MONITORING OF GROUNDWATER QUALITY IN A SEMI-ARID REGION, TEBESSA BASIN (NORTH-EAST OF ALGERIA): USING POLLUTION INDEX OF GROUNDWATER

Abstract

The study area is characterized by low rainfall and a significant outcrop of salt formations, which significantly compromises the use of water for consumption and other purposes (agriculture and industry). Groundwater contamination affects both water quality and human health. Hence it is essential for continuous monitoring of the quality of groundwater so that contamination can be minimized. Application of pollution index of groundwater (PIG) to the problem of estimating groundwater contamination with respect to their drinking water quality standards has been done by the investigation of 58 water sample. The computed values of Pollution Index of Groundwater (PIG) for the study area vary from 0,457 to 8.190. Spatial variation map has been prepared using GIS.  The variation map shows that most of the study area accounts for high and very high pollution zones, which is mainly due to geogenic, anthropogenic factors and also it is compounded due to mining activities. Geochemical ratios (Na⁺: Cl^-, HCO₃^- : Cl^-, Na⁺: Ca²⁺ and Mg²⁺: Ca²⁺) also form the quantitative basis of the index. This manuscript synthesizes a set of data that allowed us to make a classification of the contamination zones, using PIG tool, of the study area.