Anthropogenic Influences on the Hydrogeochemistry and Water Quality of Ground Water in Singrauli Power Belt Region, Central India

Abstract

Abstract:

This study investigates the groundwater quality of Singrauli power belt region in Eastern India. Groundwater samples were collected from 54 representative sites during pre and post monsoon seasons and analysed for pH, EC, TDS, TH, major ions (Na²⁺, K⁺, Mg²⁺, Ca²⁺, SO4^2-, NO₃^-, F^-, Cl^-)and heavy metals (Fe, Cr, Mn). Results suggested that groundwater samples dominantly belonged to Ca-Mg-HCO₃ group. Gibbs ratios indicated that rock weathering is the major driving force controlling the groundwater chemistry. Ca²⁺, Mg²⁺, Na⁺, K⁺, HCO₃^-, Cl^-, SO₄^2- concentrations in the groundwater were well within the permissible limits recommended by WHO for drinking water. A total of 35.2% and 44.4% of the samples had F- concentrations exceeding their WHO recommended limits of 1.5 mg/l during post and pre monsoon season, respectively. Likewise, a total of 22.3% and 26% of the samples had exceeded their regulatory limits of NO₃^- i.e. 45 mg/l during post and pre monsoon seasons, respectively. High fluoride concentration nearby fly ash ponds indicated contamination from the ash leachates. The high NO₃^- concentrations could be attributed to the formation of nitrogen oxides during coal combustion, their deposition on the surface and subsequently leaching to groundwater. The majority of samples had Fe and Cr concentration exceeding the WHO permissible limits, thus rendering water unfit for drinking purpose. Parameters like percent sodium (%Na), electrical conductivity (EC), sodium adsorption ratio (SAR), residual sodium carbonate (RSC), magnesium hazard (MH) permeability index (PI), chloroalkaline indices (CAI) and Kelly’s index suggest that majority of groundwater samples were good for irrigation purpose. The USSL plot suggested that majority of groundwater belonged to C₃S₁ class, representing high salinity hazard and low alkali hazards water, which requires proper drainage otherwise it, can adversely affect the soil.

 Keywords: Hydrogeochemistry, Major Ions, Heavy Metals, Fluoride, Nitrate