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Environmental Effects of Silica Sand Mining

Building activities have grown rapidly in developing countries, and subsequently the demand for construction-grade sand has increased tremendously. Often, these sites are reclaimed through filling in the mines and re-establishing wetlands along rivers, where mining activities had occurred. The long-term effects of silica sand mining include the leaching of toxic substances into soil and water and the poisoning of wildlife.

  1. Damage to River Basins

    • An article in the January 2011 issue of Environmental Management reported on the effects of sand mining in flood plains and the resulting damage to river basins. The study stated that three river basins in southwest India, namely the Chalakudy, Periyar and Muvattupuzha, are being stripped of extremely large quantities of sand. The authors found that mining activities have affected the ecosystems of these rivers by the degradation of their banks. The study concluded with suggestions to improve the rivers and their ecosystems.

    Release of Mercury into the Environment

    • Mercury, a known carcinogen, is a byproduct of the mining industry and difficult to properly quantify in its liquid form, which it assumes at ambient temperatures. A report published in the January 2011 issue of Environmental Management investigated an alternative method for the measurement of mercury from mining operations in California. The researchers found that slow cooling of mercury will transform it to a crystalline form and make the measurement of the element feasible. The authors concluded that this process will eliminate the significant differences in the detection of mercury escaping into the environment from mines along the California coast.

    Influence on Frogs

    • The metamorphosis of frogs, changing from a tadpole to an adult, can be used as an indicator of water pollution. A study appearing in the February 2011 issue of Environmental Pollution investigated the effects of reclaimed wetlands from mining on the metamorphosis of the wood frog, Lithobates sylvaticus. The authors found that metamorphosis was delayed or did not occur at all in tadpoles recovered from reclaimed sites as compared to laboratory-controlled animals. The study showed that thyroid hormones were disrupted by elements in the water from such areas, but claimed that these environments were slowly becoming less toxic with time and should allow the return of wildlife.

    Deposits of Other Metals

    • Sand and silica mines in Virginia have been refilled with biosolids, as a land treatment method, to alleviate the destruction caused by mining. A report in the July 2010 issue of the Journal of Environmental Quality investigated the effects of filling these mines with lime-stabilized biosolids from other parts of the state. The authors found that after a 15-month period, the amounts of copper, nickel and zinc had all significantly increased but that the amounts of these metals pose little risk in contaminating groundwater.

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