Tailings Storage Facilities (TSFs), essential to mining operations, pose significant environmental risks, particularly through the leaching of toxic chemicals into the surface and groundwater. Therefore, effective environmental monitoring around TSFs is critical for sustainable mining practices. This study characterized borehole water quality around the TSF at Geita Gold Mine (GGM), one of Africa’s largest gold operations, to assess potential for seepage and its spatiotemporal variations. Key water quality parameters including pH, sulfate, nitrate, and total dissolved solids (TDS) were quantified using eight shallow and deep boreholes located both upstream and downstream of the TSF, with differences analyzed statistically using the Wilcoxon signed-rank and Pearson correlation tests across seasons and locations. Downstream boreholes consistently recorded significantly higher concentrations for every parameter compared to upstream locations. Upstream parameter levels remained low, ranging from pH (5.5–7.4), sulfate (1–8 mg/L), nitrate (0.02–14.10 mg/L), and TDS (40–221 mg/L). In sharp contrast, downstream boreholes showed considerably wider ranges and elevated concentrations: pH (4.5–8.0), sulfate (3–2398 mg/L), nitrate (0.02–55.10 mg/L), and TDS (55–3847 mg/L). Importantly, this led to several regulatory breaches: three downstream boreholes exceeded the national discharge limit for nitrate; five boreholes surpassed the 500 mg/L level for sulfate; and two boreholes recorded TDS levels above the WHO guideline of 1500 mg/L. These differences suggest the presence of seepage downstream of the TSF. Further analysis indicated that borehole depth had no direct effect on these variables. Additionally, species levels were generally lower during the dry season than the wet season. The study points out the need for continuous environmental monitoring to safeguard TSFs and support sustainable mining investments.
Mataro et al. (Sat,) studied this question.