Job Description:

• 1) Operates drill supported by upright column, to drill through rock in construction work, such as tunnels, highways, or dams: Fits bit in chuck of drifter.

• 2) Regulates valve to release compressed air that activates drill.

• 3) Turns screw to feed drill into rock.

• 4) Regulates flow of water to remove dust and debris from hole, or blows dust out of hole with compressed air.