that the release of major dissolved constituents and several trace elements to shallow groundwaters is probably controlled by weathering of minerals rich in Mg and Ca such as plagioclase and biotite. The quality of groundwaters was investigated through the analyses of PHES (potentially harmful elements and species) such as Cr, Cd, Ni, U, As whose concentration are below the limits established by the guidelines of the World Health Organization for drinking water (W.H.O., 1993), so they do not pose a human health risk. In order to reconstruct a reaction path modeling, other investigations are still in progress.

REFERENCES BERTOLANI, M., FOGGIA, F. (1975) - La formazione Kinzingitica della Sila Greca. Boll. Soc. Geol. It., 94, 329345. FACCENNA, C., FUNICILLO, F., PIROMALLO, C., ROSSETTI, F., GIARDINI, D., FUNICIELLO, R. (2004) - Subduction and back-arc extension in the Tyrrhenian sea. Mem. Descr. Carta Geol. d’It. 44, 165-184. GARRELS, R. M. (1968) - Genesis of some ground waters from igneous rocks. In: Abelson, P.H. (Ed). Researches in Geochemistry 2, Wiley, 406-420. KENNEDY, V. C., ZELLWEGER, G. W. (1974) - Filter pore-size effects on the analyses of Al, Fe, Mn, and Ti in water. Water Resour. Res. 10, 785-790. LAXEN, D. P. H., CHANDLER, I. M. (1982) - Comparison of filtration techniques for size distribution in freshwater. Anal. Chem. 54, 1350-1355. W.H.O. (1993) - Guidelines for drinking-water quality. Vol.1: Reccomendations, 2nd ed. WHO, Geneva.

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Contribution to the knowledge of hydrogeological characteristics of plain S. Eufemia Lamezia (Calabria) - first results ENZO CUIULI (*)

Key words: acquifer, Drenage areas, graund water, groundwater divide, piezometric map, recharge areas This study aims to the knowledge of the hydrogeological characteristics of the Plain of San Eufemia Lamezia, focusing on 'superficial aquifer more susceptible to anthropogenic impacts, the depletion of water resources, and exploitation of that begun by the late twenties when the area, once marshland, was reclaimed making fitted for human’s settlement, development and farming. This study is based on the reconstruction and the subsequent comparison of piezometric maps of different years (1974, 1985, 1999, 2011) which embrace the time interval of the last forty years. The purpose is to provide a contribution to a better understanding of the superficial acquifer of the plane through the identification of the essential elements of last one, the schema definition of groundwater flow, an estimate of the depletion of groundwater. In general, the study area is part of the wider plain of S. Eufemia Lamezia, which is located in correspondence of the gulf, alongside the Tyrrhenian coast of central Calabria. In particular the studied area, of about 150 kmq, is enclosed, roughly, in a polygon whose vertices are the Capo Suvero (north) and Torre Mezza Praia (south) alongside the coast, the 'town of Lamezia Terme (North) and village Curinga (south) in the interior. At regional scale, the plain falls within the Tyrrhenian area of " Catanzaro’s Graben" which crosses the

central Calabria from east to west, cutting the mountains of Sila by Serre. This "Graben" is a tectonic structure of regional significance in the regional geological context of the Calabrian Arc (Amodio Morelli et al., 1976). The Graben is filled by Plio-Quaternary deposits, and was created by sub-vertical faults with a prevailing direction WNW - ESE with a component left lateral strike-slipe (Gulla et al., 2005). The rock types represented in the Structural-lithological map have been mainly determined on the basis from the Geological Map of Calabria (ex CASMEZ, 1967) and merged to derive the lithological types as homogeneous as possible. From lithological map was then derived the permeability map. To determine the structure of the superficial acquifer of S. Eufemia Lamezia plain, his relationships with surface water, and the changes experienced over time by the water resource have been reconstructed and compared piezometric maps of different years (1974, 1985, 1998, 2011). For the preparation of piezometric map, relating to 1974, was used “l’ Atlante delle carte isopiezometriche – Pr. Speciale 26" (CASMEZ 1977) showing, the piezometric line detected on 9/1974. For the preparation of piezometric map, relating to 1985, was conducted a deep literature research of previous studies (including unpublished) carried out in various ways by drilling companies, professionals, institutions.

Fig. 2 – Permeability map - plane of S.E. Lamezia

Fig. 1 – Structural – lithological map - plane of S.E.Lamezia. [litholocical base(CASMEZ, 1967), rid. e mod. Stuctural base (SORRISO – VALVO & TANSI, 1986) rid. e mod..]

_________________________ (*) Geologo –; [email protected]; [email protected]

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Fig. 4 – Piezometric map 1985 [ data base:previous study carrier out by drilling companies, professionals ecc.].

Fig. 3 – Piezometric map 1974 [ Pr. Sp. 26 (CASMEZ 1977) rid e mod.].

For the preparation of piezometric map, relating to 1998, it was used the study of Sappa & Bianchini (1999). For the preparation of piezometric map, relating to 2011, during the summer months, was recorded and noted the static level of groundwater in many wells of the plain in order to reconstruct the piezometric present.

Fig. 6 - Piezometric map 2011.

Fig. 5 - Piezometric map 1998 [piezometric map of Sappa & Bianchini (1999), rid. e mod.].

According to the study of the piezometric maps reconstructed, it outlines a pattern of groundwater flow, aquifer surface of the Plains of S. Eufemia, characterized by: A) Recharge Zone" of the aquifer located in the internal areas of the plain, near the foothills. These areas are distinguished by a high density of piezometric lines that present concave upward. The trend of the piezometric morphology suggests that in these areas there is a high hydraulic gradient, low transmissivity and low permeability. The flow lines are divergent and tend to flow towards the main axes of preferential drainage recognizable on map.

