When potholing, utility crews use a portable vacuum excavator. Very first, test holes, typically measuring six to 12 inches deep, are made together the line in which they want to dig or get started building. They excavate soil with superior-pace suction straight down until the utility line is partially uncovered. https://ewr1.vultrobjects.com/blissdrive/Bess-Utility-Solutions-Hayward/Potholing-Utilities.html