ASSESSMENT OF GROUNDWATER QUALITY OF OKO AND AMAOKPALA ENVIRONMENT, SOUTHEASTERN NIGERIA

Abstract

Groundwater serves as a major source of domestic water supply in many communities in southeastern Nigeria, including Oko and Amaokpala. However, increasing urbanization, poor waste disposal, agricultural practices, and geogenic processes have raised concerns regarding groundwater contamination. This study assessed groundwater quality in selected boreholes using heavy metal parameters. Four borehole samples (BH1–BH4) were analyzed for iron (Fe), cadmium (Cd), zinc (Zn), lead (Pb), copper (Cu), manganese (Mn), sodium (Na), and potassium (K), and compared against USEPA and NSDWQ standards. Results showed mean concentrations of Fe (0.2416 mg/L), Cd (0.0065 mg/L), Zn (0.4851 mg/L), Pb (0.0089 mg/L), Cu (2.0239 mg/L), Mn (0.0152 mg/L), Na (11.1258 mg/L), and K (7.1311 mg/L). Iron and cadmium exceeded NSDWQ limits in some locations, while copper exceeded recommended values in all sampled boreholes. Borehole 1 recorded the highest total concentration (40.8905 mg/L), suggesting localized contamination. The study concludes that although groundwater remains suitable for some domestic purposes, elevated concentrations of Fe, Cd, and Cu pose long-term health risks. Continuous monitoring and treatment are recommended.