B) "Drainage areas" of the aquifer, represented by those areas, located downstream of the "recharge zone", and placed in the middle belt and the coastal plain. The “zones of recharge" are easily recognizable, on map, as characterized by a low density of isofreatic lines presenting concavity downwards and flow direction which tend to converge towards the axes of preferential drainage placed at the center of the isofreatic lines. This trend of piezometric morphology suggests that in these areas there is a low hydraulic gradient, high transmissivity and high permeability. C) "Groundwater divide" and "preferential drainage axes", as easily recognizable on the map, have been reconstructed basing on the interpretation of the isopiezometric morphology. The first being no flow horizons, influence the groundwater flow, the second representing the preferential flow paths of groundwater flow. On the basis of all these elements, identified through the reconstruction and interpretation of the isopiezometric surface, there has been a rapid assessment of the degree of depletion of the aquifer, in

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the time interval analyzed (1974 - 2011).Were draw, along the lines of maximum slope, three profiles of the piezometric surface with different color for each reference year.

deeper understanding of superficial acquifer. All the described elements, taken together or individually, find many applications in the study of the dynamics of depletion and pollution groundwater. The superficial aquifer of the plain, subject to human pressure and the related impacts, resulting susceptible to degradation qualitative and quantitative of water resources both in terms of depletion and in terms of pollution loads that potentially insist on the aquifer originating from the presence of settlements (point and diffuse), farming activities, industrial activities that insist in a large part of the study area.

REFERENCES

Fig.7- Piezometric profiles.

From these elaborate it’s shows that between 1974 and 2011, compared with an increase of water resources, clear in the case of upstream (corresponding to the internal areas - areas of recharge), there was a progressive decrease of water resources in stretches of valley profiles (corresponding to the outer areas / coastal - areas of drainage). The decrease of water resources is most evident in the south of the plain (profile [EF]) subject to the removal of more water. In this sector, of the study area, there is the industrial complex of Lamezia Terme-S. Pietro Lametino and areas of the plane, committed to farming (agricultural / zootechnics). The presence of these activities, together with the presence alongside the coast, tourist facilities and private houses, often also equipped with wells, likely this reduction of water resources in the coastal area against an increase in the quantity of water in internal recharging areas. The increase of the water resource in the recharging area is instead probably to search in a variation of the rainfall area. In conclusion, therefore, the present study, aims to contribute a

AMODIO-MORELLI L.,BONARDI G., COLONNA V., DIETRICH D., GIUNTA G., IPPOLITO F., LIGUORI V., LORENZONI S., PAGLIONICO A., PERRONE V., PICARRETA G., RUSSO M., SCANDONE P., ZANETTIN-LORENZONI E., ZUPPETTA A., (1976) ”L'arco Calabro-Peloritano nell' Orogene Appenninico Magrebide”; Mem. Soc. Geol. It., vol. 17, 160. ANTRONICO L., TANSI C., SORRISO-VALVO M., GULLÀ G. (2001) “Carta litologico – strutturale e dei movimenti in massa della stretta di Catanzaro ( sc.: 1:50.000)”; CNR – GNDCI, linea 2 – Previsione e prevenzione di eventi franosi a grande rischio, U.O. 2.56, (publ. 2119), SELCA – Firenze BURTON A. N. (1967) “Carta Geologica della Calabria” alla scala di 1:25.000; Cassa per il Mezzogiorno CASSA PER IL MEZZOGIORNO (1978) “Studio Organico Delle Risorse Idriche In Calabria, Atlante Delle Carte Piezometriche E Della Qualità Delle Acque” CASTANY G. (1963) “Traitè Pratique Des Eaux Souterraines”; Paris CELICO P., DE VITA P., MONACELLI G., SCALISE A.R., TRANFAGLIA G. (2005) “Carta Idrogeologica Dell’italia Meridionale” [scala 1:250.000]; Apat – Univ. Federico II Na; Ist. Polig. e Zecca Dello Stato Spa; Rm CELICO P., DE VITA P., MONACELLI G., SCALISE A.R., TRANFAGLIA G. (2007) “ Note Illustrative Della Carta Idrogeologica Dell’italia Meridionale” [Scala 1:250.000]; Apat – Univ. Federico II Na. Ist. Polig. E Zecca Dello Stato Spa; Rm CELICO P. (1986) “Prospezioni Idrogeologiche” VOL. 1 – 2; LIGUORI ED. NAPOLI CUIULI E. (2004). “Studio Dell’influenza Dei Caratteri Strutturali Sulla Geomorfologia Dell’area Compresa Tra Il Fiume Amato, Monte Contessa E Monte Covello (Calabria)”; Geologia dell’Ambiente, Periodico Trimestrale - Soc. It. Geol. Amb.). 4, Pp. 9 – 15 GULLA G., ANTRONICO L., SORRISO – VALVO M. & TANSI C. (2005) “ Proposta Metodologica Per La Valutazione di Indicatori di Pericolo e Rischio Frana a scala intermedia: L’area Della Stretta Di Catanzaro (Calabria – Italia)”; Geolog. Roman. Vol. 38, Pp. 97- 121

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MARIA MARI G., MOTTERAN G., SCALISE A R, TERRIBILI D., ZATTINI N., (1995) “Carta Idrogeologica D’italia – 1: 50.000 Guida Al Rilevamento Ed Alla Rappresentazione”; Quaderni Serv. Geol. Naz., Serie III, Vol. 5. Ist. Polig. e Zecca Dello Stato SPA, Rm. MIN. LL.PP. – SERVIZIO IDROGRAFICO (1941) “Le Sorgenti Italiane”; Publ. 14, 6, Ist. Polig. di Stato; Rm PANIZZA M. (1995) “Elementi Di Geomorfologia”; Pitagora Editrice, Bologna. RIGA G. (1985) “Dati Piezometrici Piana Di S. Eufemia Lamezia (Cz)”; INEDITI. SAPPA G., BIANCHINI B. (1999) “Caratterizzazione Idrogeologica della Piana Di S. Eufemia con l’ausilio di metodi termocoduttimetrici”; Ingegn. e Geol. degli Aquiferi, 13, 19 – 29; Torino. SOGESID (2009) “Piano Di Tutela Delle Acque Della Regione Calabria”; Pres. Cons. Dei Min. – Comm. Deleg. Emerg. Amb. in Calabria – Regione Cal.

SORRISO–VALVO M. & TANZI C. (1996) “Carta Delle Grandi Frane E Deformazioni Gravitative Profonde Di Versante Della Calabria”; Selca Firenze. SORRISO–VALVO M. & TANZI C. (1996) “Grandi Frane E Deformazioni Gravitative Profonde Di Versante Della Calabria Note Illustative Della Carta Al 250.000”; Geograf. Fis. E Dinamic. Quat. Vol. 19, Pp. 395 – 408. TORTORICI G., BIANCA M., MONACO C., TORTORICI L., TANSI C., DE GUIDI G., & CATALANO S. (2002) “Quaternary Normal Faulting And Marine Terracing In The Area Of Capo Vaticano And S.Eufemia Plain (Southern Calabria)”; St. Geol. Camerti – Nuova Serie 1/2002. TORTORICI L. (1982) “Lineamenti Geologico-Strutturali Dell'arco Calabro-Peloritano”; Soc. It. Min. Petr.,38, Pp.927-940. UNESCO (1970) “International Legend For Hydrogeological Maps”; Cook, Harmond & Kell Ltd.; England.

