In order to address residual and latent impacts, we strongly recommend that the City of Johannesburg should adopt the precautionary approach and consider the following risks when determining its developmental framework:
- The near certainty of contaminated water, which will require some form of decontamination treatment, decanting from closed underground mines, or from lower lying interconnected neighbouring mines;
- The near certainty of sulphate, chloride, metal and NORM contamination of soils and sediments by seepage from unlined tailings storage facilities, tailings spillages and plant discharges, and the potential for contamination of downstream /downwind soils and sediments;
- The near certainty of sulphate, chloride, metal and NORM contamination of surface water bodies and their sediments, and groundwater, by seepage from unlined tialings storage facilities, tailings spillages, plant discharges and underground workings. In In addition, the potential contamination of surface soils overlying shallow polluted groundwater via evaporative pathways during dry seasons;
- The potential for slat, sulphate, chloride, metal and NORM contamination of corp soils irrigated with contaminated surface water or contaminated groundwater.
- The concomitant loss of genetic / biodiversity and potentially ecosystem goods and services on disturbed, fragmented or polluted properties.
- The potential for bioaccumulation of some metals and NORMs by flora and fauna;
- The potential for exposure of fauna and humans to bioaccumulated pollutants.
- The potential for acute and latent toxicity impacts of bioaccumulated pollutants on humans and the potential for radioactivity impacts form NORMS on humans;
- The potential for human disease as a result of exposure to windblown dust from Tailings Storage Facilities;
- The potential for structural damage to buildings and other structures, and human injury, by mining exacerbated seismicity.
- In dolomitic regions, the potential for structural damage to buildings and other structures, and human injury, by mining exacerbated sinkhole formation.
The potential for uncontrolled future land uses on or within the zone of influence of tailings storage facilities, footprints and mineral processing facilities, such as human settlement and recreation, food crops and home vegetable gardens, livestock grazing and informal re-mining or scavenging, all of which are incompatible with safety and the fragile status of lands under rehabilitation, and could exacerbate liabilities for the state post closure.