Sand mining

Sand mining is a practice that is becoming an ecological problem as the demand for sand increases in industry and construction. Sand is mined from beaches and inland dunes and dredged from ocean beds and river beds. It is often used in manufacturing as an abrasive, for example, and it is used to make concrete. As communities grow, construction requires less wood and more concrete, leading to a demand for low-cost sand. Sand is also used to replace eroded coastline.

A related process is the mining of mineral sands, such as mineral deposits, grain, wheat, diamond which contain industrial useful minerals, mainly gold and silver. These minerals typically occur combined with ordinary sand. The sand is dug up, the valuable minerals are separated in water by using their different density, and the remaining ordinary sand is re-deposited.

Sand mining is a direct and obvious cause of erosion, and also impacts the local wildlife. For example, sea turtles depend on sandy beaches for their nesting, and sand mining has led to the near extinction of ghariyals (a species of crocodiles) in India. Disturbance of underwater and coastal sand causes turbidity in the water, which is harmful for such organisms as corals that need sunlight. It also destroys fisheries, causing problems for people who rely on fishing for their livelihoods.

Removal of physical coastal barriers such as dunes leads to flooding of beachside communities, and the destruction of picturesque beaches causes tourism to dissipate. Sand mining is regulated by law in many places, but is still often done illegally.

Sand mining by country

Australia

New South Wales

In the 1930s mining operations began on the Kurnell Peninsula (Captain Cook's landing place in Australia) to supply the expanding Sydney building market. It continued until 1990 with an estimate of over 70 million tonnes of sand having been removed. The sand has been valued for many decades by the building industry, mainly because of its high crushed shell content and lack of organic matter, it has provided a cheap source of sand for most of Sydney since sand mining operations began. The site has now been reduced to a few remnant dunes and deep water-filled pits which are now being filled with demolition waste from Sydney's building sites. Removal of the sand has significantly weakened the peninsula's capacity to resist storms. Ocean waves pounding against the reduced Kurnell dune system have threatened to break through to Botany Bay, especially during the storms of May and June back in 1974 and of August 1998.

Queensland

A large and long running sandmine in Queensland, Australia (on North Stradbroke Island) provides a case study in the (disastrous) environmental consequences on a fragile sandy-soil based ecosystem, justified by the provision of low wage casual labor on an island with few other work options.[

Sand mining contributes to the construction of buildings and development. However, the negative effects of sand mining include the permanent loss of sand in areas, as well as major habitat destruction.

From http://en.wikipedia.org/