Mapping grounwater vulnerability for pesticide pollution: a literature review

Aquifer pollution vulnerability defines the sensitivity of a groundwater body of being adversely affected by an imposed contaminant load (Foster et al. 2002). This concept entails two notions: intrinsic and specific vulnerability. Intrinsic vulnerability defines the vulnerability of groundwater to contaminants generated by human activities, depending on the inherent geological, hydrological and hydrogeological characteristics of an area (soil type, topography, recharge, vadose zone, etc.), but independent of the nature of contaminants. For specific vulnerability, specific physico-chemical properties from contaminants are considered (Gogu and Dassargues, 2000). Groundwater pollution risk can be defined as the process of estimating the possibility that a particular event may occur under a given set of circumtances (Voudouris, 2009) and the assessment is achieved by overlaying hazard and vulnerability (Gogu and Dassargues, 2000; Uricchio et al,2004). Several approaches exist for assessing groundwater vulnerability. They can be grouped into methods based on the use of (1) process-based simulation models, (2) statistical models and (3) overlay and index methods (Al-Hanbali and Kondoh, 2008; Gogu and Dassargues, 2000; Farjad et al., 2012; Mimi et al., 2011). Alternatively, they can be classified according the degree of integration of monitoring data in the vulnerability assessment (Vanclooster et al., 2014). Hence, distinction can be made between vulnerability assessment methods based on generic data, based on groundwater monitoring data, or hybrid methods based both on monitoring and generic data