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Trace metal concentration in soils of Iyara area of Warri, Delta State was studied using geophysical and geochemical techniques. Eight vertical electrical sounding (VES) using SAS 1000 Terrameter with maximum current electrode spread of 150 m in the Schlumberger configuration was carried out. The geoelectric layers obtained are topsoil, clay, sand and fine-medium grained sand. The fine to medium grained sand of the third and fourth layers mainly constitute the aquifer with a depth ranging from 4.8 - 11.0 m. Soil samples were collected at three of the VES stations covering the dumpsite and stations away from the dumpsite. The trace metal content was higher than the maximum allowable levels in soils as specified by the World Health Organisation (WHO) and Department of Petroleum Resources of Nigeria (DPR) except for Pb with undetected concentration in VES 3, Mn with 135 mg/kg in VES 1 and undetected in VES 3 and VES 7. The Multiple pollution index, Enrichment factor, and Non-carcinogenic hazard decreases with increasing distance from the dumpsite. The soil around the dumpsite has been impacted and the results of this study will serve as background information for soil studies and groundwater development in the area.

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Geostatistical analysis has been applied in the investigation of groundwater contamination in three dumpsites and a Control site in Warri and its environs in Southern Nigeria. This was to map the impact of contaminant emanating from indiscriminate dumping of domestic and industrial wastes on groundwater in the area. Sixteen (16) VES stations were occupied in the three dumpsites and the control site studied using the Schlumberger configuration. From each of the site, water samples were collected from boreholes, hand dug wells, and swamps, close to VES stations for chemical analysis and statistical evaluation using multiple regression analysis and Two-way Analysis of Variance (ANOVA). Aquifer resistivity ranges from 15 Ωm to 215 Ωm in the dumpsites area, and 336 to 884 Ωm in the control site. Hydrogeochemical analysis of water samples showed values of parameters that are higher around the dumpsites when compared to the control site, with the results for conductivity, nitrates, iron, lead and total viable bacteria count exceeding the standard permissible limits. A correlation of aquifer resistivity and hydrogeochemical analysis parameters show that resistivity of groundwater is significantly related to its physico-chemical properties with a contribution of 49.2 %. Also, at the significant level, P<0.05, the contribution, R 2 value (0.513) show that 51.3% of the presence of Total Viable Bacteria Count is attributed to groundwater resistivity in Warri and its environs.