A geoelectric investigation involving twenty-six vertical electrical soundings was carried out at Jos, Plateau State, North Central Nigeria. The survey was aimed at determining the structure of the underlying bedrock, as well as computing the transmissivity for the aquifer in the area. The basement geometrymapproduced from the results of the survey indicates that the bedrock is undulating lying at depths between 30 m to 6.5 m. There is evidence of faulting and fracturing within the area. Computation of aquifer transmissivity values based on the results obtained made it possible to demarcate regions with good ground water potential in the area.

Fourteen (14) characters from six (6) water samples collected from springs, ponds, and streams located in Lower Cretaceous sedimentary area of Afikpo Basin have been analyzed. These include pH, turbidity, conductivity, total dissolved solid, hardness, Fe2+, Ca2+, Mg2+, K+, NO3-, Cl-, SO4(2-), and Na+. These sediments, which are Turonian and Coniacian in age, are subdivided into two by a basic rock dyke. Results of the analyses show clearly that the Turonian sediments, intruded by dolerite, have net Fe2+, HCO3-, Ca2+, Mg2+, Mn2+, Cl-, and SO4(2-) concentration while those from the younger Coniacian sediment have net higher amounts of K+, Na+, and Mn2+. The overriding mafic minerals in the basic intrusive rock possibly led to higher leaching into ground water system near it. On the other hand, the presence of feldsparthic to kaolinitic sands of the younger Coniacian units led to higher K+ and Na+ matter in the water from these zones. The formations dip away from the older sediments. Concentrations of these characters are within acceptable drinking water standards by World Health Organization but noticeable anomalous zones for Fe2+, Mg2+, and Ca2+ are zones of basic rock suites. Areas with greater Na+ and K+ are traceable to sandy units. It is thus concluded that more analysis of surface, subsurface, and pond water samples can be utilized for minerals search and geological mapping. At this stage, it forms a veritable reconnaissance tool.

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Numerous particulates are released from the dumpsites in Owerri metropolis and later dispersed to other areas in the environment where they cause adverse health challenges to the inhabitants. To analyze the PM concentration, field measurements were carried out at seven major dumpsites in the Owerri Metropolis. Estimates of the possible health risks as the result of exposure to airborne particulate matter (PM2.5, PM10, etc.) were performed using the US Environmental Protection Agency human health risk assessment framework. A scenario assessment approach in which normal exposure and worst-case scenario were adopted for acute and chronic exposure periods for infants, children, and adults. The concentrations of PM 2.5 which ranged from 122.30-501.76 μg/m3 at the dumpsites exceeded the WHO 24hr annual mean maximum exposure limit. The Nigerian National Ambient Air Quality Standard allowable limit for PM10 was exceeded by most of the dumpsites. Hazard quotient > 1 was exceeded for PM 2.5 by nearly all dumpsites and is likely to cause health challenges. The results showed that under monthly conditions, both PM2.5 and PM10 concentration levels at the dumpsites have the potential to cause adverse health effects when for infants, children, and adults on acute or chronic bases. Actions should be taken to regulate such PM exposure and to raise public awareness for the inhabitants of the affected areas. In conclusion, regular monitoring is therefore needed to decrease the ambient particulate matter (PM) concentrations in the study area.

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