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Acid Mine Drainage Formation, Dissemination and Control: Mining and Hydrological Perspectives
Published in Geoffrey S. Simate, Sehliselo Ndlovu, Acid Mine Drainage, 2021
Mine dewatering entails the pumping of water from mine working areas such as mine pits to facilitate mining operations (Szczepiński, 2019). Such water may originate from two sources: (1) surface water runoff from surrounding areas, and/or (2) groundwater in cases where mining occurs below the groundwater table. Mine dewatering systems include wells, well galleries, boreholes and pumping units. Subsequently, groundwater pumping lowers the groundwater table and alters groundwater flow directions. Excessive dewatering or groundwater pumping may significantly alter the groundwater balance, leading to aquifer drying or groundwater recession. Excessive groundwater pumping also creates a large void space in the sub-surface. Therefore, as the geological material settles to fill up the void space, this causes ground subsidence (Morrison et al., 2019).
The Range of Environmental and Social Concerns
Published in Karlheinz Spitz, John Trudinger, Mining and the Environment, 2019
Karlheinz Spitz, John Trudinger
Environmental and social impacts associated with surface and underground mining are similar in nature, but often different in magnitude. Compared to surface mining, underground mining requires relatively small openings and limited excavation. Underground mines also produce relatively little waste rock. Tailings are often used as backfill materials eliminating the need for large on-land tailings storage areas. Accordingly, two of the main sources of environmental impacts from mining (changes in landform and mine wastes) are greatly reduced. Since underground mines are generally much smaller in terms of production than surface mines, the fleet of mining equipment, and ancillary mining operations are also of smaller scale. Loosely speaking, this also leads to smaller environmental impacts. On the other hand, underground mining is invariably more labour intensive, so that there may be more employment opportunities than for a surface mine of similar production, but this may not benefit local communities as underground mining requires more highly skilled workers. Underground mines may also require more extensive mine dewatering, with the potential for more severe impacts related to water management.
Coal Flotation in Saline Water: Effects of Electrolytes on Interfaces and Industrial Practice
Published in Mineral Processing and Extractive Metallurgy Review, 2021
Ghislain Bournival, Feng Zhang, Seher Ata
Data available for NSW starting from 2009 (Australian Bureau of Statistics 2019) are plotted in Figure 1 and show that the consumption of water is higher from 2012. The volume of water sourced from streams (i.e. fresh water from a river) and distributed water (i.e. bought) was significantly higher in 2009. The water reuse is mostly rainwater and drainage water. The increase in water consumption has been met by the use of self-extracted water, which includes water from the environment (e.g. groundwater, lakes). In many cases, water is obtained from mine dewatering. Contaminants of mine water and process water are discussed in the following section.