Physicochemical Properties and Heavy Metal Concentration of Groundwater in Owerri Metropolis, Nigeria
E. C. Ogoko *
National Open University of Nigeria, Plot 91, Cadastral Zone, Nnamdi Azikiwe Express Way, Jabi, Abuja, Nigeria
*Author to whom correspondence should be addressed.
Abstract
The present study was performed in order to assess the physicochemical parameters and metal concentration of groundwater in Owerri municipal area. Water samples were collected in triplicates from thirteen different sites. Electric conductivity, pH, total dissolved solids, turbidity, biochemical oxygen demand, oxygen demand and chloride were determined by standard methods. Sulphate and nitrate were determined by UV- Spectrophotometric method whereas the metals were evaluated using Atomic Absorption Spectrophotometer (AAS). The results of the study revealed that both the physicochemical and metal parameters evaluated were within the limits recommended by WHO and SON. But arsenic concentration in one (Sample 6) out of the thirteen borehole sites had a pollution index above unity (1.11). The groundwater samples assessed were suitable and potable for drinking and other domestic purposes except water from site 6 (Egbu) which was contaminated with arsenic. Results also revealed that there is significant difference between the physicochemical parameters and the metals concentrations evaluated.
Keywords: Pollution index, contamination, atomic absorption spectrophotometer, metals, concentration