An Integrated Approach to Identify Water Resources for Human Consumption in an Area Affected by High Natural Arsenic Content

Abstract

This study concerns the occurrence of arsenic in the groundwater system of the Cimino-Vico volcanic area (central Italy), different parts of which are currently widely used for local drinking water supply and for irrigation. The system shows a complex groundwater circulation, including a continuous basal aquifer, discontinuous perched aquifers, groundwater flows at high altitude, and local interactions with rising thermal fluids. Data on arsenic contents in 250 water samples from springs and wells and in 68 samples from rock outcrops were measured and combined with already existing information. Results highlight that arsenic concentrations of groundwater are influenced by type of aquifer, groundwater flow path, arsenic content of the aquifer rocks, and interaction with fluids rising from depth. Waters circulating in the Vico volcanics, one of the prominent rock units of the area, have high concentrations of arsenic, both for the basal OPEN ACCESSWater 2015, 7 5092 and the perched aquifers. A large fraction of the waters associated with this rock unit have arsenic contents higher than 10 μg/L (82 percent for basal, 40 percent for perched). In contrast, waters circulating in the Cimino volcanics have lower arsenic contents: 30 percent of the basal and 10 percent of the perched aquifers have arsenic concentrations greater than 10 μg/L. Through an integrated approach, including leaching tests to investigate the arsenic behavior concerning the water-rock interaction and a geostatistical modeling of data, it has been possible to identify and tentatively quantify suitable water resources that have arsenic content not exceeding the quality standards for human consumption.

Uranium natural levels in water and soils: assessment of the Italian situation in relation to quality standards for drinking water

“…The volcano of Vico was active between 419 and 95 ka from present and developed through alternating explosive and effusive phases which have led to several pyroclastic deposits and lava flows of phonolitic, tephritic and trachytic composition (Locardi 1965;Mattias and Ventriglia 1970;Bertagnini and Sbrana 1986). The rocks and soils of the area, in addition to the known high concentrations of arsenic (Armiento et al 2015), show a high average content in other elements including uranium.…”

“…The high concentrations of uranium in the area are associated with high content of other elements, e.g. arsenic (Armiento et al 2015) and beryllium (Armiento et al 2012), and are also documented by the presence of abandoned uranium mining sites. During the exploration activities for uranium research carried out starting from the late 50s, the territory comprising the volcanic complexes of the Northern Latium and Southern Tuscany was classified as ''uranium area'' and the uranium-related deposits were estimated as of subeconomic importance.…”

Sustainable Yield of a Hydrothermal Area: From Theoretical Concepts to the Practical Approach

“…In addition to the provisions of the regional legislation concerning agricultural or zootechnical activities, building, productive or commercial activities, disposal of water or civil waste, the drilling of wells and pumping from existing shallow wells are forbidden. Protection zone (PZ) is aimed at safeguarding the quality and quantity of the thermal water resources of the entire HAV. The boundaries of the PZ have been defined considering: (1) location of thermal springs (currently active or in the past) and shallow wells with water temperature > 21 °C and electrical conductivity > 1250 μS/cm; (2) distribution of travertine outcrops genetically related to thermal waters; (3) uplifted area of the sedimentary substratum of the volcanic rocks; (4) areas where hydrochemical indicators show significant mixing of the SA waters with thermal waters (such as sulfate, strontium and arsenic content in the SA waters; e.g., Baiocchi et al ; Armiento et al ); (5) areas of heat‐flow anomaly; (6) hydrographic network fed by thermal waters. For the PZ the following restrictions are applied: morphology and land‐use changes are forbidden, closing and sealing of wells with water temperature > 21 °C and electrical conductivity > 1250 μS/cm, absolute ban on drilling new wells and excavation works.…”

Anomalous concentrations of arsenic, fluoride and radon in volcanic-sedimentary aquifers from central Italy: Quality indexes for management of the water resource

“…fluoride; Vivona et al, 2007;Preziosi et al, 2016), ii) occurrence of toxic contaminants (e.g. arsenic and heavy metals; Angelone et al, 2009;Baiocchi et al, 2013;Armiento et al, 2015;Cinti et al, 2015;Viaroli et al, 2016), and iii) anomalous concentrations of radioactive isotopes (e.g. radon; Cinti et al, 2013).…”

“…As far as the study area is concerned, a few geochemical maps on the As spatial distribution, though limited to the VCVD, were published by Vivona et al (2007), Angelone et al (2009), Armiento et al (2015) and Cinti et al (2015) whereas maps related to the distribution of F À (Vivona et al, 2007;De Rita et al, 2011;Preziosi et al, 2016) and 222 Rn (Cinti et al, 2013) were poorly constrained. To fill this gap, in this paper spatial distribution maps of As, F À and 222 Rn concentrations, based on a large and original dataset consisting of 659 water samples collected in the SVD and VCVD, are shown and discussed to i) investigate the sources and the main factors controlling their geochemical behavior and distribution and ii) evaluate the contribution of these pollutants due to the geogenic source.…”