Aquifer protective capacity and groundwater quality investigations around some open dumpsites were conducted along New Road Sapele, Delta State. Nine Schlumberger arrangements of vertical electrical soundings (VES) were carried out with a maximum electrode separation of 500 m, and obtained data were interpreted by partial curve matching and computer iteration using Win Resist software. 2D survey using nine dipole-dipole stations was also utilized to give resistivity map of the dumpsites, while standard laboratory methods were used to analyze the groundwater. The study shows four to five geoelectric sections. The aquifer is within the third, fourth, and fifth layers at a depth of 30 m. The overburden protective capacity from the total longitudinal unit conductance indicates that VES 1 and 5 are adequately protected with protective capacity of 0.7 to 0.9 mhos, VES 2, 3, 6, and 7 are moderately protected with conductance values of 0.2 to 0.69 mhos, VES 4 is weakly protected with values of 0.12 mhos, and VES 8 and 9 are poorly protected with values of 0.003 to 0.004 mhos. In the 2D imaging, VES 4, 8, and 9 show contaminant presence to the depth of 20 m while VES 3, 6, and 7 show contamination to a depth of 50 m. However, the aquifer shows good transmissivity, an indication that if it is contaminated, the contaminants will circulate the aquifer at a high rate. The groundwater flows in the northeast (NE) direction, thereby recharging river Ethiope. The study also shows the presence of lead (0.01 mg/l), nickel (0.02 mg/l), and cadmium (0.03 mg/l), which made it unsafe for drinking and use in other life-related activities. Groundwater should hence be sourced from a depth of about 45–50 m in order to tap from the uncontaminated aquifer.

Twelve vertical electric soundings (VES) were carried out using the Schlumberger configuration with a maximum current electrode separation of 350 m using Abem Terrameter SAS 1000 AB in Issele Uku, Delta State, Nigeria, to determine the aquifer characterization of the area. The field data were analyzed by curve matching and computer iteration, and hydraulic characteristics of the aquifer were determined using the Dar Zarrouk parameters. The transmissivity of the aquifer varied from Trmax = 208.32 m2/day to Trmin = 109.2 m2/day. The knowledge of aquifer transmissivity made it possible to demarcate the area with good groundwater potential for setting-up boreholes in Issele Ukwu. The results show that the aquifer was not protected because of poor longitudinal conductivity due to the absence of clay. The results of water analyses reveal that water obtained from the various locations was safe for drinking, and other domestic and industrial purposes compared with the World Health Organization Standard.

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Supply of potable water in Oghara communities in particular and parts of Ethiope West Local Government Area of Delta State in general is inadequate as a result of increasing population and development activities in the area. This can be resolved and sustained if groundwater resources are effectively managed. This study was carried out to determine the aquifer vulnerability and groundwater quality using geophysical and physiochemical methods in parts of Ethiope West Local Government Area, Delta State. Thirty vertical electrical soundings and four dipole–dipole profiling were administered using Abem Terrameter SAS 1000 AB. The field data were curve matched and iterated using WinResist and Dipro software. The aquiferous zone was found in the fourth layer with resistivity ranging from 159 Ωm to 100234 Ωm, thickness ranging from 12 m to 156 m, and depth ranging from 32 m to 162 m except VES 25, whose aquifer is in the third layer. The dipole–dipole resistivity structure shows low resistivity values along areas where waste dump was sited with resistivity ranging from 300 Ωm to 630 Ωm. This finding suggests that the leachate from the dumpsite is affecting the characteristics possessed by the subsurface close to it. The first order geoelectric and Dar-Zarrouk parameter study of aquifer protective capacity revealed a protection capacity value less than 0.1 for VESs 1–18 and 20–30, while VES 19 revealed a value of 0.24. Thus, Oghara communities are extremely unprotected, and the aquifer is prone to contamination. The physiochemical analysis carried out indicates that groundwater is slightly acidic with a pH value ranging from 5.40 to 6.40 when compared with the WHO permissible limit. The groundwater flow direction is depicted from the east to the west; this will assist policy planners to decide where dumpsites and companies generating waste could be sited to preserve groundwater potential.