GPRS Utility Locates in a Substation in Covington, Kentucky
Ground Penetrating Radar Systems - GPRS – completed a GPR utility locate in a substation in Covington, Kentucky. A contractor was trenching multiple conduits in and replacing breakers within the substation. The site contact explained he had to have all of the underground infrastructure located prior to digging. They also needed all of the grounding located.
There were multiple utilities coming off poles, grounding, and transformers that needed to be located. To start the process, we walked the site with the contact and white lined the path of excavation. We asked how wide the located needed to be and he stated 10’ on each side of the white line for the conduit to be trenched in.
To start, we used our Ground Penetrating Utility cart and performed radar on the dig site. We scan in a grid pattern to ensure we see all of the utilities. Scanning in a grid pattern ensures we will not miss anything. It will show us utilities traveling at an angle and directly across our dig path. Once completed scanning with the ground penetrating radar utility cart, we coordinated our findings with the on-site contact. We explained our max scan depths which we were able to see utilities at, also what we found and what the markings mean.
After we have scanned the proposed dig path, we used the EM Pipe Locator. We directly connected and clamped to all visible utilities and grounds. First, we directly connected to the transformers. After that, we clamped to all of the utilities coming down the poles. There was one utility we were unable to get a tone on from clamping, therefore we use what’s called a “Jameson Reel.” This is a fiberglass fishtape that allows us to trace utilities that are either untonable or do not have metal sheathing which creates continuity. This allowed us to trace the utility that we would have otherwise been unable to.
Once we completed the utility cart scan and connected to all of the utilities, we then clamped around the grounds and marked the ground grid inside of the substation. The ground grid is critical to the infrastructure inside the facility and needs to be protected. We were able to located and mark all of the grounds within the substation.
Finally, we performed what’s called a passive sweep using the EM Pipe Locator. We walk grid patterns to ensure we detect every possible utility. Using GRPS is standard operating procedure for many companies. This ensures the safety for the contractor and the infrastructure.
After the locate process was complete, we preformed a Google Earth Overlay by using GPS on all the utilities to provide a general layout of all of the utilities. This provided the client with an overview of the utilities for future reference.