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Environmental geochemistry of Peat-rich sediments in the Po river Delta area (Mezzano lowland, Ferrara) DARIO DI GIUSEPPE (*), GIANLUCA BIANCHINI (*,**) CLAUDIO NATALI (*,**), LUIGI BECCALUVA (*)

Key words: geochemistry, Po river. This study is focused on the easternmost part of the Po river alluvial Plain in northern Italy, i.e. a sedimentary basin bordered by the Alps and the Apennines, which hosts about 30–40% of the Italian population and most of the Nation’s agricultural activities. In particular we investigated a specific sector of the Province of Ferrara known as “Valle del Mezzano” (45° 50’ 33’’ N and 12°05’40’’ E) hereafter reported as Mezzano low-land (MLL) that is included in the Regional natural park of the River Po Delta. The outcropping sedimentary facies (and the related soils) reflect climatic changes and human impacts that profoundly modified the configuration of the local drainage system, which is represented by the evolving Po river (AMOROSi et alii. 2002; BIANCHINI et alii 2002; STEFANI and VINCENZI 2005; SIMEONI and CORBAU 2009). In the easternmost terminal part of the basin the delta environment developed high lateral mobility of the active channel belts, permitting in historical times the development of fens and swamps characterised by peat deposition. When the high-energy alluvial deposition outranged the organic deposition, the peat levels were buried and incorporated into the stratigraphic record (MIOLA et alii 2006). Therefore it has to be noted that the MLL outcropping soils are significantly different from those recorded in the surrounding part of the plain (AMOROSI et alii 2002; BIANCHINI et alii 2002), as they evolve from saline sedimentary deposits peculiarly rich in peat material. This site specificity is also related to the geomorphological history of the area deeply influenced by anthropogenic activities: MLL was a marsh wetland since fifty years ago (see the 1944 geographic map of the area) and has been drained and reclamated in several stages mainly during the years fifties and sixties. Nowadays MLL is mainly 3-4 m below sea level and drained by hydraulic pumping and a system of artificial channels. The geochemical characterization of these deposits is very important taking into consideration that the local backgrounds of _________________________

elements potentially toxic exceed those recorded in other sectors of the Padanian plain (AMOROSI et alii, 2002; BIANCHINI et alii, 2002). This is possibly related to a remarkable role of the organic fraction in the metal complexation. The aim of this study is to evaluate possible geochemical risks of former wetland converted in agricultural areas, taking into consideration the nitrate pollution problem, as well as the potential bioaccumulation processes of heavy metals. The analyses reported in this contribution include a) nutrient evaluation (TOC, and nitrogen measured as extracted nitrates); b) XRF data carried out on bulk soils; c) tests of metal extraction with both aqua regia and EDTA that highlight the distinct elemental mobility; d) tests of bioavailability realized analyzing lattuce (lactuca sativa acephala) grown on the studied soils. This approach is useful provide guidelines for agricultural activities (i.e. mode and style of soil amendment and fertilization) and to evaluate possible geochemical risks, i.e. contamination of the local agricultural products by harmful elements in the food chain.

REFERENCES AMOROSI A., CENTINEO MC., DINELLI E., LUCCHINI F. &TATEO F. (2002) - Geochemical and mineralogical variations as indicators of provenance changes in Late Quaternary deposits of SE Po Plain. Sediment Geol., 151, 273-292. BIANCHINI G., LAVIANO R., LOVO S.& VACCARO C. (2002) Chemical–mineralogical characterisation of clay sediments around Ferrara (Italy): a tool for an environmental analysis. Appl. Clay Sci., 21, 165-176. MIOLA A., BONDESAN A., CORAIN L., FAVARETTO S., MOZZI P., PIOVAN S. & SOSTIZZO I. (2006) - Wetlands in the Venetian Po

Plain (northeastern Italy) during the Last Glacial Maximum: Interplay between vegetation, hydrology and sedimentary environment. Rev. Palaebot. Palyno., 141, 53-81. SIMEONI U., CORBAU C. (2009) - A review of the Delta Po evolution (Italy) related to climatic changes and human impacts. Geomorphology. Geomorphology., 107, 64-71. STEFANI M., VINCENZI S. (2005)

- The interplay of eustasy, climate and human activity in the late Quaternary depositional evolution and sedimentary architecture of the Po Delta system. Mar. Geol., 222-223, 19-48.

(*) Dipartimento di Scienze della Terra, Università degli studi di Ferrara, Via Saragat1, 44100 Ferrara, Italy (**) Istituto di Geoscienze e Georisorse, C.N.R., via Moruzzi 1, I-56124 Pisa, Italy

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Heavy metals in soils and sedimentary deposits from Vigarano Mainarda (Ferrara, Northern Italy): characterisation and biomonitoring DARIO DI GIUSEPPE (*), GIANLUCA BIANCHINI (*,**), CLAUDIO NATALI (*,**), LUIGI BECCALUVA (*)

Key words: alluvial sediments, biomonitoring, extration test, heavy metals, Padanian Plain. This contribution investigates agricultural soils from Vigarano Mainarda in the province of Ferrara (Padanian alluvial Plain, Northern Italy), in order to provide insights into their genesis, to define the geochemical background of the area and to evaluate the existence of anthropogenic contamination. Moreover, environmental risk related to the presence of potentially toxic heavy metals that can be transferred into agricultural products (and consequently bio-accumulated in the food chain) is assessed. The analyses, reported in an extensive supplementary dataset, include XRD, XRF, and ICP-MS data carried out on bulk sediments, tests of metal extraction with aqua regia, as well as analyses of local agricultural products, i.e. biomonitoring which is important in the evaluation of the element mobility. Based on the results, GIS-based geochemical maps were produced and local backgrounds were defined. This approach

demonstrated that a high concentration of Cr, Ni (Co, V) is a natural (geogenic) feature of the local alluvial terrains, which in turn is related to the origin and provenance of the sediments, as confirmed by the lack of top enrichment in all the investigated sites. Tests of metal extraction and analyses of agricultural products provide guidelines for agricultural activities, suggesting that extensive use of sewage sludge, industrial slurry and zootechnical manure (that are often rich in metals) should be minimised. The extended dataset reported in this paper shows that the agricultural terrains of the studied alluvial plain are not characterised by anthropogenic heavy metal pollution. In spite of the elevated natural background of Cr and Ni, most of the local agricultural products do not show significant evidence of biomagnification. Exceptions are represented by forage grass (alfa alfa) and corn (maize) that tend to uptake arsenic and nickel, respectively. This demonstrates that in agricultural areas, a geochemical risk assessment must include both soil and plant investigations.

