This module requires trainees to perform stand-by activities while an excavator performs excavation work near a critical (e.g., high pressure, large diameter, etc.) natural gas facility. The trainee must determine if power operated excavation is permitted for use or if hand digging is required due to being within the tolerance zone of the locate markings and underground facilities. In addition, the trainee must be able to identify any Abnormal Operating Conditions (AOC’s) that may be encountered during the excavation work. These AOC’s may include improper backfill material, damaged or corroded piping, or gas piping that may be too shallow.