Mining waste rock-tailings

Fig. 23. Methods of tailings dam constmction (a) upstream method, (b) downstream method, and (c) mine waste rock dam constmction (6).

INTERNATIONAL ATOMIC ENERGY AGENCY, Decommissioning of Surface Facilities and Closeout of Mines, Waste Rock and Mill Tailings from Mining and Milling of Uranium and Thorium Ores, Safety Series No. lll-G-5.2, IAEA, Vienna (under preparation). 

HydrometaHurgical processes for copper can be categorized as (/) acid extraction of copper from oxide ore (2) oxidation and solution of sulfides in waste rock from mining, concentrator tailings, or in situ ore bodies (J) dissolution of copper in concentrates to avoid conventional smelting and (4) extraction of copper from deep-sea manganese nodules. 

Estimation and prediction as to whether waste rock and tailings will produce acid mine drainage (AMD) are precursory to environmental certification, and therefore are a critical step in mine development. Kinetic tests are carried out using a cell or column that are operated over a period of typically 1 year, whereas static tests are a onetime measurement to determine the acid producing potential (AP) and... 

Non-mineralized rocks (mainly basalts and serpentinites), non-valuable mineralizations, and tailings were dumped in five main open-air waste-rock dumps and in several small bodies close to the main mine adits. 

Marescotti, P., Carbone, C., De Capitani, L., Grieco, G., Lucchetti, G., Servida, D. 2008. Mineralogical and geochemical characterisation of open pit tailing and waste rock dumps from the Libiola Fe-Cu sulphide mine (eastern Liguria, Italy). Environmental Geology, 53, 1613-1626. 

Bell, A. B. 1987. Prevention of acid generation in base metal tailings and waste rock. Ir. Proceedings of Acid Mine Drainage. Seminar and Workshop. March 23-26. Halifax. Nova Scotia, pp. 391-410. 

Other heavy metals are also toxic, but fortunately are less widespread and are present in smaller amounts. Mine tailings (waste rock remaining after the valuable minerals have been removed) and waste material from processing plants are major sources of such metals. Many major rivers and lakes have sources of metal contamination from industries whose processes were developed and facilities were built before control of waste was recognized as a major problem. 

The wastes of the metals industry vary with the sector of the industry. Mining creates more wastes (primarily solids) than any of the other sectors. Tailings and waste rock are the two largest volumes of waste that metal production generates. While no attempt has been made to reduce this necessary waste, strict planning, federal and state regulations, and impoundment criteria have been adopted to lessen the impact of these wastes. 

The material properties of the various categories of mineral processing wastes are influenced by the characteristics of the parent rock, the mining and processing methods used, and the methods of handling and/or disposing of the mineral by-product [99-112]. The physical and chemical properties of waste rock, mill tailings, and coarse coal refuse are summarized and discussed in Table 12. 

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