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Ammonium and nitrate zonation below marsh agricultural soils DARIO DI GIUSEPPE (*), MICOL MASTROCICCO (*) , NICOLÒ COLOMBANI (*), BARBARA FACCINI (*), MASSIMO COLTORTI (*) Key words: groundwater qualy, inorganic nitrogen, marshes, permeabity, sediment heterogeneity.

The inorganic nitrogen leaching from agriculture can have a severe and long-lasting effect on groundwater quality and it can also affect surface water quality since the contaminated groundwater can be discharged into drains in reclaimed lowland territories, like in the Po river delta. These lands lye below the actual sea level, thus they are continuously drained by pumping stations which collect the water from a capillary distributed network of channels and ditches. A complicating factor in understanding and quantify the effective leaching of nitrogen from agricultural fertilizers is the background ammonium presence in the sub-soils, due to peat layers, which provide a natural source of organic nitrogen slowly mineralized into ammonium. This implies that the geochemical inventory of ammonium-bearing sediments in peaty soils and sediments has an important control for the future development of groundwater quality in these areas. To estimate the mass of inorganic nitrogen present within the unsaturated zone below agricultural fields, a 6 ha wide site was characterized with high resolution core depth profiles. Cores were analyzed for inorganic nitrogen content (nitrate, nitrite and ammonium) and for bromide, used as nonreactive tracer. The soils and sediments within the site are highly heterogeneous, since many sedimentological environments overlapped during the last few centuries, creating vertical and lateral facies heteropies. These

facies heteropies were reconstructed in a GIS environment via grain size analysis, soil organic matter content and detailed stratigraphic logs. The vertical distribution of inorganic nitrogen species is nitrate prevalent in the first meter of soil, where oxic condition prevailed (also induced by tillage and drains); ammonium is the major nitrogen species from 1 to 4 m below ground level. Where buried sandy sediments (paleochannels) are present beneath 1 m below ground level, nitrate can penetrate slightly deeper in the unsaturated zone. Nitrite is detected only in the oxic portion of the unsaturated zone, suggesting that denitrification takes place. Elevated ammonium, chloride and bromide contents are directly related with non-drained peaty sediments (lying below drains elevation), confirming their natural origin. Sharp vertical gradients were found between nitrate and ammonium/bromide, confirming that the recharge only affects the first meter of soil. The ammonium nitrogen inventory in the studied area is more than double with respect to nitrate nitrogen, and even two orders of magnitude higher than nitrite nitrogen. The impact of data quality and resolution on the derived inventory was investigated by varying the size of the considered subset of geological and geochemical data. We found that geological data resolution is less significant with respect to geochemical data. The large presence of ammonium-bearing sediments in these lowland territories makes very challenging to assess nitrogen pollution from agricultural activities, such as fertilizer spreading, but this natural source should be taken into account when groundwater monitoring campaigns are performed.

_________________________ (*) Dipartimento di Scienze della Terra, Università degli Studi di Ferrara, Via Saragt 1, 44100 Ferrara, Italy. Lavoro eseguito bell’ambito del progetto ZeoLIFE (Project LIFE+10 ENV/IT/00321), con il contributo finanziario dell'Unione Europea.

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SINTACS method application for assessing the inherent vulnerability of the Venafro alluvial plain aquifer ALBERTO DI LUDOVICO (*), CUCULO FEDELE (**), MARIA VITTORIA MAIORANO (*), MARIA PINA IZZO (**), ANNUNZIATA DI NIRO (**), PASQUALE COCCARO (***) & ALFONSO SCOCCA (*) Key words: Venafro alluvial plain, SINTACS method, aquifer vulnerability. ABSTRACT As part of the monitoring and study of groundwater bodies, the assessment of the degree of aquifers intrinsic vulnerability plays a crucial role, since it represents a fundamental moment in the planning of the proper management of land and groundwater resources. This study wants to propose the application of an analytical methodology in order to define the degree of vulnerability of Venafro alluvial plain aquifer, which plays a strategic role for the whole Molise Region, considering its geological and hydrogeological features and the importance of the socioeconomic agricultural activity that takes place therein. Among the various criteria developed in the field of vulnerability assessment of groundwater bodies, the choice fell on SINTACS method, applied with the procedure referred to in the GIS mapping overlays in order to allow modeling of the territory with the criterion of "finite element". The SINTACS methodology, primarily developed since the 90s, has been applied to the Italian territory, obtaining a considerable success from the technical-scientific viewpoint: several research institutions tested it in experiments, finding a good correspondence with the Italian climatic and hydromorfologic dynamics. These results, together with the acquired knowledge about the reasons that determine the groundwater flow and the aquifer potential, allowed to draw a sufficiently comprehensive outline of the main critical factors of the territory, which is essential in the planning of protective actions and mitigation of water resources.

related to industrial, urban, agricultural, and other activities. It is also related to the inherent vulnerability of the aquifer, that is the attitude of the aquifer to ingest and disseminate a pollutant. It depends on various factors, such as the depth of the aquifer, the presence or absence of soils which cause the self-purification, the connections between the water table and those streams that can act as receptors of polluting substances of the surface or can favour their intrusion in the groundwater. In this work we examined the Venafro plain aquifer, of which an intrinsic vulnerability map was produced using the parametric method SINTACS. The application of this method requires the discretization of the territory in a usually square grid. Within each unit cell forming the grid 7 parameters are considered, assigning each a score between 1 (minimum conditions for a vulnerability) and 10 (conditions of high vulnerability). Once it is defined for each cell the scores of the 7 parameters, a string of weights (a weight for each parameter), useful to give more or less importance to one or to another parameter, is applied to them depending on the hydrogeological context under consideration. The authors of this method have identified in particular 5 types of strings corresponding to as many contexts (cracked areas, Karstic areas, etc. ..). Summing together the scores of weighted 7 parameters and multiplying them by a context factor, the vulnerability index is obtained for each cell. The integration of the values thus obtained gives, for each grid, a numeric value that represents the inherent vulnerability of the related aquifer. These values, ranging from a minimum of 26 to a maximum of 260 points, are grouped into six classes of vulnerabilities, from "very low" to "very high".

