We present a detailed physicochemical, bacteriological and hydrogeochemical results on representative water samples from eight boreholes and two hand-dug wells in Fufore area, northeastern Nigeria with a view to evaluate groundwater suitability for irrigation and drinking as well as ascertain their hydrogeochemical characteristics. In the area, only BH3 and BH7 yielded low acidic pH (5.0 and 5.8) which can corrode plumbing faucets, hence may cause adverse health effect (e.g. acidosis). Aside that, all the other physical parameters such as temperature (average = 29.71), EC (average = 424.26 µs/cm) and TDS (average = 191.68 mg/l) agree well with their respective standard for irrigation. Similarly, majority of the physicochemical parameters such as SAR (average = 0.17 meq/l), RSC (average = 0.028 meq/l), %Na (average = 7.53), PI (average = 31.28), KI (average = 0.028136 meq/l), SSP (average = 8.3713 %) also conforms to their respective guidelines. However, all the water display relatively high Magnesium ratio (61.43 %), which is at odd to the permissible standard of 50%, hence can cause stunted plant growth. Based on the Water Quality Index (33.12 to 44.40), all water from the boreholes are safe for drinking, in contrast with the hand-dug wells (293.85 and 297.40) believed to be contaminated by anthropogenic activities. Going by our findings, weathering and rock dominance are the major chemical processes through which ion exchange occur in the groundwater which are mostly associated with precipitation and dissolution of rock forming minerals. Also, the ion exchange processes in aquifer was determine through chloro-alkaline indices. Hence, the two hand-dug wells yielded negative CAI (HDW1, CA-I = -0.04987, CA-II = -0.0137; HDW2, CA-I = -0.04153, CA-II = -0.01339), which is interpreted as exchange of Mg2+ and Ca2+ ions present in the water with Na+ and K+ inherent in the rocks. However, all the boreholes recorded positive CAI values (CA-I = 0.672969 to 0.81351, CA-II = 0.107484 to 0.169783), signifying replacement of the Na+ and K+ contained in water by Mg2+ and Ca2+ from the country rocks via base exchange reaction. Notably, Ca-Mg-HCO3 facies is the dominant water type in the area and is associated with normal alkaline group, thus represent a recently recharged water sourced during atmospheric precipitation and dissolution of silicate minerals. The temperature of the borehole water (29 to 30) in the area shows its ambient character, hence good for people who prefer cool and warm water.
Key words: Groundwater Quality, Hydrogeochemistry, Fufore Area, North Eastern Nigeria
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