An example of aquifer heterogeneity simulation to modeling well-head protection areas

Groundwater management requires the definition of Well-Head Protection Areas (WHPA) for water supply wells. Italian law uses geometrical, chronological and hydrogeological criteria for WHPA identification, providing a groundwater travel time of 60 days for the definition of the Zone of Travel (ZOT). An exhaustive ZOT delineation must involve numerical modeling of groundwater flow together with simulation of the advective component of the transport process. In this context, the spatial variability of hydrogeological and transport parameters has to be critically estimated during numerical modeling implementation. In the present article, geostatistical simulation using a transition probability approach and groundwater numerical modeling were performed to delineate WHPAs for several supply wells in the middle Venetian Plain, taking into account the lithologic heterogeneity of the aquifer. The transition probability approach for the lithologic data was developed by T-PROGS software, while MODDLOW-2005 and PEST-ASP were used, respectively, to reproduce and calibrate site-specific hydraulic head data. Finally, a backward particle tracking analysis was performed with MODPATH to outline the 60-day ZOT

Geostatistics as a tool to improve the natural background level definition: An application in groundwater

The Natural Background Level (NBL), suggested by UE BRIDGE project, is suited for spatially distributed datasets providing a regional value that could be higher than the Threshold Value (TV) set by every country. In hydrogeochemically dis-homogeneous areas, the use of a unique regional NBL, higher than TV, could arise problems to distinguish between natural occurrences and anthropogenic contaminant sources. Hence, the goal of this study is to improve the NBL definition employing a geostatistical approach, which reconstructs the contaminant spatial structure accounting geochemical and hydrogeological relationships. This integrated mapping is fundamental to evaluate the contaminant's distribution impact on the NBL, giving indications to improve it. We decided to test this method on the Drainage Basin of Venice Lagoon (DBVL, NE Italy), where the existing NBL is seven times higher than the TV. This area is notoriously affected by naturally occurring arsenic contamination. An available geochemical dataset collected by 50 piezometers was used to reconstruct the spatial distribution of arsenic in the densely populated area of the DBVL. A cokriging approachwas applied exploiting the geochemical relationships among As, Fe andNH4+. The obtained spatial predictions of arsenic concentrationswere divided into three different zones: i) areas with an As concentration lower than the TV, ii) areas with an As concentration between the TV and the median of the values higher than the TV, and iii) areas with an As concentration higher than the median. Following the BRIDGE suggestions, where enough samples were available, the 90th percentile for each zone was calculated to obtain a local NBL (LNBL). Differently from the original NBL, this local value gives more detailed water quality information accounting the hydrogeological and geochemical setting, and contaminant spatial variation. Hence, the LNBL could give more indications about the distinction between natural occurrence and anthropogenic contamination

Conceptual and numerical models of a tectonically-controlled geothermal system: a case study of the Euganean Geothermal System, Northern Italy

The Euganean Geothermal Field (EGF) is the most important thermal field in northern Italy. It is located in the alluvial plain of the Veneto Region where approximately 17*106 m3 of thermal water with temperatures of 60–86 °C are exploited annually. A regional-scale conceptual model of the Euganean Geothermal System is proposed in this paper using the available hydrogeologic, geochemical and structural data for both the EGF and central Veneto. The thermal water is of meteoric origin and infiltrates approximately 80 km to the north of the EGF in the Veneto Prealps. The water flows to the south in a Mesozoic limestone and dolomite reservoir reaching a depth of approximately 3,000 m and a temperature of approximately 100 °C due to the normal geothermal gradient. The regional Schio-Vicenza fault system and its highly permeable damage zone act as a preferential path for fluid migration in the subsurface. In the EGF area, a geologic structure formed by the interaction of different segments of the fault system increases the local fracturing and the permeability favoring the upwelling of the thermal waters. Numerical simulations are performed to validate the proposed conceptual model using a finite difference code that simulates thermal energy transport in hydrothermal systems. A specific configuration of thermal conductivity and permeability for the formations involved in the thermal system is obtained after calibration of these parameters. This set of parameters is verified in a long-term simulation (55,100 years) obtaining a 60–70 °C plume in the EGF area. The modeled temperatures approach the measured temperatures of 60–86 °C, demonstrating that this conceptual model can be realistically simulated

Subsoil geostatistical modeling as tool for hydrogeological modeling: transitional probability approach applied upon a heterogeneous site