GEOLOGICAL AND HYDROGEOLOGICAL SETTING SINTACS METHOD The pollution of groundwater, and therefore the degradation of their quality, depends not only on sources or centres of danger _________________________ (*) ARPA Molise – Agenzia Regionale per la Protezione Ambientale (**) Autorità di Bacino Interregionale dei Fiumi Trigno, Biferno e Minori, Fortore e Saccione. (***)Autorità di Bacino dei Fiumi Liri-Garigliano e Volturno.

The Venafro Plain is placed in a south-central Apennines area which is particularly complex from the geological-structural point of view. Actually it is placed in a transition zone between the Abruzzese-Campana platform and Molise Basin, a slope environment in which lithologic limestone-marl-siliceous materials were sedimented , as well as debris in the area of the platform (from the Cretaceous to Paleogene). The Venafro basin is a typical depression of tectonic origin, formed during the Apennine orogeny, which is directly caused by continental sedimentary series of lacustrine, fluvial and fluvial-

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lacustrine-marsh nature made of Holocene-Pleistocene alluvial deposits. The latter are mainly represented by lenses and levels interdigitated with sandy gravel, silty sand, and secondarily with gravel-clay loam with sparse pyroclastic levels. The Venafro flat elevation is between 150 m and 200 m above sea level and is made, in its central and southern portion, of a hydrological alluvial complex, while in its northern part is made of travertine; both parts are characterized by a mediumhigh degree of permeability. The area under study has a total extension of about 40 km2 and is bounded to the east by Volturno river, which also forms the natural border with the Campania Region. The water table of the Venafro floodplain aquifer (Figure 1) flows from NE to SW in the far north of Venafro, and from NW to SE in the southern part of the plain. The elevation of the water table is between 145 and 190 metres above the sea level. This water table, also considering the fundamental homogeneity of the land and the relevant permeability, shows figures of piezometric gradient that are characterized by a very reduced variability, equal to about 4.5 ‰.

saturated”, “type of coverage”, “hydrogeological characteristics of the aquifer”, “the aquifer hydraulic conductivity”, “slope of the topographic surface”. After generating the SINTACS data_GRID related to the seven parameters, using GIS Model_Builder it was possible to obtain the sum of the values and multiply each of them by a factor which is representative of the environmental characteristics of the area under study. The SINTACS rating decreases according to a hyperbolic

DATA PROCESSING AND SINTACS INDEX CALCULATION The entire study area was divided into Square Elementary Cells (EFQ) consisting of square grid with sides 25 meters long. Then, the appropriate score was attached to each EFQ and each

Fig. 2 – Example of GRID scores relative to the depth of the aquifer and the slope of the infiltration effective.

Fig. 1 – Piezometric pattern of Venefro plain.

parameter. The parameters for the vulnerability calculation index have been recovered from the development and reorganization of a data series already available and adequately validated. The seven key parameters are the “depth of the groundwater”, “depth to the effective infiltration”, “the effect of self-purification of non-

type decrease, proportionately to the increase of the depth, that is the increase of “not saturated” thickness; adopted values range between 10 and 1. In particular for the floodplains, the groundwater depth parameter, has an always high weight which is decisive in the final calculation of the SINTACS index. Low values of depth correspond to high scores that increase following the specific weight of the string, so determining a heavier impact on the vulnerability index. Similarly, an unsaturated capable of a strong mitigation action will give a low product even if the multiplier is high, while easily penetrable unsaturated will strongly increase the index of vulnerability.

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The final outcoming GRID is the final map of the inherent vulnerability of the aquifer: in it each cells corresponds to a score depending on the degree of vulnerability to which the area identified by the single EFQ is exposed. The numerical modeling carried out through the conceptual model SINTACS has allowed the drafting of the final report concerning the inherent vulnerability of the aquifer of the Plain of Venafro, expressed with a numerical index that allows a sufficiently objective evaluation. It is thus clear that the plain of Venafro shows two degrees of vulnerability: “high” and “very high”, respectively, related to areas located in its eastern and western sides, with two additional sub-zones showing a “very high” vulnerability in its NE and SW regions. Once an intrinsic vulnerability map is obtained, it is possible to overlay on it the centers of danger that are present in the area,

information regarding possible actions for the monitoring, the prevention of pollution’s episodes and the protection of groundwater, and offers also a first general assessment of the potential risk. The main purposes of the numerical and cartographic calculations related to the intrinsic vulnerability of aquifers are to provide specific interventions for prevention and protection, which can be carried out through the existing legal system or the introduction of new constraints (General Development Plans, Plans Basin, Water Protection Plans, etc ...), and supply the planner with accurate information about the land uses and management. The cartography of vulnerability aims, therefore, at reducing the risk of exposure of the targets like the environmental system oriented to future generations and to the directly exposed population, in connection with the monitoring of resources and the need to pursue the quality targets of the Water Bodies, as they have been established by the European and national legislation.

REFERENCES

Fig. 3 – Venafro flood plain vulnerability map.

and so draw a map of the risk of pollution, that is the degree of probability that a polluting phenomenon affect the groundwater.

