HYDROGEOCHEMICAL ASSESSMENT OF GROUNDWATER QUALITY: A CASE STUDY OF MOSOGAR COMMUNITY

ABSTRACT Groundwater serves as the primary source of potable water for domestic use in Mosogar Community, Delta State, Nigeria; however, its quality is increasingly threatened by both natural and anthropogenic influences. This study carried out a hydrogeochemical assessment of groundwater from seven strategically selected locations comprising hand-dug wells and boreholes across the community. Physicochemical parameters, major ions, nutrients, and trace metals were analyzed in accordance with APHA (2017) and WHO (2017) standards to evaluate the suitability of the groundwater for domestic consumption. Results indicate that pH values (6.10–7.50) reflect slightly acidic to near-neutral conditions, while temperature (26.2–29.5°C), electrical conductivity (145–890 µS/cm), and total dissolved solids (85–505 mg/L) all fall within acceptable drinking-water limits, suggesting low mineralization and predominantly fresh groundwater. Major anions, including chloride (5.6–68.2 mg/L), sulphate (2.4–34.1 mg/L), and nitrate (0.8–26.3 mg/L), were also below WHO thresholds, indicating minimal influence from sewage infiltration, agricultural runoff, or industrial activities. Major cations such as calcium (5.8–72.3 mg/L), magnesium (3.2–31.4 mg/L), sodium (4.7–84.6 mg/L), and potassium (2.1–23.3 mg/L) were within permissible limits, reflecting geogenic sources dominated by silicate and carbonate mineral dissolution. Trace metals showed slight elevation of iron in a few locations (up to 0.87 mg/L), while cadmium, zinc, and nickel remained within acceptable limits. Low-level total hydrocarbon content (0.02–1.24 mg/L) suggests minor petroleum-related influence typical of the Niger Delta. Hydrogeochemical facies interpretation revealed that most samples belong to the Ca–Mg–HCO₃ type, indicating dominance of carbonate weathering and ion-exchange processes. Overall, the groundwater in Mosogar is largely suitable for domestic use, though localized iron enrichment and trace hydrocarbon presence necessitate periodic monitoring and improved sanitary protection of wells. The study provides essential baseline data for groundwater management and public health planning within the community.