A Grey Water Footprint Assessment of Groundwater Chemical Pollution: Case Study in Salento (Southern Italy)

Abstract

Abstract:The worsening of groundwater quality is a huge problem for some regions, especially where a karst aquifer system is the most important water resource because of the deficiency of a well-developed superficial water supply. In this study the chemical quality of a deep aquifer of the Salento peninsula (Southern Italy), where a shallow aquifer and an extensive deep aquifer are exploited as a source of drinking water and irrigation water, was monitored. The indicator used to assess the sustainability of pollution produce by human activities is the "grey water footprint" (GWF) which measures the amount of water required to assimilate a polluting load produced from anthropic activity. The GWF, calculated for each chemical parameter, shows a widespread contamination by Mercury (Hg), Vanadium (V) and Ammonium (NH 4 + ) with concentrations above the limits (Lgs. D. 31/2001). The high Mercury and Vanadium concentrations may thus be associated with anthropic pressures on the aquifer, while Ammonium derives mainly from fertilizers used in agriculture. The situation that emerged involves reflections on the continuous human pressure on natural resources. Therefore, the management of groundwater quality requires a multidisciplinary approach focused on identifying the measures necessary to protect our water resources.

Managing Water Sustainability: Virtual Water Flows and Economic Water Productivity Assessment of the Wine Trade between Italy and the Balkans

“…The amount of water required to assimilate a polluting load produced from crop production, bringing back the water quality to its allowable standard, represents instead the grey water footprint [31,76] and is equal to: The concept of virtual water is different from that of the water footprint. The former refers to the water volume embodied in a product, while the latter also captures other aspects, such as the localization and the source of water used.…”

Estimation of Conservative Contaminant Travel Time through Vadose Zone Based on Transient and Steady Flow Approaches

“…Reliable determination of contaminant travel time in an unsaturated zone (also known as an unsaturated time lag) is required to assess groundwater vulnerability to pollution, to plan monitoring and remediation activities and to predict the effect of changes in climate or land use practices on groundwater quality [1][2][3]. While the susceptibility of aquifers to pollution can be quantified using different approaches, like the index methods (e.g., DRASTIC [4,5]) or the grey water footprint method (GWF) [6,7], methods which explicitly take into account the time scale of contaminant transport are often preferable [3]. For the purposes of travel time estimation, it is often assumed that the dissolved pollutant behaves as a conservative substance; for example, it does not undergo any chemical or biological reactions and is not sorbed on the soil skeleton.…”

The Water Footprint Assessment of Electricity Production: An Overview of the Economic-Water-Energy Nexus in Italy

“…The WF approach considers the place where water is consumed, the type of water used and when it is used. In fact, WF measures can be computed for given areas, regions or even for nations and can be divided into three different components: the blue fraction, which refers to the use of fresh surface water or groundwater; the green fraction, which indicates the use of water derived from precipitations on land that do not feed the runoff or recharge of groundwater, remaining temporarily on the surface of vegetation [35]; and finally the grey fraction, representing the volume of freshwater necessary to dilute pollutants to such a level that the ambient water quality remains above a given quality standard [36].…”