GROUNDWATER QUALITY STATUS AND HYDROCHEMICAL VULNERABILITY AROUND THE SURJAGARH OPENCAST IRON ORE MINING BELT, GADCHIROLI DISTRICT OF MAHARASHTRA (INDIA)

Abstract

Groundwater quality in mineral-rich hard-rock regions is strongly influenced by natural water–rock interaction, terrain conditions, and land-use disturbance associated with mining activity. The present study assesses groundwater quality status and hydrochemical vulnerability around the Surjagarh opencast iron ore mining belt using hydrochemical parameters, BIS drinking-water comparison, district-background comparison, and station-wise vulnerability classification. The analysis focused on selected parameters including pH, electrical conductivity, total dissolved solids, total hardness, calcium, magnesium, chloride, sulphate, bicarbonate, sodium, iron, uranium, and total alkalinity. Results showed that groundwater in the study area is generally near-neutral to mildly alkaline, with pH ranging from 7.00 to 8.70. Electrical conductivity indicated moderate dissolved ionic load, while total hardness and magnesium emerged as the dominant groundwater-quality concerns. Total hardness exceeded the BIS acceptable limit in 77.9% of analyzed records, and magnesium exceeded the acceptable limit in 61.0% of records. Calcium and TDS showed localized exceedance, whereas chloride, sulphate, and iron remained within permissible limits. Vulnerability classification indicated that most records fall within moderate to high vulnerability classes. The study identifies hardness, magnesium, localized calcium, and TDS as principal contributors to groundwater-quality vulnerability and emphasizes the need for systematic groundwater monitoring around the Surjagarh mining belt.