CONCLUSIONS In the national environmental context the groundwater is a strategic resource both for the high quality and for the abundant availability. However, the vulnerability map provides useful

BONI C., BONO C., & CAPELLI G. (1986) – Schema idrogeologico dell’Italia centrale. In: Mem. Soc. Geol. It. 35, 991-1012. CIVITA M., DE MAIO M., FARINA M., ZAVATTI A. (2001) – Linee guida per la redazione e l’uso delle carte della vulnerabilità degli acquiferi all’inquinamento. Manuali e linee guida dell’ANPA, 4/2001, 99 pp. CIVITA M., SAPPA G., ZAVATTI A. (2004) – Una procedura di valutazione delle fonti di pericolo per le acque sotterranee. In: IGEA, 19/2004. CORNIELO A., DUCCI C., GUARINO P.M. (1999) – I rilievi carbonatici del Matese occidentale e la Piana di Venafro: idrogeologia ed idrogeochimica. In: Boll. Soc. Geol. It. 118, 523-535. COTECCHIA V. (1952) – Caratteri geo-pedologici della Piana di Venafro. In: Boll. Soc. Geol. It. 71, 69-82. DI LUDOVICO A., DE TULLIO L., BALANTE C., SASSI C., MARTONE R, & CARLOMAGNO C. (2008) – Monitoraggio e studio delle acque sotterranee della Regione Molise. In: Atti del Convegno – Acque interne in Italia: Uomo e natura. Accademia Nazionale dei Lincei 28 Marzo 2008. FESTA A., GHISETTI F., & VEZZANI L. (2006) – Note illustrative: carta geologica del Molise. Edita da Regione Molise – Presidenza della Giunta. TALLINI M., PETITTA M., & RANALLI D. (2000) – Caratterizzazione chimico-fisica e idrologica delle acque sotterranee del massiccio del Gran Sasso d’Italia: analisi statistica dei dati esistenti. DISTAT:– Università degli Studi dell’Aquila. Volume 9/2000.

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Relazioni tra la radioattività naturale e i lineamenti geologici nel territorio comunale di Caraffa (CZ) FOLINO GALLO MICHELE (*), PROCOPIO SALVATORE (*)

Key words: faglie, gas radon.

INTRODUZIONE Recenti studi condotti in alcune aree ad elevato potenziale sismogenetico della Calabria (Valle del Crati, Altopiano Silano ionico, Piana occidentale di Lamezia Terme), hanno dimostrato che le principali faglie attive sono caratterizzate da alti valori di concentrazione di gas radon nel suolo (TANSI et alii, 2005; FOLINO GALLO et alii, 2011). Gli stress tettonici attivi in un’area possono provocare variazioni nel tempo di alcuni parametri fisici. Numerosi studi riportati in letteratura hanno suggerito che le misure della concentrazione di radon nell’acqua e nel suolo, possono essere un valido strumento per la comprensione dei fenomeni geodinamici (THOMAS, 1988; KING et alii, 1996). Le caratteristiche chimicofisiche, tempo di dimezzamento e solubilità, consentono al radon di essere trasportato per notevoli distanze da liquidi trasportatori come l’anidride carbonica e l’acqua. Le faglie determinando un aumento considerevole degli indici di fratturazione delle rocce che attraversano, rappresentano una via di fuga preferenziale per i gas. Una mappa delle concentrazioni di radon nel suolo può fornire elementi utili a definire sia la geometria che il potenziale sismico delle faglie e il rischio ambientale derivante dalla maggiore probabilità di accumulo di radon negli ambienti confinati. L’approccio metodologico già sperimentato, è stato di recente riproposto per lo studio della radioattività naturale nel Comune di Caraffa. Il monitoraggio della radioattività naturale e del gas radon ha interessato l’intero territorio comunale attraverso la stima dei livelli di concentrazione di radon sia indoor che nel suolo. Il confronto tra gli elementi tettonici, i dati della sismicità e le misure di radon sembra confermare il trend regionale con buona correlazione tra l’andamento delle strutture tettoniche e la distribuzione delle concentrazioni più elevate di radon. ASSETTO GEOLOGICO Il radon, gas radioattivo che costituisce la frazione preponderante della radioattività ambientale, è naturalmente _________________________ (*) ARPACal - Dipartimento Provinciale di Catanzaro.

emanato dalle rocce che costituiscono la crosta terrestre. Esso deriva dal decadimento dell’Uranio-238, le cui tracce sono presenti in ogni tipo di suolo. Per tale motivo è fondamentale individuare le possibili vie di comunicazione tra il sottosuolo e la superficie (faglie e fratture). Infatti, il discreto tempo di dimezzamento (3,82 giorni) e la sua solubilità permettono al radon di essere trasportato per considerevoli distanze da gas o liquidi trasportatori, come l’anidride carbonica e l’acqua. Le faglie inducono un aumento considerevole degli indici di fratturazione delle rocce che attraversano, costituendo una via di fuga preferenziale per i gas (Fig.1). Da un punto di vista geologico, l'Arco Calabro rappresenta un thrust-belt prodotto dalla sovrapposizione, attuatasi tra il Cretaceo sup. ed il Paleogene, di una serie di unità costituite da rocce cristallino-metamorfiche paleozoiche e coperture mesozoiche, derivanti dalla deformazione di domini continentali ed oceanici. Durante l’Oligocene-Miocene Inferiore, le suddette unità sono

Fig. 1 – Schematizzazione della risalita del radon lungo faglie attive sovrascorse “in toto” sulle unità di piattaforma appartenenti alla catena appenninica, lungo overthrusts che mostrano attualmente vergenza NE (AMODIO-MORELLI et alii, 1976; TORTORICI, 1982). La Calabria Centrosettentrionale è attraversata da un sistema di shear-zones profonde (Fig. 2) che, dal Pliocene medio e fino a tempi recenti, ha disarticolato il complesso edificio a thrust che costituisce l’Arco Calabro con una tettonica di tipo prevalentemente trascorrente (VAN DIJK et alii, 2000; TANSI et

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alii, 2007; FERRANTI et alii; 2009, FOLINO GALLO M., 2011). In particolare, l’area di studio, corrispondente con il territorio comunale di Caraffa, si estende su un’area di circa 24,7 km² e ricade nel settore centrale del graben di Catanzaro. Quest’ultimo rappresenta orograficamente una depressione morfologica allungata in direzione E-W, delimitata a Nord dal Massiccio della Sila e a Sud da quello delle Serre (Fig. 2). Il graben di Catanzaro è strutturato da importanti faglie che mostrano piani sub-verticali caratterizzati da cinematismi prevalentemente normali con una componente di trascorrenza che talora può diventare predominante. In particolare, l’area di studio

MISURE DI RADON E CONFRONTO LINEAMENTI NEOTETTONICI

CON

I

I dati geologico-strutturali assieme ai caratteri della sismicità strumentale e storica, sono stati confrontati con le misure di radon indoor e nel suolo eseguite ed i risultati ottenuti sono di seguito descritti (Fig. 3). Per la misura della concentrazione del gas radon in aria sono stati impiegati dosimetri ad elettrete per lunga durata (long term), dischi di teflon carichi elettricamente montati su una camera di conteggio in plastica conduttiva tipo L. La tecnica di misura è denominata sistema E - Perm e si basa sulla rivelazione della radiazione α emessa durante il decadimento radioattivo. Dalla differenza tra il potenziale elettrico iniziale e quello finale è possibile determinare la concentrazione di attività volumetrica di radon in Bq/m3 presente in un determinato sito sfruttando la relazione [1]:

V  V f  [ 222Rn ]   i  C   H  C F  te 

Fig.2 – Mappa schematica con i principali lineamenti tettonici della Calabria settentrionale (VAN DIJK et alii; 2000, modificata).

