Mining and industrial activities

Mining and industrial activities produce large quantities of volatiles and dust particles and increase concentrations of trace elements and heavy metals in soils, waters, and vegetation. When mineral deposits containing concentrated trace elements and heavy metals are exposed at the earth s... 

While increased river basin management has led to very low suspended loads for most northern European rivers, mining and industrial activities have resulted in greatly elevated dissolved concentrations. 

Mining and smelting activities Other industrial emissions and effluents Traffic Fly ash... 

Currentiy, trace metal pollution is not a problem in the Amazon River, with the exception perhaps of localized small-scale occurrences. However, the basin includes several sites of elevated metal releases linked to gold and manganese ore mining and industrial discharges from the large cities. Seyler and Boaventura discuss the likelihood of contamination from these sources. Moreover, they come to the provocative conclusion that elevated fluxes of manganese, copper, vanadium, arsenic, and nickel may already be detectable at the river s mouth due to anthropogenic activities in the basin. Possible metal contamination should be taken seriously in the Amazon, as even small amounts of the more toxic metals may lead to widespread adverse effects in the river s aquatic systems. 

Not unnaturally the scene in explosives after the war was one of contraction of manufiicturing capacity. The Waltham Abbey plant practically closed down and, of other government plants, only the huge Gretna plant was operational. Attention turned to experimental and investigational work in the government area and to civilian uses of explosives in mining and associated activities for the private industry plants. 

Heavy metal ions are perhaps the most common of all water pollutants. The heavy metals include such frequendy encountered elements as lead and mercury, as well as many less common ones like cadmium, chromium, nickel, and copper. These metals can, at times, be acutely toxic, causing immediate symptoms, but often they are chronically toxic in very small quantities. Chronic toxicity is characterized by nagging symptoms that lessen normal body functions. Inadequate disposal of wastes from mining or industrial activities causes these metals to find their way into water supplies. In addition, some farming activities and the disposal of household wastes can contribute to the presence of heavy metals in our water supplies. 

Figure 6.7 shows Hg geochemical cycle at pre-industrial and industrial activity stages. It is clear that Hg emission to atmosphere and riverine Hg flux has increased due to human activity such as mining of Hg. It is considered that 2/3 of Hg fluxes to ocean and terrestrial environment is of anthropogenic source (Mason et al. 1994). It is important to know chemical state of Hg and reactions involving Hg in order to elucidate Hg cycle (Bunce 1991). 

Contamination of waters with ai senic occurs as a result of a number of industrial activities such as treatment of industrial wastes, fertilizers, pesticides production, mining, metal smelting etc. and natural processes (e.g. weathering of minerals, volcanic and biological activities). 

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