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In Ajao Estate, it is believed that poor quality of its groundwater is unconnected to the dislodging of wastewater into the environment by food- and wine-producing industries operating in the area. To ascertain this claim, the impact of this wastewater on microbiological and physicochemical quality of the groundwater was evaluated. Microbiological result of water samples revealed decrease in Staphylococcus aureus, Clostridium spp., Escherichia coli, etc. count from the industrial wastewater dislodging point. Groundwater samples collected from areas under the influence of industrial wastewater showed higher concentration of physicochemical elements than those outside the area of influence (control) except pH (5.96) and Cl (19.80 ppm), while in soil samples, reverse was the case. In groundwater samples, most of the physicochemical parameters were not within the permissible limit for drinking water except zinc (Zn) (0.214 to 1.660 ppm) which falls within World Health and Nigerian limit of 3.0 ppm. The degree of contamination/pollution of all the heavy metals in the soil samples were neither polluted nor contaminated, even though the contamination factor (CF) and geoaccumulation index (I-geo) of cadmium (Cd) was the highest in main soil samples and in control. Negative correlations exist between all the heavy metals in soil samples and those in groundwater except copper (Cu). Reasonable concentrations of all these heavy metals with the exception of manganese (Mn) were seen in the sample of industrial wastewater, suggesting that industrial wastewater may be one of the possible sources of their concentration in groundwater even though there might be other sources.

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The load bearing capacity of soils in Otukpa area of Benue state, Nigeria was evaluated by characterizing the geotechnical, geophysical and structural properties of the soil. The evaluation was necessary because aside the area holding good prospect for future increase in human population, sparsely distributed low-weight buildings in the area have cracks and other signs of failure. Remote sensing/GIS, geophysical and geotechnical approaches were integrated to achieve the objective. 2-D tomography and processed remotely sensed data confirmed the presence of areas of strength especially to the north. Stratigraphy of the northern portion consist of four layers; loose top soil (0-0.26m), compact clayey sand (0.26m-3.33m), dry clayey sand (3.33m-74.21m) and saturated clayey sands (74.21m-201.58m) While the stratigraphy in the south is slightly different; compact topsoil (0-1.2m), loose sand (1.2m-10.81m), compact sand (10.82m-19.71m) and compact clay sand (19.71m-56.03m). The plastic limit range from 11-17% with average specific gravity of 2.64g/cm3. Permeability ranges from 7.8×10−6m/sec to 3.36×10−4m/sec while volume compressibility under 250kN ranges from 7.27×10−5m2/kN to 1.3×10−4m2/kN and the rate of consolidation under 250kN is within 12.43 m2/year to 1.33m2/year. MDD peaks at 1.85g/cm3 at an OMC of 12.11% and is lowest at 1.67g/cm3 at an OMC of 11.99%. UCS ranges from 31-45kN/m2 while shear strength is between 258.81kN/m2 to 338 kN/m2. Due to the variability of engineering properties of soils, the southern part of the area is preferred for locating the buildings. Generally, careful foundation design in the area is necessary.