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Land Stewardship
Extracting any raw material
takes a toll on the environment. But extracting
the raw materials for cement has a relatively
low environmental impact, and cement companies
are taking measures to minimize the disruption
even further.
Limestone usually comes from a quarry at or near
the plant while other materials such as clay,
shale, iron ore, and sand are usually obtained
from other nearby sources. Because these raw materials
are among the most common on Earth, cement producers
can mitigate environmental impact through careful
site selection and operating procedures. At the
end of their useful life, cement quarries can
be reclaimed as parks, recreational areas, or
other developments.
Byproducts generated during cement
making are either recycled into the process or
for other beneficial uses. A case in point is
cement kiln dust (CKD). CKD is the material removed
from the kiln exhaust gases by pollution-control
devices. The industry has greatly reduced the
amount of CKD disposed through process improvements.
Recycling CKD offsets the use of limestone and
other raw virgin materials, conserves energy,
and makes good business sense. CKD that can't
be recycled back into the process is either responsibly
managed in a monofill on site or sold for a variety
of beneficial uses. For those cement plants who
use CKD monofills, proper management and closure
of them is an integral part of their operations.
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Reclamation of
Former Quarries and CKD Monofills

In 2003, a cement plant in Mason City, Iowa, completed various
projects to close former cement kiln dust (CKD) landfills and quarry operations.
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