INVESTIGATION OF QUALITY ATTRIBUTES OF SOIL AND GROUNDWATER IN BUNDU-AMA AND ENVIRONS, PORTHARCOURT SOUTHERN NIGERIA

Abstract

Anthropogenic activities (poor sanitary conditions, commercial and domestic wastes disposal) and saline water intrusion have become a major environmental problem which exposes the soil and groundwater within the environment to heavy metals and other contaminants. Geology and hydraulic conductivity of the soil collected from the study area were studied. Physico-chemical characteristics of groundwater collected from boreholes and hand dug wells were also determined. The hydraulic conductivity of the area was determined by making four pits at varying depths of 0.0 m,0.5 m,1.0 m,and 1.5 m,at four locations. Also,heavy metals in the soil at five different locations of the study area were determined at depths of 0.4 m and 0.8 m. Results of hydraulic conductivity shows a range of 1.50*10>-4 - 2.75 * 10>-4 m/s indicating high permeability which could aid the infiltration of harmful wastes to the groundwater and soil. Heavy metals (Cu,Cd,Pb,Zn) were detected in the soil at various depths. However,Chromium, Cr,was generally less than detectable limits. The pH of the borehole water analyzed are acidic while that of the hand dug well water analyzed fell within the WHO recommended standards. Electrical conductivity of the analyzed hand dug water fell above WHO recommended standards. This could be as result of saline water intrusion which is also a contaminant. From the analysis in the analyzed groundwater, cations(Mg2+,Na+,K+) fell within WHO recommended standards. Also the anions (Cl-,HCO-3,CO32-,SO42-,NO2-,PO43+) fell within WHO recommended standards. All the heavy metals in the analyzed groundwater samples fell within WHO and NSDWQ recommended standards, except lead (Pb) and cadmium (Cd) which fell above WHO and NSDWQ standards which is also an indication of contamination. Good sanitary condition, continuous monitoring of groundwater quality from time to time as well as improving the waste disposal method are recommended.