Answer to Question 1
Traffic in the vicinity of the excavation (heavy or light? Cars? Trucks? Heavy equipment?)
Proximity of structures or equipment to the excavation; condition of structures; type of equipment (does it cause vibration?)
Soil factors (moist or dry? Packed or loose?)
Surface and ground water; depth at which the excavation will begin to accumulate water
Utilities (overhead and underground)
Weather? (is rain likely?)
Answer to Question 2
Established before beginning construction of the masonry wall.
Must be at least 4 feet wider than the height of the masonry wall and must run its entire length.
Must be located on the side of the masonry wall that will not be scaffolded.
Only employees actively engaged in constructing the masonry wall may be allowed in the area marked off for limited access.
Must remain in place until the masonry wall is adequately supported to prevent collapse.