Modern Mining July 2023

(Photo: Mark Olalde)

recent were slope failures of two TSFs, which were owned by the Mintails Group of Companies), which have impacted ground and surface water resources, air quality, sensitive and protected eco-systems, and the health and safety of local communities and the environment. Legislating TFS Liefferink says the requirement to rehabilitate any environmental damage that occurred during mining, and to make financial provision for the rehabilitation and management of environmental impact or dam age only became a legislative requirement in 1956 with the promulgation of the Mines and Works Act (27 of 1956). To a large extent tailings dams were unregulated throughout the first half of the 20th century. Speaking of the road to TSF legislation, Liefferink explains that in 1978, the Chamber of Mines’ Guideline for Environmental Protection – The Design, Operation and Closure of Metalliferous and Coal Residue Deposits , provided the first structured guideline for the design and operation of tail ings dams in Southern Africa. It was subsequently updated in 1983 and again in 1996. “In 1998, the South African Bureau of Standards’ Code of Practice: Mine Residue, although not legally binding, provided guidelines for the siting, design, construction, operation, management, surveillance and closure of tailings dams in Southern Africa. In South Africa, SANS 10286 (SABS, 1998) has been adopted by many mining companies. Since the adoption of SANS has been so pervasive, it is likely (Photo: Mark Olalde)

— Witwatersrand, South Africa , which states that there are 270 TSFs within the Witwatersrand gold fields alone, containing over 6 billion tons of iron pyrite tailings. The situation is further exacerbated by the fact that South Africa has been left with a legacy of aban doned tailings storage facilities, the majority of which have unstable slopes; no dust or erosion control or stormwater management systems; no functioning piezometers and no penstocks or toe paddocks, access control, warning signs or fences. This has resulted in several TSF failures (the most

TSFs are located close to residential areas.

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July 2023  MODERN MINING  29