Strip mining is most often used on the plains. Large
equipment, such as draglines, removes the overlying soil and
rock (overburden) to expose a relatively horizontal coal seam.
Overburden is placed in piles behind the area being mined. When
extraction is complete, the overburden is replaced and the land
is returned as much as possible to its former state.
Strip mining is used on the prairies where coal seams are
fairly horizontal and close to the surface. Large machinery
exposes and extracts the coal in a series of rows called strips.
In the early days of strip mining there arose a prejudice in
some circles over the use of strip-produced coal. It was felt
that strip-mined coal was not as good as underground coal. There
was no basis to this, however, as the only difference between
these coals is the method of getting at it. Stripping techniques
are actually less costly, and may produce a lower-cost fuel to
homes and industries throughout Alberta and Canada.
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