Sand mining is a practice that is becoming an ecological problem as the
demand for _sand_ (http://en.wikipedia.org/wiki/Sand) increases in _industry_
(http://en.wikipedia.org/wiki/Industry) and _construction_
(http://en.wikipedia.org/wiki/Construction) . Sand is _mined_
(http://en.wikipedia.org/wiki/Mining) from _beaches_ (http://en.wikipedia.org/wiki/Beach) and inland _dunes_
(http://en.wikipedia.org/wiki/Dune) and _dredged_
(http://en.wikipedia.org/wiki/Dredging) from ocean beds and _river_ (http://en.wikipedia.org/wiki/River)
beds. It is often used in manufacturing as an _abrasive_
(http://en.wikipedia.org/wiki/Abrasive) , for example, and it is used to make _concrete_
(http://en.wikipedia.org/wiki/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 rutile, ilmenite
and zircon, which contain industrial useful minerals, mainly titanium and
zirconium. 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_
(http://en.wikipedia.org/wiki/Erosion) , and also impacts the local _wildlife_
(http://en.wikipedia.org/wiki/Wildlife) . For example, _sea turtles_
(http://en.wikipedia.org/wiki/Sea_turtle) depend on sandy beaches for their nesting, and sand mining has
led to the near extinction of _ghariyals_
(http://en.wikipedia.org/wiki/Ghariyal) (a species of _crocodiles_ (http://en.wikipedia.org/wiki/Crocodiles) )
in _India_ (http://en.wikipedia.org/wiki/India) . Disturbance of underwater
and coastal sand causes _turbidity_ (http://en.wikipedia.org/wiki/Turbidity) in
the water, which is harmful for such organisms as _corals_
(http://en.wikipedia.org/wiki/Coral) that need sunlight. It also destroys _fisheries_
(http://en.wikipedia.org/wiki/Fishery) , causing problems for people who rely on
fishing for their livelihoods.
Removal of physical coastal barriers such as dunes leads to flooding of
beach-side communities, and the destruction of picturesque beaches causes
_tourism_ (http://en.wikipedia.org/wiki/Tourism) to dissipate. Sand mining is
regulated by law in many places, but is still often done illegally.
New South Wales
In the 1930's mining operations began on the _Kurnell Peninsula_
(http://en.wikipedia.org/wiki/Kurnell,_New_South_Wales) (_Captain Cooks_
(http://en.wikipedia.org/wiki/Captain_Cook) landing place in _Australia_
(http://en.wikipedia.org/wiki/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_
(http://en.wikipedia.org/wiki/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_
(http://en.wikipedia.org/wiki/Queensland) , _Australia_ (http://en.wikipedia.org/wiki/Australia) (on
_North Stradbroke Island)_
(http://en.wikipedia.org/wiki/North_Stradbroke_Island#Mining) 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.
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