SULFUR SPECIATION IN REGOLITH AQUIFERS AT ENUGU, SOUTHEASTERN NIGERIA
DOI:
https://doi.org/10.58885/ijees.v1i1.15.eoKeywords:
Sulfur specification, Microbial Sulfur Cycling, Redox Reactions, Groundwater geochemistry, Sulfate-reducing bacteria, Regolith aquifersAbstract
This study investigates the geochemical behavior and microbial interactions influencing sulfur speciation in regolith aquifers across Enugu, Southeastern Nigeria. A total of 30 groundwater samples from multiple locations such as Centenary, 9th mile, Ologo, Trans-Ekulu, New-artizan and Amechi were analyzed using Eh-pH diagrams for the sulfur system (SO₄²⁻/HSO₄⁻/HS⁻/H₂S/S). From the result, the Eh-pH plots revealed diverse redox environments ranging from oxidizing to strongly reducing conditions. It was observed that, Winners Estate HDW and similar sites which were plotted in the oxidizing zone dominated by SO₄²⁻, while Ezenweke Street HDW and similar sites displayed reducing conditions where sulfur exists predominantly as HS⁻ or H₂S. These redox environments suggest varying degrees of microbial activity, particularly sulfate-reducing bacteria, influencing sulfur transformations. The presence of reduced sulfur species in some samples indicates potential risks such as corrosion, odor issues, and the mobilization of toxic trace metals like arsenic and manganese. The study show and buttress on the importance of redox-sensitive monitoring for effective groundwater management and public health protection in urban and peri-urban settings.
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