Assessment of groundwater quality, source identification, and health risk around oil and gas drilling sites

The production of oil and natural gas has recently played a significant role in boosting the economy. In this process, the discharge of industrial waste through activities like exploration and extraction operations cause elevated levels of dissolved chemicals, which severely degrade water sources and render them unsafe for human consumption. The aim of the present study was to evaluate the distribution of nineteen physicochemical parameters including heavy metals (pH, EC, TDS, TH, As, Cr, Cu, Ni, Pb, Zn, Ca2+, Mg2+, Na+, K+, Cl−, F−, SO42−, NO3− and HCO3−) in groundwater samples collected around oil and natural gas drilling sites and assess the knowledge gap for a sustainable and safe environment. Groundwater quality was assessed using various hydrogeochemical parameters and pollution indices such as the geoaccumulation index (Igeo), enrichment factor (EF), contamination factor (CF), degree of contamination (Cdeg) with principal component (PCA) and regression coefficient analysis to identify the collective contamination source. The potential ecological risk indices (PERI) and health risk assessments were made using exposure factors references from USEPA’s database. The major findings indicated the Piper diagram is predominantly characterised by the Ca–Cl type whereas, Gibb’s plot showed evaporation and rock–water interaction influencing groundwater chemistry. Water quality index (WQI) results indicated 2