Lesson l/Learning Event 1
A quarry may have one or more benches, depending upon how it has been developed. Compare the
single and multiple bench quarries illustrated in Figure 2. Single bench quarries have only one working
floor or operating level. Multiple bench quarries have two or more working floors arranged in step-like
fashion.
There are three basic types of quarries: hillside, subsurface, and terrain. Figure 2 shows hillside and
subsurface quarries.
A hillside quarry is operated in rock which is part of the structural geology of a hill. Problems which
may be encountered are overburden removal, grades, and multiple bench operation. Hillside quarries
have the advantage of natural drainage and gravity flow of material from the quarry face.
A subsurface quarry is opened up below the level of the surrounding terrain. The requirements to
remove material from below grade and dispose of it above grade are basic disadvantages. Also,
subsurface quarries do not drain naturally and must be pumped periodically.
A terrain quarry is a temporary operation where the existing terrain is lowered and/or leveled. An
example is an excavation needed to cut a roadway through a rock formation.
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