Identifying the Sources of Contaminants in Groundwater Within the Alluvial Region Between two Perennial Rivers of Central Gujarat: Fid-Bau Portal

Identifying the Sources of Contaminants in Groundwater Within the Alluvial Region Between two Perennial Rivers of Central Gujarat

Modi, Mukesh A. / Shrimali, N. J.

Abstract

This research is mainly focused on identifying the sources of groundwater contaminants present in the alluvial region between Mahi and Narmada rivers of central Gujarat using multivariate statistical analysis. Furthermore, Ground Truth Study (GTS) will be conducted to determine the source of these contaminants and ascertain whether they type from anthropogenic (caused by human activities) or geogenic sources. In the study area, shallow depth of groundwater varies from 9.54–97.45 feet below ground level (fbgl). Using Principal Component Analysis (PCA), Factor Score Analysis and Hierarchical Cluster Analysis (HCA), 50 aquifer openwells and shallow tubewells have been analyzed using PCA, Factor Score Analysis, and Hierarchical Cluster Analysis (HCA). The PCA revealed 3 significant components explaining 77.15% of total variance in which PC-1 (43.04%) described high positive loadings of (TDS, NO₃⁻, Cl⁻, SO₄²⁻, Mg²⁺) parameters. The PC-2 (16.11%) and PC-3 (18%) showed high positive loadings of (F⁻, ALK) and (pH, TH, Ca²⁺) parameters. The application of Hierarchical Cluster Analysis (HCA) revealed the presence of distinct clusters influenced by either anthropogenic or geogenic sources. Notably, Clusters 3 and 4 exhibited substantial anthropogenic influence, emphasizing the urgency for immediate remediation measures. Cluster 2 demonstrated a combination of geogenic and anthropogenic sources, underscoring the importance of continuous monitoring in this area. In contrast, Cluster 1 represented relatively non-polluted regions, serving as valuable reference points. The findings emphasize the necessity for targeted mitigation strategies to safeguard groundwater resources, particularly in highly contaminated Cluster 4. Additionally, the inclusion of a Ground Truth Study (GTS) further enhanced the accuracy and reliability of the findings, providing corroborating evidence to support the identification and characterization of contamination sources within these clusters.