The permits have all been issued and it's time to put the pit crews to work.

First the site must be cleared of trees and brush. Overburden is removed. This is the layer of dirt and decaying vegetation that must be cleaned off to get to the actual gravel deposits.

Once the site is cleared the crusher is hauled in along with the excavator and loaders. A crusher is made up of a jaw crusher and feeder, screening unit containing different size screens, cone crusher, and numerous conveyor sections.

Typically, a crusher is operated and maintained by a four-man crew, a crusher foreman, two loader-operators, and a crusher helper. A top crew can disassemble, move and reassemble the entire operation in three to four days.

Raw material, or pit run, is hauled from the excavation site and dumped into the feeder where the jaw crusher separates out the 1/2" size natural materials. The remainder is conveyed to the cone crusher that crushes the material; then it travels to the screening unit and is separated into 1/4" and 3/4" crushed rock. The material travels between these two units until it is all crushed to size. Conveyors carry it to the stockpile "hills" you see in the picture above. From the stockpile, it is loaded into dump trucks and hauled away to be used as roadbase or hot mix aggregate.

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