Dust Deposition Impacts at a Liquidated Gold Mine Village: Gauteng Province in South Africa

Abstract

<jats:p>The windy season brings numerous community complaints for gold mining companies situated in the Witwatersrand due to windblown dust from partially rehabilitated tailings storage facilities (TSFs). For communities encroaching onto TSFs, windblown dust is perceived as a health hazard and an environmental challenge. In a study conducted in 2017 by the Lawyers for Human Rights, the community of a gold mine village perceived tailings storage facility 6 (TSF6) and other surrounding tailings storage facilities which are partially rehabilitated to be a health and socio-economic threat. Since 2013, when a nearby gold mining company was liquidated, this community has been complaining about dust fallout. To validate the claims made by the community this paper reports on the dust deposition impacts, and respiratory illnesses risk posed by wind-blown generated dust. The study conducts an air quality assessment using dispersion modelling of windblown dust. Surface material from the TSFs was sampled, analysed for silica and heavy metal content using X-ray fluorescence (XRF) and inductively coupled plasma-mass spectrometry (ICP-MS) respectively. This study finds that PM10 dust fallout, high in silica and uranium content, could potentially pose health threats to the surrounding community. The study further shows that dust deposition is the highest in July–October, with TSF6 posing a nuisance while TSF1 represents a potential health threat owing to its particle size distribution for the surrounding gold mine village community. Potential receptors of the air pollution by dust in this study area include neighbouring property owners, business owners of the nearby shopping centre, the school and the clinic. This study further finds that sudden mine closure due to mine liquidation results in unrehabilitated tailings storage facilities which exacerbates dust deposition.</jats:p>

Advantages and shortcomings of the utilization of recycled wastes as aggregates in structural concretes

“…One of the mining wastes that is starting to attract research efforts for potential use as natural aggregate substitution is gold mining waste rock (GR). Although the statistics for the yearly worldwide generation of this wastes are not available, [9], citing a 2001 publication from the South African Department of Water Affairs and Forestry [10], mentions that the amount of gold mining waste generated in the respective country was of 221 million tons (or 47% of the country's total mineral waste). As this waste is sourced from a rock, in a similar fashion to natural crushed aggregates, its physical properties tend to resemble those of the said natural aggregates.…”

A critical review of the impact of South Africa’s mine closure policy and the winding-up process of mining companies

“…In the BGMC case, a tailings storage facility was left unrehabilitated, and soon after the sudden mine closure, the wind blew the dust towards the nearby communities. The dust became a serious nuisance 4 21 The Mintails Group of companies nonetheless continued to mine the Princess Pits, the Lancaster Pit, the Monarch and Emerald cluster of pits and the Platinum Group of Metals cluster of pits.…”

“…During the liquidation period, tailings storage facility 6 was perceived by the community to be a source of dust fallout (Figure 2). 4 In 2016, when residents of Blyvooruitzicht were interviewed by LHR, they mentioned that the air was not clean. 52 The district just west of the city had recorded 42.24 metric tonnes of tailing-pile dust blowing into the air daily, contaminating livestock and food crops.…”

“…The winding-up and business rescue processes have led to sudden and forced mine closure, resulting in poor rehabilitation of tailings storage facilities (TSFs), which affects nearby communities. 4 Moreno et al 5 defined 'tailings' as the crushed, sand-like by-product or refuse material that is generated during the extraction, crushing, grinding and milling procedures of mined ore. Tailings are rock and other waste materials removed as impurities when waste mineral material is separated from the metal in an ore. The tailings from gold mining contain long-living cyanide metal complexes, naturally occurring radioactive materials and technologically enhanced naturally occurring radioactive materials.…”

Evidence of element volatility at ambient conditions

“…These methods are used to collect PM with different dimensions (> 16 µm ÷ 0.5-0.25 µm). The determination of the mass, chemical, and mineral compositions of PM provides information on the concentrations of the elements in the air and the forms of their occurrence [13][14][15][16][17][18], which allows the assessment of the toxicity and bioavailability of aerosols [12,[19][20]. The migration of metals in the air as part of both ne and ultra ne aerosol particles is considered the main mechanism of air pollution in regions affected by abandoned mine tailings [21,22].…”