Groundwater vulnerability to pollution assessment: an application of geospatial techniques and integrated IRN-DEMATEL-ANP decision model

Abstract

This study evaluated the susceptibility to groundwater pollution using a modified DRASTIC model. A novel hybrid multi-criteria decision-making (MCDM) model integrating Interval Rough Numbers (IRN), Decision Making Trial and Evaluation Laboratory (DEMATEL), and Analytical Network Process (ANP) was used to investigate the interrelationships between critical hydrogeologic factors (and determine their relative weights) via a novel vulnerability index based on the DRASTIC model. The flexibility of GIS in handling spatial data was employed to delineate thematic map layers of the hydrogeologic factors and to improve the DRASTIC model. The hybrid MCDM model results show that net recharge (a key hydrogeologic factor) had the highest priority with a weight of 0.1986. In contrast, the topography factor had the least priority, with a weight of 0.0497. A case study validated the hybrid model using Anambra State, Nigeria. The resultant vulnerability map shows that 12.98% of the study area falls into a very high vulnerability class, 31.90% falls into a high vulnerability, 23.52% falls into the average vulnerability, 21.75% falls into a low vulnerability, and 9.85% falls into very low vulnerability classes, respectively. In addition, nitrate concentration was used to evaluate the degree of groundwater pollution. Based on observed nitrate concentration, the modified DRASTIC model was validated and compared to the traditional DRASTIC model; interestingly, the spatial model of the modified DRASTIC model performed better. This study is thus critical for environmental monitoring and implementing appropriate management interventions to protect groundwater resources against indiscriminate sources of pollution.

Application of geochemical tracers for the investigations of groundwater resources in semi‐arid region (Central‐East Tunisia)

“…According to Haied et al (2021), many studies have shown the importance of the correlation between natural and/or anthropogenic pollution and the vulnerability model. Recently, some models have been used in order to assess the groundwater vulnerability to pollution, such as the DRASTIC model (Chukwuma et al, 2023; Haied et al, 2021; Liang et al, 2016). Previous works, which are related to the Mahdia‐Ksour Essef aquifer study, used the DRASTIC model (Nasri et al, 2021; Saidi, 2011) in order to investigate the groundwater vulnerability.…”

“…According to Chukwuma et al (2023), the groundwater resources is important to all life forms, whether for human beings, animals or plants. Their importance is mainly manifested by their use as valuable water resources especially for drinking purposes (Narsimha & Wu, 2019) and for livestock farming and irrigation purposes (Skevas, 2020).…”

Flood Risk Assessment Basing on Flood Flow Modeling in the Oued Martil Region, Western Part of Northern Morocco

“…Geomorphometric properties [Ghasemlounia and Utlu, 2021]. For this purpose, several methods have been used, such as Morphometric analysis (MA) approach [Meshram et al, 2022 [Yariyan et al, 2020;Chukwuma et al, 2023], are utilized as techniques to identify areas with a high potential for producing floods. This study suggests using a hydrological study approach for Oued Martil and its tributaries, ranging from Oued Khémis to the river mouth, in response to the challenges associated with flood mapping in the study area.…”