[01] Austin Chukwuemeka Okonkwo, Department of Geology and Mining, Enugu State University of Science and Technology, Enugu, Nigeria. [02] Gabriel Z. Ugwu, Department of Industrial Physics, Enugu State University of Science and Technology, Enugu, Nigeria.

The study investigates the levels, sources, distributions and mobility of some trace elements in the groundwater aquifers of the Middle Benue Trough. A total of eighteen (18) locations were sampled for this study. From the samples analyzed, the range and average concentration obtained are: Iron (0.01mg/l – 62.50mg/l, Average – 6.53mg/l), Manganese (0.03mg/l – 7.90mg/l, Average – 1.89mg/l), Lithium (0.02mg/l – 8.42mg/l, Average – 2.56mg/l), Barium (0.16mg/l – 97.40mg/l, Average – 21.65mg/l), Strontium (0.08mg/l – 129.7mg/l, Average – 25.05mg/l), Bromine (1.00mg/l – 13.18mg/l, Average – 3.21mg/l), Lead (0.02mg/l – 4.00mg/l, Average – 0.69mg/l), Zinc (0.02mg/l – 7.00mg/l, Average – 2.09mg/l), Arsenic (0.01mg/l – 5.40mg/l, Average – 1.06mg/l), Chromium (0.20mg/l – 0.34mg/l, Average – 0.25mg/l), and lastly Copper (0.21mg/l – 1.97mg/l, Average – 1.12mg/l). Their elemental concentrations were compared with that of WHO standard for drinking water. The level of the trace elements in most locations largely exceeds the WHO standard for drinking water. Possible sources are leachetes from dumpsite, abandoned mine pits with saline water and basinal brines. From the study, water for domestic use at locations sampled should be treated before use. Routine water quality analysis should be done.

Trace Elements, Basinal Brine, Groundwater, Middle Benue Trough

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