è caratterizzata da un elevato rischio sismico ricadendo nell’area macrosismica del terremoto del 28 marzo 1783 - intensità alla sorgente pari a XI MCS, magnitudo equivalente pari a 7 (BOSCHI et alii, 1997). Infine, da un punto di vista litologico nell’area in esame affiorano depositi sedimentari di età Miocene-Pliocene Sup. Tali sedimenti sono rappresentati da una successione di depositi prevalentemente sabbiosi ed arenacei e una successione di depositi argillosi (Fig. 3). In questo quadro geologico articolato e assai evolutivo il radon può diffondersi più facilmente attraverso le fratture della crosta fino a raggiungere i piani interrati e seminterrati degli ambienti di vita, determinando un aumento delle concentrazioni di attività volumetrica e di conseguenza del rischio derivante dall’esposizione.

dove [222Rn] in Bq/m3 è la concentrazione di attività di radon in aria; Vi e Vf in Volt, il potenziale superficiale iniziale e finale dell’elettrete; CF in [(Volt m3)/(Bq giorno)] è il coefficiente di calibrazione; te in giorni è il tempo di esposizione, per questa indagine un anno solare suddiviso in due semestri; in Bq/m3 è la concentrazione di radon equivalente dovuta alla radiazione gamma; H adimensionale è il fattore correttivo per l’altitudine. Il lettore di potenziale impiegato per la lettura degli elettreti è un RadElec E-Perm. Alla fine del periodo di esposizione con i rivelatori passivi, sono state calcolate le concentrazioni di attività degli ambienti confinati e si è proceduto con l’individuazione dei punti per la misura della concentrazione del gas radon nel suolo. Il monitoraggio della concentrazione di radon nel suolo è stato realizzato impiegando una catena di misura formata da: un monitore tipo MR1 con un rivelatore a scintillazione, una cella di Lucas con una sensibilità di 0,0341 [cpm/(Bq/m3)] accoppiata ad un fotomoltiplicatore e una sonda in acciaio posta ad una profondità di 60 cm dalla superficie. La misura è stata effettuata con una modalità di esecuzione attiva, aspirando il radon con la pompa di aspirazione di cui è dotato il MRI e un flusso di 0,25 l/min e realizzando su ogni punto di misura, tre campionamenti per un tempo di conteggio complessivo di 30 minuti. Le misure sono state realizzate in condizioni atmosferiche stabili. I dati geologico-strutturali assieme ai caratteri della sismicità strumentale e storica, sono stati confrontati con le misure di radon indoor e nel suolo eseguite nel comune di Caraffa ed i risultati ottenuti sono di seguito descritti (Fig. 3). L’analisi dei dati presenta un territorio in cui la concentrazione media di radon negli ambienti confinati è di 87±2 Bq/m3, in sintonia con la media nazionale e non, con quella che annovera il territorio calabrese nell’intervallo tra 20 e 40 Bq/m3. Il valore massimo registrato è pari a 209±27 Bq/m3.

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Fig. 3 – Confronto tra le misure di radon indoor e in suolo e i principali caratteri geologici del territorio comunale di Caraffa.

La concentrazione media più importante registrata di radon nel suolo è pari a 35,1±0,8 kBq/m3, riscontrata al contatto tra le due diverse litologie affioranti. Tale contatto è marcato da un’importante struttura crostale che si estende per molti chilometri verso sud e potrebbe essere stata riattivata dal terremoto del 28 marzo 1783. Più in generale dal confronto tra le concentrazioni di radon misurate e la distribuzione della fagliazione quaternaria recente, si deduce, per quest’area, che i valori più elevati di radon si dispongono lungo gli allineamenti tettonici più recenti.

CONCLUSIONI Il lavoro sperimentale ha migliorato il quadro cognitivo sugli agenti patogeni del territorio. L’analisi dei dati presenta un territorio in cui la concentrazione media di radon negli ambienti confinati è di 87±2 Bq/m3, in sintonia con la media nazionale e non, con quella che annovera il territorio calabrese nell’intervallo tra 20 e 40 Bq/m3. Le misure sperimentali hanno confermato l’andamento tipico della distribuzione lognormale della concentrazione di attività del gas radon per ambienti indoor nei piani interrati, al piano di campagna e al primo piano. I dati presentati in questo lavoro hanno confermato una forte correlazione tra l’andamento delle concentrazioni di radon e l’assetto neotettonico. L’approccio sperimentato su questo territorio è senza dubbio una buona base per applicare il modello di acquisizione e l’analisi dei dati sulla restante parte della Regione Calabria ritenuta dai promotori della campagna nazionale radon del 1990 un territorio a basso rischio radon, ignorando quasi completamente le potenzialità dell’Arco Calabro. Esiste più di qualche elemento per considerare il territorio calabrese come un’area dove non è possibile sottovalutare in alcun modo il rischio radon.

