The study assessed the quality of the influent, effluent, sludge of the Malamulele Wastewater Treatment Plant (MWTP) and its impact on the water quality of Mandzoro River. In the effluent discharge, the levels of iron, zinc, copper and lead were 0.5 ppm, 0.1 ppm, 0.05 ppm and 0.02 ppm respectively. These heavy metals were also found in the dried sludge. The chemical analysis for phosphates and nitrates showed that they were absent from the upstream section but were present in the downstream section at phosphates (20 ppm) and nitrates (9 ppm). A high concentration of chloride was found in the effluent. The river health assessment, based on the absence or presence of certain macroinvertebrates, showed a presence of pollution resistant aquatic macroinvertebrates, the Psychodidae and Thiaridae which were found in the downstream, but were absent in the upstream.

Abandoned gold mine sites are generally characterised by severe environmental problems and physical hazards. Because of socio-economic problems confronting communities around abandoned mine sites, historic and abandoned gold mines have become hot-spots for artisanal and small-scale miners. These mining activities at times thwart the efforts of rehabilitation at these sites. This article details how artisanal mining operations have frustrated rehabilitation efforts of abandoned mine shafts in the Sutherland goldfield. The field investigation of abandoned shafts and analysis of the nature of artisanal mining operations in the Sutherland goldfield revealed that artisanal mining involving digging around collars of sealed shafts is a major threat to the stability of the shafts and their sealing structures. In addition, artisanal mining operations have increased the safety risks of the abandoned shafts in the area. This has also been worsened by the fact that a large number of people, especially women and children, are exposed to the hazards of the abandoned mine sites. This article emphasises an urgent need for the development of holistic and cohesive strategies for dealing with the problems of abandoned gold mine shafts wherever they exist in the country as opposed to simply closing them up.

Objective: The purpose of this study was to estimate the levels of Suspended Particulate Matter (SPM) in ambient air within Mukula mine and the potential risks to mineworkers and inhabitants of the adjoining Mukula community’s health. Methods : An SPM was used to measure the levels of particulate matter (PM10) in and around the mining site. One-way Analysis of Variance (ANOVA) was used to determine significance level of PM10 in ambient air. Results: Suspended particulate matter in the air ranged from 60.25 to 1820.45 µg/m3. The lowest value of SPM was more than four times the required World Health Organisation’s allowable level in ambient air, which the mine workers and locals would be inhaling. Conclusion: Continuous inhalation of mine dusts by mine workers and locals could result in pulmonary fibrosis, silicosis and lung cancer. The findings from this study support the need to have in place the necessary control measures that will drastically reduce SPM in the air. Such measure includes wet drilling and blasting, sprinkling of water on the mine roads and planting of vegetation around the mines and neighbouring communities.

The purpose of the study was to assess the level of toxic metals (Cd, Co, Cu, Cr, Mn, Pb, Ni and Zn) in an abandoned Nyala mine tailings dams and in Aristida congesta, a native grass. The mean value of toxic metals in the mine tailings soils 1 were: Mn (498.78 ± 2.42 mg/kg); Ni (114.62 ± 2.64 mg/kg); Cr (81.30 ± 3.03 mg/kg); Co (77.10 ± 0.46 mg/kg); Zn (58.31 ± 0.90 mg/kg); Cu (26.32 ± 0.12 mg/kg); Pb (14.13 ± 0.70 mg/kg) and Cd (10.00 ± 0.00 mg/kg) respectfully. The mean value of toxic metals in the mine tailings soils 2 were: Ni (959.31 ± 9.72 mg/kg); Mn (424.24 ± 0.76 mg/kg); Co (63.44 ± 0.83 mg/kg); Cr (56.52 ± 0.69 mg/kg); Zn (46.26 ± 0.92 mg/kg); Cu (22.03 ± 0.64 mg/kg); Pb (17.57 ± 0.87 mg/kg) and Cd (1.13 ± 0.12 mg/kg). The pH of mine tailings soils 1 was 7.97 ± 0.06 and electrical conductivity was 4.92 ± 0.06 mS/cm. The pH of mine tailings soils 2 was 8.94 ± 0.06 and electrical conductivity was 1.88 ± 0.10 mS/cm. A. congesta, was growing in abundance in mine tailings soils 2 and none in mine tailings soils 1. The reason may be due to cumulative toxic metals and Ni which was eight times more in mine tailings soils 1. A. congesta accumulated the toxic metals (sum of roots, stem and leaves) as follows: Cr (184.55 mg/kg); Mn (104.60 mg/kg); Ni (95.99 mg/kg); Co (18.66 mg/kg); Zn (10.13 mg/kg); Cu (8.93 mg/kg); Pb (4.40 mg/kg) and Cd (0.93 mg/kg). The bioaccumulation coefficient was 2.27 which mean that A. congesta is a hyperaccumulator for Cr. Water Pollution XI 415Thus A. congesta is recommended to rehabilitate the mine tailings and provide a cover against wind and water erosion.

Mining waste are materials that result from the exploration, mining and processing of substances and can consist of natural materials, processed to varying degrees during the ore-processing and enrichment phases, and possibly containing chemical, inorganic and organic additives. Evaluation of the REEs potential of the Klein Letaba tailings dam was envisaged to assist in the containment at the currently un-rehabilitated mine tailings material. These tailings are a concern to the livelihood of nearby communities in the Giyani area due to their threat to water and soil quality. The methodologies used in this study consist of sampling, sample preparation and analysis using X-ray spectrometry technique and calculation of the tonnage of the tailings material using the Trapezoidal rule method. The results indicated that the REE abundance at the tailings dump in their decreasing concentration were Yb > La > Ce > Gd > Sm > Dy > Y > Er > Tb > Eu > Sc. The tailings dam was found to have significant levels of both LREEs and HREEs, which are above the upper continental crust thresholds. For instance, the HREEs Gd, Dy, and Yb were almost 10 times or more than the crustal abundances and this being 56, 46 and 17 mg/kg respectively. The LREEs and HREEs had also a total concentration 602 and 769 mg/kg respectively. The calculated volume of the tailings material was found to be 527,081 m3 and the tonnage was derived to be 1,291 349.0 tons of tailings material at the site. Consequently, the total LREEs and HREEs contained in the material was estimated to be 843 tons and worth re-evaluating. The paper uses REEs at this study site to illustrate how other un-rehabilitated sites can be re-evaluated and attract investment towards exploiting them and subsequently assisting in tailings containment. However, the REEs at Klein Letaba tailings dam was found to be uneconomic to exploit under the current prices and technology.