Hydrogeological modeling, 3D simulation, Venice lagoon, reactive transport numerical mode

Sustainable Co-Design with Older People: The case of a Public Restorative Garden in Milan (Italy)

The demographic aging and the evolution of lifestyles require new strategies to promote the well-being and active aging of elderly. Active aging depends on many factors: some of these are related to objective data such as physical environment, others are personal elements; it is important to improve environmental physical factors to encourage personal attitudes to the green spaces in use. To design a small sustainable restorative green space in Milan, Italy, restorative garden design criteria are summarized in the first section of the paper and both social and environmental sustainability are considered. The methodology section describes the co-design process and how it was applied to include dierent older user groups in the design of the area. In the results section authors apply a taxonomy based on the four properties of restorative settings according to the Attention Restoration Theory by Kaplan (compatibility, being away, extent, fascination): this provides a unified system to classify users\u2019 expectations and to describe the final project. The proposed co-design process combines social and environmental sustainability, as it provides designers an insight about the user\u2019s experience in nature. Such information can be fruitfully integrated with professional competences about comfort aspects and environmental protection in order to improve the whole design project

Fault Control on a Thermal Anomaly: Conceptual and Numerical Modeling of a Low\u2010Temperature Geothermal System in the Southern Alps Foreland Basin (NE Italy)

The interest on low\u2010temperature geothermal resources is progressively increasing since their renewability and widespread availability. Despite their frequency, these resources and their development have been only partially investigated. This paper unravels the major physical processes driving a low\u2010temperature geothermal resource in NE Italy (Euganean Geothermal System) through conceptual and numerical modeling. Dense fracturing associated to regional fault zones and a relay ramp enhances regional to local flow of thermal waters. Their rapid upwelling in the Euganean Geothermal Field is favored by open extensional fractures deforming the relay ramp. The water (65\u201386 \ub0C) is intensively exploited for balneotherapy, rendering it a profitable resource. Three\u2010dimensional coupled flow and heat transport numerical simulations based on this conceptual model are performed. Despite the presence of a uniform basal heat flow, a thermal anomaly corresponding to field observations develops in the modeling domain reproducing the relay ramp. Intensive fracturing extending across a wide area and a slightly anomalous heat flow favors a local increase in convection that drives the upwelling of deep\u2010seated hot waters. The simulations corroborate and refine the conceptual model, revealing that water of up to 115 \ub0C is likely to be found in the unexplored part of the thermal field. This study furthers knowledge on fault\u2010controlled low\u2010temperature geothermal resources where the geological setting could enhance local convection without anomalous heat flows, creating temperatures favorable for energy production. Conceptual and numerical modeling based on solid geological and hydrogeological reconstructions can offer a support tool for further detailed explorations of these prominent resources

Thermonanomechanics of Graphene Oxide-M13 Bacteriophage Nanocomposites -Towards Graphene-based Nanodevices

The self-assembly of graphene oxide (GO) and M13 bacteriophage results in the formation of micro-porous structures, known as GraPhage13 aerogels (GPA). Given the limited applications of aerogels in industry due to their nanomechanical properties, along with the previously observed temperature-dependent characteristics in graphene-based nanocomposites, a thorough exploration of the thermosensitive nanomechanical properties of GPA is essential. Herein, a comprehensive characterisation of the morphology, composition, and spectroscopic analysis of the GPA for a range of temperatures has been conducted and correlated with its nanomechanical properties. Elevated temperatures have been found to lead to gradual removal of oxygen-containing functional groups (OCFGs) from GPA, resulting in increased structural defects and reduced stiffness. Notably, unique nanomechanical behaviours of GPA have been further identified, where the thermal expansion of sp3 bonds exceeds that of a crystalline sp3 structure, while the thermal contraction of sp2 bonds in GPA is found to be between graphite and GO. This underscores the impact of GO functionalisation on the thermal expansion behaviour of GPA. The obtained insights enhance the overall comprehension of the temperature annealing impact on GPA and highlight the tunability of its nanomechanical properties, showcasing a broad potential of this novel nanocomposite across a diverse range of applications

Unravelling the importance of fractured zone in regional fluid flow: insights from the hydrothermal modelling of the Euganean geothermal system (ne Italy)

Euganean Geothermal System, fault system, 3D coupled flow and heat transport numerical model