REFERENCES AMODIO MORELLI L., BONARDI G., COLONNA V., DIETRICH D., GIUNTA G., IPPOLITO F., LIGUORI V., LORENZONI S. et al. (1976) L'arco Calabro-peloritano nell'orogene appenninico-magrebide. Mem. Soc. Geol. It., 17, 1-60. BOSCHI E., FERRARI G., GASPERINI P. et al., (1997) – Catalogo dei forti terremoti in Italia 461 a.C.-1990, Istituto Nazionale di Geofisica, SGA Roma, 644 pp., n.1 CD-ROM. FERRANTI L., SANTORO E., MAZZELLA M. E., MONACO C., MORELLI D. (2009) - Active transpression in the northern Calabria Apennines, southern Italy. Tectonoph., 476, 226–251. FOLINO GALLO M. – Caratteri neotettonici del bordo nordorientale dell’Arco Calabro (2011) - Tesi di Dottorato – Università della Calabria – Dipartimento di Scienze della Terra, 129 pp. FOLINO GALLO M., TANSI C., PROCOPIO S, MARTINI G. (2011) Concentrazioni di radon lungo strutture tettoniche attive in Calabria, (2011). Atti del Convegno Nazionale, Airp Reggio Calabria. KING, C-H., KING, B-S., EVANS, W.C. (1996) - Spatial radon anomalies on active faults in California. A. Geoch., 11, 497–510. TANSI, C., TALLARICO, A., IOVINE, G., FÒLINO GALLO, M., FALCONE, G. (2005) - Interpretation of radon anomalies in seismotectonic and tectono-gravitational analyses: the SE portion of the Crati graben (Northern Calabria, Italy). Tectonophysics, 396, 181– 193. TANSI C., MUTO F., CRITELLI S., IOVINE G., (2007) - NeogeneQuaternary strike-slip tectonics in the central Calabrian Arc (southern Italy). Journal of Geodynamics 43, 393–414. THOMAS D.,Geochemical precursors to seismic activity. (1988) Pure Appl. Geophys., 126, 241-265. TORTORICI L., (1982) - Lineamenti geologico-strutturali dell’Arco Calabro. Soc. It. Min. Petr., 38, 927-940. VAN DIJK J. P., BELLO M., BRANCALEONI G.P., et al., (2000) - A regional structural model for the northern sector of the Calabrian Arc (Southern Italy). Tectonophysics, 324, 267-320.

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Hydrogeological and geochemical assessment of some spring waters in the municipal area of Chiaravalle Centrale (Calabria, southern Italy) F. IETTO (*), N. CANTASANO (°), R. FROIO (°), E. INFUSINO (**), G. CALLEGARI (°) & M.G. CIPRIANI (°)

Key words: Langelier-Ludwig diagram, springs discharges, variability index; The aim of this work is the physical and chemical water characterization of seven spontaneous springs, used for drinking purposes by local people in the municipal area of Chiaravalle Centrale (CZ, Calabria, Italy). The study of these springs, within the upstream area of Beltrame catchment, has been conducted from September 2007 to August 2008 through analyses of the main physical parameters (hydraulic discharge, pH, conductivity and temperature) on a weekly basis and through collection of water samples performed on site on a monthly basis. The Beltrame basin (38°40'53,04'' N 16° 24' 41,04'' E) occupies the central-southern area of Calabrian Ionian side and it extends along the northern edge of Calabrian Serre upland. The survey area falls in the wide fan-shaped upstream area of the catchment conforming to an old lake, dating back to pleistocenic age, of which Beltrame river was its outlet (IETTO, 2000). The presence of this ancient lacustrine basin, located between 400 and 500 meters high, is strengthened by the occurrence of blanket debris not very sorted, enriched in a red earthy matrix, organized in fan deltas and covered by silty and arenaceous sediments of an obvious underwater deposit. These lithologies are typical of the basin valley in the western side of Chiaravalle Centrale’s area, and show a good groundwater flow. Below the Pleistocene sediments follows, stratigraphic unconformity, the crystalline metamorphic bedrock, belonging to the Polia-Copanello Unit (TORTORICI, 1982) and formed by granulite gneisses of Paleozoic age. The related permeability is, generally, low with an increase of its value in the more fractured areas. In the eastern edge of pleistocenic lacustrine basin and, particularly, near the municipal area of Chiaravalle Centrale, outcrops the Pliocenic depositional sequence of marine origin and is constituted, from the lower to the upper levels, by: basal conglomerates, clays, fine sands with clay and silt layers, sands and sandstones with calcarenitic _________________________ (*) Dipartimento di Scienze della Terra, Università della Calabria (CS). (**) Dipartimento Difesa del Suolo dell’Università della Calabria (CS). (°) Istituto per i Sistemi Agricoli e Forestali del Mediterraneo I.S.A.F.O.M. U.O.S. di Rende (CS).

layers. Therefore, the relative permeability is very variable, proceeding from the low values of clays to the high values of coarse-grained sediments. The study area has been involved in uplifting process of Serre mountain range, began in the early Pliocene and still going (GHISETTI, 1979; TORTORICI et alii, 1995), with subsequent development of a normal fault system. In the study area the normal fault alignments extend along a NW-SE and NE-SW directions, in accordance to (GHISETTI, 1979) and (TORTORICI et alii, 1995). The abundant groundwater flow, coming from the neighbouring crystalline metamorphic mountains, in the wide upstream area of the catchment, is highly conditioned by the pliopleistocenic terrigenous sequence, variously permeable, and by the tectonic features of the site. So, in the whole area, there are a lot of springs that originally were located in old lacustrine basin. In particular, amongst the seven springs analyzed: Bovalina, Gullì, Timpa and Caria are located close to tectonic faults (NESW direction), while the others (Mumuriana, Buzzucoli and Via) emerge in the plio-pleistocenic terrigenous sequence. It has been observed, by the comparative analysis of spring outflows and the rainfall data (recorded by the Chiaravalle Centrale pluviometric station), that the time lag of the related peacks varies from one to two months, particularly for the springs distinguished by greater flows as: Gullì, Buzzuccoli, Bovalina and Mumuriana. The temperature of the water samples ranges from 13.3 to 14.9 0C and show small seasonal fluctuations. A more pronounced thermic variation, of about 4 - 5 0 C, is recorded, only, for Bovalina spring that shows the same trend of atmospheric temperature. The analysis of spring discharges point out an overall homogeneity of the recession coefficients, with values 0.0220.000 S/cm typical of poor water from a qualitative point of view (PAPPALARDO G., RAPISARDA F., 2008a). In the deep aquifer the increasing of conductivity proceeds from the hinterland towards the coast, here the average values of conductivity is 1.000 S/cm cm but locally it can reach peaks of 5000 S/cm. The development of the characteristic relationships between the major ions showed the influence of the sea intrusion of the human activities on groundwater. The most significant data concerning the relationship between HCO3 -/Cl, the ratio is always less than 0.0010, and between SO4 - / Cl -